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| author |   Jakub Kicinski <kuba@kernel.org> | 2021-07-31 11:23:25 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-07-31 11:23:26 -0700 |
| commit | d39e8b92c34113e0e406c9853d655b1350a15624 (patch) | |
| tree | 024fa3db1cea7d90dbc9cdb353fab96d55801f07 /tools | |
| parent | Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net (diff) | |
| parent | Merge branch 'tools: bpftool: update, synchronise and validate types and options' (diff) | |
| download | linux-dev-d39e8b92c34113e0e406c9853d655b1350a15624.tar.xz linux-dev-d39e8b92c34113e0e406c9853d655b1350a15624.zip | |
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Andrii Nakryiko says:
====================
bpf-next 2021-07-30
We've added 64 non-merge commits during the last 15 day(s) which contain
a total of 83 files changed, 5027 insertions(+), 1808 deletions(-).
The main changes are:
1) BTF-guided binary data dumping libbpf API, from Alan.
2) Internal factoring out of libbpf CO-RE relocation logic, from Alexei.
3) Ambient BPF run context and cgroup storage cleanup, from Andrii.
4) Few small API additions for libbpf 1.0 effort, from Evgeniy and Hengqi.
5) bpf_program__attach_kprobe_opts() fixes in libbpf, from Jiri.
6) bpf_{get,set}sockopt() support in BPF iterators, from Martin.
7) BPF map pinning improvements in libbpf, from Martynas.
8) Improved module BTF support in libbpf and bpftool, from Quentin.
9) Bpftool cleanups and documentation improvements, from Quentin.
10) Libbpf improvements for supporting CO-RE on old kernels, from Shuyi.
11) Increased maximum cgroup storage size, from Stanislav.
12) Small fixes and improvements to BPF tests and samples, from various folks.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (64 commits)
tools: bpftool: Complete metrics list in "bpftool prog profile" doc
tools: bpftool: Document and add bash completion for -L, -B options
selftests/bpf: Update bpftool's consistency script for checking options
tools: bpftool: Update and synchronise option list in doc and help msg
tools: bpftool: Complete and synchronise attach or map types
selftests/bpf: Check consistency between bpftool source, doc, completion
tools: bpftool: Slightly ease bash completion updates
unix_bpf: Fix a potential deadlock in unix_dgram_bpf_recvmsg()
libbpf: Add btf__load_vmlinux_btf/btf__load_module_btf
tools: bpftool: Support dumping split BTF by id
libbpf: Add split BTF support for btf__load_from_kernel_by_id()
tools: Replace btf__get_from_id() with btf__load_from_kernel_by_id()
tools: Free BTF objects at various locations
libbpf: Rename btf__get_from_id() as btf__load_from_kernel_by_id()
libbpf: Rename btf__load() as btf__load_into_kernel()
libbpf: Return non-null error on failures in libbpf_find_prog_btf_id()
bpf: Emit better log message if bpf_iter ctx arg btf_id == 0
tools/resolve_btfids: Emit warnings and patch zero id for missing symbols
bpf: Increase supported cgroup storage value size
libbpf: Fix race when pinning maps in parallel
...
====================
Link: https://lore.kernel.org/r/20210730225606.1897330-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'tools')
63 files changed, 4514 insertions, 1599 deletions
diff --git a/tools/bpf/bpftool/Documentation/bpftool-btf.rst b/tools/bpf/bpftool/Documentation/bpftool-btf.rst index ff4d327a582e..88b28aa7431f 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-btf.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-btf.rst @@ -12,7 +12,8 @@ SYNOPSIS **bpftool** [*OPTIONS*] **btf** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | {**-d** | **--debug** } | + { **-B** | **--base-btf** } } *COMMANDS* := { **dump** | **help** } @@ -73,6 +74,20 @@ OPTIONS ======= .. include:: common_options.rst + -B, --base-btf *FILE* + Pass a base BTF object. Base BTF objects are typically used + with BTF objects for kernel modules. To avoid duplicating + all kernel symbols required by modules, BTF objects for + modules are "split", they are built incrementally on top of + the kernel (vmlinux) BTF object. So the base BTF reference + should usually point to the kernel BTF. + + When the main BTF object to process (for example, the + module BTF to dump) is passed as a *FILE*, bpftool attempts + to autodetect the path for the base object, and passing + this option is optional. When the main BTF object is passed + through other handles, this option becomes necessary. + EXAMPLES ======== **# bpftool btf dump id 1226** @@ -217,3 +232,34 @@ All the standard ways to specify map or program are supported: **# bpftool btf dump prog tag b88e0a09b1d9759d** **# bpftool btf dump prog pinned /sys/fs/bpf/prog_name** + +| +| **# bpftool btf dump file /sys/kernel/btf/i2c_smbus** +| (or) +| **# I2C_SMBUS_ID=$(bpftool btf show -p | jq '.[] | select(.name=="i2c_smbus").id')** +| **# bpftool btf dump id ${I2C_SMBUS_ID} -B /sys/kernel/btf/vmlinux** + +:: + + [104848] STRUCT 'i2c_smbus_alert' size=40 vlen=2 + 'alert' type_id=393 bits_offset=0 + 'ara' type_id=56050 bits_offset=256 + [104849] STRUCT 'alert_data' size=12 vlen=3 + 'addr' type_id=16 bits_offset=0 + 'type' type_id=56053 bits_offset=32 + 'data' type_id=7 bits_offset=64 + [104850] PTR '(anon)' type_id=104848 + [104851] PTR '(anon)' type_id=104849 + [104852] FUNC 'i2c_register_spd' type_id=84745 linkage=static + [104853] FUNC 'smbalert_driver_init' type_id=1213 linkage=static + [104854] FUNC_PROTO '(anon)' ret_type_id=18 vlen=1 + 'ara' type_id=56050 + [104855] FUNC 'i2c_handle_smbus_alert' type_id=104854 linkage=static + [104856] FUNC 'smbalert_remove' type_id=104854 linkage=static + [104857] FUNC_PROTO '(anon)' ret_type_id=18 vlen=2 + 'ara' type_id=56050 + 'id' type_id=56056 + [104858] FUNC 'smbalert_probe' type_id=104857 linkage=static + [104859] FUNC 'smbalert_work' type_id=9695 linkage=static + [104860] FUNC 'smbus_alert' type_id=71367 linkage=static + [104861] FUNC 'smbus_do_alert' type_id=84827 linkage=static diff --git a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst index baee8591ac76..3e4395eede4f 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst @@ -12,7 +12,8 @@ SYNOPSIS **bpftool** [*OPTIONS*] **cgroup** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } | + { **-f** | **--bpffs** } } *COMMANDS* := { **show** | **list** | **tree** | **attach** | **detach** | **help** } diff --git a/tools/bpf/bpftool/Documentation/bpftool-feature.rst b/tools/bpf/bpftool/Documentation/bpftool-feature.rst index dd3771bdbc57..ab9f57ee4c3a 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-feature.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-feature.rst @@ -12,7 +12,7 @@ SYNOPSIS **bpftool** [*OPTIONS*] **feature** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } } *COMMANDS* := { **probe** | **help** } diff --git a/tools/bpf/bpftool/Documentation/bpftool-gen.rst b/tools/bpf/bpftool/Documentation/bpftool-gen.rst index 7cd6681137f3..2ef2f2df0279 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-gen.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-gen.rst @@ -12,7 +12,8 @@ SYNOPSIS **bpftool** [*OPTIONS*] **gen** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } | + { **-L** | **--use-loader** } } *COMMAND* := { **object** | **skeleton** | **help** } @@ -152,6 +153,12 @@ OPTIONS ======= .. include:: common_options.rst + -L, --use-loader + For skeletons, generate a "light" skeleton (also known as "loader" + skeleton). A light skeleton contains a loader eBPF program. It does + not use the majority of the libbpf infrastructure, and does not need + libelf. + EXAMPLES ======== **$ cat example1.bpf.c** diff --git a/tools/bpf/bpftool/Documentation/bpftool-iter.rst b/tools/bpf/bpftool/Documentation/bpftool-iter.rst index 51f49bead619..471f363a725a 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-iter.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-iter.rst @@ -12,6 +12,8 @@ SYNOPSIS **bpftool** [*OPTIONS*] **iter** *COMMAND* + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } } + *COMMANDS* := { **pin** | **help** } ITER COMMANDS diff --git a/tools/bpf/bpftool/Documentation/bpftool-link.rst b/tools/bpf/bpftool/Documentation/bpftool-link.rst index 5f7db2a837cc..0de90f086238 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-link.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-link.rst @@ -12,7 +12,8 @@ SYNOPSIS **bpftool** [*OPTIONS*] **link** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } | + { **-f** | **--bpffs** } | { **-n** | **--nomount** } } *COMMANDS* := { **show** | **list** | **pin** | **help** } diff --git a/tools/bpf/bpftool/Documentation/bpftool-map.rst b/tools/bpf/bpftool/Documentation/bpftool-map.rst index 3d52256ba75f..d0c4abe08aba 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-map.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-map.rst @@ -12,7 +12,8 @@ SYNOPSIS **bpftool** [*OPTIONS*] **map** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } | + { **-f** | **--bpffs** } | { **-n** | **--nomount** } } *COMMANDS* := { **show** | **list** | **create** | **dump** | **update** | **lookup** | **getnext** diff --git a/tools/bpf/bpftool/Documentation/bpftool-net.rst b/tools/bpf/bpftool/Documentation/bpftool-net.rst index d8165d530937..1ae0375e8fea 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-net.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-net.rst @@ -12,7 +12,7 @@ SYNOPSIS **bpftool** [*OPTIONS*] **net** *COMMAND* - *OPTIONS* := { [{ **-j** | **--json** }] [{ **-p** | **--pretty** }] } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } } *COMMANDS* := { **show** | **list** | **attach** | **detach** | **help** } diff --git a/tools/bpf/bpftool/Documentation/bpftool-perf.rst b/tools/bpf/bpftool/Documentation/bpftool-perf.rst index e958ce91de72..ce52798a917d 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-perf.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-perf.rst @@ -12,7 +12,7 @@ SYNOPSIS **bpftool** [*OPTIONS*] **perf** *COMMAND* - *OPTIONS* := { [{ **-j** | **--json** }] [{ **-p** | **--pretty** }] } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } } *COMMANDS* := { **show** | **list** | **help** } diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index fe1b38e7e887..91608cb7e44a 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -12,7 +12,9 @@ SYNOPSIS **bpftool** [*OPTIONS*] **prog** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } | + { **-f** | **--bpffs** } | { **-m** | **--mapcompat** } | { **-n** | **--nomount** } | + { **-L** | **--use-loader** } } *COMMANDS* := { **show** | **list** | **dump xlated** | **dump jited** | **pin** | **load** @@ -48,10 +50,11 @@ PROG COMMANDS | **struct_ops** | **fentry** | **fexit** | **freplace** | **sk_lookup** | } | *ATTACH_TYPE* := { -| **msg_verdict** | **stream_verdict** | **stream_parser** | **flow_dissector** +| **msg_verdict** | **skb_verdict** | **stream_verdict** | **stream_parser** | **flow_dissector** | } | *METRICs* := { -| **cycles** | **instructions** | **l1d_loads** | **llc_misses** +| **cycles** | **instructions** | **l1d_loads** | **llc_misses** | +| **itlb_misses** | **dtlb_misses** | } @@ -223,6 +226,20 @@ OPTIONS Do not automatically attempt to mount any virtual file system (such as tracefs or BPF virtual file system) when necessary. + -L, --use-loader + Load program as a "loader" program. This is useful to debug + the generation of such programs. When this option is in + use, bpftool attempts to load the programs from the object + file into the kernel, but does not pin them (therefore, the + *PATH* must not be provided). + + When combined with the **-d**\ \|\ **--debug** option, + additional debug messages are generated, and the execution + of the loader program will use the **bpf_trace_printk**\ () + helper to log each step of loading BTF, creating the maps, + and loading the programs (see **bpftool prog tracelog** as + a way to dump those messages). + EXAMPLES ======== **# bpftool prog show** @@ -326,3 +343,16 @@ EXAMPLES 40176203 cycles (83.05%) 42518139 instructions # 1.06 insns per cycle (83.39%) 123 llc_misses # 2.89 LLC misses per million insns (83.15%) + +| +| Output below is for the trace logs. +| Run in separate terminals: +| **# bpftool prog tracelog** +| **# bpftool prog load -L -d file.o** + +:: + + bpftool-620059 [004] d... 2634685.517903: bpf_trace_printk: btf_load size 665 r=5 + bpftool-620059 [004] d... 2634685.517912: bpf_trace_printk: map_create sample_map idx 0 type 2 value_size 4 value_btf_id 0 r=6 + bpftool-620059 [004] d... 2634685.517997: bpf_trace_printk: prog_load sample insn_cnt 13 r=7 + bpftool-620059 [004] d... 2634685.517999: bpf_trace_printk: close(5) = 0 diff --git a/tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst b/tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst index 506e70ee78e9..02afc0fc14cb 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-struct_ops.rst @@ -12,7 +12,7 @@ SYNOPSIS **bpftool** [*OPTIONS*] **struct_ops** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] } + *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } } *COMMANDS* := { **show** | **list** | **dump** | **register** | **unregister** | **help** } diff --git a/tools/bpf/bpftool/Documentation/bpftool.rst b/tools/bpf/bpftool/Documentation/bpftool.rst index e7d949334961..bb23f55bb05a 100644 --- a/tools/bpf/bpftool/Documentation/bpftool.rst +++ b/tools/bpf/bpftool/Documentation/bpftool.rst @@ -18,15 +18,15 @@ SYNOPSIS *OBJECT* := { **map** | **program** | **cgroup** | **perf** | **net** | **feature** } - *OPTIONS* := { { **-V** | **--version** } | { **-h** | **--help** } - | { **-j** | **--json** } [{ **-p** | **--pretty** }] } + *OPTIONS* := { { **-V** | **--version** } | + { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-d** | **--debug** } } *MAP-COMMANDS* := - { **show** | **list** | **create** | **dump** | **update** | **lookup** | **getnext** - | **delete** | **pin** | **event_pipe** | **help** } + { **show** | **list** | **create** | **dump** | **update** | **lookup** | **getnext** | + **delete** | **pin** | **event_pipe** | **help** } - *PROG-COMMANDS* := { **show** | **list** | **dump jited** | **dump xlated** | **pin** - | **load** | **attach** | **detach** | **help** } + *PROG-COMMANDS* := { **show** | **list** | **dump jited** | **dump xlated** | **pin** | + **load** | **attach** | **detach** | **help** } *CGROUP-COMMANDS* := { **show** | **list** | **attach** | **detach** | **help** } diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index cc33c5824a2f..88e2bcf16cca 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -260,7 +260,8 @@ _bpftool() # Deal with options if [[ ${words[cword]} == -* ]]; then - local c='--version --json --pretty --bpffs --mapcompat --debug' + local c='--version --json --pretty --bpffs --mapcompat --debug \ + --use-loader --base-btf' COMPREPLY=( $( compgen -W "$c" -- "$cur" ) ) return 0 fi @@ -278,7 +279,7 @@ _bpftool() _sysfs_get_netdevs return 0 ;; - file|pinned) + file|pinned|-B|--base-btf) _filedir return 0 ;; @@ -291,7 +292,8 @@ _bpftool() # Remove all options so completions don't have to deal with them. local i for (( i=1; i < ${#words[@]}; )); do - if [[ ${words[i]::1} == - ]]; then + if [[ ${words[i]::1} == - ]] && + [[ ${words[i]} != "-B" ]] && [[ ${words[i]} != "--base-btf" ]]; then words=( "${words[@]:0:i}" "${words[@]:i+1}" ) [[ $i -le $cword ]] && cword=$(( cword - 1 )) else @@ -343,7 +345,8 @@ _bpftool() local PROG_TYPE='id pinned tag name' local MAP_TYPE='id pinned name' - local METRIC_TYPE='cycles instructions l1d_loads llc_misses' + local METRIC_TYPE='cycles instructions l1d_loads llc_misses \ + itlb_misses dtlb_misses' case $command in show|list) [[ $prev != "$command" ]] && return 0 @@ -404,8 +407,10 @@ _bpftool() return 0 ;; 5) - COMPREPLY=( $( compgen -W 'msg_verdict stream_verdict \ - stream_parser flow_dissector' -- "$cur" ) ) + local BPFTOOL_PROG_ATTACH_TYPES='msg_verdict \ + skb_verdict stream_verdict stream_parser \ + flow_dissector' + COMPREPLY=( $( compgen -W "$BPFTOOL_PROG_ATTACH_TYPES" -- "$cur" ) ) return 0 ;; 6) @@ -464,7 +469,7 @@ _bpftool() case $prev in type) - COMPREPLY=( $( compgen -W "socket kprobe \ + local BPFTOOL_PROG_LOAD_TYPES='socket kprobe \ kretprobe classifier flow_dissector \ action tracepoint raw_tracepoint \ xdp perf_event cgroup/skb cgroup/sock \ @@ -479,8 +484,8 @@ _bpftool() cgroup/post_bind4 cgroup/post_bind6 \ cgroup/sysctl cgroup/getsockopt \ cgroup/setsockopt cgroup/sock_release struct_ops \ - fentry fexit freplace sk_lookup" -- \ - "$cur" ) ) + fentry fexit freplace sk_lookup' + COMPREPLY=( $( compgen -W "$BPFTOOL_PROG_LOAD_TYPES" -- "$cur" ) ) return 0 ;; id) @@ -698,15 +703,15 @@ _bpftool() return 0 ;; type) - COMPREPLY=( $( compgen -W 'hash array prog_array \ - perf_event_array percpu_hash percpu_array \ - stack_trace cgroup_array lru_hash \ + local BPFTOOL_MAP_CREATE_TYPES='hash array \ + prog_array perf_event_array percpu_hash \ + percpu_array stack_trace cgroup_array lru_hash \ lru_percpu_hash lpm_trie array_of_maps \ hash_of_maps devmap devmap_hash sockmap cpumap \ xskmap sockhash cgroup_storage reuseport_sockarray \ percpu_cgroup_storage queue stack sk_storage \ - struct_ops inode_storage task_storage' -- \ - "$cur" ) ) + struct_ops inode_storage task_storage ringbuf' + COMPREPLY=( $( compgen -W "$BPFTOOL_MAP_CREATE_TYPES" -- "$cur" ) ) return 0 ;; key|value|flags|entries) @@ -1017,34 +1022,37 @@ _bpftool() return 0 ;; attach|detach) - local ATTACH_TYPES='ingress egress sock_create sock_ops \ - device bind4 bind6 post_bind4 post_bind6 connect4 connect6 \ + local BPFTOOL_CGROUP_ATTACH_TYPES='ingress egress \ + sock_create sock_ops device \ + bind4 bind6 post_bind4 post_bind6 connect4 connect6 \ getpeername4 getpeername6 getsockname4 getsockname6 \ sendmsg4 sendmsg6 recvmsg4 recvmsg6 sysctl getsockopt \ setsockopt sock_release' local ATTACH_FLAGS='multi override' local PROG_TYPE='id pinned tag name' - case $prev in - $command) - _filedir - return 0 - ;; - ingress|egress|sock_create|sock_ops|device|bind4|bind6|\ - post_bind4|post_bind6|connect4|connect6|getpeername4|\ - getpeername6|getsockname4|getsockname6|sendmsg4|sendmsg6|\ - recvmsg4|recvmsg6|sysctl|getsockopt|setsockopt|sock_release) + # Check for $prev = $command first + if [ $prev = $command ]; then + _filedir + return 0 + # Then check for attach type. This is done outside of the + # "case $prev in" to avoid writing the whole list of attach + # types again as pattern to match (where we cannot reuse + # our variable). + elif [[ $BPFTOOL_CGROUP_ATTACH_TYPES =~ $prev ]]; then COMPREPLY=( $( compgen -W "$PROG_TYPE" -- \ "$cur" ) ) return 0 - ;; + fi + # case/esac for the other cases + case $prev in id) _bpftool_get_prog_ids return 0 ;; *) - if ! _bpftool_search_list "$ATTACH_TYPES"; then - COMPREPLY=( $( compgen -W "$ATTACH_TYPES" -- \ - "$cur" ) ) + if ! _bpftool_search_list "$BPFTOOL_CGROUP_ATTACH_TYPES"; then + COMPREPLY=( $( compgen -W \ + "$BPFTOOL_CGROUP_ATTACH_TYPES" -- "$cur" ) ) elif [[ "$command" == "attach" ]]; then # We have an attach type on the command line, # but it is not the previous word, or diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index 385d5c955cf3..f7e5ff3586c9 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -580,16 +580,12 @@ static int do_dump(int argc, char **argv) } if (!btf) { - err = btf__get_from_id(btf_id, &btf); + btf = btf__load_from_kernel_by_id_split(btf_id, base_btf); + err = libbpf_get_error(btf); if (err) { p_err("get btf by id (%u): %s", btf_id, strerror(err)); goto done; } - if (!btf) { - err = -ENOENT; - p_err("can't find btf with ID (%u)", btf_id); - goto done; - } } if (dump_c) { @@ -985,7 +981,8 @@ static int do_help(int argc, char **argv) " FORMAT := { raw | c }\n" " " HELP_SPEC_MAP "\n" " " HELP_SPEC_PROGRAM "\n" - " " HELP_SPEC_OPTIONS "\n" + " " HELP_SPEC_OPTIONS " |\n" + " {-B|--base-btf} }\n" "", bin_name, "btf"); diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c index 7ca54d046362..9c25286a5c73 100644 --- a/tools/bpf/bpftool/btf_dumper.c +++ b/tools/bpf/bpftool/btf_dumper.c @@ -64,8 +64,10 @@ static int dump_prog_id_as_func_ptr(const struct btf_dumper *d, } info = &prog_info->info; - if (!info->btf_id || !info->nr_func_info || - btf__get_from_id(info->btf_id, &prog_btf)) + if (!info->btf_id || !info->nr_func_info) + goto print; + prog_btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(prog_btf)) goto print; finfo = u64_to_ptr(info->func_info); func_type = btf__type_by_id(prog_btf, finfo->type_id); diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c index 6e53b1d393f4..3571a281c43f 100644 --- a/tools/bpf/bpftool/cgroup.c +++ b/tools/bpf/bpftool/cgroup.c @@ -501,7 +501,8 @@ static int do_help(int argc, char **argv) HELP_SPEC_ATTACH_TYPES "\n" " " HELP_SPEC_ATTACH_FLAGS "\n" " " HELP_SPEC_PROGRAM "\n" - " " HELP_SPEC_OPTIONS "\n" + " " HELP_SPEC_OPTIONS " |\n" + " {-f|--bpffs} }\n" "", bin_name, argv[-2]); diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index dc6daa193557..d42d930a3ec4 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -67,6 +67,12 @@ const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = { [BPF_MODIFY_RETURN] = "mod_ret", [BPF_LSM_MAC] = "lsm_mac", [BPF_SK_LOOKUP] = "sk_lookup", + [BPF_TRACE_ITER] = "trace_iter", + [BPF_XDP_DEVMAP] = "xdp_devmap", + [BPF_XDP_CPUMAP] = "xdp_cpumap", + [BPF_XDP] = "xdp", + [BPF_SK_REUSEPORT_SELECT] = "sk_skb_reuseport_select", + [BPF_SK_REUSEPORT_SELECT_OR_MIGRATE] = "sk_skb_reuseport_select_or_migrate", }; void p_err(const char *fmt, ...) diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index 40a88df275f9..7f36385aa9e2 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -1005,6 +1005,7 @@ static int do_help(int argc, char **argv) " %1$s %2$s help\n" "\n" " COMPONENT := { kernel | dev NAME }\n" + " " HELP_SPEC_OPTIONS " }\n" "", bin_name, argv[-2]); diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 1d71ff8c52fa..d40d92bbf0e4 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -1026,7 +1026,8 @@ static int do_help(int argc, char **argv) " %1$s %2$s skeleton FILE [name OBJECT_NAME]\n" " %1$s %2$s help\n" "\n" - " " HELP_SPEC_OPTIONS "\n" + " " HELP_SPEC_OPTIONS " |\n" + " {-L|--use-loader} }\n" "", bin_name, "gen"); diff --git a/tools/bpf/bpftool/iter.c b/tools/bpf/bpftool/iter.c index 3b1aad7535dd..84a9b01d956d 100644 --- a/tools/bpf/bpftool/iter.c +++ b/tools/bpf/bpftool/iter.c @@ -97,7 +97,9 @@ static int do_help(int argc, char **argv) fprintf(stderr, "Usage: %1$s %2$s pin OBJ PATH [map MAP]\n" " %1$s %2$s help\n" + "\n" " " HELP_SPEC_MAP "\n" + " " HELP_SPEC_OPTIONS " }\n" "", bin_name, "iter"); diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index e77e1525d20a..8cc3e36f8cc6 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -401,7 +401,8 @@ static int do_help(int argc, char **argv) " %1$s %2$s help\n" "\n" " " HELP_SPEC_LINK "\n" - " " HELP_SPEC_OPTIONS "\n" + " " HELP_SPEC_OPTIONS " |\n" + " {-f|--bpffs} | {-n|--nomount} }\n" "", bin_name, argv[-2]); diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 3ddfd4843738..02eaaf065f65 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -64,7 +64,8 @@ static int do_help(int argc, char **argv) " %s version\n" "\n" " OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }\n" - " " HELP_SPEC_OPTIONS "\n" + " " HELP_SPEC_OPTIONS " |\n" + " {-V|--version} }\n" "", bin_name, bin_name, bin_name); diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index c1cf29798b99..90caa42aac4c 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -57,8 +57,7 @@ static inline void *u64_to_ptr(__u64 ptr) #define HELP_SPEC_PROGRAM \ "PROG := { id PROG_ID | pinned FILE | tag PROG_TAG | name PROG_NAME }" #define HELP_SPEC_OPTIONS \ - "OPTIONS := { {-j|--json} [{-p|--pretty}] | {-f|--bpffs} |\n" \ - "\t {-m|--mapcompat} | {-n|--nomount} }" + "OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug}" #define HELP_SPEC_MAP \ "MAP := { id MAP_ID | pinned FILE | name MAP_NAME }" #define HELP_SPEC_LINK \ diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index 09ae0381205b..407071d54ab1 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -807,10 +807,11 @@ static struct btf *get_map_kv_btf(const struct bpf_map_info *info) } else if (info->btf_value_type_id) { int err; - err = btf__get_from_id(info->btf_id, &btf); - if (err || !btf) { + btf = btf__load_from_kernel_by_id(info->btf_id); + err = libbpf_get_error(btf); + if (err) { p_err("failed to get btf"); - btf = err ? ERR_PTR(err) : ERR_PTR(-ESRCH); + btf = ERR_PTR(err); } } @@ -1039,11 +1040,10 @@ static void print_key_value(struct bpf_map_info *info, void *key, void *value) { json_writer_t *btf_wtr; - struct btf *btf = NULL; - int err; + struct btf *btf; - err = btf__get_from_id(info->btf_id, &btf); - if (err) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { p_err("failed to get btf"); return; } @@ -1466,8 +1466,9 @@ static int do_help(int argc, char **argv) " devmap | devmap_hash | sockmap | cpumap | xskmap | sockhash |\n" " cgroup_storage | reuseport_sockarray | percpu_cgroup_storage |\n" " queue | stack | sk_storage | struct_ops | ringbuf | inode_storage |\n" - " task_storage }\n" - " " HELP_SPEC_OPTIONS "\n" + " task_storage }\n" + " " HELP_SPEC_OPTIONS " |\n" + " {-f|--bpffs} | {-n|--nomount} }\n" "", bin_name, argv[-2]); diff --git a/tools/bpf/bpftool/net.c b/tools/bpf/bpftool/net.c index f836d115d7d6..649053704bd7 100644 --- a/tools/bpf/bpftool/net.c +++ b/tools/bpf/bpftool/net.c @@ -729,6 +729,7 @@ static int do_help(int argc, char **argv) "\n" " " HELP_SPEC_PROGRAM "\n" " ATTACH_TYPE := { xdp | xdpgeneric | xdpdrv | xdpoffload }\n" + " " HELP_SPEC_OPTIONS " }\n" "\n" "Note: Only xdp and tc attachments are supported now.\n" " For progs attached to cgroups, use \"bpftool cgroup\"\n" diff --git a/tools/bpf/bpftool/perf.c b/tools/bpf/bpftool/perf.c index ad23934819c7..50de087b0db7 100644 --- a/tools/bpf/bpftool/perf.c +++ b/tools/bpf/bpftool/perf.c @@ -231,7 +231,10 @@ static int do_show(int argc, char **argv) static int do_help(int argc, char **argv) { fprintf(stderr, - "Usage: %1$s %2$s { show | list | help }\n" + "Usage: %1$s %2$s { show | list }\n" + " %1$s %2$s help }\n" + "\n" + " " HELP_SPEC_OPTIONS " }\n" "", bin_name, argv[-2]); diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index cc48726740ad..9c3e343b7d87 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -249,10 +249,10 @@ static void show_prog_metadata(int fd, __u32 num_maps) struct bpf_map_info map_info; struct btf_var_secinfo *vsi; bool printed_header = false; - struct btf *btf = NULL; unsigned int i, vlen; void *value = NULL; const char *name; + struct btf *btf; int err; if (!num_maps) @@ -263,8 +263,8 @@ static void show_prog_metadata(int fd, __u32 num_maps) if (!value) return; - err = btf__get_from_id(map_info.btf_id, &btf); - if (err || !btf) + btf = btf__load_from_kernel_by_id(map_info.btf_id); + if (libbpf_get_error(btf)) goto out_free; t_datasec = btf__type_by_id(btf, map_info.btf_value_type_id); @@ -646,9 +646,12 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, member_len = info->xlated_prog_len; } - if (info->btf_id && btf__get_from_id(info->btf_id, &btf)) { - p_err("failed to get btf"); - return -1; + if (info->btf_id) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { + p_err("failed to get btf"); + return -1; + } } func_info = u64_to_ptr(info->func_info); @@ -781,6 +784,8 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, kernel_syms_destroy(&dd); } + btf__free(btf); + return 0; } @@ -2002,8 +2007,8 @@ static char *profile_target_name(int tgt_fd) struct bpf_prog_info_linear *info_linear; struct bpf_func_info *func_info; const struct btf_type *t; + struct btf *btf = NULL; char *name = NULL; - struct btf *btf; info_linear = bpf_program__get_prog_info_linear( tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO); @@ -2012,12 +2017,17 @@ static char *profile_target_name(int tgt_fd) return NULL; } - if (info_linear->info.btf_id == 0 || - btf__get_from_id(info_linear->info.btf_id, &btf)) { + if (info_linear->info.btf_id == 0) { p_err("prog FD %d doesn't have valid btf", tgt_fd); goto out; } + btf = btf__load_from_kernel_by_id(info_linear->info.btf_id); + if (libbpf_get_error(btf)) { + p_err("failed to load btf for prog FD %d", tgt_fd); + goto out; + } + func_info = u64_to_ptr(info_linear->info.func_info); t = btf__type_by_id(btf, func_info[0].type_id); if (!t) { @@ -2027,6 +2037,7 @@ static char *profile_target_name(int tgt_fd) } name = strdup(btf__name_by_offset(btf, t->name_off)); out: + btf__free(btf); free(info_linear); return name; } @@ -2245,10 +2256,12 @@ static int do_help(int argc, char **argv) " cgroup/sendmsg6 | cgroup/recvmsg4 | cgroup/recvmsg6 |\n" " cgroup/getsockopt | cgroup/setsockopt | cgroup/sock_release |\n" " struct_ops | fentry | fexit | freplace | sk_lookup }\n" - " ATTACH_TYPE := { msg_verdict | stream_verdict | stream_parser |\n" - " flow_dissector }\n" + " ATTACH_TYPE := { msg_verdict | skb_verdict | stream_verdict |\n" + " stream_parser | flow_dissector }\n" " METRIC := { cycles | instructions | l1d_loads | llc_misses | itlb_misses | dtlb_misses }\n" - " " HELP_SPEC_OPTIONS "\n" + " " HELP_SPEC_OPTIONS " |\n" + " {-f|--bpffs} | {-m|--mapcompat} | {-n|--nomount} |\n" + " {-L|--use-loader} }\n" "", bin_name, argv[-2]); diff --git a/tools/bpf/bpftool/struct_ops.c b/tools/bpf/bpftool/struct_ops.c index b58b91f62ffb..ab2d2290569a 100644 --- a/tools/bpf/bpftool/struct_ops.c +++ b/tools/bpf/bpftool/struct_ops.c @@ -572,8 +572,8 @@ static int do_help(int argc, char **argv) " %1$s %2$s unregister STRUCT_OPS_MAP\n" " %1$s %2$s help\n" "\n" - " OPTIONS := { {-j|--json} [{-p|--pretty}] }\n" " STRUCT_OPS_MAP := [ id STRUCT_OPS_MAP_ID | name STRUCT_OPS_MAP_NAME ]\n" + " " HELP_SPEC_OPTIONS " }\n" "", bin_name, argv[-2]); diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c index 3ad9301b0f00..de6365b53c9c 100644 --- a/tools/bpf/resolve_btfids/main.c +++ b/tools/bpf/resolve_btfids/main.c @@ -291,7 +291,7 @@ static int compressed_section_fix(Elf *elf, Elf_Scn *scn, GElf_Shdr *sh) sh->sh_addralign = expected; if (gelf_update_shdr(scn, sh) == 0) { - printf("FAILED cannot update section header: %s\n", + pr_err("FAILED cannot update section header: %s\n", elf_errmsg(-1)); return -1; } @@ -317,6 +317,7 @@ static int elf_collect(struct object *obj) elf = elf_begin(fd, ELF_C_RDWR_MMAP, NULL); if (!elf) { + close(fd); pr_err("FAILED cannot create ELF descriptor: %s\n", elf_errmsg(-1)); return -1; @@ -484,7 +485,7 @@ static int symbols_resolve(struct object *obj) err = libbpf_get_error(btf); if (err) { pr_err("FAILED: load BTF from %s: %s\n", - obj->path, strerror(-err)); + obj->btf ?: obj->path, strerror(-err)); return -1; } @@ -555,8 +556,7 @@ static int id_patch(struct object *obj, struct btf_id *id) int i; if (!id->id) { - pr_err("FAILED unresolved symbol %s\n", id->name); - return -EINVAL; + pr_err("WARN: resolve_btfids: unresolved symbol %s\n", id->name); } for (i = 0; i < id->addr_cnt; i++) { @@ -734,8 +734,9 @@ int main(int argc, const char **argv) err = 0; out: - if (obj.efile.elf) + if (obj.efile.elf) { elf_end(obj.efile.elf); - close(obj.efile.fd); + close(obj.efile.fd); + } return err; } diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build index 430f6874fa41..94f0a146bb7b 100644 --- a/tools/lib/bpf/Build +++ b/tools/lib/bpf/Build @@ -1,3 +1,3 @@ libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o \ netlink.o bpf_prog_linfo.o libbpf_probes.o xsk.o hashmap.o \ - btf_dump.o ringbuf.o strset.o linker.o gen_loader.o + btf_dump.o ringbuf.o strset.o linker.o gen_loader.o relo_core.o diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index b46760b93bb4..85de4fd50699 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -1180,7 +1180,7 @@ int btf__finalize_data(struct bpf_object *obj, struct btf *btf) static void *btf_get_raw_data(const struct btf *btf, __u32 *size, bool swap_endian); -int btf__load(struct btf *btf) +int btf__load_into_kernel(struct btf *btf) { __u32 log_buf_size = 0, raw_size; char *log_buf = NULL; @@ -1228,6 +1228,7 @@ done: free(log_buf); return libbpf_err(err); } +int btf__load(struct btf *) __attribute__((alias("btf__load_into_kernel"))); int btf__fd(const struct btf *btf) { @@ -1382,21 +1383,35 @@ exit_free: return btf; } -int btf__get_from_id(__u32 id, struct btf **btf) +struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf) { - struct btf *res; - int err, btf_fd; + struct btf *btf; + int btf_fd; - *btf = NULL; btf_fd = bpf_btf_get_fd_by_id(id); if (btf_fd < 0) - return libbpf_err(-errno); - - res = btf_get_from_fd(btf_fd, NULL); - err = libbpf_get_error(res); + return libbpf_err_ptr(-errno); + btf = btf_get_from_fd(btf_fd, base_btf); close(btf_fd); + return libbpf_ptr(btf); +} + +struct btf *btf__load_from_kernel_by_id(__u32 id) +{ + return btf__load_from_kernel_by_id_split(id, NULL); +} + +int btf__get_from_id(__u32 id, struct btf **btf) +{ + struct btf *res; + int err; + + *btf = NULL; + res = btf__load_from_kernel_by_id(id); + err = libbpf_get_error(res); + if (err) return libbpf_err(err); @@ -4021,7 +4036,7 @@ static void btf_dedup_merge_hypot_map(struct btf_dedup *d) */ if (d->hypot_adjust_canon) continue; - + if (t_kind == BTF_KIND_FWD && c_kind != BTF_KIND_FWD) d->map[t_id] = c_id; @@ -4394,7 +4409,7 @@ static int btf_dedup_remap_types(struct btf_dedup *d) * Probe few well-known locations for vmlinux kernel image and try to load BTF * data out of it to use for target BTF. */ -struct btf *libbpf_find_kernel_btf(void) +struct btf *btf__load_vmlinux_btf(void) { struct { const char *path_fmt; @@ -4440,6 +4455,16 @@ struct btf *libbpf_find_kernel_btf(void) return libbpf_err_ptr(-ESRCH); } +struct btf *libbpf_find_kernel_btf(void) __attribute__((alias("btf__load_vmlinux_btf"))); + +struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_btf) +{ + char path[80]; + + snprintf(path, sizeof(path), "/sys/kernel/btf/%s", module_name); + return btf__parse_split(path, vmlinux_btf); +} + int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx) { int i, n, err; diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index b54f1c3ebd57..4a711f990904 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -44,8 +44,17 @@ LIBBPF_API struct btf *btf__parse_elf_split(const char *path, struct btf *base_b LIBBPF_API struct btf *btf__parse_raw(const char *path); LIBBPF_API struct btf *btf__parse_raw_split(const char *path, struct btf *base_btf); +LIBBPF_API struct btf *btf__load_vmlinux_btf(void); +LIBBPF_API struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_btf); +LIBBPF_API struct btf *libbpf_find_kernel_btf(void); + +LIBBPF_API struct btf *btf__load_from_kernel_by_id(__u32 id); +LIBBPF_API struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf); +LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf); + LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf); LIBBPF_API int btf__load(struct btf *btf); +LIBBPF_API int btf__load_into_kernel(struct btf *btf); LIBBPF_API __s32 btf__find_by_name(const struct btf *btf, const char *type_name); LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf, @@ -66,7 +75,6 @@ LIBBPF_API void btf__set_fd(struct btf *btf, int fd); LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size); LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset); LIBBPF_API const char *btf__str_by_offset(const struct btf *btf, __u32 offset); -LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf); LIBBPF_API int btf__get_map_kv_tids(const struct btf *btf, const char *map_name, __u32 expected_key_size, __u32 expected_value_size, @@ -89,8 +97,6 @@ int btf_ext__reloc_line_info(const struct btf *btf, LIBBPF_API __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext); LIBBPF_API __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext); -LIBBPF_API struct btf *libbpf_find_kernel_btf(void); - LIBBPF_API int btf__find_str(struct btf *btf, const char *s); LIBBPF_API int btf__add_str(struct btf *btf, const char *s); LIBBPF_API int btf__add_type(struct btf *btf, const struct btf *src_btf, @@ -184,6 +190,25 @@ LIBBPF_API int btf_dump__emit_type_decl(struct btf_dump *d, __u32 id, const struct btf_dump_emit_type_decl_opts *opts); + +struct btf_dump_type_data_opts { + /* size of this struct, for forward/backward compatibility */ + size_t sz; + const char *indent_str; + int indent_level; + /* below match "show" flags for bpf_show_snprintf() */ + bool compact; /* no newlines/indentation */ + bool skip_names; /* skip member/type names */ + bool emit_zeroes; /* show 0-valued fields */ + size_t :0; +}; +#define btf_dump_type_data_opts__last_field emit_zeroes + +LIBBPF_API int +btf_dump__dump_type_data(struct btf_dump *d, __u32 id, + const void *data, size_t data_sz, + const struct btf_dump_type_data_opts *opts); + /* * A set of helpers for easier BTF types handling */ diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index 5dc6b5172bb3..e4b483f15fb9 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -10,6 +10,8 @@ #include <stddef.h> #include <stdlib.h> #include <string.h> +#include <ctype.h> +#include <endian.h> #include <errno.h> #include <linux/err.h> #include <linux/btf.h> @@ -53,6 +55,26 @@ struct btf_dump_type_aux_state { __u8 referenced: 1; }; +/* indent string length; one indent string is added for each indent level */ +#define BTF_DATA_INDENT_STR_LEN 32 + +/* + * Common internal data for BTF type data dump operations. + */ +struct btf_dump_data { + const void *data_end; /* end of valid data to show */ + bool compact; + bool skip_names; + bool emit_zeroes; + __u8 indent_lvl; /* base indent level */ + char indent_str[BTF_DATA_INDENT_STR_LEN]; + /* below are used during iteration */ + int depth; + bool is_array_member; + bool is_array_terminated; + bool is_array_char; +}; + struct btf_dump { const struct btf *btf; const struct btf_ext *btf_ext; @@ -60,6 +82,7 @@ struct btf_dump { struct btf_dump_opts opts; int ptr_sz; bool strip_mods; + bool skip_anon_defs; int last_id; /* per-type auxiliary state */ @@ -89,6 +112,10 @@ struct btf_dump { * name occurrences */ struct hashmap *ident_names; + /* + * data for typed display; allocated if needed. + */ + struct btf_dump_data *typed_dump; }; static size_t str_hash_fn(const void *key, void *ctx) @@ -765,11 +792,11 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id) break; case BTF_KIND_FUNC_PROTO: { const struct btf_param *p = btf_params(t); - __u16 vlen = btf_vlen(t); + __u16 n = btf_vlen(t); int i; btf_dump_emit_type(d, t->type, cont_id); - for (i = 0; i < vlen; i++, p++) + for (i = 0; i < n; i++, p++) btf_dump_emit_type(d, p->type, cont_id); break; @@ -852,8 +879,9 @@ static void btf_dump_emit_bit_padding(const struct btf_dump *d, static void btf_dump_emit_struct_fwd(struct btf_dump *d, __u32 id, const struct btf_type *t) { - btf_dump_printf(d, "%s %s", + btf_dump_printf(d, "%s%s%s", btf_is_struct(t) ? "struct" : "union", + t->name_off ? " " : "", btf_dump_type_name(d, id)); } @@ -1259,7 +1287,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, case BTF_KIND_UNION: btf_dump_emit_mods(d, decls); /* inline anonymous struct/union */ - if (t->name_off == 0) + if (t->name_off == 0 && !d->skip_anon_defs) btf_dump_emit_struct_def(d, id, t, lvl); else btf_dump_emit_struct_fwd(d, id, t); @@ -1267,7 +1295,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, case BTF_KIND_ENUM: btf_dump_emit_mods(d, decls); /* inline anonymous enum */ - if (t->name_off == 0) + if (t->name_off == 0 && !d->skip_anon_defs) btf_dump_emit_enum_def(d, id, t, lvl); else btf_dump_emit_enum_fwd(d, id, t); @@ -1392,6 +1420,39 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, btf_dump_emit_name(d, fname, last_was_ptr); } +/* show type name as (type_name) */ +static void btf_dump_emit_type_cast(struct btf_dump *d, __u32 id, + bool top_level) +{ + const struct btf_type *t; + + /* for array members, we don't bother emitting type name for each + * member to avoid the redundancy of + * .name = (char[4])[(char)'f',(char)'o',(char)'o',] + */ + if (d->typed_dump->is_array_member) + return; + + /* avoid type name specification for variable/section; it will be done + * for the associated variable value(s). + */ + t = btf__type_by_id(d->btf, id); + if (btf_is_var(t) || btf_is_datasec(t)) + return; + + if (top_level) + btf_dump_printf(d, "("); + + d->skip_anon_defs = true; + d->strip_mods = true; + btf_dump_emit_type_decl(d, id, "", 0); + d->strip_mods = false; + d->skip_anon_defs = false; + + if (top_level) + btf_dump_printf(d, ")"); +} + /* return number of duplicates (occurrences) of a given name */ static size_t btf_dump_name_dups(struct btf_dump *d, struct hashmap *name_map, const char *orig_name) @@ -1442,3 +1503,803 @@ static const char *btf_dump_ident_name(struct btf_dump *d, __u32 id) { return btf_dump_resolve_name(d, id, d->ident_names); } + +static int btf_dump_dump_type_data(struct btf_dump *d, + const char *fname, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset, + __u8 bit_sz); + +static const char *btf_dump_data_newline(struct btf_dump *d) +{ + return d->typed_dump->compact || d->typed_dump->depth == 0 ? "" : "\n"; +} + +static const char *btf_dump_data_delim(struct btf_dump *d) +{ + return d->typed_dump->depth == 0 ? "" : ","; +} + +static void btf_dump_data_pfx(struct btf_dump *d) +{ + int i, lvl = d->typed_dump->indent_lvl + d->typed_dump->depth; + + if (d->typed_dump->compact) + return; + + for (i = 0; i < lvl; i++) + btf_dump_printf(d, "%s", d->typed_dump->indent_str); +} + +/* A macro is used here as btf_type_value[s]() appends format specifiers + * to the format specifier passed in; these do the work of appending + * delimiters etc while the caller simply has to specify the type values + * in the format specifier + value(s). + */ +#define btf_dump_type_values(d, fmt, ...) \ + btf_dump_printf(d, fmt "%s%s", \ + ##__VA_ARGS__, \ + btf_dump_data_delim(d), \ + btf_dump_data_newline(d)) + +static int btf_dump_unsupported_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id) +{ + btf_dump_printf(d, "<unsupported kind:%u>", btf_kind(t)); + return -ENOTSUP; +} + +static int btf_dump_get_bitfield_value(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u8 bits_offset, + __u8 bit_sz, + __u64 *value) +{ + __u16 left_shift_bits, right_shift_bits; + __u8 nr_copy_bits, nr_copy_bytes; + const __u8 *bytes = data; + int sz = t->size; + __u64 num = 0; + int i; + + /* Maximum supported bitfield size is 64 bits */ + if (sz > 8) { + pr_warn("unexpected bitfield size %d\n", sz); + return -EINVAL; + } + + /* Bitfield value retrieval is done in two steps; first relevant bytes are + * stored in num, then we left/right shift num to eliminate irrelevant bits. + */ + nr_copy_bits = bit_sz + bits_offset; + nr_copy_bytes = t->size; +#if __BYTE_ORDER == __LITTLE_ENDIAN + for (i = nr_copy_bytes - 1; i >= 0; i--) + num = num * 256 + bytes[i]; +#elif __BYTE_ORDER == __BIG_ENDIAN + for (i = 0; i < nr_copy_bytes; i++) + num = num * 256 + bytes[i]; +#else +# error "Unrecognized __BYTE_ORDER__" +#endif + left_shift_bits = 64 - nr_copy_bits; + right_shift_bits = 64 - bit_sz; + + *value = (num << left_shift_bits) >> right_shift_bits; + + return 0; +} + +static int btf_dump_bitfield_check_zero(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + __u64 check_num; + int err; + + err = btf_dump_get_bitfield_value(d, t, data, bits_offset, bit_sz, &check_num); + if (err) + return err; + if (check_num == 0) + return -ENODATA; + return 0; +} + +static int btf_dump_bitfield_data(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + __u64 print_num; + int err; + + err = btf_dump_get_bitfield_value(d, t, data, bits_offset, bit_sz, &print_num); + if (err) + return err; + + btf_dump_type_values(d, "0x%llx", (unsigned long long)print_num); + + return 0; +} + +/* ints, floats and ptrs */ +static int btf_dump_base_type_check_zero(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + static __u8 bytecmp[16] = {}; + int nr_bytes; + + /* For pointer types, pointer size is not defined on a per-type basis. + * On dump creation however, we store the pointer size. + */ + if (btf_kind(t) == BTF_KIND_PTR) + nr_bytes = d->ptr_sz; + else + nr_bytes = t->size; + + if (nr_bytes < 1 || nr_bytes > 16) { + pr_warn("unexpected size %d for id [%u]\n", nr_bytes, id); + return -EINVAL; + } + + if (memcmp(data, bytecmp, nr_bytes) == 0) + return -ENODATA; + return 0; +} + +static bool ptr_is_aligned(const void *data, int data_sz) +{ + return ((uintptr_t)data) % data_sz == 0; +} + +static int btf_dump_int_data(struct btf_dump *d, + const struct btf_type *t, + __u32 type_id, + const void *data, + __u8 bits_offset) +{ + __u8 encoding = btf_int_encoding(t); + bool sign = encoding & BTF_INT_SIGNED; + int sz = t->size; + + if (sz == 0) { + pr_warn("unexpected size %d for id [%u]\n", sz, type_id); + return -EINVAL; + } + + /* handle packed int data - accesses of integers not aligned on + * int boundaries can cause problems on some platforms. + */ + if (!ptr_is_aligned(data, sz)) + return btf_dump_bitfield_data(d, t, data, 0, 0); + + switch (sz) { + case 16: { + const __u64 *ints = data; + __u64 lsi, msi; + + /* avoid use of __int128 as some 32-bit platforms do not + * support it. + */ +#if __BYTE_ORDER == __LITTLE_ENDIAN + lsi = ints[0]; + msi = ints[1]; +#elif __BYTE_ORDER == __BIG_ENDIAN + lsi = ints[1]; + msi = ints[0]; +#else +# error "Unrecognized __BYTE_ORDER__" +#endif + if (msi == 0) + btf_dump_type_values(d, "0x%llx", (unsigned long long)lsi); + else + btf_dump_type_values(d, "0x%llx%016llx", (unsigned long long)msi, + (unsigned long long)lsi); + break; + } + case 8: + if (sign) + btf_dump_type_values(d, "%lld", *(long long *)data); + else + btf_dump_type_values(d, "%llu", *(unsigned long long *)data); + break; + case 4: + if (sign) + btf_dump_type_values(d, "%d", *(__s32 *)data); + else + btf_dump_type_values(d, "%u", *(__u32 *)data); + break; + case 2: + if (sign) + btf_dump_type_values(d, "%d", *(__s16 *)data); + else + btf_dump_type_values(d, "%u", *(__u16 *)data); + break; + case 1: + if (d->typed_dump->is_array_char) { + /* check for null terminator */ + if (d->typed_dump->is_array_terminated) + break; + if (*(char *)data == '\0') { + d->typed_dump->is_array_terminated = true; + break; + } + if (isprint(*(char *)data)) { + btf_dump_type_values(d, "'%c'", *(char *)data); + break; + } + } + if (sign) + btf_dump_type_values(d, "%d", *(__s8 *)data); + else + btf_dump_type_values(d, "%u", *(__u8 *)data); + break; + default: + pr_warn("unexpected sz %d for id [%u]\n", sz, type_id); + return -EINVAL; + } + return 0; +} + +union float_data { + long double ld; + double d; + float f; +}; + +static int btf_dump_float_data(struct btf_dump *d, + const struct btf_type *t, + __u32 type_id, + const void *data) +{ + const union float_data *flp = data; + union float_data fl; + int sz = t->size; + + /* handle unaligned data; copy to local union */ + if (!ptr_is_aligned(data, sz)) { + memcpy(&fl, data, sz); + flp = &fl; + } + + switch (sz) { + case 16: + btf_dump_type_values(d, "%Lf", flp->ld); + break; + case 8: + btf_dump_type_values(d, "%lf", flp->d); + break; + case 4: + btf_dump_type_values(d, "%f", flp->f); + break; + default: + pr_warn("unexpected size %d for id [%u]\n", sz, type_id); + return -EINVAL; + } + return 0; +} + +static int btf_dump_var_data(struct btf_dump *d, + const struct btf_type *v, + __u32 id, + const void *data) +{ + enum btf_func_linkage linkage = btf_var(v)->linkage; + const struct btf_type *t; + const char *l; + __u32 type_id; + + switch (linkage) { + case BTF_FUNC_STATIC: + l = "static "; + break; + case BTF_FUNC_EXTERN: + l = "extern "; + break; + case BTF_FUNC_GLOBAL: + default: + l = ""; + break; + } + + /* format of output here is [linkage] [type] [varname] = (type)value, + * for example "static int cpu_profile_flip = (int)1" + */ + btf_dump_printf(d, "%s", l); + type_id = v->type; + t = btf__type_by_id(d->btf, type_id); + btf_dump_emit_type_cast(d, type_id, false); + btf_dump_printf(d, " %s = ", btf_name_of(d, v->name_off)); + return btf_dump_dump_type_data(d, NULL, t, type_id, data, 0, 0); +} + +static int btf_dump_array_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_array *array = btf_array(t); + const struct btf_type *elem_type; + __u32 i, elem_size = 0, elem_type_id; + bool is_array_member; + + elem_type_id = array->type; + elem_type = skip_mods_and_typedefs(d->btf, elem_type_id, NULL); + elem_size = btf__resolve_size(d->btf, elem_type_id); + if (elem_size <= 0) { + pr_warn("unexpected elem size %d for array type [%u]\n", elem_size, id); + return -EINVAL; + } + + if (btf_is_int(elem_type)) { + /* + * BTF_INT_CHAR encoding never seems to be set for + * char arrays, so if size is 1 and element is + * printable as a char, we'll do that. + */ + if (elem_size == 1) + d->typed_dump->is_array_char = true; + } + + /* note that we increment depth before calling btf_dump_print() below; + * this is intentional. btf_dump_data_newline() will not print a + * newline for depth 0 (since this leaves us with trailing newlines + * at the end of typed display), so depth is incremented first. + * For similar reasons, we decrement depth before showing the closing + * parenthesis. + */ + d->typed_dump->depth++; + btf_dump_printf(d, "[%s", btf_dump_data_newline(d)); + + /* may be a multidimensional array, so store current "is array member" + * status so we can restore it correctly later. + */ + is_array_member = d->typed_dump->is_array_member; + d->typed_dump->is_array_member = true; + for (i = 0; i < array->nelems; i++, data += elem_size) { + if (d->typed_dump->is_array_terminated) + break; + btf_dump_dump_type_data(d, NULL, elem_type, elem_type_id, data, 0, 0); + } + d->typed_dump->is_array_member = is_array_member; + d->typed_dump->depth--; + btf_dump_data_pfx(d); + btf_dump_type_values(d, "]"); + + return 0; +} + +static int btf_dump_struct_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_member *m = btf_members(t); + __u16 n = btf_vlen(t); + int i, err; + + /* note that we increment depth before calling btf_dump_print() below; + * this is intentional. btf_dump_data_newline() will not print a + * newline for depth 0 (since this leaves us with trailing newlines + * at the end of typed display), so depth is incremented first. + * For similar reasons, we decrement depth before showing the closing + * parenthesis. + */ + d->typed_dump->depth++; + btf_dump_printf(d, "{%s", btf_dump_data_newline(d)); + + for (i = 0; i < n; i++, m++) { + const struct btf_type *mtype; + const char *mname; + __u32 moffset; + __u8 bit_sz; + + mtype = btf__type_by_id(d->btf, m->type); + mname = btf_name_of(d, m->name_off); + moffset = btf_member_bit_offset(t, i); + + bit_sz = btf_member_bitfield_size(t, i); + err = btf_dump_dump_type_data(d, mname, mtype, m->type, data + moffset / 8, + moffset % 8, bit_sz); + if (err < 0) + return err; + } + d->typed_dump->depth--; + btf_dump_data_pfx(d); + btf_dump_type_values(d, "}"); + return err; +} + +union ptr_data { + unsigned int p; + unsigned long long lp; +}; + +static int btf_dump_ptr_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + if (ptr_is_aligned(data, d->ptr_sz) && d->ptr_sz == sizeof(void *)) { + btf_dump_type_values(d, "%p", *(void **)data); + } else { + union ptr_data pt; + + memcpy(&pt, data, d->ptr_sz); + if (d->ptr_sz == 4) + btf_dump_type_values(d, "0x%x", pt.p); + else + btf_dump_type_values(d, "0x%llx", pt.lp); + } + return 0; +} + +static int btf_dump_get_enum_value(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u32 id, + __s64 *value) +{ + int sz = t->size; + + /* handle unaligned enum value */ + if (!ptr_is_aligned(data, sz)) { + __u64 val; + int err; + + err = btf_dump_get_bitfield_value(d, t, data, 0, 0, &val); + if (err) + return err; + *value = (__s64)val; + return 0; + } + + switch (t->size) { + case 8: + *value = *(__s64 *)data; + return 0; + case 4: + *value = *(__s32 *)data; + return 0; + case 2: + *value = *(__s16 *)data; + return 0; + case 1: + *value = *(__s8 *)data; + return 0; + default: + pr_warn("unexpected size %d for enum, id:[%u]\n", t->size, id); + return -EINVAL; + } +} + +static int btf_dump_enum_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_enum *e; + __s64 value; + int i, err; + + err = btf_dump_get_enum_value(d, t, data, id, &value); + if (err) + return err; + + for (i = 0, e = btf_enum(t); i < btf_vlen(t); i++, e++) { + if (value != e->val) + continue; + btf_dump_type_values(d, "%s", btf_name_of(d, e->name_off)); + return 0; + } + + btf_dump_type_values(d, "%d", value); + return 0; +} + +static int btf_dump_datasec_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_var_secinfo *vsi; + const struct btf_type *var; + __u32 i; + int err; + + btf_dump_type_values(d, "SEC(\"%s\") ", btf_name_of(d, t->name_off)); + + for (i = 0, vsi = btf_var_secinfos(t); i < btf_vlen(t); i++, vsi++) { + var = btf__type_by_id(d->btf, vsi->type); + err = btf_dump_dump_type_data(d, NULL, var, vsi->type, data + vsi->offset, 0, 0); + if (err < 0) + return err; + btf_dump_printf(d, ";"); + } + return 0; +} + +/* return size of type, or if base type overflows, return -E2BIG. */ +static int btf_dump_type_data_check_overflow(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset) +{ + __s64 size = btf__resolve_size(d->btf, id); + + if (size < 0 || size >= INT_MAX) { + pr_warn("unexpected size [%zu] for id [%u]\n", + (size_t)size, id); + return -EINVAL; + } + + /* Only do overflow checking for base types; we do not want to + * avoid showing part of a struct, union or array, even if we + * do not have enough data to show the full object. By + * restricting overflow checking to base types we can ensure + * that partial display succeeds, while avoiding overflowing + * and using bogus data for display. + */ + t = skip_mods_and_typedefs(d->btf, id, NULL); + if (!t) { + pr_warn("unexpected error skipping mods/typedefs for id [%u]\n", + id); + return -EINVAL; + } + + switch (btf_kind(t)) { + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_PTR: + case BTF_KIND_ENUM: + if (data + bits_offset / 8 + size > d->typed_dump->data_end) + return -E2BIG; + break; + default: + break; + } + return (int)size; +} + +static int btf_dump_type_data_check_zero(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + __s64 value; + int i, err; + + /* toplevel exceptions; we show zero values if + * - we ask for them (emit_zeros) + * - if we are at top-level so we see "struct empty { }" + * - or if we are an array member and the array is non-empty and + * not a char array; we don't want to be in a situation where we + * have an integer array 0, 1, 0, 1 and only show non-zero values. + * If the array contains zeroes only, or is a char array starting + * with a '\0', the array-level check_zero() will prevent showing it; + * we are concerned with determining zero value at the array member + * level here. + */ + if (d->typed_dump->emit_zeroes || d->typed_dump->depth == 0 || + (d->typed_dump->is_array_member && + !d->typed_dump->is_array_char)) + return 0; + + t = skip_mods_and_typedefs(d->btf, id, NULL); + + switch (btf_kind(t)) { + case BTF_KIND_INT: + if (bit_sz) + return btf_dump_bitfield_check_zero(d, t, data, bits_offset, bit_sz); + return btf_dump_base_type_check_zero(d, t, id, data); + case BTF_KIND_FLOAT: + case BTF_KIND_PTR: + return btf_dump_base_type_check_zero(d, t, id, data); + case BTF_KIND_ARRAY: { + const struct btf_array *array = btf_array(t); + const struct btf_type *elem_type; + __u32 elem_type_id, elem_size; + bool ischar; + + elem_type_id = array->type; + elem_size = btf__resolve_size(d->btf, elem_type_id); + elem_type = skip_mods_and_typedefs(d->btf, elem_type_id, NULL); + + ischar = btf_is_int(elem_type) && elem_size == 1; + + /* check all elements; if _any_ element is nonzero, all + * of array is displayed. We make an exception however + * for char arrays where the first element is 0; these + * are considered zeroed also, even if later elements are + * non-zero because the string is terminated. + */ + for (i = 0; i < array->nelems; i++) { + if (i == 0 && ischar && *(char *)data == 0) + return -ENODATA; + err = btf_dump_type_data_check_zero(d, elem_type, + elem_type_id, + data + + (i * elem_size), + bits_offset, 0); + if (err != -ENODATA) + return err; + } + return -ENODATA; + } + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: { + const struct btf_member *m = btf_members(t); + __u16 n = btf_vlen(t); + + /* if any struct/union member is non-zero, the struct/union + * is considered non-zero and dumped. + */ + for (i = 0; i < n; i++, m++) { + const struct btf_type *mtype; + __u32 moffset; + + mtype = btf__type_by_id(d->btf, m->type); + moffset = btf_member_bit_offset(t, i); + + /* btf_int_bits() does not store member bitfield size; + * bitfield size needs to be stored here so int display + * of member can retrieve it. + */ + bit_sz = btf_member_bitfield_size(t, i); + err = btf_dump_type_data_check_zero(d, mtype, m->type, data + moffset / 8, + moffset % 8, bit_sz); + if (err != ENODATA) + return err; + } + return -ENODATA; + } + case BTF_KIND_ENUM: + err = btf_dump_get_enum_value(d, t, data, id, &value); + if (err) + return err; + if (value == 0) + return -ENODATA; + return 0; + default: + return 0; + } +} + +/* returns size of data dumped, or error. */ +static int btf_dump_dump_type_data(struct btf_dump *d, + const char *fname, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + int size, err; + + size = btf_dump_type_data_check_overflow(d, t, id, data, bits_offset); + if (size < 0) + return size; + err = btf_dump_type_data_check_zero(d, t, id, data, bits_offset, bit_sz); + if (err) { + /* zeroed data is expected and not an error, so simply skip + * dumping such data. Record other errors however. + */ + if (err == -ENODATA) + return size; + return err; + } + btf_dump_data_pfx(d); + + if (!d->typed_dump->skip_names) { + if (fname && strlen(fname) > 0) + btf_dump_printf(d, ".%s = ", fname); + btf_dump_emit_type_cast(d, id, true); + } + + t = skip_mods_and_typedefs(d->btf, id, NULL); + + switch (btf_kind(t)) { + case BTF_KIND_UNKN: + case BTF_KIND_FWD: + case BTF_KIND_FUNC: + case BTF_KIND_FUNC_PROTO: + err = btf_dump_unsupported_data(d, t, id); + break; + case BTF_KIND_INT: + if (bit_sz) + err = btf_dump_bitfield_data(d, t, data, bits_offset, bit_sz); + else + err = btf_dump_int_data(d, t, id, data, bits_offset); + break; + case BTF_KIND_FLOAT: + err = btf_dump_float_data(d, t, id, data); + break; + case BTF_KIND_PTR: + err = btf_dump_ptr_data(d, t, id, data); + break; + case BTF_KIND_ARRAY: + err = btf_dump_array_data(d, t, id, data); + break; + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + err = btf_dump_struct_data(d, t, id, data); + break; + case BTF_KIND_ENUM: + /* handle bitfield and int enum values */ + if (bit_sz) { + __u64 print_num; + __s64 enum_val; + + err = btf_dump_get_bitfield_value(d, t, data, bits_offset, bit_sz, + &print_num); + if (err) + break; + enum_val = (__s64)print_num; + err = btf_dump_enum_data(d, t, id, &enum_val); + } else + err = btf_dump_enum_data(d, t, id, data); + break; + case BTF_KIND_VAR: + err = btf_dump_var_data(d, t, id, data); + break; + case BTF_KIND_DATASEC: + err = btf_dump_datasec_data(d, t, id, data); + break; + default: + pr_warn("unexpected kind [%u] for id [%u]\n", + BTF_INFO_KIND(t->info), id); + return -EINVAL; + } + if (err < 0) + return err; + return size; +} + +int btf_dump__dump_type_data(struct btf_dump *d, __u32 id, + const void *data, size_t data_sz, + const struct btf_dump_type_data_opts *opts) +{ + struct btf_dump_data typed_dump = {}; + const struct btf_type *t; + int ret; + + if (!OPTS_VALID(opts, btf_dump_type_data_opts)) + return libbpf_err(-EINVAL); + + t = btf__type_by_id(d->btf, id); + if (!t) + return libbpf_err(-ENOENT); + + d->typed_dump = &typed_dump; + d->typed_dump->data_end = data + data_sz; + d->typed_dump->indent_lvl = OPTS_GET(opts, indent_level, 0); + + /* default indent string is a tab */ + if (!opts->indent_str) + d->typed_dump->indent_str[0] = '\t'; + else + strncat(d->typed_dump->indent_str, opts->indent_str, + sizeof(d->typed_dump->indent_str) - 1); + + d->typed_dump->compact = OPTS_GET(opts, compact, false); + d->typed_dump->skip_names = OPTS_GET(opts, skip_names, false); + d->typed_dump->emit_zeroes = OPTS_GET(opts, emit_zeroes, false); + + ret = btf_dump_dump_type_data(d, NULL, t, id, data, 0, 0); + + d->typed_dump = NULL; + + return libbpf_err(ret); +} diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 4ccfae30e681..cb106e8c42cb 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -498,6 +498,10 @@ struct bpf_object { * it at load time. */ struct btf *btf_vmlinux; + /* Path to the custom BTF to be used for BPF CO-RE relocations as an + * override for vmlinux BTF. + */ + char *btf_custom_path; /* vmlinux BTF override for CO-RE relocations */ struct btf *btf_vmlinux_override; /* Lazily initialized kernel module BTFs */ @@ -591,11 +595,6 @@ static bool insn_is_subprog_call(const struct bpf_insn *insn) insn->off == 0; } -static bool is_ldimm64_insn(struct bpf_insn *insn) -{ - return insn->code == (BPF_LD | BPF_IMM | BPF_DW); -} - static bool is_call_insn(const struct bpf_insn *insn) { return insn->code == (BPF_JMP | BPF_CALL); @@ -2645,8 +2644,10 @@ static bool obj_needs_vmlinux_btf(const struct bpf_object *obj) struct bpf_program *prog; int i; - /* CO-RE relocations need kernel BTF */ - if (obj->btf_ext && obj->btf_ext->core_relo_info.len) + /* CO-RE relocations need kernel BTF, only when btf_custom_path + * is not specified + */ + if (obj->btf_ext && obj->btf_ext->core_relo_info.len && !obj->btf_custom_path) return true; /* Support for typed ksyms needs kernel BTF */ @@ -2679,7 +2680,7 @@ static int bpf_object__load_vmlinux_btf(struct bpf_object *obj, bool force) if (!force && !obj_needs_vmlinux_btf(obj)) return 0; - obj->btf_vmlinux = libbpf_find_kernel_btf(); + obj->btf_vmlinux = btf__load_vmlinux_btf(); err = libbpf_get_error(obj->btf_vmlinux); if (err) { pr_warn("Error loading vmlinux BTF: %d\n", err); @@ -2768,7 +2769,7 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) */ btf__set_fd(kern_btf, 0); } else { - err = btf__load(kern_btf); + err = btf__load_into_kernel(kern_btf); } if (sanitize) { if (!err) { @@ -4521,6 +4522,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b { struct bpf_create_map_attr create_attr; struct bpf_map_def *def = &map->def; + int err = 0; memset(&create_attr, 0, sizeof(create_attr)); @@ -4563,8 +4565,6 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b if (bpf_map_type__is_map_in_map(def->type)) { if (map->inner_map) { - int err; - err = bpf_object__create_map(obj, map->inner_map, true); if (err) { pr_warn("map '%s': failed to create inner map: %d\n", @@ -4589,8 +4589,8 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b if (map->fd < 0 && (create_attr.btf_key_type_id || create_attr.btf_value_type_id)) { char *cp, errmsg[STRERR_BUFSIZE]; - int err = -errno; + err = -errno; cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); pr_warn("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", map->name, cp, err); @@ -4602,8 +4602,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b map->fd = bpf_create_map_xattr(&create_attr); } - if (map->fd < 0) - return -errno; + err = map->fd < 0 ? -errno : 0; if (bpf_map_type__is_map_in_map(def->type) && map->inner_map) { if (obj->gen_loader) @@ -4612,7 +4611,7 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b zfree(&map->inner_map); } - return 0; + return err; } static int init_map_slots(struct bpf_object *obj, struct bpf_map *map) @@ -4658,10 +4657,13 @@ bpf_object__create_maps(struct bpf_object *obj) char *cp, errmsg[STRERR_BUFSIZE]; unsigned int i, j; int err; + bool retried; for (i = 0; i < obj->nr_maps; i++) { map = &obj->maps[i]; + retried = false; +retry: if (map->pin_path) { err = bpf_object__reuse_map(map); if (err) { @@ -4669,6 +4671,12 @@ bpf_object__create_maps(struct bpf_object *obj) map->name); goto err_out; } + if (retried && map->fd < 0) { + pr_warn("map '%s': cannot find pinned map\n", + map->name); + err = -ENOENT; + goto err_out; + } } if (map->fd >= 0) { @@ -4702,9 +4710,13 @@ bpf_object__create_maps(struct bpf_object *obj) if (map->pin_path && !map->pinned) { err = bpf_map__pin(map, NULL); if (err) { + zclose(map->fd); + if (!retried && err == -EEXIST) { + retried = true; + goto retry; + } pr_warn("map '%s': failed to auto-pin at '%s': %d\n", map->name, map->pin_path, err); - zclose(map->fd); goto err_out; } } @@ -4721,279 +4733,6 @@ err_out: return err; } -#define BPF_CORE_SPEC_MAX_LEN 64 - -/* represents BPF CO-RE field or array element accessor */ -struct bpf_core_accessor { - __u32 type_id; /* struct/union type or array element type */ - __u32 idx; /* field index or array index */ - const char *name; /* field name or NULL for array accessor */ -}; - -struct bpf_core_spec { - const struct btf *btf; - /* high-level spec: named fields and array indices only */ - struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN]; - /* original unresolved (no skip_mods_or_typedefs) root type ID */ - __u32 root_type_id; - /* CO-RE relocation kind */ - enum bpf_core_relo_kind relo_kind; - /* high-level spec length */ - int len; - /* raw, low-level spec: 1-to-1 with accessor spec string */ - int raw_spec[BPF_CORE_SPEC_MAX_LEN]; - /* raw spec length */ - int raw_len; - /* field bit offset represented by spec */ - __u32 bit_offset; -}; - -static bool str_is_empty(const char *s) -{ - return !s || !s[0]; -} - -static bool is_flex_arr(const struct btf *btf, - const struct bpf_core_accessor *acc, - const struct btf_array *arr) -{ - const struct btf_type *t; - - /* not a flexible array, if not inside a struct or has non-zero size */ - if (!acc->name || arr->nelems > 0) - return false; - - /* has to be the last member of enclosing struct */ - t = btf__type_by_id(btf, acc->type_id); - return acc->idx == btf_vlen(t) - 1; -} - -static const char *core_relo_kind_str(enum bpf_core_relo_kind kind) -{ - switch (kind) { - case BPF_FIELD_BYTE_OFFSET: return "byte_off"; - case BPF_FIELD_BYTE_SIZE: return "byte_sz"; - case BPF_FIELD_EXISTS: return "field_exists"; - case BPF_FIELD_SIGNED: return "signed"; - case BPF_FIELD_LSHIFT_U64: return "lshift_u64"; - case BPF_FIELD_RSHIFT_U64: return "rshift_u64"; - case BPF_TYPE_ID_LOCAL: return "local_type_id"; - case BPF_TYPE_ID_TARGET: return "target_type_id"; - case BPF_TYPE_EXISTS: return "type_exists"; - case BPF_TYPE_SIZE: return "type_size"; - case BPF_ENUMVAL_EXISTS: return "enumval_exists"; - case BPF_ENUMVAL_VALUE: return "enumval_value"; - default: return "unknown"; - } -} - -static bool core_relo_is_field_based(enum bpf_core_relo_kind kind) -{ - switch (kind) { - case BPF_FIELD_BYTE_OFFSET: - case BPF_FIELD_BYTE_SIZE: - case BPF_FIELD_EXISTS: - case BPF_FIELD_SIGNED: - case BPF_FIELD_LSHIFT_U64: - case BPF_FIELD_RSHIFT_U64: - return true; - default: - return false; - } -} - -static bool core_relo_is_type_based(enum bpf_core_relo_kind kind) -{ - switch (kind) { - case BPF_TYPE_ID_LOCAL: - case BPF_TYPE_ID_TARGET: - case BPF_TYPE_EXISTS: - case BPF_TYPE_SIZE: - return true; - default: - return false; - } -} - -static bool core_relo_is_enumval_based(enum bpf_core_relo_kind kind) -{ - switch (kind) { - case BPF_ENUMVAL_EXISTS: - case BPF_ENUMVAL_VALUE: - return true; - default: - return false; - } -} - -/* - * Turn bpf_core_relo into a low- and high-level spec representation, - * validating correctness along the way, as well as calculating resulting - * field bit offset, specified by accessor string. Low-level spec captures - * every single level of nestedness, including traversing anonymous - * struct/union members. High-level one only captures semantically meaningful - * "turning points": named fields and array indicies. - * E.g., for this case: - * - * struct sample { - * int __unimportant; - * struct { - * int __1; - * int __2; - * int a[7]; - * }; - * }; - * - * struct sample *s = ...; - * - * int x = &s->a[3]; // access string = '0:1:2:3' - * - * Low-level spec has 1:1 mapping with each element of access string (it's - * just a parsed access string representation): [0, 1, 2, 3]. - * - * High-level spec will capture only 3 points: - * - intial zero-index access by pointer (&s->... is the same as &s[0]...); - * - field 'a' access (corresponds to '2' in low-level spec); - * - array element #3 access (corresponds to '3' in low-level spec). - * - * Type-based relocations (TYPE_EXISTS/TYPE_SIZE, - * TYPE_ID_LOCAL/TYPE_ID_TARGET) don't capture any field information. Their - * spec and raw_spec are kept empty. - * - * Enum value-based relocations (ENUMVAL_EXISTS/ENUMVAL_VALUE) use access - * string to specify enumerator's value index that need to be relocated. - */ -static int bpf_core_parse_spec(const struct btf *btf, - __u32 type_id, - const char *spec_str, - enum bpf_core_relo_kind relo_kind, - struct bpf_core_spec *spec) -{ - int access_idx, parsed_len, i; - struct bpf_core_accessor *acc; - const struct btf_type *t; - const char *name; - __u32 id; - __s64 sz; - - if (str_is_empty(spec_str) || *spec_str == ':') - return -EINVAL; - - memset(spec, 0, sizeof(*spec)); - spec->btf = btf; - spec->root_type_id = type_id; - spec->relo_kind = relo_kind; - - /* type-based relocations don't have a field access string */ - if (core_relo_is_type_based(relo_kind)) { - if (strcmp(spec_str, "0")) - return -EINVAL; - return 0; - } - - /* parse spec_str="0:1:2:3:4" into array raw_spec=[0, 1, 2, 3, 4] */ - while (*spec_str) { - if (*spec_str == ':') - ++spec_str; - if (sscanf(spec_str, "%d%n", &access_idx, &parsed_len) != 1) - return -EINVAL; - if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) - return -E2BIG; - spec_str += parsed_len; - spec->raw_spec[spec->raw_len++] = access_idx; - } - - if (spec->raw_len == 0) - return -EINVAL; - - t = skip_mods_and_typedefs(btf, type_id, &id); - if (!t) - return -EINVAL; - - access_idx = spec->raw_spec[0]; - acc = &spec->spec[0]; - acc->type_id = id; - acc->idx = access_idx; - spec->len++; - - if (core_relo_is_enumval_based(relo_kind)) { - if (!btf_is_enum(t) || spec->raw_len > 1 || access_idx >= btf_vlen(t)) - return -EINVAL; - - /* record enumerator name in a first accessor */ - acc->name = btf__name_by_offset(btf, btf_enum(t)[access_idx].name_off); - return 0; - } - - if (!core_relo_is_field_based(relo_kind)) - return -EINVAL; - - sz = btf__resolve_size(btf, id); - if (sz < 0) - return sz; - spec->bit_offset = access_idx * sz * 8; - - for (i = 1; i < spec->raw_len; i++) { - t = skip_mods_and_typedefs(btf, id, &id); - if (!t) - return -EINVAL; - - access_idx = spec->raw_spec[i]; - acc = &spec->spec[spec->len]; - - if (btf_is_composite(t)) { - const struct btf_member *m; - __u32 bit_offset; - - if (access_idx >= btf_vlen(t)) - return -EINVAL; - - bit_offset = btf_member_bit_offset(t, access_idx); - spec->bit_offset += bit_offset; - - m = btf_members(t) + access_idx; - if (m->name_off) { - name = btf__name_by_offset(btf, m->name_off); - if (str_is_empty(name)) - return -EINVAL; - - acc->type_id = id; - acc->idx = access_idx; - acc->name = name; - spec->len++; - } - - id = m->type; - } else if (btf_is_array(t)) { - const struct btf_array *a = btf_array(t); - bool flex; - - t = skip_mods_and_typedefs(btf, a->type, &id); - if (!t) - return -EINVAL; - - flex = is_flex_arr(btf, acc - 1, a); - if (!flex && access_idx >= a->nelems) - return -EINVAL; - - spec->spec[spec->len].type_id = id; - spec->spec[spec->len].idx = access_idx; - spec->len++; - - sz = btf__resolve_size(btf, id); - if (sz < 0) - return sz; - spec->bit_offset += access_idx * sz * 8; - } else { - pr_warn("relo for [%u] %s (at idx %d) captures type [%d] of unexpected kind %s\n", - type_id, spec_str, i, id, btf_kind_str(t)); - return -EINVAL; - } - } - - return 0; -} - static bool bpf_core_is_flavor_sep(const char *s) { /* check X___Y name pattern, where X and Y are not underscores */ @@ -5006,7 +4745,7 @@ static bool bpf_core_is_flavor_sep(const char *s) * before last triple underscore. Struct name part after last triple * underscore is ignored by BPF CO-RE relocation during relocation matching. */ -static size_t bpf_core_essential_name_len(const char *name) +size_t bpf_core_essential_name_len(const char *name) { size_t n = strlen(name); int i; @@ -5018,34 +4757,20 @@ static size_t bpf_core_essential_name_len(const char *name) return n; } -struct core_cand -{ - const struct btf *btf; - const struct btf_type *t; - const char *name; - __u32 id; -}; - -/* dynamically sized list of type IDs and its associated struct btf */ -struct core_cand_list { - struct core_cand *cands; - int len; -}; - -static void bpf_core_free_cands(struct core_cand_list *cands) +static void bpf_core_free_cands(struct bpf_core_cand_list *cands) { free(cands->cands); free(cands); } -static int bpf_core_add_cands(struct core_cand *local_cand, +static int bpf_core_add_cands(struct bpf_core_cand *local_cand, size_t local_essent_len, const struct btf *targ_btf, const char *targ_btf_name, int targ_start_id, - struct core_cand_list *cands) + struct bpf_core_cand_list *cands) { - struct core_cand *new_cands, *cand; + struct bpf_core_cand *new_cands, *cand; const struct btf_type *t; const char *targ_name; size_t targ_essent_len; @@ -5181,11 +4906,11 @@ err_out: return 0; } -static struct core_cand_list * +static struct bpf_core_cand_list * bpf_core_find_cands(struct bpf_object *obj, const struct btf *local_btf, __u32 local_type_id) { - struct core_cand local_cand = {}; - struct core_cand_list *cands; + struct bpf_core_cand local_cand = {}; + struct bpf_core_cand_list *cands; const struct btf *main_btf; size_t local_essent_len; int err, i; @@ -5239,165 +4964,6 @@ err_out: return ERR_PTR(err); } -/* Check two types for compatibility for the purpose of field access - * relocation. const/volatile/restrict and typedefs are skipped to ensure we - * are relocating semantically compatible entities: - * - any two STRUCTs/UNIONs are compatible and can be mixed; - * - any two FWDs are compatible, if their names match (modulo flavor suffix); - * - any two PTRs are always compatible; - * - for ENUMs, names should be the same (ignoring flavor suffix) or at - * least one of enums should be anonymous; - * - for ENUMs, check sizes, names are ignored; - * - for INT, size and signedness are ignored; - * - any two FLOATs are always compatible; - * - for ARRAY, dimensionality is ignored, element types are checked for - * compatibility recursively; - * - everything else shouldn't be ever a target of relocation. - * These rules are not set in stone and probably will be adjusted as we get - * more experience with using BPF CO-RE relocations. - */ -static int bpf_core_fields_are_compat(const struct btf *local_btf, - __u32 local_id, - const struct btf *targ_btf, - __u32 targ_id) -{ - const struct btf_type *local_type, *targ_type; - -recur: - local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); - targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); - if (!local_type || !targ_type) - return -EINVAL; - - if (btf_is_composite(local_type) && btf_is_composite(targ_type)) - return 1; - if (btf_kind(local_type) != btf_kind(targ_type)) - return 0; - - switch (btf_kind(local_type)) { - case BTF_KIND_PTR: - case BTF_KIND_FLOAT: - return 1; - case BTF_KIND_FWD: - case BTF_KIND_ENUM: { - const char *local_name, *targ_name; - size_t local_len, targ_len; - - local_name = btf__name_by_offset(local_btf, - local_type->name_off); - targ_name = btf__name_by_offset(targ_btf, targ_type->name_off); - local_len = bpf_core_essential_name_len(local_name); - targ_len = bpf_core_essential_name_len(targ_name); - /* one of them is anonymous or both w/ same flavor-less names */ - return local_len == 0 || targ_len == 0 || - (local_len == targ_len && - strncmp(local_name, targ_name, local_len) == 0); - } - case BTF_KIND_INT: - /* just reject deprecated bitfield-like integers; all other - * integers are by default compatible between each other - */ - return btf_int_offset(local_type) == 0 && - btf_int_offset(targ_type) == 0; - case BTF_KIND_ARRAY: - local_id = btf_array(local_type)->type; - targ_id = btf_array(targ_type)->type; - goto recur; - default: - pr_warn("unexpected kind %d relocated, local [%d], target [%d]\n", - btf_kind(local_type), local_id, targ_id); - return 0; - } -} - -/* - * Given single high-level named field accessor in local type, find - * corresponding high-level accessor for a target type. Along the way, - * maintain low-level spec for target as well. Also keep updating target - * bit offset. - * - * Searching is performed through recursive exhaustive enumeration of all - * fields of a struct/union. If there are any anonymous (embedded) - * structs/unions, they are recursively searched as well. If field with - * desired name is found, check compatibility between local and target types, - * before returning result. - * - * 1 is returned, if field is found. - * 0 is returned if no compatible field is found. - * <0 is returned on error. - */ -static int bpf_core_match_member(const struct btf *local_btf, - const struct bpf_core_accessor *local_acc, - const struct btf *targ_btf, - __u32 targ_id, - struct bpf_core_spec *spec, - __u32 *next_targ_id) -{ - const struct btf_type *local_type, *targ_type; - const struct btf_member *local_member, *m; - const char *local_name, *targ_name; - __u32 local_id; - int i, n, found; - - targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); - if (!targ_type) - return -EINVAL; - if (!btf_is_composite(targ_type)) - return 0; - - local_id = local_acc->type_id; - local_type = btf__type_by_id(local_btf, local_id); - local_member = btf_members(local_type) + local_acc->idx; - local_name = btf__name_by_offset(local_btf, local_member->name_off); - - n = btf_vlen(targ_type); - m = btf_members(targ_type); - for (i = 0; i < n; i++, m++) { - __u32 bit_offset; - - bit_offset = btf_member_bit_offset(targ_type, i); - - /* too deep struct/union/array nesting */ - if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) - return -E2BIG; - - /* speculate this member will be the good one */ - spec->bit_offset += bit_offset; - spec->raw_spec[spec->raw_len++] = i; - - targ_name = btf__name_by_offset(targ_btf, m->name_off); - if (str_is_empty(targ_name)) { - /* embedded struct/union, we need to go deeper */ - found = bpf_core_match_member(local_btf, local_acc, - targ_btf, m->type, - spec, next_targ_id); - if (found) /* either found or error */ - return found; - } else if (strcmp(local_name, targ_name) == 0) { - /* matching named field */ - struct bpf_core_accessor *targ_acc; - - targ_acc = &spec->spec[spec->len++]; - targ_acc->type_id = targ_id; - targ_acc->idx = i; - targ_acc->name = targ_name; - - *next_targ_id = m->type; - found = bpf_core_fields_are_compat(local_btf, - local_member->type, - targ_btf, m->type); - if (!found) - spec->len--; /* pop accessor */ - return found; - } - /* member turned out not to be what we looked for */ - spec->bit_offset -= bit_offset; - spec->raw_len--; - } - - return 0; -} - /* Check local and target types for compatibility. This check is used for * type-based CO-RE relocations and follow slightly different rules than * field-based relocations. This function assumes that root types were already @@ -5417,8 +4983,8 @@ static int bpf_core_match_member(const struct btf *local_btf, * These rules are not set in stone and probably will be adjusted as we get * more experience with using BPF CO-RE relocations. */ -static int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, - const struct btf *targ_btf, __u32 targ_id) +int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, + const struct btf *targ_btf, __u32 targ_id) { const struct btf_type *local_type, *targ_type; int depth = 32; /* max recursion depth */ @@ -5492,671 +5058,6 @@ recur: } } -/* - * Try to match local spec to a target type and, if successful, produce full - * target spec (high-level, low-level + bit offset). - */ -static int bpf_core_spec_match(struct bpf_core_spec *local_spec, - const struct btf *targ_btf, __u32 targ_id, - struct bpf_core_spec *targ_spec) -{ - const struct btf_type *targ_type; - const struct bpf_core_accessor *local_acc; - struct bpf_core_accessor *targ_acc; - int i, sz, matched; - - memset(targ_spec, 0, sizeof(*targ_spec)); - targ_spec->btf = targ_btf; - targ_spec->root_type_id = targ_id; - targ_spec->relo_kind = local_spec->relo_kind; - - if (core_relo_is_type_based(local_spec->relo_kind)) { - return bpf_core_types_are_compat(local_spec->btf, - local_spec->root_type_id, - targ_btf, targ_id); - } - - local_acc = &local_spec->spec[0]; - targ_acc = &targ_spec->spec[0]; - - if (core_relo_is_enumval_based(local_spec->relo_kind)) { - size_t local_essent_len, targ_essent_len; - const struct btf_enum *e; - const char *targ_name; - - /* has to resolve to an enum */ - targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, &targ_id); - if (!btf_is_enum(targ_type)) - return 0; - - local_essent_len = bpf_core_essential_name_len(local_acc->name); - - for (i = 0, e = btf_enum(targ_type); i < btf_vlen(targ_type); i++, e++) { - targ_name = btf__name_by_offset(targ_spec->btf, e->name_off); - targ_essent_len = bpf_core_essential_name_len(targ_name); - if (targ_essent_len != local_essent_len) - continue; - if (strncmp(local_acc->name, targ_name, local_essent_len) == 0) { - targ_acc->type_id = targ_id; - targ_acc->idx = i; - targ_acc->name = targ_name; - targ_spec->len++; - targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; - targ_spec->raw_len++; - return 1; - } - } - return 0; - } - - if (!core_relo_is_field_based(local_spec->relo_kind)) - return -EINVAL; - - for (i = 0; i < local_spec->len; i++, local_acc++, targ_acc++) { - targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, - &targ_id); - if (!targ_type) - return -EINVAL; - - if (local_acc->name) { - matched = bpf_core_match_member(local_spec->btf, - local_acc, - targ_btf, targ_id, - targ_spec, &targ_id); - if (matched <= 0) - return matched; - } else { - /* for i=0, targ_id is already treated as array element - * type (because it's the original struct), for others - * we should find array element type first - */ - if (i > 0) { - const struct btf_array *a; - bool flex; - - if (!btf_is_array(targ_type)) - return 0; - - a = btf_array(targ_type); - flex = is_flex_arr(targ_btf, targ_acc - 1, a); - if (!flex && local_acc->idx >= a->nelems) - return 0; - if (!skip_mods_and_typedefs(targ_btf, a->type, - &targ_id)) - return -EINVAL; - } - - /* too deep struct/union/array nesting */ - if (targ_spec->raw_len == BPF_CORE_SPEC_MAX_LEN) - return -E2BIG; - - targ_acc->type_id = targ_id; - targ_acc->idx = local_acc->idx; - targ_acc->name = NULL; - targ_spec->len++; - targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; - targ_spec->raw_len++; - - sz = btf__resolve_size(targ_btf, targ_id); - if (sz < 0) - return sz; - targ_spec->bit_offset += local_acc->idx * sz * 8; - } - } - - return 1; -} - -static int bpf_core_calc_field_relo(const struct bpf_program *prog, - const struct bpf_core_relo *relo, - const struct bpf_core_spec *spec, - __u32 *val, __u32 *field_sz, __u32 *type_id, - bool *validate) -{ - const struct bpf_core_accessor *acc; - const struct btf_type *t; - __u32 byte_off, byte_sz, bit_off, bit_sz, field_type_id; - const struct btf_member *m; - const struct btf_type *mt; - bool bitfield; - __s64 sz; - - *field_sz = 0; - - if (relo->kind == BPF_FIELD_EXISTS) { - *val = spec ? 1 : 0; - return 0; - } - - if (!spec) - return -EUCLEAN; /* request instruction poisoning */ - - acc = &spec->spec[spec->len - 1]; - t = btf__type_by_id(spec->btf, acc->type_id); - - /* a[n] accessor needs special handling */ - if (!acc->name) { - if (relo->kind == BPF_FIELD_BYTE_OFFSET) { - *val = spec->bit_offset / 8; - /* remember field size for load/store mem size */ - sz = btf__resolve_size(spec->btf, acc->type_id); - if (sz < 0) - return -EINVAL; - *field_sz = sz; - *type_id = acc->type_id; - } else if (relo->kind == BPF_FIELD_BYTE_SIZE) { - sz = btf__resolve_size(spec->btf, acc->type_id); - if (sz < 0) - return -EINVAL; - *val = sz; - } else { - pr_warn("prog '%s': relo %d at insn #%d can't be applied to array access\n", - prog->name, relo->kind, relo->insn_off / 8); - return -EINVAL; - } - if (validate) - *validate = true; - return 0; - } - - m = btf_members(t) + acc->idx; - mt = skip_mods_and_typedefs(spec->btf, m->type, &field_type_id); - bit_off = spec->bit_offset; - bit_sz = btf_member_bitfield_size(t, acc->idx); - - bitfield = bit_sz > 0; - if (bitfield) { - byte_sz = mt->size; - byte_off = bit_off / 8 / byte_sz * byte_sz; - /* figure out smallest int size necessary for bitfield load */ - while (bit_off + bit_sz - byte_off * 8 > byte_sz * 8) { - if (byte_sz >= 8) { - /* bitfield can't be read with 64-bit read */ - pr_warn("prog '%s': relo %d at insn #%d can't be satisfied for bitfield\n", - prog->name, relo->kind, relo->insn_off / 8); - return -E2BIG; - } - byte_sz *= 2; - byte_off = bit_off / 8 / byte_sz * byte_sz; - } - } else { - sz = btf__resolve_size(spec->btf, field_type_id); - if (sz < 0) - return -EINVAL; - byte_sz = sz; - byte_off = spec->bit_offset / 8; - bit_sz = byte_sz * 8; - } - - /* for bitfields, all the relocatable aspects are ambiguous and we - * might disagree with compiler, so turn off validation of expected - * value, except for signedness - */ - if (validate) - *validate = !bitfield; - - switch (relo->kind) { - case BPF_FIELD_BYTE_OFFSET: - *val = byte_off; - if (!bitfield) { - *field_sz = byte_sz; - *type_id = field_type_id; - } - break; - case BPF_FIELD_BYTE_SIZE: - *val = byte_sz; - break; - case BPF_FIELD_SIGNED: - /* enums will be assumed unsigned */ - *val = btf_is_enum(mt) || - (btf_int_encoding(mt) & BTF_INT_SIGNED); - if (validate) - *validate = true; /* signedness is never ambiguous */ - break; - case BPF_FIELD_LSHIFT_U64: -#if __BYTE_ORDER == __LITTLE_ENDIAN - *val = 64 - (bit_off + bit_sz - byte_off * 8); -#else - *val = (8 - byte_sz) * 8 + (bit_off - byte_off * 8); -#endif - break; - case BPF_FIELD_RSHIFT_U64: - *val = 64 - bit_sz; - if (validate) - *validate = true; /* right shift is never ambiguous */ - break; - case BPF_FIELD_EXISTS: - default: - return -EOPNOTSUPP; - } - - return 0; -} - -static int bpf_core_calc_type_relo(const struct bpf_core_relo *relo, - const struct bpf_core_spec *spec, - __u32 *val) -{ - __s64 sz; - - /* type-based relos return zero when target type is not found */ - if (!spec) { - *val = 0; - return 0; - } - - switch (relo->kind) { - case BPF_TYPE_ID_TARGET: - *val = spec->root_type_id; - break; - case BPF_TYPE_EXISTS: - *val = 1; - break; - case BPF_TYPE_SIZE: - sz = btf__resolve_size(spec->btf, spec->root_type_id); - if (sz < 0) - return -EINVAL; - *val = sz; - break; - case BPF_TYPE_ID_LOCAL: - /* BPF_TYPE_ID_LOCAL is handled specially and shouldn't get here */ - default: - return -EOPNOTSUPP; - } - - return 0; -} - -static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo, - const struct bpf_core_spec *spec, - __u32 *val) -{ - const struct btf_type *t; - const struct btf_enum *e; - - switch (relo->kind) { - case BPF_ENUMVAL_EXISTS: - *val = spec ? 1 : 0; - break; - case BPF_ENUMVAL_VALUE: - if (!spec) - return -EUCLEAN; /* request instruction poisoning */ - t = btf__type_by_id(spec->btf, spec->spec[0].type_id); - e = btf_enum(t) + spec->spec[0].idx; - *val = e->val; - break; - default: - return -EOPNOTSUPP; - } - - return 0; -} - -struct bpf_core_relo_res -{ - /* expected value in the instruction, unless validate == false */ - __u32 orig_val; - /* new value that needs to be patched up to */ - __u32 new_val; - /* relocation unsuccessful, poison instruction, but don't fail load */ - bool poison; - /* some relocations can't be validated against orig_val */ - bool validate; - /* for field byte offset relocations or the forms: - * *(T *)(rX + <off>) = rY - * rX = *(T *)(rY + <off>), - * we remember original and resolved field size to adjust direct - * memory loads of pointers and integers; this is necessary for 32-bit - * host kernel architectures, but also allows to automatically - * relocate fields that were resized from, e.g., u32 to u64, etc. - */ - bool fail_memsz_adjust; - __u32 orig_sz; - __u32 orig_type_id; - __u32 new_sz; - __u32 new_type_id; -}; - -/* Calculate original and target relocation values, given local and target - * specs and relocation kind. These values are calculated for each candidate. - * If there are multiple candidates, resulting values should all be consistent - * with each other. Otherwise, libbpf will refuse to proceed due to ambiguity. - * If instruction has to be poisoned, *poison will be set to true. - */ -static int bpf_core_calc_relo(const struct bpf_program *prog, - const struct bpf_core_relo *relo, - int relo_idx, - const struct bpf_core_spec *local_spec, - const struct bpf_core_spec *targ_spec, - struct bpf_core_relo_res *res) -{ - int err = -EOPNOTSUPP; - - res->orig_val = 0; - res->new_val = 0; - res->poison = false; - res->validate = true; - res->fail_memsz_adjust = false; - res->orig_sz = res->new_sz = 0; - res->orig_type_id = res->new_type_id = 0; - - if (core_relo_is_field_based(relo->kind)) { - err = bpf_core_calc_field_relo(prog, relo, local_spec, - &res->orig_val, &res->orig_sz, - &res->orig_type_id, &res->validate); - err = err ?: bpf_core_calc_field_relo(prog, relo, targ_spec, - &res->new_val, &res->new_sz, - &res->new_type_id, NULL); - if (err) - goto done; - /* Validate if it's safe to adjust load/store memory size. - * Adjustments are performed only if original and new memory - * sizes differ. - */ - res->fail_memsz_adjust = false; - if (res->orig_sz != res->new_sz) { - const struct btf_type *orig_t, *new_t; - - orig_t = btf__type_by_id(local_spec->btf, res->orig_type_id); - new_t = btf__type_by_id(targ_spec->btf, res->new_type_id); - - /* There are two use cases in which it's safe to - * adjust load/store's mem size: - * - reading a 32-bit kernel pointer, while on BPF - * size pointers are always 64-bit; in this case - * it's safe to "downsize" instruction size due to - * pointer being treated as unsigned integer with - * zero-extended upper 32-bits; - * - reading unsigned integers, again due to - * zero-extension is preserving the value correctly. - * - * In all other cases it's incorrect to attempt to - * load/store field because read value will be - * incorrect, so we poison relocated instruction. - */ - if (btf_is_ptr(orig_t) && btf_is_ptr(new_t)) - goto done; - if (btf_is_int(orig_t) && btf_is_int(new_t) && - btf_int_encoding(orig_t) != BTF_INT_SIGNED && - btf_int_encoding(new_t) != BTF_INT_SIGNED) - goto done; - - /* mark as invalid mem size adjustment, but this will - * only be checked for LDX/STX/ST insns - */ - res->fail_memsz_adjust = true; - } - } else if (core_relo_is_type_based(relo->kind)) { - err = bpf_core_calc_type_relo(relo, local_spec, &res->orig_val); - err = err ?: bpf_core_calc_type_relo(relo, targ_spec, &res->new_val); - } else if (core_relo_is_enumval_based(relo->kind)) { - err = bpf_core_calc_enumval_relo(relo, local_spec, &res->orig_val); - err = err ?: bpf_core_calc_enumval_relo(relo, targ_spec, &res->new_val); - } - -done: - if (err == -EUCLEAN) { - /* EUCLEAN is used to signal instruction poisoning request */ - res->poison = true; - err = 0; - } else if (err == -EOPNOTSUPP) { - /* EOPNOTSUPP means unknown/unsupported relocation */ - pr_warn("prog '%s': relo #%d: unrecognized CO-RE relocation %s (%d) at insn #%d\n", - prog->name, relo_idx, core_relo_kind_str(relo->kind), - relo->kind, relo->insn_off / 8); - } - - return err; -} - -/* - * Turn instruction for which CO_RE relocation failed into invalid one with - * distinct signature. - */ -static void bpf_core_poison_insn(struct bpf_program *prog, int relo_idx, - int insn_idx, struct bpf_insn *insn) -{ - pr_debug("prog '%s': relo #%d: substituting insn #%d w/ invalid insn\n", - prog->name, relo_idx, insn_idx); - insn->code = BPF_JMP | BPF_CALL; - insn->dst_reg = 0; - insn->src_reg = 0; - insn->off = 0; - /* if this instruction is reachable (not a dead code), - * verifier will complain with the following message: - * invalid func unknown#195896080 - */ - insn->imm = 195896080; /* => 0xbad2310 => "bad relo" */ -} - -static int insn_bpf_size_to_bytes(struct bpf_insn *insn) -{ - switch (BPF_SIZE(insn->code)) { - case BPF_DW: return 8; - case BPF_W: return 4; - case BPF_H: return 2; - case BPF_B: return 1; - default: return -1; - } -} - -static int insn_bytes_to_bpf_size(__u32 sz) -{ - switch (sz) { - case 8: return BPF_DW; - case 4: return BPF_W; - case 2: return BPF_H; - case 1: return BPF_B; - default: return -1; - } -} - -/* - * Patch relocatable BPF instruction. - * - * Patched value is determined by relocation kind and target specification. - * For existence relocations target spec will be NULL if field/type is not found. - * Expected insn->imm value is determined using relocation kind and local - * spec, and is checked before patching instruction. If actual insn->imm value - * is wrong, bail out with error. - * - * Currently supported classes of BPF instruction are: - * 1. rX = <imm> (assignment with immediate operand); - * 2. rX += <imm> (arithmetic operations with immediate operand); - * 3. rX = <imm64> (load with 64-bit immediate value); - * 4. rX = *(T *)(rY + <off>), where T is one of {u8, u16, u32, u64}; - * 5. *(T *)(rX + <off>) = rY, where T is one of {u8, u16, u32, u64}; - * 6. *(T *)(rX + <off>) = <imm>, where T is one of {u8, u16, u32, u64}. - */ -static int bpf_core_patch_insn(struct bpf_program *prog, - const struct bpf_core_relo *relo, - int relo_idx, - const struct bpf_core_relo_res *res) -{ - __u32 orig_val, new_val; - struct bpf_insn *insn; - int insn_idx; - __u8 class; - - if (relo->insn_off % BPF_INSN_SZ) - return -EINVAL; - insn_idx = relo->insn_off / BPF_INSN_SZ; - /* adjust insn_idx from section frame of reference to the local - * program's frame of reference; (sub-)program code is not yet - * relocated, so it's enough to just subtract in-section offset - */ - insn_idx = insn_idx - prog->sec_insn_off; - insn = &prog->insns[insn_idx]; - class = BPF_CLASS(insn->code); - - if (res->poison) { -poison: - /* poison second part of ldimm64 to avoid confusing error from - * verifier about "unknown opcode 00" - */ - if (is_ldimm64_insn(insn)) - bpf_core_poison_insn(prog, relo_idx, insn_idx + 1, insn + 1); - bpf_core_poison_insn(prog, relo_idx, insn_idx, insn); - return 0; - } - - orig_val = res->orig_val; - new_val = res->new_val; - - switch (class) { - case BPF_ALU: - case BPF_ALU64: - if (BPF_SRC(insn->code) != BPF_K) - return -EINVAL; - if (res->validate && insn->imm != orig_val) { - pr_warn("prog '%s': relo #%d: unexpected insn #%d (ALU/ALU64) value: got %u, exp %u -> %u\n", - prog->name, relo_idx, - insn_idx, insn->imm, orig_val, new_val); - return -EINVAL; - } - orig_val = insn->imm; - insn->imm = new_val; - pr_debug("prog '%s': relo #%d: patched insn #%d (ALU/ALU64) imm %u -> %u\n", - prog->name, relo_idx, insn_idx, - orig_val, new_val); - break; - case BPF_LDX: - case BPF_ST: - case BPF_STX: - if (res->validate && insn->off != orig_val) { - pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDX/ST/STX) value: got %u, exp %u -> %u\n", - prog->name, relo_idx, insn_idx, insn->off, orig_val, new_val); - return -EINVAL; - } - if (new_val > SHRT_MAX) { - pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) value too big: %u\n", - prog->name, relo_idx, insn_idx, new_val); - return -ERANGE; - } - if (res->fail_memsz_adjust) { - pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) accesses field incorrectly. " - "Make sure you are accessing pointers, unsigned integers, or fields of matching type and size.\n", - prog->name, relo_idx, insn_idx); - goto poison; - } - - orig_val = insn->off; - insn->off = new_val; - pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) off %u -> %u\n", - prog->name, relo_idx, insn_idx, orig_val, new_val); - - if (res->new_sz != res->orig_sz) { - int insn_bytes_sz, insn_bpf_sz; - - insn_bytes_sz = insn_bpf_size_to_bytes(insn); - if (insn_bytes_sz != res->orig_sz) { - pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) unexpected mem size: got %d, exp %u\n", - prog->name, relo_idx, insn_idx, insn_bytes_sz, res->orig_sz); - return -EINVAL; - } - - insn_bpf_sz = insn_bytes_to_bpf_size(res->new_sz); - if (insn_bpf_sz < 0) { - pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) invalid new mem size: %u\n", - prog->name, relo_idx, insn_idx, res->new_sz); - return -EINVAL; - } - - insn->code = BPF_MODE(insn->code) | insn_bpf_sz | BPF_CLASS(insn->code); - pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) mem_sz %u -> %u\n", - prog->name, relo_idx, insn_idx, res->orig_sz, res->new_sz); - } - break; - case BPF_LD: { - __u64 imm; - - if (!is_ldimm64_insn(insn) || - insn[0].src_reg != 0 || insn[0].off != 0 || - insn_idx + 1 >= prog->insns_cnt || - insn[1].code != 0 || insn[1].dst_reg != 0 || - insn[1].src_reg != 0 || insn[1].off != 0) { - pr_warn("prog '%s': relo #%d: insn #%d (LDIMM64) has unexpected form\n", - prog->name, relo_idx, insn_idx); - return -EINVAL; - } - - imm = insn[0].imm + ((__u64)insn[1].imm << 32); - if (res->validate && imm != orig_val) { - pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDIMM64) value: got %llu, exp %u -> %u\n", - prog->name, relo_idx, - insn_idx, (unsigned long long)imm, - orig_val, new_val); - return -EINVAL; - } - - insn[0].imm = new_val; - insn[1].imm = 0; /* currently only 32-bit values are supported */ - pr_debug("prog '%s': relo #%d: patched insn #%d (LDIMM64) imm64 %llu -> %u\n", - prog->name, relo_idx, insn_idx, - (unsigned long long)imm, new_val); - break; - } - default: - pr_warn("prog '%s': relo #%d: trying to relocate unrecognized insn #%d, code:0x%x, src:0x%x, dst:0x%x, off:0x%x, imm:0x%x\n", - prog->name, relo_idx, insn_idx, insn->code, - insn->src_reg, insn->dst_reg, insn->off, insn->imm); - return -EINVAL; - } - - return 0; -} - -/* Output spec definition in the format: - * [<type-id>] (<type-name>) + <raw-spec> => <offset>@<spec>, - * where <spec> is a C-syntax view of recorded field access, e.g.: x.a[3].b - */ -static void bpf_core_dump_spec(int level, const struct bpf_core_spec *spec) -{ - const struct btf_type *t; - const struct btf_enum *e; - const char *s; - __u32 type_id; - int i; - - type_id = spec->root_type_id; - t = btf__type_by_id(spec->btf, type_id); - s = btf__name_by_offset(spec->btf, t->name_off); - - libbpf_print(level, "[%u] %s %s", type_id, btf_kind_str(t), str_is_empty(s) ? "<anon>" : s); - - if (core_relo_is_type_based(spec->relo_kind)) - return; - - if (core_relo_is_enumval_based(spec->relo_kind)) { - t = skip_mods_and_typedefs(spec->btf, type_id, NULL); - e = btf_enum(t) + spec->raw_spec[0]; - s = btf__name_by_offset(spec->btf, e->name_off); - - libbpf_print(level, "::%s = %u", s, e->val); - return; - } - - if (core_relo_is_field_based(spec->relo_kind)) { - for (i = 0; i < spec->len; i++) { - if (spec->spec[i].name) - libbpf_print(level, ".%s", spec->spec[i].name); - else if (i > 0 || spec->spec[i].idx > 0) - libbpf_print(level, "[%u]", spec->spec[i].idx); - } - - libbpf_print(level, " ("); - for (i = 0; i < spec->raw_len; i++) - libbpf_print(level, "%s%d", i == 0 ? "" : ":", spec->raw_spec[i]); - - if (spec->bit_offset % 8) - libbpf_print(level, " @ offset %u.%u)", - spec->bit_offset / 8, spec->bit_offset % 8); - else - libbpf_print(level, " @ offset %u)", spec->bit_offset / 8); - return; - } -} - static size_t bpf_core_hash_fn(const void *key, void *ctx) { return (size_t)key; @@ -6172,73 +5073,33 @@ static void *u32_as_hash_key(__u32 x) return (void *)(uintptr_t)x; } -/* - * CO-RE relocate single instruction. - * - * The outline and important points of the algorithm: - * 1. For given local type, find corresponding candidate target types. - * Candidate type is a type with the same "essential" name, ignoring - * everything after last triple underscore (___). E.g., `sample`, - * `sample___flavor_one`, `sample___flavor_another_one`, are all candidates - * for each other. Names with triple underscore are referred to as - * "flavors" and are useful, among other things, to allow to - * specify/support incompatible variations of the same kernel struct, which - * might differ between different kernel versions and/or build - * configurations. - * - * N.B. Struct "flavors" could be generated by bpftool's BTF-to-C - * converter, when deduplicated BTF of a kernel still contains more than - * one different types with the same name. In that case, ___2, ___3, etc - * are appended starting from second name conflict. But start flavors are - * also useful to be defined "locally", in BPF program, to extract same - * data from incompatible changes between different kernel - * versions/configurations. For instance, to handle field renames between - * kernel versions, one can use two flavors of the struct name with the - * same common name and use conditional relocations to extract that field, - * depending on target kernel version. - * 2. For each candidate type, try to match local specification to this - * candidate target type. Matching involves finding corresponding - * high-level spec accessors, meaning that all named fields should match, - * as well as all array accesses should be within the actual bounds. Also, - * types should be compatible (see bpf_core_fields_are_compat for details). - * 3. It is supported and expected that there might be multiple flavors - * matching the spec. As long as all the specs resolve to the same set of - * offsets across all candidates, there is no error. If there is any - * ambiguity, CO-RE relocation will fail. This is necessary to accomodate - * imprefection of BTF deduplication, which can cause slight duplication of - * the same BTF type, if some directly or indirectly referenced (by - * pointer) type gets resolved to different actual types in different - * object files. If such situation occurs, deduplicated BTF will end up - * with two (or more) structurally identical types, which differ only in - * types they refer to through pointer. This should be OK in most cases and - * is not an error. - * 4. Candidate types search is performed by linearly scanning through all - * types in target BTF. It is anticipated that this is overall more - * efficient memory-wise and not significantly worse (if not better) - * CPU-wise compared to prebuilding a map from all local type names to - * a list of candidate type names. It's also sped up by caching resolved - * list of matching candidates per each local "root" type ID, that has at - * least one bpf_core_relo associated with it. This list is shared - * between multiple relocations for the same type ID and is updated as some - * of the candidates are pruned due to structural incompatibility. - */ static int bpf_core_apply_relo(struct bpf_program *prog, const struct bpf_core_relo *relo, int relo_idx, const struct btf *local_btf, struct hashmap *cand_cache) { - struct bpf_core_spec local_spec, cand_spec, targ_spec = {}; const void *type_key = u32_as_hash_key(relo->type_id); - struct bpf_core_relo_res cand_res, targ_res; + struct bpf_core_cand_list *cands = NULL; + const char *prog_name = prog->name; const struct btf_type *local_type; const char *local_name; - struct core_cand_list *cands = NULL; - __u32 local_id; - const char *spec_str; - int i, j, err; + __u32 local_id = relo->type_id; + struct bpf_insn *insn; + int insn_idx, err; + + if (relo->insn_off % BPF_INSN_SZ) + return -EINVAL; + insn_idx = relo->insn_off / BPF_INSN_SZ; + /* adjust insn_idx from section frame of reference to the local + * program's frame of reference; (sub-)program code is not yet + * relocated, so it's enough to just subtract in-section offset + */ + insn_idx = insn_idx - prog->sec_insn_off; + if (insn_idx > prog->insns_cnt) + return -EINVAL; + insn = &prog->insns[insn_idx]; - local_id = relo->type_id; local_type = btf__type_by_id(local_btf, local_id); if (!local_type) return -EINVAL; @@ -6247,51 +5108,19 @@ static int bpf_core_apply_relo(struct bpf_program *prog, if (!local_name) return -EINVAL; - spec_str = btf__name_by_offset(local_btf, relo->access_str_off); - if (str_is_empty(spec_str)) - return -EINVAL; - if (prog->obj->gen_loader) { - pr_warn("// TODO core_relo: prog %td insn[%d] %s %s kind %d\n", + pr_warn("// TODO core_relo: prog %td insn[%d] %s kind %d\n", prog - prog->obj->programs, relo->insn_off / 8, - local_name, spec_str, relo->kind); + local_name, relo->kind); return -ENOTSUP; } - err = bpf_core_parse_spec(local_btf, local_id, spec_str, relo->kind, &local_spec); - if (err) { - pr_warn("prog '%s': relo #%d: parsing [%d] %s %s + %s failed: %d\n", - prog->name, relo_idx, local_id, btf_kind_str(local_type), - str_is_empty(local_name) ? "<anon>" : local_name, - spec_str, err); - return -EINVAL; - } - - pr_debug("prog '%s': relo #%d: kind <%s> (%d), spec is ", prog->name, - relo_idx, core_relo_kind_str(relo->kind), relo->kind); - bpf_core_dump_spec(LIBBPF_DEBUG, &local_spec); - libbpf_print(LIBBPF_DEBUG, "\n"); - - /* TYPE_ID_LOCAL relo is special and doesn't need candidate search */ - if (relo->kind == BPF_TYPE_ID_LOCAL) { - targ_res.validate = true; - targ_res.poison = false; - targ_res.orig_val = local_spec.root_type_id; - targ_res.new_val = local_spec.root_type_id; - goto patch_insn; - } - /* libbpf doesn't support candidate search for anonymous types */ - if (str_is_empty(spec_str)) { - pr_warn("prog '%s': relo #%d: <%s> (%d) relocation doesn't support anonymous types\n", - prog->name, relo_idx, core_relo_kind_str(relo->kind), relo->kind); - return -EOPNOTSUPP; - } - - if (!hashmap__find(cand_cache, type_key, (void **)&cands)) { + if (relo->kind != BPF_TYPE_ID_LOCAL && + !hashmap__find(cand_cache, type_key, (void **)&cands)) { cands = bpf_core_find_cands(prog->obj, local_btf, local_id); if (IS_ERR(cands)) { pr_warn("prog '%s': relo #%d: target candidate search failed for [%d] %s %s: %ld\n", - prog->name, relo_idx, local_id, btf_kind_str(local_type), + prog_name, relo_idx, local_id, btf_kind_str(local_type), local_name, PTR_ERR(cands)); return PTR_ERR(cands); } @@ -6302,97 +5131,7 @@ static int bpf_core_apply_relo(struct bpf_program *prog, } } - for (i = 0, j = 0; i < cands->len; i++) { - err = bpf_core_spec_match(&local_spec, cands->cands[i].btf, - cands->cands[i].id, &cand_spec); - if (err < 0) { - pr_warn("prog '%s': relo #%d: error matching candidate #%d ", - prog->name, relo_idx, i); - bpf_core_dump_spec(LIBBPF_WARN, &cand_spec); - libbpf_print(LIBBPF_WARN, ": %d\n", err); - return err; - } - - pr_debug("prog '%s': relo #%d: %s candidate #%d ", prog->name, - relo_idx, err == 0 ? "non-matching" : "matching", i); - bpf_core_dump_spec(LIBBPF_DEBUG, &cand_spec); - libbpf_print(LIBBPF_DEBUG, "\n"); - - if (err == 0) - continue; - - err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, &cand_spec, &cand_res); - if (err) - return err; - - if (j == 0) { - targ_res = cand_res; - targ_spec = cand_spec; - } else if (cand_spec.bit_offset != targ_spec.bit_offset) { - /* if there are many field relo candidates, they - * should all resolve to the same bit offset - */ - pr_warn("prog '%s': relo #%d: field offset ambiguity: %u != %u\n", - prog->name, relo_idx, cand_spec.bit_offset, - targ_spec.bit_offset); - return -EINVAL; - } else if (cand_res.poison != targ_res.poison || cand_res.new_val != targ_res.new_val) { - /* all candidates should result in the same relocation - * decision and value, otherwise it's dangerous to - * proceed due to ambiguity - */ - pr_warn("prog '%s': relo #%d: relocation decision ambiguity: %s %u != %s %u\n", - prog->name, relo_idx, - cand_res.poison ? "failure" : "success", cand_res.new_val, - targ_res.poison ? "failure" : "success", targ_res.new_val); - return -EINVAL; - } - - cands->cands[j++] = cands->cands[i]; - } - - /* - * For BPF_FIELD_EXISTS relo or when used BPF program has field - * existence checks or kernel version/config checks, it's expected - * that we might not find any candidates. In this case, if field - * wasn't found in any candidate, the list of candidates shouldn't - * change at all, we'll just handle relocating appropriately, - * depending on relo's kind. - */ - if (j > 0) - cands->len = j; - - /* - * If no candidates were found, it might be both a programmer error, - * as well as expected case, depending whether instruction w/ - * relocation is guarded in some way that makes it unreachable (dead - * code) if relocation can't be resolved. This is handled in - * bpf_core_patch_insn() uniformly by replacing that instruction with - * BPF helper call insn (using invalid helper ID). If that instruction - * is indeed unreachable, then it will be ignored and eliminated by - * verifier. If it was an error, then verifier will complain and point - * to a specific instruction number in its log. - */ - if (j == 0) { - pr_debug("prog '%s': relo #%d: no matching targets found\n", - prog->name, relo_idx); - - /* calculate single target relo result explicitly */ - err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, NULL, &targ_res); - if (err) - return err; - } - -patch_insn: - /* bpf_core_patch_insn() should know how to handle missing targ_spec */ - err = bpf_core_patch_insn(prog, relo, relo_idx, &targ_res); - if (err) { - pr_warn("prog '%s': relo #%d: failed to patch insn #%zu: %d\n", - prog->name, relo_idx, relo->insn_off / BPF_INSN_SZ, err); - return -EINVAL; - } - - return 0; + return bpf_core_apply_relo_insn(prog_name, insn, insn_idx, relo, relo_idx, local_btf, cands); } static int @@ -7232,7 +5971,7 @@ static int bpf_object__collect_relos(struct bpf_object *obj) for (i = 0; i < obj->nr_programs; i++) { struct bpf_program *p = &obj->programs[i]; - + if (!p->nr_reloc) continue; @@ -7596,7 +6335,7 @@ static struct bpf_object * __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, const struct bpf_object_open_opts *opts) { - const char *obj_name, *kconfig; + const char *obj_name, *kconfig, *btf_tmp_path; struct bpf_program *prog; struct bpf_object *obj; char tmp_name[64]; @@ -7627,11 +6366,26 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, if (IS_ERR(obj)) return obj; + btf_tmp_path = OPTS_GET(opts, btf_custom_path, NULL); + if (btf_tmp_path) { + if (strlen(btf_tmp_path) >= PATH_MAX) { + err = -ENAMETOOLONG; + goto out; + } + obj->btf_custom_path = strdup(btf_tmp_path); + if (!obj->btf_custom_path) { + err = -ENOMEM; + goto out; + } + } + kconfig = OPTS_GET(opts, kconfig, NULL); if (kconfig) { obj->kconfig = strdup(kconfig); - if (!obj->kconfig) - return ERR_PTR(-ENOMEM); + if (!obj->kconfig) { + err = -ENOMEM; + goto out; + } } err = bpf_object__elf_init(obj); @@ -8097,7 +6851,7 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr) err = err ? : bpf_object__sanitize_maps(obj); err = err ? : bpf_object__init_kern_struct_ops_maps(obj); err = err ? : bpf_object__create_maps(obj); - err = err ? : bpf_object__relocate(obj, attr->target_btf_path); + err = err ? : bpf_object__relocate(obj, obj->btf_custom_path ? : attr->target_btf_path); err = err ? : bpf_object__load_progs(obj, attr->log_level); if (obj->gen_loader) { @@ -8492,6 +7246,11 @@ const char *bpf_map__get_pin_path(const struct bpf_map *map) return map->pin_path; } +const char *bpf_map__pin_path(const struct bpf_map *map) +{ + return map->pin_path; +} + bool bpf_map__is_pinned(const struct bpf_map *map) { return map->pinned; @@ -8744,6 +7503,7 @@ void bpf_object__close(struct bpf_object *obj) for (i = 0; i < obj->nr_maps; i++) bpf_map__destroy(&obj->maps[i]); + zfree(&obj->btf_custom_path); zfree(&obj->kconfig); zfree(&obj->externs); obj->nr_extern = 0; @@ -9513,7 +8273,7 @@ static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, ret = snprintf(btf_type_name, sizeof(btf_type_name), "%s%s", prefix, name); /* snprintf returns the number of characters written excluding the - * the terminating null. So, if >= BTF_MAX_NAME_SIZE are written, it + * terminating null. So, if >= BTF_MAX_NAME_SIZE are written, it * indicates truncation. */ if (ret < 0 || ret >= sizeof(btf_type_name)) @@ -9537,7 +8297,7 @@ int libbpf_find_vmlinux_btf_id(const char *name, struct btf *btf; int err; - btf = libbpf_find_kernel_btf(); + btf = btf__load_vmlinux_btf(); err = libbpf_get_error(btf); if (err) { pr_warn("vmlinux BTF is not found\n"); @@ -9556,8 +8316,8 @@ static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) { struct bpf_prog_info_linear *info_linear; struct bpf_prog_info *info; - struct btf *btf = NULL; - int err = -EINVAL; + struct btf *btf; + int err; info_linear = bpf_program__get_prog_info_linear(attach_prog_fd, 0); err = libbpf_get_error(info_linear); @@ -9566,12 +8326,15 @@ static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) attach_prog_fd); return err; } + + err = -EINVAL; info = &info_linear->info; if (!info->btf_id) { pr_warn("The target program doesn't have BTF\n"); goto out; } - if (btf__get_from_id(info->btf_id, &btf)) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { pr_warn("Failed to get BTF of the program\n"); goto out; } @@ -10055,7 +8818,7 @@ struct bpf_link { int bpf_link__update_program(struct bpf_link *link, struct bpf_program *prog) { int ret; - + ret = bpf_link_update(bpf_link__fd(link), bpf_program__fd(prog), NULL); return libbpf_err_errno(ret); } @@ -10346,25 +9109,28 @@ static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, return pfd; } -struct bpf_program_attach_kprobe_opts { - bool retprobe; - unsigned long offset; -}; - -static struct bpf_link* +struct bpf_link * bpf_program__attach_kprobe_opts(struct bpf_program *prog, const char *func_name, - struct bpf_program_attach_kprobe_opts *opts) + struct bpf_kprobe_opts *opts) { char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; + unsigned long offset; + bool retprobe; int pfd, err; - pfd = perf_event_open_probe(false /* uprobe */, opts->retprobe, func_name, - opts->offset, -1 /* pid */); + if (!OPTS_VALID(opts, bpf_kprobe_opts)) + return libbpf_err_ptr(-EINVAL); + + retprobe = OPTS_GET(opts, retprobe, false); + offset = OPTS_GET(opts, offset, 0); + + pfd = perf_event_open_probe(false /* uprobe */, retprobe, func_name, + offset, -1 /* pid */); if (pfd < 0) { pr_warn("prog '%s': failed to create %s '%s' perf event: %s\n", - prog->name, opts->retprobe ? "kretprobe" : "kprobe", func_name, + prog->name, retprobe ? "kretprobe" : "kprobe", func_name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); return libbpf_err_ptr(pfd); } @@ -10373,7 +9139,7 @@ bpf_program__attach_kprobe_opts(struct bpf_program *prog, if (err) { close(pfd); pr_warn("prog '%s': failed to attach to %s '%s': %s\n", - prog->name, opts->retprobe ? "kretprobe" : "kprobe", func_name, + prog->name, retprobe ? "kretprobe" : "kprobe", func_name, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); return libbpf_err_ptr(err); } @@ -10384,9 +9150,9 @@ struct bpf_link *bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe, const char *func_name) { - struct bpf_program_attach_kprobe_opts opts = { + DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts, .retprobe = retprobe, - }; + ); return bpf_program__attach_kprobe_opts(prog, func_name, &opts); } @@ -10394,7 +9160,7 @@ struct bpf_link *bpf_program__attach_kprobe(struct bpf_program *prog, static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, struct bpf_program *prog) { - struct bpf_program_attach_kprobe_opts opts; + DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts); unsigned long offset = 0; struct bpf_link *link; const char *func_name; @@ -10404,13 +9170,14 @@ static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, func_name = prog->sec_name + sec->len; opts.retprobe = strcmp(sec->sec, "kretprobe/") == 0; - n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%lx", &func, &offset); + n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset); if (n < 1) { err = -EINVAL; pr_warn("kprobe name is invalid: %s\n", func_name); return libbpf_err_ptr(err); } if (opts.retprobe && offset != 0) { + free(func); err = -EINVAL; pr_warn("kretprobes do not support offset specification\n"); return libbpf_err_ptr(err); diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 6e61342ba56c..1271d99bb7aa 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -94,8 +94,26 @@ struct bpf_object_open_opts { * system Kconfig for CONFIG_xxx externs. */ const char *kconfig; + /* Path to the custom BTF to be used for BPF CO-RE relocations. + * This custom BTF completely replaces the use of vmlinux BTF + * for the purpose of CO-RE relocations. + * NOTE: any other BPF feature (e.g., fentry/fexit programs, + * struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux. + */ + const char *btf_custom_path; }; -#define bpf_object_open_opts__last_field kconfig +#define bpf_object_open_opts__last_field btf_custom_path + +struct bpf_kprobe_opts { + /* size of this struct, for forward/backward compatiblity */ + size_t sz; + /* function's offset to install kprobe to */ + unsigned long offset; + /* kprobe is return probe */ + bool retprobe; + size_t :0; +}; +#define bpf_kprobe_opts__last_field retprobe LIBBPF_API struct bpf_object *bpf_object__open(const char *path); LIBBPF_API struct bpf_object * @@ -243,6 +261,10 @@ LIBBPF_API struct bpf_link * bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe, const char *func_name); LIBBPF_API struct bpf_link * +bpf_program__attach_kprobe_opts(struct bpf_program *prog, + const char *func_name, + struct bpf_kprobe_opts *opts); +LIBBPF_API struct bpf_link * bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe, pid_t pid, const char *binary_path, size_t func_offset); @@ -477,6 +499,7 @@ LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map); LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map); LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path); LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map); +LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map); LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map); LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path); LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path); diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 944c99d1ded3..58e0fb2c482f 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -371,7 +371,15 @@ LIBBPF_0.4.0 { LIBBPF_0.5.0 { global: bpf_map__initial_value; + bpf_map__pin_path; bpf_map_lookup_and_delete_elem_flags; + bpf_program__attach_kprobe_opts; bpf_object__gen_loader; + btf__load_from_kernel_by_id; + btf__load_from_kernel_by_id_split; + btf__load_into_kernel; + btf__load_module_btf; + btf__load_vmlinux_btf; + btf_dump__dump_type_data; libbpf_set_strict_mode; } LIBBPF_0.4.0; diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 016ca7cb4f8a..f7b691d5f9eb 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -14,6 +14,7 @@ #include <errno.h> #include <linux/err.h> #include "libbpf_legacy.h" +#include "relo_core.h" /* make sure libbpf doesn't use kernel-only integer typedefs */ #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64 @@ -366,76 +367,6 @@ struct bpf_line_info_min { __u32 line_col; }; -/* bpf_core_relo_kind encodes which aspect of captured field/type/enum value - * has to be adjusted by relocations. - */ -enum bpf_core_relo_kind { - BPF_FIELD_BYTE_OFFSET = 0, /* field byte offset */ - BPF_FIELD_BYTE_SIZE = 1, /* field size in bytes */ - BPF_FIELD_EXISTS = 2, /* field existence in target kernel */ - BPF_FIELD_SIGNED = 3, /* field signedness (0 - unsigned, 1 - signed) */ - BPF_FIELD_LSHIFT_U64 = 4, /* bitfield-specific left bitshift */ - BPF_FIELD_RSHIFT_U64 = 5, /* bitfield-specific right bitshift */ - BPF_TYPE_ID_LOCAL = 6, /* type ID in local BPF object */ - BPF_TYPE_ID_TARGET = 7, /* type ID in target kernel */ - BPF_TYPE_EXISTS = 8, /* type existence in target kernel */ - BPF_TYPE_SIZE = 9, /* type size in bytes */ - BPF_ENUMVAL_EXISTS = 10, /* enum value existence in target kernel */ - BPF_ENUMVAL_VALUE = 11, /* enum value integer value */ -}; - -/* The minimum bpf_core_relo checked by the loader - * - * CO-RE relocation captures the following data: - * - insn_off - instruction offset (in bytes) within a BPF program that needs - * its insn->imm field to be relocated with actual field info; - * - type_id - BTF type ID of the "root" (containing) entity of a relocatable - * type or field; - * - access_str_off - offset into corresponding .BTF string section. String - * interpretation depends on specific relocation kind: - * - for field-based relocations, string encodes an accessed field using - * a sequence of field and array indices, separated by colon (:). It's - * conceptually very close to LLVM's getelementptr ([0]) instruction's - * arguments for identifying offset to a field. - * - for type-based relocations, strings is expected to be just "0"; - * - for enum value-based relocations, string contains an index of enum - * value within its enum type; - * - * Example to provide a better feel. - * - * struct sample { - * int a; - * struct { - * int b[10]; - * }; - * }; - * - * struct sample *s = ...; - * int x = &s->a; // encoded as "0:0" (a is field #0) - * int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1, - * // b is field #0 inside anon struct, accessing elem #5) - * int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array) - * - * type_id for all relocs in this example will capture BTF type id of - * `struct sample`. - * - * Such relocation is emitted when using __builtin_preserve_access_index() - * Clang built-in, passing expression that captures field address, e.g.: - * - * bpf_probe_read(&dst, sizeof(dst), - * __builtin_preserve_access_index(&src->a.b.c)); - * - * In this case Clang will emit field relocation recording necessary data to - * be able to find offset of embedded `a.b.c` field within `src` struct. - * - * [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction - */ -struct bpf_core_relo { - __u32 insn_off; - __u32 type_id; - __u32 access_str_off; - enum bpf_core_relo_kind kind; -}; typedef int (*type_id_visit_fn)(__u32 *type_id, void *ctx); typedef int (*str_off_visit_fn)(__u32 *str_off, void *ctx); @@ -494,4 +425,14 @@ static inline void *libbpf_ptr(void *ret) return ret; } +static inline bool str_is_empty(const char *s) +{ + return !s || !s[0]; +} + +static inline bool is_ldimm64_insn(struct bpf_insn *insn) +{ + return insn->code == (BPF_LD | BPF_IMM | BPF_DW); +} + #endif /* __LIBBPF_LIBBPF_INTERNAL_H */ diff --git a/tools/lib/bpf/relo_core.c b/tools/lib/bpf/relo_core.c new file mode 100644 index 000000000000..4016ed492d0c --- /dev/null +++ b/tools/lib/bpf/relo_core.c @@ -0,0 +1,1295 @@ +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) +/* Copyright (c) 2019 Facebook */ + +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <ctype.h> +#include <linux/err.h> + +#include "libbpf.h" +#include "bpf.h" +#include "btf.h" +#include "str_error.h" +#include "libbpf_internal.h" + +#define BPF_CORE_SPEC_MAX_LEN 64 + +/* represents BPF CO-RE field or array element accessor */ +struct bpf_core_accessor { + __u32 type_id; /* struct/union type or array element type */ + __u32 idx; /* field index or array index */ + const char *name; /* field name or NULL for array accessor */ +}; + +struct bpf_core_spec { + const struct btf *btf; + /* high-level spec: named fields and array indices only */ + struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN]; + /* original unresolved (no skip_mods_or_typedefs) root type ID */ + __u32 root_type_id; + /* CO-RE relocation kind */ + enum bpf_core_relo_kind relo_kind; + /* high-level spec length */ + int len; + /* raw, low-level spec: 1-to-1 with accessor spec string */ + int raw_spec[BPF_CORE_SPEC_MAX_LEN]; + /* raw spec length */ + int raw_len; + /* field bit offset represented by spec */ + __u32 bit_offset; +}; + +static bool is_flex_arr(const struct btf *btf, + const struct bpf_core_accessor *acc, + const struct btf_array *arr) +{ + const struct btf_type *t; + + /* not a flexible array, if not inside a struct or has non-zero size */ + if (!acc->name || arr->nelems > 0) + return false; + + /* has to be the last member of enclosing struct */ + t = btf__type_by_id(btf, acc->type_id); + return acc->idx == btf_vlen(t) - 1; +} + +static const char *core_relo_kind_str(enum bpf_core_relo_kind kind) +{ + switch (kind) { + case BPF_FIELD_BYTE_OFFSET: return "byte_off"; + case BPF_FIELD_BYTE_SIZE: return "byte_sz"; + case BPF_FIELD_EXISTS: return "field_exists"; + case BPF_FIELD_SIGNED: return "signed"; + case BPF_FIELD_LSHIFT_U64: return "lshift_u64"; + case BPF_FIELD_RSHIFT_U64: return "rshift_u64"; + case BPF_TYPE_ID_LOCAL: return "local_type_id"; + case BPF_TYPE_ID_TARGET: return "target_type_id"; + case BPF_TYPE_EXISTS: return "type_exists"; + case BPF_TYPE_SIZE: return "type_size"; + case BPF_ENUMVAL_EXISTS: return "enumval_exists"; + case BPF_ENUMVAL_VALUE: return "enumval_value"; + default: return "unknown"; + } +} + +static bool core_relo_is_field_based(enum bpf_core_relo_kind kind) +{ + switch (kind) { + case BPF_FIELD_BYTE_OFFSET: + case BPF_FIELD_BYTE_SIZE: + case BPF_FIELD_EXISTS: + case BPF_FIELD_SIGNED: + case BPF_FIELD_LSHIFT_U64: + case BPF_FIELD_RSHIFT_U64: + return true; + default: + return false; + } +} + +static bool core_relo_is_type_based(enum bpf_core_relo_kind kind) +{ + switch (kind) { + case BPF_TYPE_ID_LOCAL: + case BPF_TYPE_ID_TARGET: + case BPF_TYPE_EXISTS: + case BPF_TYPE_SIZE: + return true; + default: + return false; + } +} + +static bool core_relo_is_enumval_based(enum bpf_core_relo_kind kind) +{ + switch (kind) { + case BPF_ENUMVAL_EXISTS: + case BPF_ENUMVAL_VALUE: + return true; + default: + return false; + } +} + +/* + * Turn bpf_core_relo into a low- and high-level spec representation, + * validating correctness along the way, as well as calculating resulting + * field bit offset, specified by accessor string. Low-level spec captures + * every single level of nestedness, including traversing anonymous + * struct/union members. High-level one only captures semantically meaningful + * "turning points": named fields and array indicies. + * E.g., for this case: + * + * struct sample { + * int __unimportant; + * struct { + * int __1; + * int __2; + * int a[7]; + * }; + * }; + * + * struct sample *s = ...; + * + * int x = &s->a[3]; // access string = '0:1:2:3' + * + * Low-level spec has 1:1 mapping with each element of access string (it's + * just a parsed access string representation): [0, 1, 2, 3]. + * + * High-level spec will capture only 3 points: + * - intial zero-index access by pointer (&s->... is the same as &s[0]...); + * - field 'a' access (corresponds to '2' in low-level spec); + * - array element #3 access (corresponds to '3' in low-level spec). + * + * Type-based relocations (TYPE_EXISTS/TYPE_SIZE, + * TYPE_ID_LOCAL/TYPE_ID_TARGET) don't capture any field information. Their + * spec and raw_spec are kept empty. + * + * Enum value-based relocations (ENUMVAL_EXISTS/ENUMVAL_VALUE) use access + * string to specify enumerator's value index that need to be relocated. + */ +static int bpf_core_parse_spec(const struct btf *btf, + __u32 type_id, + const char *spec_str, + enum bpf_core_relo_kind relo_kind, + struct bpf_core_spec *spec) +{ + int access_idx, parsed_len, i; + struct bpf_core_accessor *acc; + const struct btf_type *t; + const char *name; + __u32 id; + __s64 sz; + + if (str_is_empty(spec_str) || *spec_str == ':') + return -EINVAL; + + memset(spec, 0, sizeof(*spec)); + spec->btf = btf; + spec->root_type_id = type_id; + spec->relo_kind = relo_kind; + + /* type-based relocations don't have a field access string */ + if (core_relo_is_type_based(relo_kind)) { + if (strcmp(spec_str, "0")) + return -EINVAL; + return 0; + } + + /* parse spec_str="0:1:2:3:4" into array raw_spec=[0, 1, 2, 3, 4] */ + while (*spec_str) { + if (*spec_str == ':') + ++spec_str; + if (sscanf(spec_str, "%d%n", &access_idx, &parsed_len) != 1) + return -EINVAL; + if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) + return -E2BIG; + spec_str += parsed_len; + spec->raw_spec[spec->raw_len++] = access_idx; + } + + if (spec->raw_len == 0) + return -EINVAL; + + t = skip_mods_and_typedefs(btf, type_id, &id); + if (!t) + return -EINVAL; + + access_idx = spec->raw_spec[0]; + acc = &spec->spec[0]; + acc->type_id = id; + acc->idx = access_idx; + spec->len++; + + if (core_relo_is_enumval_based(relo_kind)) { + if (!btf_is_enum(t) || spec->raw_len > 1 || access_idx >= btf_vlen(t)) + return -EINVAL; + + /* record enumerator name in a first accessor */ + acc->name = btf__name_by_offset(btf, btf_enum(t)[access_idx].name_off); + return 0; + } + + if (!core_relo_is_field_based(relo_kind)) + return -EINVAL; + + sz = btf__resolve_size(btf, id); + if (sz < 0) + return sz; + spec->bit_offset = access_idx * sz * 8; + + for (i = 1; i < spec->raw_len; i++) { + t = skip_mods_and_typedefs(btf, id, &id); + if (!t) + return -EINVAL; + + access_idx = spec->raw_spec[i]; + acc = &spec->spec[spec->len]; + + if (btf_is_composite(t)) { + const struct btf_member *m; + __u32 bit_offset; + + if (access_idx >= btf_vlen(t)) + return -EINVAL; + + bit_offset = btf_member_bit_offset(t, access_idx); + spec->bit_offset += bit_offset; + + m = btf_members(t) + access_idx; + if (m->name_off) { + name = btf__name_by_offset(btf, m->name_off); + if (str_is_empty(name)) + return -EINVAL; + + acc->type_id = id; + acc->idx = access_idx; + acc->name = name; + spec->len++; + } + + id = m->type; + } else if (btf_is_array(t)) { + const struct btf_array *a = btf_array(t); + bool flex; + + t = skip_mods_and_typedefs(btf, a->type, &id); + if (!t) + return -EINVAL; + + flex = is_flex_arr(btf, acc - 1, a); + if (!flex && access_idx >= a->nelems) + return -EINVAL; + + spec->spec[spec->len].type_id = id; + spec->spec[spec->len].idx = access_idx; + spec->len++; + + sz = btf__resolve_size(btf, id); + if (sz < 0) + return sz; + spec->bit_offset += access_idx * sz * 8; + } else { + pr_warn("relo for [%u] %s (at idx %d) captures type [%d] of unexpected kind %s\n", + type_id, spec_str, i, id, btf_kind_str(t)); + return -EINVAL; + } + } + + return 0; +} + +/* Check two types for compatibility for the purpose of field access + * relocation. const/volatile/restrict and typedefs are skipped to ensure we + * are relocating semantically compatible entities: + * - any two STRUCTs/UNIONs are compatible and can be mixed; + * - any two FWDs are compatible, if their names match (modulo flavor suffix); + * - any two PTRs are always compatible; + * - for ENUMs, names should be the same (ignoring flavor suffix) or at + * least one of enums should be anonymous; + * - for ENUMs, check sizes, names are ignored; + * - for INT, size and signedness are ignored; + * - any two FLOATs are always compatible; + * - for ARRAY, dimensionality is ignored, element types are checked for + * compatibility recursively; + * - everything else shouldn't be ever a target of relocation. + * These rules are not set in stone and probably will be adjusted as we get + * more experience with using BPF CO-RE relocations. + */ +static int bpf_core_fields_are_compat(const struct btf *local_btf, + __u32 local_id, + const struct btf *targ_btf, + __u32 targ_id) +{ + const struct btf_type *local_type, *targ_type; + +recur: + local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); + targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); + if (!local_type || !targ_type) + return -EINVAL; + + if (btf_is_composite(local_type) && btf_is_composite(targ_type)) + return 1; + if (btf_kind(local_type) != btf_kind(targ_type)) + return 0; + + switch (btf_kind(local_type)) { + case BTF_KIND_PTR: + case BTF_KIND_FLOAT: + return 1; + case BTF_KIND_FWD: + case BTF_KIND_ENUM: { + const char *local_name, *targ_name; + size_t local_len, targ_len; + + local_name = btf__name_by_offset(local_btf, + local_type->name_off); + targ_name = btf__name_by_offset(targ_btf, targ_type->name_off); + local_len = bpf_core_essential_name_len(local_name); + targ_len = bpf_core_essential_name_len(targ_name); + /* one of them is anonymous or both w/ same flavor-less names */ + return local_len == 0 || targ_len == 0 || + (local_len == targ_len && + strncmp(local_name, targ_name, local_len) == 0); + } + case BTF_KIND_INT: + /* just reject deprecated bitfield-like integers; all other + * integers are by default compatible between each other + */ + return btf_int_offset(local_type) == 0 && + btf_int_offset(targ_type) == 0; + case BTF_KIND_ARRAY: + local_id = btf_array(local_type)->type; + targ_id = btf_array(targ_type)->type; + goto recur; + default: + pr_warn("unexpected kind %d relocated, local [%d], target [%d]\n", + btf_kind(local_type), local_id, targ_id); + return 0; + } +} + +/* + * Given single high-level named field accessor in local type, find + * corresponding high-level accessor for a target type. Along the way, + * maintain low-level spec for target as well. Also keep updating target + * bit offset. + * + * Searching is performed through recursive exhaustive enumeration of all + * fields of a struct/union. If there are any anonymous (embedded) + * structs/unions, they are recursively searched as well. If field with + * desired name is found, check compatibility between local and target types, + * before returning result. + * + * 1 is returned, if field is found. + * 0 is returned if no compatible field is found. + * <0 is returned on error. + */ +static int bpf_core_match_member(const struct btf *local_btf, + const struct bpf_core_accessor *local_acc, + const struct btf *targ_btf, + __u32 targ_id, + struct bpf_core_spec *spec, + __u32 *next_targ_id) +{ + const struct btf_type *local_type, *targ_type; + const struct btf_member *local_member, *m; + const char *local_name, *targ_name; + __u32 local_id; + int i, n, found; + + targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); + if (!targ_type) + return -EINVAL; + if (!btf_is_composite(targ_type)) + return 0; + + local_id = local_acc->type_id; + local_type = btf__type_by_id(local_btf, local_id); + local_member = btf_members(local_type) + local_acc->idx; + local_name = btf__name_by_offset(local_btf, local_member->name_off); + + n = btf_vlen(targ_type); + m = btf_members(targ_type); + for (i = 0; i < n; i++, m++) { + __u32 bit_offset; + + bit_offset = btf_member_bit_offset(targ_type, i); + + /* too deep struct/union/array nesting */ + if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) + return -E2BIG; + + /* speculate this member will be the good one */ + spec->bit_offset += bit_offset; + spec->raw_spec[spec->raw_len++] = i; + + targ_name = btf__name_by_offset(targ_btf, m->name_off); + if (str_is_empty(targ_name)) { + /* embedded struct/union, we need to go deeper */ + found = bpf_core_match_member(local_btf, local_acc, + targ_btf, m->type, + spec, next_targ_id); + if (found) /* either found or error */ + return found; + } else if (strcmp(local_name, targ_name) == 0) { + /* matching named field */ + struct bpf_core_accessor *targ_acc; + + targ_acc = &spec->spec[spec->len++]; + targ_acc->type_id = targ_id; + targ_acc->idx = i; + targ_acc->name = targ_name; + + *next_targ_id = m->type; + found = bpf_core_fields_are_compat(local_btf, + local_member->type, + targ_btf, m->type); + if (!found) + spec->len--; /* pop accessor */ + return found; + } + /* member turned out not to be what we looked for */ + spec->bit_offset -= bit_offset; + spec->raw_len--; + } + + return 0; +} + +/* + * Try to match local spec to a target type and, if successful, produce full + * target spec (high-level, low-level + bit offset). + */ +static int bpf_core_spec_match(struct bpf_core_spec *local_spec, + const struct btf *targ_btf, __u32 targ_id, + struct bpf_core_spec *targ_spec) +{ + const struct btf_type *targ_type; + const struct bpf_core_accessor *local_acc; + struct bpf_core_accessor *targ_acc; + int i, sz, matched; + + memset(targ_spec, 0, sizeof(*targ_spec)); + targ_spec->btf = targ_btf; + targ_spec->root_type_id = targ_id; + targ_spec->relo_kind = local_spec->relo_kind; + + if (core_relo_is_type_based(local_spec->relo_kind)) { + return bpf_core_types_are_compat(local_spec->btf, + local_spec->root_type_id, + targ_btf, targ_id); + } + + local_acc = &local_spec->spec[0]; + targ_acc = &targ_spec->spec[0]; + + if (core_relo_is_enumval_based(local_spec->relo_kind)) { + size_t local_essent_len, targ_essent_len; + const struct btf_enum *e; + const char *targ_name; + + /* has to resolve to an enum */ + targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, &targ_id); + if (!btf_is_enum(targ_type)) + return 0; + + local_essent_len = bpf_core_essential_name_len(local_acc->name); + + for (i = 0, e = btf_enum(targ_type); i < btf_vlen(targ_type); i++, e++) { + targ_name = btf__name_by_offset(targ_spec->btf, e->name_off); + targ_essent_len = bpf_core_essential_name_len(targ_name); + if (targ_essent_len != local_essent_len) + continue; + if (strncmp(local_acc->name, targ_name, local_essent_len) == 0) { + targ_acc->type_id = targ_id; + targ_acc->idx = i; + targ_acc->name = targ_name; + targ_spec->len++; + targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; + targ_spec->raw_len++; + return 1; + } + } + return 0; + } + + if (!core_relo_is_field_based(local_spec->relo_kind)) + return -EINVAL; + + for (i = 0; i < local_spec->len; i++, local_acc++, targ_acc++) { + targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, + &targ_id); + if (!targ_type) + return -EINVAL; + + if (local_acc->name) { + matched = bpf_core_match_member(local_spec->btf, + local_acc, + targ_btf, targ_id, + targ_spec, &targ_id); + if (matched <= 0) + return matched; + } else { + /* for i=0, targ_id is already treated as array element + * type (because it's the original struct), for others + * we should find array element type first + */ + if (i > 0) { + const struct btf_array *a; + bool flex; + + if (!btf_is_array(targ_type)) + return 0; + + a = btf_array(targ_type); + flex = is_flex_arr(targ_btf, targ_acc - 1, a); + if (!flex && local_acc->idx >= a->nelems) + return 0; + if (!skip_mods_and_typedefs(targ_btf, a->type, + &targ_id)) + return -EINVAL; + } + + /* too deep struct/union/array nesting */ + if (targ_spec->raw_len == BPF_CORE_SPEC_MAX_LEN) + return -E2BIG; + + targ_acc->type_id = targ_id; + targ_acc->idx = local_acc->idx; + targ_acc->name = NULL; + targ_spec->len++; + targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; + targ_spec->raw_len++; + + sz = btf__resolve_size(targ_btf, targ_id); + if (sz < 0) + return sz; + targ_spec->bit_offset += local_acc->idx * sz * 8; + } + } + + return 1; +} + +static int bpf_core_calc_field_relo(const char *prog_name, + const struct bpf_core_relo *relo, + const struct bpf_core_spec *spec, + __u32 *val, __u32 *field_sz, __u32 *type_id, + bool *validate) +{ + const struct bpf_core_accessor *acc; + const struct btf_type *t; + __u32 byte_off, byte_sz, bit_off, bit_sz, field_type_id; + const struct btf_member *m; + const struct btf_type *mt; + bool bitfield; + __s64 sz; + + *field_sz = 0; + + if (relo->kind == BPF_FIELD_EXISTS) { + *val = spec ? 1 : 0; + return 0; + } + + if (!spec) + return -EUCLEAN; /* request instruction poisoning */ + + acc = &spec->spec[spec->len - 1]; + t = btf__type_by_id(spec->btf, acc->type_id); + + /* a[n] accessor needs special handling */ + if (!acc->name) { + if (relo->kind == BPF_FIELD_BYTE_OFFSET) { + *val = spec->bit_offset / 8; + /* remember field size for load/store mem size */ + sz = btf__resolve_size(spec->btf, acc->type_id); + if (sz < 0) + return -EINVAL; + *field_sz = sz; + *type_id = acc->type_id; + } else if (relo->kind == BPF_FIELD_BYTE_SIZE) { + sz = btf__resolve_size(spec->btf, acc->type_id); + if (sz < 0) + return -EINVAL; + *val = sz; + } else { + pr_warn("prog '%s': relo %d at insn #%d can't be applied to array access\n", + prog_name, relo->kind, relo->insn_off / 8); + return -EINVAL; + } + if (validate) + *validate = true; + return 0; + } + + m = btf_members(t) + acc->idx; + mt = skip_mods_and_typedefs(spec->btf, m->type, &field_type_id); + bit_off = spec->bit_offset; + bit_sz = btf_member_bitfield_size(t, acc->idx); + + bitfield = bit_sz > 0; + if (bitfield) { + byte_sz = mt->size; + byte_off = bit_off / 8 / byte_sz * byte_sz; + /* figure out smallest int size necessary for bitfield load */ + while (bit_off + bit_sz - byte_off * 8 > byte_sz * 8) { + if (byte_sz >= 8) { + /* bitfield can't be read with 64-bit read */ + pr_warn("prog '%s': relo %d at insn #%d can't be satisfied for bitfield\n", + prog_name, relo->kind, relo->insn_off / 8); + return -E2BIG; + } + byte_sz *= 2; + byte_off = bit_off / 8 / byte_sz * byte_sz; + } + } else { + sz = btf__resolve_size(spec->btf, field_type_id); + if (sz < 0) + return -EINVAL; + byte_sz = sz; + byte_off = spec->bit_offset / 8; + bit_sz = byte_sz * 8; + } + + /* for bitfields, all the relocatable aspects are ambiguous and we + * might disagree with compiler, so turn off validation of expected + * value, except for signedness + */ + if (validate) + *validate = !bitfield; + + switch (relo->kind) { + case BPF_FIELD_BYTE_OFFSET: + *val = byte_off; + if (!bitfield) { + *field_sz = byte_sz; + *type_id = field_type_id; + } + break; + case BPF_FIELD_BYTE_SIZE: + *val = byte_sz; + break; + case BPF_FIELD_SIGNED: + /* enums will be assumed unsigned */ + *val = btf_is_enum(mt) || + (btf_int_encoding(mt) & BTF_INT_SIGNED); + if (validate) + *validate = true; /* signedness is never ambiguous */ + break; + case BPF_FIELD_LSHIFT_U64: +#if __BYTE_ORDER == __LITTLE_ENDIAN + *val = 64 - (bit_off + bit_sz - byte_off * 8); +#else + *val = (8 - byte_sz) * 8 + (bit_off - byte_off * 8); +#endif + break; + case BPF_FIELD_RSHIFT_U64: + *val = 64 - bit_sz; + if (validate) + *validate = true; /* right shift is never ambiguous */ + break; + case BPF_FIELD_EXISTS: + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int bpf_core_calc_type_relo(const struct bpf_core_relo *relo, + const struct bpf_core_spec *spec, + __u32 *val) +{ + __s64 sz; + + /* type-based relos return zero when target type is not found */ + if (!spec) { + *val = 0; + return 0; + } + + switch (relo->kind) { + case BPF_TYPE_ID_TARGET: + *val = spec->root_type_id; + break; + case BPF_TYPE_EXISTS: + *val = 1; + break; + case BPF_TYPE_SIZE: + sz = btf__resolve_size(spec->btf, spec->root_type_id); + if (sz < 0) + return -EINVAL; + *val = sz; + break; + case BPF_TYPE_ID_LOCAL: + /* BPF_TYPE_ID_LOCAL is handled specially and shouldn't get here */ + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo, + const struct bpf_core_spec *spec, + __u32 *val) +{ + const struct btf_type *t; + const struct btf_enum *e; + + switch (relo->kind) { + case BPF_ENUMVAL_EXISTS: + *val = spec ? 1 : 0; + break; + case BPF_ENUMVAL_VALUE: + if (!spec) + return -EUCLEAN; /* request instruction poisoning */ + t = btf__type_by_id(spec->btf, spec->spec[0].type_id); + e = btf_enum(t) + spec->spec[0].idx; + *val = e->val; + break; + default: + return -EOPNOTSUPP; + } + + return 0; +} + +struct bpf_core_relo_res +{ + /* expected value in the instruction, unless validate == false */ + __u32 orig_val; + /* new value that needs to be patched up to */ + __u32 new_val; + /* relocation unsuccessful, poison instruction, but don't fail load */ + bool poison; + /* some relocations can't be validated against orig_val */ + bool validate; + /* for field byte offset relocations or the forms: + * *(T *)(rX + <off>) = rY + * rX = *(T *)(rY + <off>), + * we remember original and resolved field size to adjust direct + * memory loads of pointers and integers; this is necessary for 32-bit + * host kernel architectures, but also allows to automatically + * relocate fields that were resized from, e.g., u32 to u64, etc. + */ + bool fail_memsz_adjust; + __u32 orig_sz; + __u32 orig_type_id; + __u32 new_sz; + __u32 new_type_id; +}; + +/* Calculate original and target relocation values, given local and target + * specs and relocation kind. These values are calculated for each candidate. + * If there are multiple candidates, resulting values should all be consistent + * with each other. Otherwise, libbpf will refuse to proceed due to ambiguity. + * If instruction has to be poisoned, *poison will be set to true. + */ +static int bpf_core_calc_relo(const char *prog_name, + const struct bpf_core_relo *relo, + int relo_idx, + const struct bpf_core_spec *local_spec, + const struct bpf_core_spec *targ_spec, + struct bpf_core_relo_res *res) +{ + int err = -EOPNOTSUPP; + + res->orig_val = 0; + res->new_val = 0; + res->poison = false; + res->validate = true; + res->fail_memsz_adjust = false; + res->orig_sz = res->new_sz = 0; + res->orig_type_id = res->new_type_id = 0; + + if (core_relo_is_field_based(relo->kind)) { + err = bpf_core_calc_field_relo(prog_name, relo, local_spec, + &res->orig_val, &res->orig_sz, + &res->orig_type_id, &res->validate); + err = err ?: bpf_core_calc_field_relo(prog_name, relo, targ_spec, + &res->new_val, &res->new_sz, + &res->new_type_id, NULL); + if (err) + goto done; + /* Validate if it's safe to adjust load/store memory size. + * Adjustments are performed only if original and new memory + * sizes differ. + */ + res->fail_memsz_adjust = false; + if (res->orig_sz != res->new_sz) { + const struct btf_type *orig_t, *new_t; + + orig_t = btf__type_by_id(local_spec->btf, res->orig_type_id); + new_t = btf__type_by_id(targ_spec->btf, res->new_type_id); + + /* There are two use cases in which it's safe to + * adjust load/store's mem size: + * - reading a 32-bit kernel pointer, while on BPF + * size pointers are always 64-bit; in this case + * it's safe to "downsize" instruction size due to + * pointer being treated as unsigned integer with + * zero-extended upper 32-bits; + * - reading unsigned integers, again due to + * zero-extension is preserving the value correctly. + * + * In all other cases it's incorrect to attempt to + * load/store field because read value will be + * incorrect, so we poison relocated instruction. + */ + if (btf_is_ptr(orig_t) && btf_is_ptr(new_t)) + goto done; + if (btf_is_int(orig_t) && btf_is_int(new_t) && + btf_int_encoding(orig_t) != BTF_INT_SIGNED && + btf_int_encoding(new_t) != BTF_INT_SIGNED) + goto done; + + /* mark as invalid mem size adjustment, but this will + * only be checked for LDX/STX/ST insns + */ + res->fail_memsz_adjust = true; + } + } else if (core_relo_is_type_based(relo->kind)) { + err = bpf_core_calc_type_relo(relo, local_spec, &res->orig_val); + err = err ?: bpf_core_calc_type_relo(relo, targ_spec, &res->new_val); + } else if (core_relo_is_enumval_based(relo->kind)) { + err = bpf_core_calc_enumval_relo(relo, local_spec, &res->orig_val); + err = err ?: bpf_core_calc_enumval_relo(relo, targ_spec, &res->new_val); + } + +done: + if (err == -EUCLEAN) { + /* EUCLEAN is used to signal instruction poisoning request */ + res->poison = true; + err = 0; + } else if (err == -EOPNOTSUPP) { + /* EOPNOTSUPP means unknown/unsupported relocation */ + pr_warn("prog '%s': relo #%d: unrecognized CO-RE relocation %s (%d) at insn #%d\n", + prog_name, relo_idx, core_relo_kind_str(relo->kind), + relo->kind, relo->insn_off / 8); + } + + return err; +} + +/* + * Turn instruction for which CO_RE relocation failed into invalid one with + * distinct signature. + */ +static void bpf_core_poison_insn(const char *prog_name, int relo_idx, + int insn_idx, struct bpf_insn *insn) +{ + pr_debug("prog '%s': relo #%d: substituting insn #%d w/ invalid insn\n", + prog_name, relo_idx, insn_idx); + insn->code = BPF_JMP | BPF_CALL; + insn->dst_reg = 0; + insn->src_reg = 0; + insn->off = 0; + /* if this instruction is reachable (not a dead code), + * verifier will complain with the following message: + * invalid func unknown#195896080 + */ + insn->imm = 195896080; /* => 0xbad2310 => "bad relo" */ +} + +static int insn_bpf_size_to_bytes(struct bpf_insn *insn) +{ + switch (BPF_SIZE(insn->code)) { + case BPF_DW: return 8; + case BPF_W: return 4; + case BPF_H: return 2; + case BPF_B: return 1; + default: return -1; + } +} + +static int insn_bytes_to_bpf_size(__u32 sz) +{ + switch (sz) { + case 8: return BPF_DW; + case 4: return BPF_W; + case 2: return BPF_H; + case 1: return BPF_B; + default: return -1; + } +} + +/* + * Patch relocatable BPF instruction. + * + * Patched value is determined by relocation kind and target specification. + * For existence relocations target spec will be NULL if field/type is not found. + * Expected insn->imm value is determined using relocation kind and local + * spec, and is checked before patching instruction. If actual insn->imm value + * is wrong, bail out with error. + * + * Currently supported classes of BPF instruction are: + * 1. rX = <imm> (assignment with immediate operand); + * 2. rX += <imm> (arithmetic operations with immediate operand); + * 3. rX = <imm64> (load with 64-bit immediate value); + * 4. rX = *(T *)(rY + <off>), where T is one of {u8, u16, u32, u64}; + * 5. *(T *)(rX + <off>) = rY, where T is one of {u8, u16, u32, u64}; + * 6. *(T *)(rX + <off>) = <imm>, where T is one of {u8, u16, u32, u64}. + */ +static int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn, + int insn_idx, const struct bpf_core_relo *relo, + int relo_idx, const struct bpf_core_relo_res *res) +{ + __u32 orig_val, new_val; + __u8 class; + + class = BPF_CLASS(insn->code); + + if (res->poison) { +poison: + /* poison second part of ldimm64 to avoid confusing error from + * verifier about "unknown opcode 00" + */ + if (is_ldimm64_insn(insn)) + bpf_core_poison_insn(prog_name, relo_idx, insn_idx + 1, insn + 1); + bpf_core_poison_insn(prog_name, relo_idx, insn_idx, insn); + return 0; + } + + orig_val = res->orig_val; + new_val = res->new_val; + + switch (class) { + case BPF_ALU: + case BPF_ALU64: + if (BPF_SRC(insn->code) != BPF_K) + return -EINVAL; + if (res->validate && insn->imm != orig_val) { + pr_warn("prog '%s': relo #%d: unexpected insn #%d (ALU/ALU64) value: got %u, exp %u -> %u\n", + prog_name, relo_idx, + insn_idx, insn->imm, orig_val, new_val); + return -EINVAL; + } + orig_val = insn->imm; + insn->imm = new_val; + pr_debug("prog '%s': relo #%d: patched insn #%d (ALU/ALU64) imm %u -> %u\n", + prog_name, relo_idx, insn_idx, + orig_val, new_val); + break; + case BPF_LDX: + case BPF_ST: + case BPF_STX: + if (res->validate && insn->off != orig_val) { + pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDX/ST/STX) value: got %u, exp %u -> %u\n", + prog_name, relo_idx, insn_idx, insn->off, orig_val, new_val); + return -EINVAL; + } + if (new_val > SHRT_MAX) { + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) value too big: %u\n", + prog_name, relo_idx, insn_idx, new_val); + return -ERANGE; + } + if (res->fail_memsz_adjust) { + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) accesses field incorrectly. " + "Make sure you are accessing pointers, unsigned integers, or fields of matching type and size.\n", + prog_name, relo_idx, insn_idx); + goto poison; + } + + orig_val = insn->off; + insn->off = new_val; + pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) off %u -> %u\n", + prog_name, relo_idx, insn_idx, orig_val, new_val); + + if (res->new_sz != res->orig_sz) { + int insn_bytes_sz, insn_bpf_sz; + + insn_bytes_sz = insn_bpf_size_to_bytes(insn); + if (insn_bytes_sz != res->orig_sz) { + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) unexpected mem size: got %d, exp %u\n", + prog_name, relo_idx, insn_idx, insn_bytes_sz, res->orig_sz); + return -EINVAL; + } + + insn_bpf_sz = insn_bytes_to_bpf_size(res->new_sz); + if (insn_bpf_sz < 0) { + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) invalid new mem size: %u\n", + prog_name, relo_idx, insn_idx, res->new_sz); + return -EINVAL; + } + + insn->code = BPF_MODE(insn->code) | insn_bpf_sz | BPF_CLASS(insn->code); + pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) mem_sz %u -> %u\n", + prog_name, relo_idx, insn_idx, res->orig_sz, res->new_sz); + } + break; + case BPF_LD: { + __u64 imm; + + if (!is_ldimm64_insn(insn) || + insn[0].src_reg != 0 || insn[0].off != 0 || + insn[1].code != 0 || insn[1].dst_reg != 0 || + insn[1].src_reg != 0 || insn[1].off != 0) { + pr_warn("prog '%s': relo #%d: insn #%d (LDIMM64) has unexpected form\n", + prog_name, relo_idx, insn_idx); + return -EINVAL; + } + + imm = insn[0].imm + ((__u64)insn[1].imm << 32); + if (res->validate && imm != orig_val) { + pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDIMM64) value: got %llu, exp %u -> %u\n", + prog_name, relo_idx, + insn_idx, (unsigned long long)imm, + orig_val, new_val); + return -EINVAL; + } + + insn[0].imm = new_val; + insn[1].imm = 0; /* currently only 32-bit values are supported */ + pr_debug("prog '%s': relo #%d: patched insn #%d (LDIMM64) imm64 %llu -> %u\n", + prog_name, relo_idx, insn_idx, + (unsigned long long)imm, new_val); + break; + } + default: + pr_warn("prog '%s': relo #%d: trying to relocate unrecognized insn #%d, code:0x%x, src:0x%x, dst:0x%x, off:0x%x, imm:0x%x\n", + prog_name, relo_idx, insn_idx, insn->code, + insn->src_reg, insn->dst_reg, insn->off, insn->imm); + return -EINVAL; + } + + return 0; +} + +/* Output spec definition in the format: + * [<type-id>] (<type-name>) + <raw-spec> => <offset>@<spec>, + * where <spec> is a C-syntax view of recorded field access, e.g.: x.a[3].b + */ +static void bpf_core_dump_spec(int level, const struct bpf_core_spec *spec) +{ + const struct btf_type *t; + const struct btf_enum *e; + const char *s; + __u32 type_id; + int i; + + type_id = spec->root_type_id; + t = btf__type_by_id(spec->btf, type_id); + s = btf__name_by_offset(spec->btf, t->name_off); + + libbpf_print(level, "[%u] %s %s", type_id, btf_kind_str(t), str_is_empty(s) ? "<anon>" : s); + + if (core_relo_is_type_based(spec->relo_kind)) + return; + + if (core_relo_is_enumval_based(spec->relo_kind)) { + t = skip_mods_and_typedefs(spec->btf, type_id, NULL); + e = btf_enum(t) + spec->raw_spec[0]; + s = btf__name_by_offset(spec->btf, e->name_off); + + libbpf_print(level, "::%s = %u", s, e->val); + return; + } + + if (core_relo_is_field_based(spec->relo_kind)) { + for (i = 0; i < spec->len; i++) { + if (spec->spec[i].name) + libbpf_print(level, ".%s", spec->spec[i].name); + else if (i > 0 || spec->spec[i].idx > 0) + libbpf_print(level, "[%u]", spec->spec[i].idx); + } + + libbpf_print(level, " ("); + for (i = 0; i < spec->raw_len; i++) + libbpf_print(level, "%s%d", i == 0 ? "" : ":", spec->raw_spec[i]); + + if (spec->bit_offset % 8) + libbpf_print(level, " @ offset %u.%u)", + spec->bit_offset / 8, spec->bit_offset % 8); + else + libbpf_print(level, " @ offset %u)", spec->bit_offset / 8); + return; + } +} + +/* + * CO-RE relocate single instruction. + * + * The outline and important points of the algorithm: + * 1. For given local type, find corresponding candidate target types. + * Candidate type is a type with the same "essential" name, ignoring + * everything after last triple underscore (___). E.g., `sample`, + * `sample___flavor_one`, `sample___flavor_another_one`, are all candidates + * for each other. Names with triple underscore are referred to as + * "flavors" and are useful, among other things, to allow to + * specify/support incompatible variations of the same kernel struct, which + * might differ between different kernel versions and/or build + * configurations. + * + * N.B. Struct "flavors" could be generated by bpftool's BTF-to-C + * converter, when deduplicated BTF of a kernel still contains more than + * one different types with the same name. In that case, ___2, ___3, etc + * are appended starting from second name conflict. But start flavors are + * also useful to be defined "locally", in BPF program, to extract same + * data from incompatible changes between different kernel + * versions/configurations. For instance, to handle field renames between + * kernel versions, one can use two flavors of the struct name with the + * same common name and use conditional relocations to extract that field, + * depending on target kernel version. + * 2. For each candidate type, try to match local specification to this + * candidate target type. Matching involves finding corresponding + * high-level spec accessors, meaning that all named fields should match, + * as well as all array accesses should be within the actual bounds. Also, + * types should be compatible (see bpf_core_fields_are_compat for details). + * 3. It is supported and expected that there might be multiple flavors + * matching the spec. As long as all the specs resolve to the same set of + * offsets across all candidates, there is no error. If there is any + * ambiguity, CO-RE relocation will fail. This is necessary to accomodate + * imprefection of BTF deduplication, which can cause slight duplication of + * the same BTF type, if some directly or indirectly referenced (by + * pointer) type gets resolved to different actual types in different + * object files. If such situation occurs, deduplicated BTF will end up + * with two (or more) structurally identical types, which differ only in + * types they refer to through pointer. This should be OK in most cases and + * is not an error. + * 4. Candidate types search is performed by linearly scanning through all + * types in target BTF. It is anticipated that this is overall more + * efficient memory-wise and not significantly worse (if not better) + * CPU-wise compared to prebuilding a map from all local type names to + * a list of candidate type names. It's also sped up by caching resolved + * list of matching candidates per each local "root" type ID, that has at + * least one bpf_core_relo associated with it. This list is shared + * between multiple relocations for the same type ID and is updated as some + * of the candidates are pruned due to structural incompatibility. + */ +int bpf_core_apply_relo_insn(const char *prog_name, struct bpf_insn *insn, + int insn_idx, + const struct bpf_core_relo *relo, + int relo_idx, + const struct btf *local_btf, + struct bpf_core_cand_list *cands) +{ + struct bpf_core_spec local_spec, cand_spec, targ_spec = {}; + struct bpf_core_relo_res cand_res, targ_res; + const struct btf_type *local_type; + const char *local_name; + __u32 local_id; + const char *spec_str; + int i, j, err; + + local_id = relo->type_id; + local_type = btf__type_by_id(local_btf, local_id); + if (!local_type) + return -EINVAL; + + local_name = btf__name_by_offset(local_btf, local_type->name_off); + if (!local_name) + return -EINVAL; + + spec_str = btf__name_by_offset(local_btf, relo->access_str_off); + if (str_is_empty(spec_str)) + return -EINVAL; + + err = bpf_core_parse_spec(local_btf, local_id, spec_str, relo->kind, &local_spec); + if (err) { + pr_warn("prog '%s': relo #%d: parsing [%d] %s %s + %s failed: %d\n", + prog_name, relo_idx, local_id, btf_kind_str(local_type), + str_is_empty(local_name) ? "<anon>" : local_name, + spec_str, err); + return -EINVAL; + } + + pr_debug("prog '%s': relo #%d: kind <%s> (%d), spec is ", prog_name, + relo_idx, core_relo_kind_str(relo->kind), relo->kind); + bpf_core_dump_spec(LIBBPF_DEBUG, &local_spec); + libbpf_print(LIBBPF_DEBUG, "\n"); + + /* TYPE_ID_LOCAL relo is special and doesn't need candidate search */ + if (relo->kind == BPF_TYPE_ID_LOCAL) { + targ_res.validate = true; + targ_res.poison = false; + targ_res.orig_val = local_spec.root_type_id; + targ_res.new_val = local_spec.root_type_id; + goto patch_insn; + } + + /* libbpf doesn't support candidate search for anonymous types */ + if (str_is_empty(spec_str)) { + pr_warn("prog '%s': relo #%d: <%s> (%d) relocation doesn't support anonymous types\n", + prog_name, relo_idx, core_relo_kind_str(relo->kind), relo->kind); + return -EOPNOTSUPP; + } + + + for (i = 0, j = 0; i < cands->len; i++) { + err = bpf_core_spec_match(&local_spec, cands->cands[i].btf, + cands->cands[i].id, &cand_spec); + if (err < 0) { + pr_warn("prog '%s': relo #%d: error matching candidate #%d ", + prog_name, relo_idx, i); + bpf_core_dump_spec(LIBBPF_WARN, &cand_spec); + libbpf_print(LIBBPF_WARN, ": %d\n", err); + return err; + } + + pr_debug("prog '%s': relo #%d: %s candidate #%d ", prog_name, + relo_idx, err == 0 ? "non-matching" : "matching", i); + bpf_core_dump_spec(LIBBPF_DEBUG, &cand_spec); + libbpf_print(LIBBPF_DEBUG, "\n"); + + if (err == 0) + continue; + + err = bpf_core_calc_relo(prog_name, relo, relo_idx, &local_spec, &cand_spec, &cand_res); + if (err) + return err; + + if (j == 0) { + targ_res = cand_res; + targ_spec = cand_spec; + } else if (cand_spec.bit_offset != targ_spec.bit_offset) { + /* if there are many field relo candidates, they + * should all resolve to the same bit offset + */ + pr_warn("prog '%s': relo #%d: field offset ambiguity: %u != %u\n", + prog_name, relo_idx, cand_spec.bit_offset, + targ_spec.bit_offset); + return -EINVAL; + } else if (cand_res.poison != targ_res.poison || cand_res.new_val != targ_res.new_val) { + /* all candidates should result in the same relocation + * decision and value, otherwise it's dangerous to + * proceed due to ambiguity + */ + pr_warn("prog '%s': relo #%d: relocation decision ambiguity: %s %u != %s %u\n", + prog_name, relo_idx, + cand_res.poison ? "failure" : "success", cand_res.new_val, + targ_res.poison ? "failure" : "success", targ_res.new_val); + return -EINVAL; + } + + cands->cands[j++] = cands->cands[i]; + } + + /* + * For BPF_FIELD_EXISTS relo or when used BPF program has field + * existence checks or kernel version/config checks, it's expected + * that we might not find any candidates. In this case, if field + * wasn't found in any candidate, the list of candidates shouldn't + * change at all, we'll just handle relocating appropriately, + * depending on relo's kind. + */ + if (j > 0) + cands->len = j; + + /* + * If no candidates were found, it might be both a programmer error, + * as well as expected case, depending whether instruction w/ + * relocation is guarded in some way that makes it unreachable (dead + * code) if relocation can't be resolved. This is handled in + * bpf_core_patch_insn() uniformly by replacing that instruction with + * BPF helper call insn (using invalid helper ID). If that instruction + * is indeed unreachable, then it will be ignored and eliminated by + * verifier. If it was an error, then verifier will complain and point + * to a specific instruction number in its log. + */ + if (j == 0) { + pr_debug("prog '%s': relo #%d: no matching targets found\n", + prog_name, relo_idx); + + /* calculate single target relo result explicitly */ + err = bpf_core_calc_relo(prog_name, relo, relo_idx, &local_spec, NULL, &targ_res); + if (err) + return err; + } + +patch_insn: + /* bpf_core_patch_insn() should know how to handle missing targ_spec */ + err = bpf_core_patch_insn(prog_name, insn, insn_idx, relo, relo_idx, &targ_res); + if (err) { + pr_warn("prog '%s': relo #%d: failed to patch insn #%u: %d\n", + prog_name, relo_idx, relo->insn_off / 8, err); + return -EINVAL; + } + + return 0; +} diff --git a/tools/lib/bpf/relo_core.h b/tools/lib/bpf/relo_core.h new file mode 100644 index 000000000000..3b9f8f18346c --- /dev/null +++ b/tools/lib/bpf/relo_core.h @@ -0,0 +1,100 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ +/* Copyright (c) 2019 Facebook */ + +#ifndef __RELO_CORE_H +#define __RELO_CORE_H + +/* bpf_core_relo_kind encodes which aspect of captured field/type/enum value + * has to be adjusted by relocations. + */ +enum bpf_core_relo_kind { + BPF_FIELD_BYTE_OFFSET = 0, /* field byte offset */ + BPF_FIELD_BYTE_SIZE = 1, /* field size in bytes */ + BPF_FIELD_EXISTS = 2, /* field existence in target kernel */ + BPF_FIELD_SIGNED = 3, /* field signedness (0 - unsigned, 1 - signed) */ + BPF_FIELD_LSHIFT_U64 = 4, /* bitfield-specific left bitshift */ + BPF_FIELD_RSHIFT_U64 = 5, /* bitfield-specific right bitshift */ + BPF_TYPE_ID_LOCAL = 6, /* type ID in local BPF object */ + BPF_TYPE_ID_TARGET = 7, /* type ID in target kernel */ + BPF_TYPE_EXISTS = 8, /* type existence in target kernel */ + BPF_TYPE_SIZE = 9, /* type size in bytes */ + BPF_ENUMVAL_EXISTS = 10, /* enum value existence in target kernel */ + BPF_ENUMVAL_VALUE = 11, /* enum value integer value */ +}; + +/* The minimum bpf_core_relo checked by the loader + * + * CO-RE relocation captures the following data: + * - insn_off - instruction offset (in bytes) within a BPF program that needs + * its insn->imm field to be relocated with actual field info; + * - type_id - BTF type ID of the "root" (containing) entity of a relocatable + * type or field; + * - access_str_off - offset into corresponding .BTF string section. String + * interpretation depends on specific relocation kind: + * - for field-based relocations, string encodes an accessed field using + * a sequence of field and array indices, separated by colon (:). It's + * conceptually very close to LLVM's getelementptr ([0]) instruction's + * arguments for identifying offset to a field. + * - for type-based relocations, strings is expected to be just "0"; + * - for enum value-based relocations, string contains an index of enum + * value within its enum type; + * + * Example to provide a better feel. + * + * struct sample { + * int a; + * struct { + * int b[10]; + * }; + * }; + * + * struct sample *s = ...; + * int x = &s->a; // encoded as "0:0" (a is field #0) + * int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1, + * // b is field #0 inside anon struct, accessing elem #5) + * int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array) + * + * type_id for all relocs in this example will capture BTF type id of + * `struct sample`. + * + * Such relocation is emitted when using __builtin_preserve_access_index() + * Clang built-in, passing expression that captures field address, e.g.: + * + * bpf_probe_read(&dst, sizeof(dst), + * __builtin_preserve_access_index(&src->a.b.c)); + * + * In this case Clang will emit field relocation recording necessary data to + * be able to find offset of embedded `a.b.c` field within `src` struct. + * + * [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction + */ +struct bpf_core_relo { + __u32 insn_off; + __u32 type_id; + __u32 access_str_off; + enum bpf_core_relo_kind kind; +}; + +struct bpf_core_cand { + const struct btf *btf; + const struct btf_type *t; + const char *name; + __u32 id; +}; + +/* dynamically sized list of type IDs and its associated struct btf */ +struct bpf_core_cand_list { + struct bpf_core_cand *cands; + int len; +}; + +int bpf_core_apply_relo_insn(const char *prog_name, + struct bpf_insn *insn, int insn_idx, + const struct bpf_core_relo *relo, int relo_idx, + const struct btf *local_btf, + struct bpf_core_cand_list *cands); +int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, + const struct btf *targ_btf, __u32 targ_id); + +size_t bpf_core_essential_name_len(const char *name); +#endif diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index cdecda1ddd36..996d025b8ed8 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -223,10 +223,10 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, free(info_linear); return -1; } - if (btf__get_from_id(info->btf_id, &btf)) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info->btf_id); err = -1; - btf = NULL; goto out; } perf_env__fetch_btf(env, info->btf_id, btf); @@ -296,7 +296,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, out: free(info_linear); - free(btf); + btf__free(btf); return err ? -1 : 0; } @@ -478,7 +478,8 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id) if (btf_id == 0) goto out; - if (btf__get_from_id(btf_id, &btf)) { + btf = btf__load_from_kernel_by_id(btf_id); + if (libbpf_get_error(btf)) { pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, btf_id); goto out; @@ -486,7 +487,7 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id) perf_env__fetch_btf(env, btf_id, btf); out: - free(btf); + btf__free(btf); close(fd); } diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c index 8150e03367bb..ba0f20853651 100644 --- a/tools/perf/util/bpf_counter.c +++ b/tools/perf/util/bpf_counter.c @@ -64,8 +64,8 @@ static char *bpf_target_prog_name(int tgt_fd) struct bpf_prog_info_linear *info_linear; struct bpf_func_info *func_info; const struct btf_type *t; + struct btf *btf = NULL; char *name = NULL; - struct btf *btf; info_linear = bpf_program__get_prog_info_linear( tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO); @@ -74,12 +74,17 @@ static char *bpf_target_prog_name(int tgt_fd) return NULL; } - if (info_linear->info.btf_id == 0 || - btf__get_from_id(info_linear->info.btf_id, &btf)) { + if (info_linear->info.btf_id == 0) { pr_debug("prog FD %d doesn't have valid btf\n", tgt_fd); goto out; } + btf = btf__load_from_kernel_by_id(info_linear->info.btf_id); + if (libbpf_get_error(btf)) { + pr_debug("failed to load btf for prog FD %d\n", tgt_fd); + goto out; + } + func_info = u64_to_ptr(info_linear->info.func_info); t = btf__type_by_id(btf, func_info[0].type_id); if (!t) { @@ -89,6 +94,7 @@ static char *bpf_target_prog_name(int tgt_fd) } name = strdup(btf__name_by_offset(btf, t->name_off)); out: + btf__free(btf); free(info_linear); return name; } diff --git a/tools/testing/selftests/bpf/README.rst b/tools/testing/selftests/bpf/README.rst index 8deec1ca9150..9b17f2867488 100644 --- a/tools/testing/selftests/bpf/README.rst +++ b/tools/testing/selftests/bpf/README.rst @@ -19,6 +19,13 @@ the CI. It builds the kernel (without overwriting your existing Kconfig), recomp bpf selftests, runs them (by default ``tools/testing/selftests/bpf/test_progs``) and saves the resulting output (by default in ``~/.bpf_selftests``). +Script dependencies: +- clang (preferably built from sources, https://github.com/llvm/llvm-project); +- pahole (preferably built from sources, https://git.kernel.org/pub/scm/devel/pahole/pahole.git/); +- qemu; +- docutils (for ``rst2man``); +- libcap-devel. + For more information on about using the script, run: .. code-block:: console diff --git a/tools/testing/selftests/bpf/netcnt_common.h b/tools/testing/selftests/bpf/netcnt_common.h index 81084c1c2c23..0ab1c88041cd 100644 --- a/tools/testing/selftests/bpf/netcnt_common.h +++ b/tools/testing/selftests/bpf/netcnt_common.h @@ -6,19 +6,39 @@ #define MAX_PERCPU_PACKETS 32 -struct percpu_net_cnt { - __u64 packets; - __u64 bytes; +/* sizeof(struct bpf_local_storage_elem): + * + * It really is about 128 bytes on x86_64, but allocate more to account for + * possible layout changes, different architectures, etc. + * The kernel will wrap up to PAGE_SIZE internally anyway. + */ +#define SIZEOF_BPF_LOCAL_STORAGE_ELEM 256 - __u64 prev_ts; +/* Try to estimate kernel's BPF_LOCAL_STORAGE_MAX_VALUE_SIZE: */ +#define BPF_LOCAL_STORAGE_MAX_VALUE_SIZE (0xFFFF - \ + SIZEOF_BPF_LOCAL_STORAGE_ELEM) - __u64 prev_packets; - __u64 prev_bytes; +#define PCPU_MIN_UNIT_SIZE 32768 + +union percpu_net_cnt { + struct { + __u64 packets; + __u64 bytes; + + __u64 prev_ts; + + __u64 prev_packets; + __u64 prev_bytes; + }; + __u8 data[PCPU_MIN_UNIT_SIZE]; }; -struct net_cnt { - __u64 packets; - __u64 bytes; +union net_cnt { + struct { + __u64 packets; + __u64 bytes; + }; + __u8 data[BPF_LOCAL_STORAGE_MAX_VALUE_SIZE]; }; #endif diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c index 2060bc122c53..26468a8f44f3 100644 --- a/tools/testing/selftests/bpf/network_helpers.c +++ b/tools/testing/selftests/bpf/network_helpers.c @@ -66,17 +66,13 @@ int settimeo(int fd, int timeout_ms) #define save_errno_close(fd) ({ int __save = errno; close(fd); errno = __save; }) -int start_server(int family, int type, const char *addr_str, __u16 port, - int timeout_ms) +static int __start_server(int type, const struct sockaddr *addr, + socklen_t addrlen, int timeout_ms, bool reuseport) { - struct sockaddr_storage addr = {}; - socklen_t len; + int on = 1; int fd; - if (make_sockaddr(family, addr_str, port, &addr, &len)) - return -1; - - fd = socket(family, type, 0); + fd = socket(addr->sa_family, type, 0); if (fd < 0) { log_err("Failed to create server socket"); return -1; @@ -85,7 +81,13 @@ int start_server(int family, int type, const char *addr_str, __u16 port, if (settimeo(fd, timeout_ms)) goto error_close; - if (bind(fd, (const struct sockaddr *)&addr, len) < 0) { + if (reuseport && + setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &on, sizeof(on))) { + log_err("Failed to set SO_REUSEPORT"); + return -1; + } + + if (bind(fd, addr, addrlen) < 0) { log_err("Failed to bind socket"); goto error_close; } @@ -104,6 +106,69 @@ error_close: return -1; } +int start_server(int family, int type, const char *addr_str, __u16 port, + int timeout_ms) +{ + struct sockaddr_storage addr; + socklen_t addrlen; + + if (make_sockaddr(family, addr_str, port, &addr, &addrlen)) + return -1; + + return __start_server(type, (struct sockaddr *)&addr, + addrlen, timeout_ms, false); +} + +int *start_reuseport_server(int family, int type, const char *addr_str, + __u16 port, int timeout_ms, unsigned int nr_listens) +{ + struct sockaddr_storage addr; + unsigned int nr_fds = 0; + socklen_t addrlen; + int *fds; + + if (!nr_listens) + return NULL; + + if (make_sockaddr(family, addr_str, port, &addr, &addrlen)) + return NULL; + + fds = malloc(sizeof(*fds) * nr_listens); + if (!fds) + return NULL; + + fds[0] = __start_server(type, (struct sockaddr *)&addr, addrlen, + timeout_ms, true); + if (fds[0] == -1) + goto close_fds; + nr_fds = 1; + + if (getsockname(fds[0], (struct sockaddr *)&addr, &addrlen)) + goto close_fds; + + for (; nr_fds < nr_listens; nr_fds++) { + fds[nr_fds] = __start_server(type, (struct sockaddr *)&addr, + addrlen, timeout_ms, true); + if (fds[nr_fds] == -1) + goto close_fds; + } + + return fds; + +close_fds: + free_fds(fds, nr_fds); + return NULL; +} + +void free_fds(int *fds, unsigned int nr_close_fds) +{ + if (fds) { + while (nr_close_fds) + close(fds[--nr_close_fds]); + free(fds); + } +} + int fastopen_connect(int server_fd, const char *data, unsigned int data_len, int timeout_ms) { @@ -217,6 +282,7 @@ int make_sockaddr(int family, const char *addr_str, __u16 port, if (family == AF_INET) { struct sockaddr_in *sin = (void *)addr; + memset(addr, 0, sizeof(*sin)); sin->sin_family = AF_INET; sin->sin_port = htons(port); if (addr_str && @@ -230,6 +296,7 @@ int make_sockaddr(int family, const char *addr_str, __u16 port, } else if (family == AF_INET6) { struct sockaddr_in6 *sin6 = (void *)addr; + memset(addr, 0, sizeof(*sin6)); sin6->sin6_family = AF_INET6; sin6->sin6_port = htons(port); if (addr_str && diff --git a/tools/testing/selftests/bpf/network_helpers.h b/tools/testing/selftests/bpf/network_helpers.h index 5e0d51c07b63..d60bc2897770 100644 --- a/tools/testing/selftests/bpf/network_helpers.h +++ b/tools/testing/selftests/bpf/network_helpers.h @@ -36,6 +36,10 @@ extern struct ipv6_packet pkt_v6; int settimeo(int fd, int timeout_ms); int start_server(int family, int type, const char *addr, __u16 port, int timeout_ms); +int *start_reuseport_server(int family, int type, const char *addr_str, + __u16 port, int timeout_ms, + unsigned int nr_listens); +void free_fds(int *fds, unsigned int nr_close_fds); int connect_to_fd(int server_fd, int timeout_ms); int connect_fd_to_fd(int client_fd, int server_fd, int timeout_ms); int fastopen_connect(int server_fd, const char *data, unsigned int data_len, diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter_setsockopt.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter_setsockopt.c new file mode 100644 index 000000000000..85babb0487b3 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter_setsockopt.c @@ -0,0 +1,226 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ +#define _GNU_SOURCE +#include <sched.h> +#include <test_progs.h> +#include "network_helpers.h" +#include "bpf_dctcp.skel.h" +#include "bpf_cubic.skel.h" +#include "bpf_iter_setsockopt.skel.h" + +static int create_netns(void) +{ + if (!ASSERT_OK(unshare(CLONE_NEWNET), "create netns")) + return -1; + + if (!ASSERT_OK(system("ip link set dev lo up"), "bring up lo")) + return -1; + + return 0; +} + +static unsigned int set_bpf_cubic(int *fds, unsigned int nr_fds) +{ + unsigned int i; + + for (i = 0; i < nr_fds; i++) { + if (setsockopt(fds[i], SOL_TCP, TCP_CONGESTION, "bpf_cubic", + sizeof("bpf_cubic"))) + return i; + } + + return nr_fds; +} + +static unsigned int check_bpf_dctcp(int *fds, unsigned int nr_fds) +{ + char tcp_cc[16]; + socklen_t optlen = sizeof(tcp_cc); + unsigned int i; + + for (i = 0; i < nr_fds; i++) { + if (getsockopt(fds[i], SOL_TCP, TCP_CONGESTION, + tcp_cc, &optlen) || + strcmp(tcp_cc, "bpf_dctcp")) + return i; + } + + return nr_fds; +} + +static int *make_established(int listen_fd, unsigned int nr_est, + int **paccepted_fds) +{ + int *est_fds, *accepted_fds; + unsigned int i; + + est_fds = malloc(sizeof(*est_fds) * nr_est); + if (!est_fds) + return NULL; + + accepted_fds = malloc(sizeof(*accepted_fds) * nr_est); + if (!accepted_fds) { + free(est_fds); + return NULL; + } + + for (i = 0; i < nr_est; i++) { + est_fds[i] = connect_to_fd(listen_fd, 0); + if (est_fds[i] == -1) + break; + if (set_bpf_cubic(&est_fds[i], 1) != 1) { + close(est_fds[i]); + break; + } + + accepted_fds[i] = accept(listen_fd, NULL, 0); + if (accepted_fds[i] == -1) { + close(est_fds[i]); + break; + } + } + + if (!ASSERT_EQ(i, nr_est, "create established fds")) { + free_fds(accepted_fds, i); + free_fds(est_fds, i); + return NULL; + } + + *paccepted_fds = accepted_fds; + return est_fds; +} + +static unsigned short get_local_port(int fd) +{ + struct sockaddr_in6 addr; + socklen_t addrlen = sizeof(addr); + + if (!getsockname(fd, &addr, &addrlen)) + return ntohs(addr.sin6_port); + + return 0; +} + +static void do_bpf_iter_setsockopt(struct bpf_iter_setsockopt *iter_skel, + bool random_retry) +{ + int *reuse_listen_fds = NULL, *accepted_fds = NULL, *est_fds = NULL; + unsigned int nr_reuse_listens = 256, nr_est = 256; + int err, iter_fd = -1, listen_fd = -1; + char buf; + + /* Prepare non-reuseport listen_fd */ + listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0); + if (!ASSERT_GE(listen_fd, 0, "start_server")) + return; + if (!ASSERT_EQ(set_bpf_cubic(&listen_fd, 1), 1, + "set listen_fd to cubic")) + goto done; + iter_skel->bss->listen_hport = get_local_port(listen_fd); + if (!ASSERT_NEQ(iter_skel->bss->listen_hport, 0, + "get_local_port(listen_fd)")) + goto done; + + /* Connect to non-reuseport listen_fd */ + est_fds = make_established(listen_fd, nr_est, &accepted_fds); + if (!ASSERT_OK_PTR(est_fds, "create established")) + goto done; + + /* Prepare reuseport listen fds */ + reuse_listen_fds = start_reuseport_server(AF_INET6, SOCK_STREAM, + "::1", 0, 0, + nr_reuse_listens); + if (!ASSERT_OK_PTR(reuse_listen_fds, "start_reuseport_server")) + goto done; + if (!ASSERT_EQ(set_bpf_cubic(reuse_listen_fds, nr_reuse_listens), + nr_reuse_listens, "set reuse_listen_fds to cubic")) + goto done; + iter_skel->bss->reuse_listen_hport = get_local_port(reuse_listen_fds[0]); + if (!ASSERT_NEQ(iter_skel->bss->reuse_listen_hport, 0, + "get_local_port(reuse_listen_fds[0])")) + goto done; + + /* Run bpf tcp iter to switch from bpf_cubic to bpf_dctcp */ + iter_skel->bss->random_retry = random_retry; + iter_fd = bpf_iter_create(bpf_link__fd(iter_skel->links.change_tcp_cc)); + if (!ASSERT_GE(iter_fd, 0, "create iter_fd")) + goto done; + + while ((err = read(iter_fd, &buf, sizeof(buf))) == -1 && + errno == EAGAIN) + ; + if (!ASSERT_OK(err, "read iter error")) + goto done; + + /* Check reuseport listen fds for dctcp */ + ASSERT_EQ(check_bpf_dctcp(reuse_listen_fds, nr_reuse_listens), + nr_reuse_listens, + "check reuse_listen_fds dctcp"); + + /* Check non reuseport listen fd for dctcp */ + ASSERT_EQ(check_bpf_dctcp(&listen_fd, 1), 1, + "check listen_fd dctcp"); + + /* Check established fds for dctcp */ + ASSERT_EQ(check_bpf_dctcp(est_fds, nr_est), nr_est, + "check est_fds dctcp"); + + /* Check accepted fds for dctcp */ + ASSERT_EQ(check_bpf_dctcp(accepted_fds, nr_est), nr_est, + "check accepted_fds dctcp"); + +done: + if (iter_fd != -1) + close(iter_fd); + if (listen_fd != -1) + close(listen_fd); + free_fds(reuse_listen_fds, nr_reuse_listens); + free_fds(accepted_fds, nr_est); + free_fds(est_fds, nr_est); +} + +void test_bpf_iter_setsockopt(void) +{ + struct bpf_iter_setsockopt *iter_skel = NULL; + struct bpf_cubic *cubic_skel = NULL; + struct bpf_dctcp *dctcp_skel = NULL; + struct bpf_link *cubic_link = NULL; + struct bpf_link *dctcp_link = NULL; + + if (create_netns()) + return; + + /* Load iter_skel */ + iter_skel = bpf_iter_setsockopt__open_and_load(); + if (!ASSERT_OK_PTR(iter_skel, "iter_skel")) + return; + iter_skel->links.change_tcp_cc = bpf_program__attach_iter(iter_skel->progs.change_tcp_cc, NULL); + if (!ASSERT_OK_PTR(iter_skel->links.change_tcp_cc, "attach iter")) + goto done; + + /* Load bpf_cubic */ + cubic_skel = bpf_cubic__open_and_load(); + if (!ASSERT_OK_PTR(cubic_skel, "cubic_skel")) + goto done; + cubic_link = bpf_map__attach_struct_ops(cubic_skel->maps.cubic); + if (!ASSERT_OK_PTR(cubic_link, "cubic_link")) + goto done; + + /* Load bpf_dctcp */ + dctcp_skel = bpf_dctcp__open_and_load(); + if (!ASSERT_OK_PTR(dctcp_skel, "dctcp_skel")) + goto done; + dctcp_link = bpf_map__attach_struct_ops(dctcp_skel->maps.dctcp); + if (!ASSERT_OK_PTR(dctcp_link, "dctcp_link")) + goto done; + + do_bpf_iter_setsockopt(iter_skel, true); + do_bpf_iter_setsockopt(iter_skel, false); + +done: + bpf_link__destroy(cubic_link); + bpf_link__destroy(dctcp_link); + bpf_cubic__destroy(cubic_skel); + bpf_dctcp__destroy(dctcp_skel); + bpf_iter_setsockopt__destroy(iter_skel); +} diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c index 857e3f26086f..649f87382c8d 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf.c +++ b/tools/testing/selftests/bpf/prog_tests/btf.c @@ -4350,7 +4350,8 @@ static void do_test_file(unsigned int test_num) goto done; } - err = btf__get_from_id(info.btf_id, &btf); + btf = btf__load_from_kernel_by_id(info.btf_id); + err = libbpf_get_error(btf); if (CHECK(err, "cannot get btf from kernel, err: %d", err)) goto done; @@ -4386,6 +4387,7 @@ skip: fprintf(stderr, "OK"); done: + btf__free(btf); free(func_info); bpf_object__close(obj); } diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c index 1b90e684ff13..52ccf0cf35e1 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c @@ -232,7 +232,593 @@ err_out: btf__free(btf); } +#define STRSIZE 4096 + +static void btf_dump_snprintf(void *ctx, const char *fmt, va_list args) +{ + char *s = ctx, new[STRSIZE]; + + vsnprintf(new, STRSIZE, fmt, args); + if (strlen(s) < STRSIZE) + strncat(s, new, STRSIZE - strlen(s) - 1); +} + +static int btf_dump_data(struct btf *btf, struct btf_dump *d, + char *name, char *prefix, __u64 flags, void *ptr, + size_t ptr_sz, char *str, const char *expected_val) +{ + DECLARE_LIBBPF_OPTS(btf_dump_type_data_opts, opts); + size_t type_sz; + __s32 type_id; + int ret = 0; + + if (flags & BTF_F_COMPACT) + opts.compact = true; + if (flags & BTF_F_NONAME) + opts.skip_names = true; + if (flags & BTF_F_ZERO) + opts.emit_zeroes = true; + if (prefix) { + ASSERT_STRNEQ(name, prefix, strlen(prefix), + "verify prefix match"); + name += strlen(prefix) + 1; + } + type_id = btf__find_by_name(btf, name); + if (!ASSERT_GE(type_id, 0, "find type id")) + return -ENOENT; + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + ret = btf_dump__dump_type_data(d, type_id, ptr, ptr_sz, &opts); + if (type_sz <= ptr_sz) { + if (!ASSERT_EQ(ret, type_sz, "failed/unexpected type_sz")) + return -EINVAL; + } else { + if (!ASSERT_EQ(ret, -E2BIG, "failed to return -E2BIG")) + return -EINVAL; + } + if (!ASSERT_STREQ(str, expected_val, "ensure expected/actual match")) + return -EFAULT; + return 0; +} + +#define TEST_BTF_DUMP_DATA(_b, _d, _prefix, _str, _type, _flags, \ + _expected, ...) \ + do { \ + char __ptrtype[64] = #_type; \ + char *_ptrtype = (char *)__ptrtype; \ + _type _ptrdata = __VA_ARGS__; \ + void *_ptr = &_ptrdata; \ + \ + (void) btf_dump_data(_b, _d, _ptrtype, _prefix, _flags, \ + _ptr, sizeof(_type), _str, \ + _expected); \ + } while (0) + +/* Use where expected data string matches its stringified declaration */ +#define TEST_BTF_DUMP_DATA_C(_b, _d, _prefix, _str, _type, _flags, \ + ...) \ + TEST_BTF_DUMP_DATA(_b, _d, _prefix, _str, _type, _flags, \ + "(" #_type ")" #__VA_ARGS__, __VA_ARGS__) + +/* overflow test; pass typesize < expected type size, ensure E2BIG returned */ +#define TEST_BTF_DUMP_DATA_OVER(_b, _d, _prefix, _str, _type, _type_sz, \ + _expected, ...) \ + do { \ + char __ptrtype[64] = #_type; \ + char *_ptrtype = (char *)__ptrtype; \ + _type _ptrdata = __VA_ARGS__; \ + void *_ptr = &_ptrdata; \ + \ + (void) btf_dump_data(_b, _d, _ptrtype, _prefix, 0, \ + _ptr, _type_sz, _str, _expected); \ + } while (0) + +#define TEST_BTF_DUMP_VAR(_b, _d, _prefix, _str, _var, _type, _flags, \ + _expected, ...) \ + do { \ + _type _ptrdata = __VA_ARGS__; \ + void *_ptr = &_ptrdata; \ + \ + (void) btf_dump_data(_b, _d, _var, _prefix, _flags, \ + _ptr, sizeof(_type), _str, \ + _expected); \ + } while (0) + +static void test_btf_dump_int_data(struct btf *btf, struct btf_dump *d, + char *str) +{ +#ifdef __SIZEOF_INT128__ + __int128 i = 0xffffffffffffffff; + + /* this dance is required because we cannot directly initialize + * a 128-bit value to anything larger than a 64-bit value. + */ + i = (i << 64) | (i - 1); +#endif + /* simple int */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, int, BTF_F_COMPACT, 1234); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_NONAME, + "1234", 1234); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, 0, "(int)1234", 1234); + + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT, "(int)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_NONAME, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_ZERO, + "(int)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, int, BTF_F_COMPACT, -4567); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_NONAME, + "-4567", -4567); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, 0, "(int)-4567", -4567); + + TEST_BTF_DUMP_DATA_OVER(btf, d, NULL, str, int, sizeof(int)-1, "", 1); + +#ifdef __SIZEOF_INT128__ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, __int128, BTF_F_COMPACT, + "(__int128)0xffffffffffffffff", + 0xffffffffffffffff); + ASSERT_OK(btf_dump_data(btf, d, "__int128", NULL, 0, &i, 16, str, + "(__int128)0xfffffffffffffffffffffffffffffffe"), + "dump __int128"); +#endif +} + +static void test_btf_dump_float_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + float t1 = 1.234567; + float t2 = -1.234567; + float t3 = 0.0; + double t4 = 5.678912; + double t5 = -5.678912; + double t6 = 0.0; + long double t7 = 9.876543; + long double t8 = -9.876543; + long double t9 = 0.0; + + /* since the kernel does not likely have any float types in its BTF, we + * will need to add some of various sizes. + */ + + ASSERT_GT(btf__add_float(btf, "test_float", 4), 0, "add float"); + ASSERT_OK(btf_dump_data(btf, d, "test_float", NULL, 0, &t1, 4, str, + "(test_float)1.234567"), "dump float"); + ASSERT_OK(btf_dump_data(btf, d, "test_float", NULL, 0, &t2, 4, str, + "(test_float)-1.234567"), "dump float"); + ASSERT_OK(btf_dump_data(btf, d, "test_float", NULL, 0, &t3, 4, str, + "(test_float)0.000000"), "dump float"); + + ASSERT_GT(btf__add_float(btf, "test_double", 8), 0, "add_double"); + ASSERT_OK(btf_dump_data(btf, d, "test_double", NULL, 0, &t4, 8, str, + "(test_double)5.678912"), "dump double"); + ASSERT_OK(btf_dump_data(btf, d, "test_double", NULL, 0, &t5, 8, str, + "(test_double)-5.678912"), "dump double"); + ASSERT_OK(btf_dump_data(btf, d, "test_double", NULL, 0, &t6, 8, str, + "(test_double)0.000000"), "dump double"); + + ASSERT_GT(btf__add_float(btf, "test_long_double", 16), 0, "add long double"); + ASSERT_OK(btf_dump_data(btf, d, "test_long_double", NULL, 0, &t7, 16, + str, "(test_long_double)9.876543"), + "dump long_double"); + ASSERT_OK(btf_dump_data(btf, d, "test_long_double", NULL, 0, &t8, 16, + str, "(test_long_double)-9.876543"), + "dump long_double"); + ASSERT_OK(btf_dump_data(btf, d, "test_long_double", NULL, 0, &t9, 16, + str, "(test_long_double)0.000000"), + "dump long_double"); +} + +static void test_btf_dump_char_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + /* simple char */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, char, BTF_F_COMPACT, 100); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_NONAME, + "100", 100); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, 0, "(char)100", 100); + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT, + "(char)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_NONAME, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_ZERO, + "(char)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, 0, "(char)0", 0); + + TEST_BTF_DUMP_DATA_OVER(btf, d, NULL, str, char, sizeof(char)-1, "", 100); +} + +static void test_btf_dump_typedef_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + /* simple typedef */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, uint64_t, BTF_F_COMPACT, 100); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT | BTF_F_NONAME, + "1", 1); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, 0, "(u64)1", 1); + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT, "(u64)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT | BTF_F_NONAME, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT | BTF_F_ZERO, + "(u64)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, 0, "(u64)0", 0); + + /* typedef struct */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, atomic_t, BTF_F_COMPACT, + {.counter = (int)1,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT | BTF_F_NONAME, + "{1,}", { .counter = 1 }); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, 0, +"(atomic_t){\n" +" .counter = (int)1,\n" +"}", + {.counter = 1,}); + /* typedef with 0 value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT, "(atomic_t){}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT | BTF_F_NONAME, + "{}", {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, 0, +"(atomic_t){\n" +"}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT | BTF_F_ZERO, + "(atomic_t){.counter = (int)0,}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "{0,}", {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_ZERO, +"(atomic_t){\n" +" .counter = (int)0,\n" +"}", + { .counter = 0,}); + + /* overflow should show type but not value since it overflows */ + TEST_BTF_DUMP_DATA_OVER(btf, d, NULL, str, atomic_t, sizeof(atomic_t)-1, + "(atomic_t){\n", { .counter = 1}); +} + +static void test_btf_dump_enum_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + /* enum where enum value does (and does not) exist */ + TEST_BTF_DUMP_DATA_C(btf, d, "enum", str, enum bpf_cmd, BTF_F_COMPACT, + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, BTF_F_COMPACT, + "(enum bpf_cmd)BPF_MAP_CREATE", 0); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME, + "BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, 0, + "(enum bpf_cmd)BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "BPF_MAP_CREATE", 0); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_ZERO, + "(enum bpf_cmd)BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "BPF_MAP_CREATE", BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA_C(btf, d, "enum", str, enum bpf_cmd, BTF_F_COMPACT, 2000); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME, + "2000", 2000); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, 0, + "(enum bpf_cmd)2000", 2000); + + TEST_BTF_DUMP_DATA_OVER(btf, d, "enum", str, enum bpf_cmd, + sizeof(enum bpf_cmd) - 1, "", BPF_MAP_CREATE); +} + +static void test_btf_dump_struct_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + DECLARE_LIBBPF_OPTS(btf_dump_type_data_opts, opts); + char zero_data[512] = { }; + char type_data[512]; + void *fops = type_data; + void *skb = type_data; + size_t type_sz; + __s32 type_id; + char *cmpstr; + int ret; + + memset(type_data, 255, sizeof(type_data)); + + /* simple struct */ + TEST_BTF_DUMP_DATA_C(btf, d, "struct", str, struct btf_enum, BTF_F_COMPACT, + {.name_off = (__u32)3,.val = (__s32)-1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME, + "{3,-1,}", + { .name_off = 3, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, 0, +"(struct btf_enum){\n" +" .name_off = (__u32)3,\n" +" .val = (__s32)-1,\n" +"}", + { .name_off = 3, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME, + "{-1,}", + { .name_off = 0, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "{0,-1,}", + { .name_off = 0, .val = -1,}); + /* empty struct should be printed */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, BTF_F_COMPACT, + "(struct btf_enum){}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME, + "{}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, 0, +"(struct btf_enum){\n" +"}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_ZERO, + "(struct btf_enum){.name_off = (__u32)0,.val = (__s32)0,}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_ZERO, +"(struct btf_enum){\n" +" .name_off = (__u32)0,\n" +" .val = (__s32)0,\n" +"}", + { .name_off = 0, .val = 0,}); + + /* struct with pointers */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, BTF_F_COMPACT, + "(struct list_head){.next = (struct list_head *)0x1,}", + { .next = (struct list_head *)1 }); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, 0, +"(struct list_head){\n" +" .next = (struct list_head *)0x1,\n" +"}", + { .next = (struct list_head *)1 }); + /* NULL pointer should not be displayed */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, BTF_F_COMPACT, + "(struct list_head){}", + { .next = (struct list_head *)0 }); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, 0, +"(struct list_head){\n" +"}", + { .next = (struct list_head *)0 }); + + /* struct with function pointers */ + type_id = btf__find_by_name(btf, "file_operations"); + if (ASSERT_GT(type_id, 0, "find type id")) { + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + + ret = btf_dump__dump_type_data(d, type_id, fops, type_sz, &opts); + ASSERT_EQ(ret, type_sz, + "unexpected return value dumping file_operations"); + cmpstr = +"(struct file_operations){\n" +" .owner = (struct module *)0xffffffffffffffff,\n" +" .llseek = (loff_t (*)(struct file *, loff_t, int))0xffffffffffffffff,"; + + ASSERT_STRNEQ(str, cmpstr, strlen(cmpstr), "file_operations"); + } + + /* struct with char array */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, BTF_F_COMPACT, + "(struct bpf_prog_info){.name = (char[16])['f','o','o',],}", + { .name = "foo",}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, + BTF_F_COMPACT | BTF_F_NONAME, + "{['f','o','o',],}", + {.name = "foo",}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, 0, +"(struct bpf_prog_info){\n" +" .name = (char[16])[\n" +" 'f',\n" +" 'o',\n" +" 'o',\n" +" ],\n" +"}", + {.name = "foo",}); + /* leading null char means do not display string */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, BTF_F_COMPACT, + "(struct bpf_prog_info){}", + {.name = {'\0', 'f', 'o', 'o'}}); + /* handle non-printable characters */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, BTF_F_COMPACT, + "(struct bpf_prog_info){.name = (char[16])[1,2,3,],}", + { .name = {1, 2, 3, 0}}); + + /* struct with non-char array */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, BTF_F_COMPACT, + "(struct __sk_buff){.cb = (__u32[5])[1,2,3,4,5,],}", + { .cb = {1, 2, 3, 4, 5,},}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, + BTF_F_COMPACT | BTF_F_NONAME, + "{[1,2,3,4,5,],}", + { .cb = { 1, 2, 3, 4, 5},}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, 0, +"(struct __sk_buff){\n" +" .cb = (__u32[5])[\n" +" 1,\n" +" 2,\n" +" 3,\n" +" 4,\n" +" 5,\n" +" ],\n" +"}", + { .cb = { 1, 2, 3, 4, 5},}); + /* For non-char, arrays, show non-zero values only */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, BTF_F_COMPACT, + "(struct __sk_buff){.cb = (__u32[5])[0,0,1,0,0,],}", + { .cb = { 0, 0, 1, 0, 0},}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, 0, +"(struct __sk_buff){\n" +" .cb = (__u32[5])[\n" +" 0,\n" +" 0,\n" +" 1,\n" +" 0,\n" +" 0,\n" +" ],\n" +"}", + { .cb = { 0, 0, 1, 0, 0},}); + + /* struct with bitfields */ + TEST_BTF_DUMP_DATA_C(btf, d, "struct", str, struct bpf_insn, BTF_F_COMPACT, + {.code = (__u8)1,.dst_reg = (__u8)0x2,.src_reg = (__u8)0x3,.off = (__s16)4,.imm = (__s32)5,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_insn, + BTF_F_COMPACT | BTF_F_NONAME, + "{1,0x2,0x3,4,5,}", + { .code = 1, .dst_reg = 0x2, .src_reg = 0x3, .off = 4, + .imm = 5,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_insn, 0, +"(struct bpf_insn){\n" +" .code = (__u8)1,\n" +" .dst_reg = (__u8)0x2,\n" +" .src_reg = (__u8)0x3,\n" +" .off = (__s16)4,\n" +" .imm = (__s32)5,\n" +"}", + {.code = 1, .dst_reg = 2, .src_reg = 3, .off = 4, .imm = 5}); + + /* zeroed bitfields should not be displayed */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_insn, BTF_F_COMPACT, + "(struct bpf_insn){.dst_reg = (__u8)0x1,}", + { .code = 0, .dst_reg = 1}); + + /* struct with enum bitfield */ + type_id = btf__find_by_name(btf, "fs_context"); + if (ASSERT_GT(type_id, 0, "find fs_context")) { + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + + opts.emit_zeroes = true; + ret = btf_dump__dump_type_data(d, type_id, zero_data, type_sz, &opts); + ASSERT_EQ(ret, type_sz, + "unexpected return value dumping fs_context"); + + ASSERT_NEQ(strstr(str, "FS_CONTEXT_FOR_MOUNT"), NULL, + "bitfield value not present"); + } + + /* struct with nested anon union */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_sock_ops, BTF_F_COMPACT, + "(struct bpf_sock_ops){.op = (__u32)1,(union){.args = (__u32[4])[1,2,3,4,],.reply = (__u32)1,.replylong = (__u32[4])[1,2,3,4,],},}", + { .op = 1, .args = { 1, 2, 3, 4}}); + + /* union with nested struct */ + TEST_BTF_DUMP_DATA(btf, d, "union", str, union bpf_iter_link_info, BTF_F_COMPACT, + "(union bpf_iter_link_info){.map = (struct){.map_fd = (__u32)1,},}", + { .map = { .map_fd = 1 }}); + + /* struct skb with nested structs/unions; because type output is so + * complex, we don't do a string comparison, just verify we return + * the type size as the amount of data displayed. + */ + type_id = btf__find_by_name(btf, "sk_buff"); + if (ASSERT_GT(type_id, 0, "find struct sk_buff")) { + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + + ret = btf_dump__dump_type_data(d, type_id, skb, type_sz, &opts); + ASSERT_EQ(ret, type_sz, + "unexpected return value dumping sk_buff"); + } + + /* overflow bpf_sock_ops struct with final element nonzero/zero. + * Regardless of the value of the final field, we don't have all the + * data we need to display it, so we should trigger an overflow. + * In other words oveflow checking should trump "is field zero?" + * checks because if we've overflowed, it shouldn't matter what the + * field is - we can't trust its value so shouldn't display it. + */ + TEST_BTF_DUMP_DATA_OVER(btf, d, "struct", str, struct bpf_sock_ops, + sizeof(struct bpf_sock_ops) - 1, + "(struct bpf_sock_ops){\n\t.op = (__u32)1,\n", + { .op = 1, .skb_tcp_flags = 2}); + TEST_BTF_DUMP_DATA_OVER(btf, d, "struct", str, struct bpf_sock_ops, + sizeof(struct bpf_sock_ops) - 1, + "(struct bpf_sock_ops){\n\t.op = (__u32)1,\n", + { .op = 1, .skb_tcp_flags = 0}); +} + +static void test_btf_dump_var_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + TEST_BTF_DUMP_VAR(btf, d, NULL, str, "cpu_number", int, BTF_F_COMPACT, + "int cpu_number = (int)100", 100); + TEST_BTF_DUMP_VAR(btf, d, NULL, str, "cpu_profile_flip", int, BTF_F_COMPACT, + "static int cpu_profile_flip = (int)2", 2); +} + +static void test_btf_datasec(struct btf *btf, struct btf_dump *d, char *str, + const char *name, const char *expected_val, + void *data, size_t data_sz) +{ + DECLARE_LIBBPF_OPTS(btf_dump_type_data_opts, opts); + int ret = 0, cmp; + size_t secsize; + __s32 type_id; + + opts.compact = true; + + type_id = btf__find_by_name(btf, name); + if (!ASSERT_GT(type_id, 0, "find type id")) + return; + + secsize = btf__resolve_size(btf, type_id); + ASSERT_EQ(secsize, 0, "verify section size"); + + str[0] = '\0'; + ret = btf_dump__dump_type_data(d, type_id, data, data_sz, &opts); + ASSERT_EQ(ret, 0, "unexpected return value"); + + cmp = strcmp(str, expected_val); + ASSERT_EQ(cmp, 0, "ensure expected/actual match"); +} + +static void test_btf_dump_datasec_data(char *str) +{ + struct btf *btf = btf__parse("xdping_kern.o", NULL); + struct btf_dump_opts opts = { .ctx = str }; + char license[4] = "GPL"; + struct btf_dump *d; + + if (!ASSERT_OK_PTR(btf, "xdping_kern.o BTF not found")) + return; + + d = btf_dump__new(btf, NULL, &opts, btf_dump_snprintf); + if (!ASSERT_OK_PTR(d, "could not create BTF dump")) + return; + + test_btf_datasec(btf, d, str, "license", + "SEC(\"license\") char[4] _license = (char[4])['G','P','L',];", + license, sizeof(license)); +} + void test_btf_dump() { + char str[STRSIZE]; + struct btf_dump_opts opts = { .ctx = str }; + struct btf_dump *d; + struct btf *btf; int i; for (i = 0; i < ARRAY_SIZE(btf_dump_test_cases); i++) { @@ -245,4 +831,33 @@ void test_btf_dump() { } if (test__start_subtest("btf_dump: incremental")) test_btf_dump_incremental(); + + btf = libbpf_find_kernel_btf(); + if (!ASSERT_OK_PTR(btf, "no kernel BTF found")) + return; + + d = btf_dump__new(btf, NULL, &opts, btf_dump_snprintf); + if (!ASSERT_OK_PTR(d, "could not create BTF dump")) + return; + + /* Verify type display for various types. */ + if (test__start_subtest("btf_dump: int_data")) + test_btf_dump_int_data(btf, d, str); + if (test__start_subtest("btf_dump: float_data")) + test_btf_dump_float_data(btf, d, str); + if (test__start_subtest("btf_dump: char_data")) + test_btf_dump_char_data(btf, d, str); + if (test__start_subtest("btf_dump: typedef_data")) + test_btf_dump_typedef_data(btf, d, str); + if (test__start_subtest("btf_dump: enum_data")) + test_btf_dump_enum_data(btf, d, str); + if (test__start_subtest("btf_dump: struct_data")) + test_btf_dump_struct_data(btf, d, str); + if (test__start_subtest("btf_dump: var_data")) + test_btf_dump_var_data(btf, d, str); + btf_dump__free(d); + btf__free(btf); + + if (test__start_subtest("btf_dump: datasec_data")) + test_btf_dump_datasec_data(str); } diff --git a/tools/testing/selftests/bpf/prog_tests/core_autosize.c b/tools/testing/selftests/bpf/prog_tests/core_autosize.c index 981c251453d9..3d4b2a358d47 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_autosize.c +++ b/tools/testing/selftests/bpf/prog_tests/core_autosize.c @@ -53,8 +53,8 @@ void test_core_autosize(void) char btf_file[] = "/tmp/core_autosize.btf.XXXXXX"; int err, fd = -1, zero = 0; int char_id, short_id, int_id, long_long_id, void_ptr_id, id; + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, open_opts); struct test_core_autosize* skel = NULL; - struct bpf_object_load_attr load_attr = {}; struct bpf_program *prog; struct bpf_map *bss_map; struct btf *btf = NULL; @@ -125,9 +125,10 @@ void test_core_autosize(void) fd = -1; /* open and load BPF program with custom BTF as the kernel BTF */ - skel = test_core_autosize__open(); + open_opts.btf_custom_path = btf_file; + skel = test_core_autosize__open_opts(&open_opts); if (!ASSERT_OK_PTR(skel, "skel_open")) - return; + goto cleanup; /* disable handle_signed() for now */ prog = bpf_object__find_program_by_name(skel->obj, "handle_signed"); @@ -135,9 +136,7 @@ void test_core_autosize(void) goto cleanup; bpf_program__set_autoload(prog, false); - load_attr.obj = skel->obj; - load_attr.target_btf_path = btf_file; - err = bpf_object__load_xattr(&load_attr); + err = bpf_object__load(skel->obj); if (!ASSERT_OK(err, "prog_load")) goto cleanup; @@ -204,14 +203,13 @@ void test_core_autosize(void) skel = NULL; /* now re-load with handle_signed() enabled, it should fail loading */ - skel = test_core_autosize__open(); + open_opts.btf_custom_path = btf_file; + skel = test_core_autosize__open_opts(&open_opts); if (!ASSERT_OK_PTR(skel, "skel_open")) - return; + goto cleanup; - load_attr.obj = skel->obj; - load_attr.target_btf_path = btf_file; - err = bpf_object__load_xattr(&load_attr); - if (!ASSERT_ERR(err, "bad_prog_load")) + err = test_core_autosize__load(skel); + if (!ASSERT_ERR(err, "skel_load")) goto cleanup; cleanup: diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c index d02e064c535f..4739b15b2a97 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c +++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c @@ -816,7 +816,7 @@ static size_t roundup_page(size_t sz) void test_core_reloc(void) { const size_t mmap_sz = roundup_page(sizeof(struct data)); - struct bpf_object_load_attr load_attr = {}; + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, open_opts); struct core_reloc_test_case *test_case; const char *tp_name, *probe_name; int err, i, equal; @@ -846,9 +846,16 @@ void test_core_reloc(void) continue; } - obj = bpf_object__open_file(test_case->bpf_obj_file, NULL); + if (test_case->btf_src_file) { + err = access(test_case->btf_src_file, R_OK); + if (!ASSERT_OK(err, "btf_src_file")) + goto cleanup; + } + + open_opts.btf_custom_path = test_case->btf_src_file; + obj = bpf_object__open_file(test_case->bpf_obj_file, &open_opts); if (!ASSERT_OK_PTR(obj, "obj_open")) - continue; + goto cleanup; probe_name = "raw_tracepoint/sys_enter"; tp_name = "sys_enter"; @@ -862,17 +869,7 @@ void test_core_reloc(void) "prog '%s' not found\n", probe_name)) goto cleanup; - - if (test_case->btf_src_file) { - err = access(test_case->btf_src_file, R_OK); - if (!ASSERT_OK(err, "btf_src_file")) - goto cleanup; - } - - load_attr.obj = obj; - load_attr.log_level = 0; - load_attr.target_btf_path = test_case->btf_src_file; - err = bpf_object__load_xattr(&load_attr); + err = bpf_object__load(obj); if (err) { if (!test_case->fails) ASSERT_OK(err, "obj_load"); diff --git a/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c b/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c index 088b3653610d..02a465f36d59 100644 --- a/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c +++ b/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c @@ -17,6 +17,7 @@ void test_get_func_ip_test(void) */ #ifndef __x86_64__ bpf_program__set_autoload(skel->progs.test6, false); + bpf_program__set_autoload(skel->progs.test7, false); #endif err = get_func_ip_test__load(skel); @@ -46,6 +47,7 @@ void test_get_func_ip_test(void) ASSERT_EQ(skel->bss->test5_result, 1, "test5_result"); #ifdef __x86_64__ ASSERT_EQ(skel->bss->test6_result, 1, "test6_result"); + ASSERT_EQ(skel->bss->test7_result, 1, "test7_result"); #endif cleanup: diff --git a/tools/testing/selftests/bpf/prog_tests/pinning.c b/tools/testing/selftests/bpf/prog_tests/pinning.c index fcf54b3a1dd0..d4b953ae3407 100644 --- a/tools/testing/selftests/bpf/prog_tests/pinning.c +++ b/tools/testing/selftests/bpf/prog_tests/pinning.c @@ -125,6 +125,10 @@ void test_pinning(void) if (CHECK(err, "pin maps", "err %d errno %d\n", err, errno)) goto out; + /* get pinning path */ + if (!ASSERT_STREQ(bpf_map__pin_path(map), pinpath, "get pin path")) + goto out; + /* set pinning path of other map and re-pin all */ map = bpf_object__find_map_by_name(obj, "nopinmap"); if (CHECK(!map, "find map", "NULL map")) @@ -134,6 +138,11 @@ void test_pinning(void) if (CHECK(err, "set pin path", "err %d errno %d\n", err, errno)) goto out; + /* get pinning path after set */ + if (!ASSERT_STREQ(bpf_map__pin_path(map), custpinpath, + "get pin path after set")) + goto out; + /* should only pin the one unpinned map */ err = bpf_object__pin_maps(obj, NULL); if (CHECK(err, "pin maps", "err %d errno %d\n", err, errno)) diff --git a/tools/testing/selftests/bpf/prog_tests/tc_redirect.c b/tools/testing/selftests/bpf/prog_tests/tc_redirect.c index 5703c918812b..932e4ee3f97c 100644 --- a/tools/testing/selftests/bpf/prog_tests/tc_redirect.c +++ b/tools/testing/selftests/bpf/prog_tests/tc_redirect.c @@ -13,15 +13,16 @@ #define _GNU_SOURCE #include <arpa/inet.h> +#include <linux/if.h> +#include <linux/if_tun.h> #include <linux/limits.h> #include <linux/sysctl.h> -#include <linux/if_tun.h> -#include <linux/if.h> #include <sched.h> #include <stdbool.h> #include <stdio.h> -#include <sys/stat.h> #include <sys/mount.h> +#include <sys/stat.h> +#include <unistd.h> #include "test_progs.h" #include "network_helpers.h" @@ -389,11 +390,21 @@ done: close(client_fd); } -static int test_ping(int family, const char *addr) +static char *ping_command(int family) { - const char *ping = family == AF_INET6 ? "ping6" : "ping"; + if (family == AF_INET6) { + /* On some systems 'ping' doesn't support IPv6, so use ping6 if it is present. */ + if (!system("which ping6 >/dev/null 2>&1")) + return "ping6"; + else + return "ping -6"; + } + return "ping"; +} - SYS("ip netns exec " NS_SRC " %s " PING_ARGS " %s > /dev/null", ping, addr); +static int test_ping(int family, const char *addr) +{ + SYS("ip netns exec " NS_SRC " %s " PING_ARGS " %s > /dev/null", ping_command(family), addr); return 0; fail: return -1; diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_setsockopt.c b/tools/testing/selftests/bpf/progs/bpf_iter_setsockopt.c new file mode 100644 index 000000000000..b77adfd55d73 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_setsockopt.c @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ +#include "bpf_iter.h" +#include "bpf_tracing_net.h" +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_endian.h> + +#define bpf_tcp_sk(skc) ({ \ + struct sock_common *_skc = skc; \ + sk = NULL; \ + tp = NULL; \ + if (_skc) { \ + tp = bpf_skc_to_tcp_sock(_skc); \ + sk = (struct sock *)tp; \ + } \ + tp; \ +}) + +unsigned short reuse_listen_hport = 0; +unsigned short listen_hport = 0; +char cubic_cc[TCP_CA_NAME_MAX] = "bpf_cubic"; +char dctcp_cc[TCP_CA_NAME_MAX] = "bpf_dctcp"; +bool random_retry = false; + +static bool tcp_cc_eq(const char *a, const char *b) +{ + int i; + + for (i = 0; i < TCP_CA_NAME_MAX; i++) { + if (a[i] != b[i]) + return false; + if (!a[i]) + break; + } + + return true; +} + +SEC("iter/tcp") +int change_tcp_cc(struct bpf_iter__tcp *ctx) +{ + char cur_cc[TCP_CA_NAME_MAX]; + struct tcp_sock *tp; + struct sock *sk; + int ret; + + if (!bpf_tcp_sk(ctx->sk_common)) + return 0; + + if (sk->sk_family != AF_INET6 || + (sk->sk_state != TCP_LISTEN && + sk->sk_state != TCP_ESTABLISHED) || + (sk->sk_num != reuse_listen_hport && + sk->sk_num != listen_hport && + bpf_ntohs(sk->sk_dport) != listen_hport)) + return 0; + + if (bpf_getsockopt(tp, SOL_TCP, TCP_CONGESTION, + cur_cc, sizeof(cur_cc))) + return 0; + + if (!tcp_cc_eq(cur_cc, cubic_cc)) + return 0; + + if (random_retry && bpf_get_prandom_u32() % 4 == 1) + return 1; + + bpf_setsockopt(tp, SOL_TCP, TCP_CONGESTION, dctcp_cc, sizeof(dctcp_cc)); + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h index 01378911252b..3af0998a0623 100644 --- a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h +++ b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h @@ -5,6 +5,10 @@ #define AF_INET 2 #define AF_INET6 10 +#define SOL_TCP 6 +#define TCP_CONGESTION 13 +#define TCP_CA_NAME_MAX 16 + #define ICSK_TIME_RETRANS 1 #define ICSK_TIME_PROBE0 3 #define ICSK_TIME_LOSS_PROBE 5 @@ -32,6 +36,8 @@ #define ir_v6_rmt_addr req.__req_common.skc_v6_daddr #define ir_v6_loc_addr req.__req_common.skc_v6_rcv_saddr +#define sk_num __sk_common.skc_num +#define sk_dport __sk_common.skc_dport #define sk_family __sk_common.skc_family #define sk_rmem_alloc sk_backlog.rmem_alloc #define sk_refcnt __sk_common.skc_refcnt diff --git a/tools/testing/selftests/bpf/progs/get_func_ip_test.c b/tools/testing/selftests/bpf/progs/get_func_ip_test.c index acd587b6e859..a587aeca5ae0 100644 --- a/tools/testing/selftests/bpf/progs/get_func_ip_test.c +++ b/tools/testing/selftests/bpf/progs/get_func_ip_test.c @@ -11,6 +11,7 @@ extern const void bpf_fentry_test3 __ksym; extern const void bpf_fentry_test4 __ksym; extern const void bpf_modify_return_test __ksym; extern const void bpf_fentry_test6 __ksym; +extern const void bpf_fentry_test7 __ksym; __u64 test1_result = 0; SEC("fentry/bpf_fentry_test1") @@ -71,3 +72,13 @@ int test6(struct pt_regs *ctx) test6_result = (const void *) addr == &bpf_fentry_test6 + 5; return 0; } + +__u64 test7_result = 0; +SEC("kprobe/bpf_fentry_test7+5") +int test7(struct pt_regs *ctx) +{ + __u64 addr = bpf_get_func_ip(ctx); + + test7_result = (const void *) addr == &bpf_fentry_test7 + 5; + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/netcnt_prog.c b/tools/testing/selftests/bpf/progs/netcnt_prog.c index d071adf178bd..43649bce4c54 100644 --- a/tools/testing/selftests/bpf/progs/netcnt_prog.c +++ b/tools/testing/selftests/bpf/progs/netcnt_prog.c @@ -13,21 +13,21 @@ struct { __uint(type, BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE); __type(key, struct bpf_cgroup_storage_key); - __type(value, struct percpu_net_cnt); + __type(value, union percpu_net_cnt); } percpu_netcnt SEC(".maps"); struct { __uint(type, BPF_MAP_TYPE_CGROUP_STORAGE); __type(key, struct bpf_cgroup_storage_key); - __type(value, struct net_cnt); + __type(value, union net_cnt); } netcnt SEC(".maps"); SEC("cgroup/skb") int bpf_nextcnt(struct __sk_buff *skb) { - struct percpu_net_cnt *percpu_cnt; + union percpu_net_cnt *percpu_cnt; char fmt[] = "%d %llu %llu\n"; - struct net_cnt *cnt; + union net_cnt *cnt; __u64 ts, dt; int ret; diff --git a/tools/testing/selftests/bpf/progs/test_map_in_map_invalid.c b/tools/testing/selftests/bpf/progs/test_map_in_map_invalid.c new file mode 100644 index 000000000000..703c08e06442 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_map_in_map_invalid.c @@ -0,0 +1,26 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Isovalent, Inc. */ +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct inner { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, __u32); + __type(value, int); + __uint(max_entries, 4); +}; + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); + __uint(max_entries, 0); /* This will make map creation to fail */ + __uint(key_size, sizeof(__u32)); + __array(values, struct inner); +} mim SEC(".maps"); + +SEC("xdp") +int xdp_noop0(struct xdp_md *ctx) +{ + return XDP_PASS; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/test_bpftool_synctypes.py b/tools/testing/selftests/bpf/test_bpftool_synctypes.py new file mode 100755 index 000000000000..be54b7335a76 --- /dev/null +++ b/tools/testing/selftests/bpf/test_bpftool_synctypes.py @@ -0,0 +1,586 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +# +# Copyright (C) 2021 Isovalent, Inc. + +import argparse +import re +import os, sys + +LINUX_ROOT = os.path.abspath(os.path.join(__file__, + os.pardir, os.pardir, os.pardir, os.pardir, os.pardir)) +BPFTOOL_DIR = os.path.join(LINUX_ROOT, 'tools/bpf/bpftool') +retval = 0 + +class BlockParser(object): + """ + A parser for extracting set of values from blocks such as enums. + @reader: a pointer to the open file to parse + """ + def __init__(self, reader): + self.reader = reader + + def search_block(self, start_marker): + """ + Search for a given structure in a file. + @start_marker: regex marking the beginning of a structure to parse + """ + offset = self.reader.tell() + array_start = re.search(start_marker, self.reader.read()) + if array_start is None: + raise Exception('Failed to find start of block') + self.reader.seek(offset + array_start.start()) + + def parse(self, pattern, end_marker): + """ + Parse a block and return a set of values. Values to extract must be + on separate lines in the file. + @pattern: pattern used to identify the values to extract + @end_marker: regex marking the end of the block to parse + """ + entries = set() + while True: + line = self.reader.readline() + if not line or re.match(end_marker, line): + break + capture = pattern.search(line) + if capture and pattern.groups >= 1: + entries.add(capture.group(1)) + return entries + +class ArrayParser(BlockParser): + """ + A parser for extracting dicionaries of values from some BPF-related arrays. + @reader: a pointer to the open file to parse + @array_name: name of the array to parse + """ + end_marker = re.compile('^};') + + def __init__(self, reader, array_name): + self.array_name = array_name + self.start_marker = re.compile(f'(static )?const char \* const {self.array_name}\[.*\] = {{\n') + super().__init__(reader) + + def search_block(self): + """ + Search for the given array in a file. + """ + super().search_block(self.start_marker); + + def parse(self): + """ + Parse a block and return data as a dictionary. Items to extract must be + on separate lines in the file. + """ + pattern = re.compile('\[(BPF_\w*)\]\s*= "(.*)",?$') + entries = {} + while True: + line = self.reader.readline() + if line == '' or re.match(self.end_marker, line): + break + capture = pattern.search(line) + if capture: + entries[capture.group(1)] = capture.group(2) + return entries + +class InlineListParser(BlockParser): + """ + A parser for extracting set of values from inline lists. + """ + def parse(self, pattern, end_marker): + """ + Parse a block and return a set of values. Multiple values to extract + can be on a same line in the file. + @pattern: pattern used to identify the values to extract + @end_marker: regex marking the end of the block to parse + """ + entries = set() + while True: + line = self.reader.readline() + if not line: + break + entries.update(pattern.findall(line)) + if re.search(end_marker, line): + break + return entries + +class FileExtractor(object): + """ + A generic reader for extracting data from a given file. This class contains + several helper methods that wrap arround parser objects to extract values + from different structures. + This class does not offer a way to set a filename, which is expected to be + defined in children classes. + """ + def __init__(self): + self.reader = open(self.filename, 'r') + + def close(self): + """ + Close the file used by the parser. + """ + self.reader.close() + + def reset_read(self): + """ + Reset the file position indicator for this parser. This is useful when + parsing several structures in the file without respecting the order in + which those structures appear in the file. + """ + self.reader.seek(0) + + def get_types_from_array(self, array_name): + """ + Search for and parse an array associating names to BPF_* enum members, + for example: + + const char * const prog_type_name[] = { + [BPF_PROG_TYPE_UNSPEC] = "unspec", + [BPF_PROG_TYPE_SOCKET_FILTER] = "socket_filter", + [BPF_PROG_TYPE_KPROBE] = "kprobe", + }; + + Return a dictionary with the enum member names as keys and the + associated names as values, for example: + + {'BPF_PROG_TYPE_UNSPEC': 'unspec', + 'BPF_PROG_TYPE_SOCKET_FILTER': 'socket_filter', + 'BPF_PROG_TYPE_KPROBE': 'kprobe'} + + @array_name: name of the array to parse + """ + array_parser = ArrayParser(self.reader, array_name) + array_parser.search_block() + return array_parser.parse() + + def get_enum(self, enum_name): + """ + Search for and parse an enum containing BPF_* members, for example: + + enum bpf_prog_type { + BPF_PROG_TYPE_UNSPEC, + BPF_PROG_TYPE_SOCKET_FILTER, + BPF_PROG_TYPE_KPROBE, + }; + + Return a set containing all member names, for example: + + {'BPF_PROG_TYPE_UNSPEC', + 'BPF_PROG_TYPE_SOCKET_FILTER', + 'BPF_PROG_TYPE_KPROBE'} + + @enum_name: name of the enum to parse + """ + start_marker = re.compile(f'enum {enum_name} {{\n') + pattern = re.compile('^\s*(BPF_\w+),?$') + end_marker = re.compile('^};') + parser = BlockParser(self.reader) + parser.search_block(start_marker) + return parser.parse(pattern, end_marker) + + def __get_description_list(self, start_marker, pattern, end_marker): + parser = InlineListParser(self.reader) + parser.search_block(start_marker) + return parser.parse(pattern, end_marker) + + def get_rst_list(self, block_name): + """ + Search for and parse a list of type names from RST documentation, for + example: + + | *TYPE* := { + | **socket** | **kprobe** | + | **kretprobe** + | } + + Return a set containing all type names, for example: + + {'socket', 'kprobe', 'kretprobe'} + + @block_name: name of the blog to parse, 'TYPE' in the example + """ + start_marker = re.compile(f'\*{block_name}\* := {{') + pattern = re.compile('\*\*([\w/-]+)\*\*') + end_marker = re.compile('}\n') + return self.__get_description_list(start_marker, pattern, end_marker) + + def get_help_list(self, block_name): + """ + Search for and parse a list of type names from a help message in + bpftool, for example: + + " TYPE := { socket | kprobe |\\n" + " kretprobe }\\n" + + Return a set containing all type names, for example: + + {'socket', 'kprobe', 'kretprobe'} + + @block_name: name of the blog to parse, 'TYPE' in the example + """ + start_marker = re.compile(f'"\s*{block_name} := {{') + pattern = re.compile('([\w/]+) [|}]') + end_marker = re.compile('}') + return self.__get_description_list(start_marker, pattern, end_marker) + + def get_help_list_macro(self, macro): + """ + Search for and parse a list of values from a help message starting with + a macro in bpftool, for example: + + " " HELP_SPEC_OPTIONS " |\\n" + " {-f|--bpffs} | {-m|--mapcompat} | {-n|--nomount} }\\n" + + Return a set containing all item names, for example: + + {'-f', '--bpffs', '-m', '--mapcompat', '-n', '--nomount'} + + @macro: macro starting the block, 'HELP_SPEC_OPTIONS' in the example + """ + start_marker = re.compile(f'"\s*{macro}\s*" [|}}]') + pattern = re.compile('([\w-]+) ?(?:\||}[ }\]])') + end_marker = re.compile('}\\\\n') + return self.__get_description_list(start_marker, pattern, end_marker) + + def default_options(self): + """ + Return the default options contained in HELP_SPEC_OPTIONS + """ + return { '-j', '--json', '-p', '--pretty', '-d', '--debug' } + + def get_bashcomp_list(self, block_name): + """ + Search for and parse a list of type names from a variable in bash + completion file, for example: + + local BPFTOOL_PROG_LOAD_TYPES='socket kprobe \\ + kretprobe' + + Return a set containing all type names, for example: + + {'socket', 'kprobe', 'kretprobe'} + + @block_name: name of the blog to parse, 'TYPE' in the example + """ + start_marker = re.compile(f'local {block_name}=\'') + pattern = re.compile('(?:.*=\')?([\w/]+)') + end_marker = re.compile('\'$') + return self.__get_description_list(start_marker, pattern, end_marker) + +class SourceFileExtractor(FileExtractor): + """ + An abstract extractor for a source file with usage message. + This class does not offer a way to set a filename, which is expected to be + defined in children classes. + """ + def get_options(self): + return self.default_options().union(self.get_help_list_macro('HELP_SPEC_OPTIONS')) + +class ProgFileExtractor(SourceFileExtractor): + """ + An extractor for bpftool's prog.c. + """ + filename = os.path.join(BPFTOOL_DIR, 'prog.c') + + def get_prog_types(self): + return self.get_types_from_array('prog_type_name') + + def get_attach_types(self): + return self.get_types_from_array('attach_type_strings') + + def get_prog_attach_help(self): + return self.get_help_list('ATTACH_TYPE') + +class MapFileExtractor(SourceFileExtractor): + """ + An extractor for bpftool's map.c. + """ + filename = os.path.join(BPFTOOL_DIR, 'map.c') + + def get_map_types(self): + return self.get_types_from_array('map_type_name') + + def get_map_help(self): + return self.get_help_list('TYPE') + +class CgroupFileExtractor(SourceFileExtractor): + """ + An extractor for bpftool's cgroup.c. + """ + filename = os.path.join(BPFTOOL_DIR, 'cgroup.c') + + def get_prog_attach_help(self): + return self.get_help_list('ATTACH_TYPE') + +class CommonFileExtractor(SourceFileExtractor): + """ + An extractor for bpftool's common.c. + """ + filename = os.path.join(BPFTOOL_DIR, 'common.c') + + def __init__(self): + super().__init__() + self.attach_types = {} + + def get_attach_types(self): + if not self.attach_types: + self.attach_types = self.get_types_from_array('attach_type_name') + return self.attach_types + + def get_cgroup_attach_types(self): + if not self.attach_types: + self.get_attach_types() + cgroup_types = {} + for (key, value) in self.attach_types.items(): + if key.find('BPF_CGROUP') != -1: + cgroup_types[key] = value + return cgroup_types + +class GenericSourceExtractor(SourceFileExtractor): + """ + An extractor for generic source code files. + """ + filename = "" + + def __init__(self, filename): + self.filename = os.path.join(BPFTOOL_DIR, filename) + super().__init__() + +class BpfHeaderExtractor(FileExtractor): + """ + An extractor for the UAPI BPF header. + """ + filename = os.path.join(LINUX_ROOT, 'tools/include/uapi/linux/bpf.h') + + def get_prog_types(self): + return self.get_enum('bpf_prog_type') + + def get_map_types(self): + return self.get_enum('bpf_map_type') + + def get_attach_types(self): + return self.get_enum('bpf_attach_type') + +class ManPageExtractor(FileExtractor): + """ + An abstract extractor for an RST documentation page. + This class does not offer a way to set a filename, which is expected to be + defined in children classes. + """ + def get_options(self): + return self.get_rst_list('OPTIONS') + +class ManProgExtractor(ManPageExtractor): + """ + An extractor for bpftool-prog.rst. + """ + filename = os.path.join(BPFTOOL_DIR, 'Documentation/bpftool-prog.rst') + + def get_attach_types(self): + return self.get_rst_list('ATTACH_TYPE') + +class ManMapExtractor(ManPageExtractor): + """ + An extractor for bpftool-map.rst. + """ + filename = os.path.join(BPFTOOL_DIR, 'Documentation/bpftool-map.rst') + + def get_map_types(self): + return self.get_rst_list('TYPE') + +class ManCgroupExtractor(ManPageExtractor): + """ + An extractor for bpftool-cgroup.rst. + """ + filename = os.path.join(BPFTOOL_DIR, 'Documentation/bpftool-cgroup.rst') + + def get_attach_types(self): + return self.get_rst_list('ATTACH_TYPE') + +class ManGenericExtractor(ManPageExtractor): + """ + An extractor for generic RST documentation pages. + """ + filename = "" + + def __init__(self, filename): + self.filename = os.path.join(BPFTOOL_DIR, filename) + super().__init__() + +class BashcompExtractor(FileExtractor): + """ + An extractor for bpftool's bash completion file. + """ + filename = os.path.join(BPFTOOL_DIR, 'bash-completion/bpftool') + + def get_prog_attach_types(self): + return self.get_bashcomp_list('BPFTOOL_PROG_ATTACH_TYPES') + + def get_map_types(self): + return self.get_bashcomp_list('BPFTOOL_MAP_CREATE_TYPES') + + def get_cgroup_attach_types(self): + return self.get_bashcomp_list('BPFTOOL_CGROUP_ATTACH_TYPES') + +def verify(first_set, second_set, message): + """ + Print all values that differ between two sets. + @first_set: one set to compare + @second_set: another set to compare + @message: message to print for values belonging to only one of the sets + """ + global retval + diff = first_set.symmetric_difference(second_set) + if diff: + print(message, diff) + retval = 1 + +def main(): + # No arguments supported at this time, but print usage for -h|--help + argParser = argparse.ArgumentParser(description=""" + Verify that bpftool's code, help messages, documentation and bash + completion are all in sync on program types, map types, attach types, and + options. Also check that bpftool is in sync with the UAPI BPF header. + """) + args = argParser.parse_args() + + # Map types (enum) + + bpf_info = BpfHeaderExtractor() + ref = bpf_info.get_map_types() + + map_info = MapFileExtractor() + source_map_items = map_info.get_map_types() + map_types_enum = set(source_map_items.keys()) + + verify(ref, map_types_enum, + f'Comparing BPF header (enum bpf_map_type) and {MapFileExtractor.filename} (map_type_name):') + + # Map types (names) + + source_map_types = set(source_map_items.values()) + source_map_types.discard('unspec') + + help_map_types = map_info.get_map_help() + help_map_options = map_info.get_options() + map_info.close() + + man_map_info = ManMapExtractor() + man_map_options = man_map_info.get_options() + man_map_types = man_map_info.get_map_types() + man_map_info.close() + + bashcomp_info = BashcompExtractor() + bashcomp_map_types = bashcomp_info.get_map_types() + + verify(source_map_types, help_map_types, + f'Comparing {MapFileExtractor.filename} (map_type_name) and {MapFileExtractor.filename} (do_help() TYPE):') + verify(source_map_types, man_map_types, + f'Comparing {MapFileExtractor.filename} (map_type_name) and {ManMapExtractor.filename} (TYPE):') + verify(help_map_options, man_map_options, + f'Comparing {MapFileExtractor.filename} (do_help() OPTIONS) and {ManMapExtractor.filename} (OPTIONS):') + verify(source_map_types, bashcomp_map_types, + f'Comparing {MapFileExtractor.filename} (map_type_name) and {BashcompExtractor.filename} (BPFTOOL_MAP_CREATE_TYPES):') + + # Program types (enum) + + ref = bpf_info.get_prog_types() + + prog_info = ProgFileExtractor() + prog_types = set(prog_info.get_prog_types().keys()) + + verify(ref, prog_types, + f'Comparing BPF header (enum bpf_prog_type) and {ProgFileExtractor.filename} (prog_type_name):') + + # Attach types (enum) + + ref = bpf_info.get_attach_types() + bpf_info.close() + + common_info = CommonFileExtractor() + attach_types = common_info.get_attach_types() + + verify(ref, attach_types, + f'Comparing BPF header (enum bpf_attach_type) and {CommonFileExtractor.filename} (attach_type_name):') + + # Attach types (names) + + source_prog_attach_types = set(prog_info.get_attach_types().values()) + + help_prog_attach_types = prog_info.get_prog_attach_help() + help_prog_options = prog_info.get_options() + prog_info.close() + + man_prog_info = ManProgExtractor() + man_prog_options = man_prog_info.get_options() + man_prog_attach_types = man_prog_info.get_attach_types() + man_prog_info.close() + + bashcomp_info.reset_read() # We stopped at map types, rewind + bashcomp_prog_attach_types = bashcomp_info.get_prog_attach_types() + + verify(source_prog_attach_types, help_prog_attach_types, + f'Comparing {ProgFileExtractor.filename} (attach_type_strings) and {ProgFileExtractor.filename} (do_help() ATTACH_TYPE):') + verify(source_prog_attach_types, man_prog_attach_types, + f'Comparing {ProgFileExtractor.filename} (attach_type_strings) and {ManProgExtractor.filename} (ATTACH_TYPE):') + verify(help_prog_options, man_prog_options, + f'Comparing {ProgFileExtractor.filename} (do_help() OPTIONS) and {ManProgExtractor.filename} (OPTIONS):') + verify(source_prog_attach_types, bashcomp_prog_attach_types, + f'Comparing {ProgFileExtractor.filename} (attach_type_strings) and {BashcompExtractor.filename} (BPFTOOL_PROG_ATTACH_TYPES):') + + # Cgroup attach types + + source_cgroup_attach_types = set(common_info.get_cgroup_attach_types().values()) + common_info.close() + + cgroup_info = CgroupFileExtractor() + help_cgroup_attach_types = cgroup_info.get_prog_attach_help() + help_cgroup_options = cgroup_info.get_options() + cgroup_info.close() + + man_cgroup_info = ManCgroupExtractor() + man_cgroup_options = man_cgroup_info.get_options() + man_cgroup_attach_types = man_cgroup_info.get_attach_types() + man_cgroup_info.close() + + bashcomp_cgroup_attach_types = bashcomp_info.get_cgroup_attach_types() + bashcomp_info.close() + + verify(source_cgroup_attach_types, help_cgroup_attach_types, + f'Comparing {CommonFileExtractor.filename} (attach_type_strings) and {CgroupFileExtractor.filename} (do_help() ATTACH_TYPE):') + verify(source_cgroup_attach_types, man_cgroup_attach_types, + f'Comparing {CommonFileExtractor.filename} (attach_type_strings) and {ManCgroupExtractor.filename} (ATTACH_TYPE):') + verify(help_cgroup_options, man_cgroup_options, + f'Comparing {CgroupFileExtractor.filename} (do_help() OPTIONS) and {ManCgroupExtractor.filename} (OPTIONS):') + verify(source_cgroup_attach_types, bashcomp_cgroup_attach_types, + f'Comparing {CommonFileExtractor.filename} (attach_type_strings) and {BashcompExtractor.filename} (BPFTOOL_CGROUP_ATTACH_TYPES):') + + # Options for remaining commands + + for cmd in [ 'btf', 'feature', 'gen', 'iter', 'link', 'net', 'perf', 'struct_ops', ]: + source_info = GenericSourceExtractor(cmd + '.c') + help_cmd_options = source_info.get_options() + source_info.close() + + man_cmd_info = ManGenericExtractor(os.path.join('Documentation', 'bpftool-' + cmd + '.rst')) + man_cmd_options = man_cmd_info.get_options() + man_cmd_info.close() + + verify(help_cmd_options, man_cmd_options, + f'Comparing {source_info.filename} (do_help() OPTIONS) and {man_cmd_info.filename} (OPTIONS):') + + source_main_info = GenericSourceExtractor('main.c') + help_main_options = source_main_info.get_options() + source_main_info.close() + + man_main_info = ManGenericExtractor(os.path.join('Documentation', 'bpftool.rst')) + man_main_options = man_main_info.get_options() + man_main_info.close() + + verify(help_main_options, man_main_options, + f'Comparing {source_main_info.filename} (do_help() OPTIONS) and {man_main_info.filename} (OPTIONS):') + + sys.exit(retval) + +if __name__ == "__main__": + main() diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index 30cbf5d98f7d..14cea869235b 100644 --- a/tools/testing/selftests/bpf/test_maps.c +++ b/tools/testing/selftests/bpf/test_maps.c @@ -764,8 +764,8 @@ static void test_sockmap(unsigned int tasks, void *data) udp = socket(AF_INET, SOCK_DGRAM, 0); i = 0; err = bpf_map_update_elem(fd, &i, &udp, BPF_ANY); - if (!err) { - printf("Failed socket SOCK_DGRAM allowed '%i:%i'\n", + if (err) { + printf("Failed socket update SOCK_DGRAM '%i:%i'\n", i, udp); goto out_sockmap; } @@ -1153,12 +1153,17 @@ out_sockmap: } #define MAPINMAP_PROG "./test_map_in_map.o" +#define MAPINMAP_INVALID_PROG "./test_map_in_map_invalid.o" static void test_map_in_map(void) { struct bpf_object *obj; struct bpf_map *map; int mim_fd, fd, err; int pos = 0; + struct bpf_map_info info = {}; + __u32 len = sizeof(info); + __u32 id = 0; + libbpf_print_fn_t old_print_fn; obj = bpf_object__open(MAPINMAP_PROG); @@ -1228,11 +1233,72 @@ static void test_map_in_map(void) } close(fd); + fd = -1; bpf_object__close(obj); + + /* Test that failing bpf_object__create_map() destroys the inner map */ + obj = bpf_object__open(MAPINMAP_INVALID_PROG); + err = libbpf_get_error(obj); + if (err) { + printf("Failed to load %s program: %d %d", + MAPINMAP_INVALID_PROG, err, errno); + goto out_map_in_map; + } + + map = bpf_object__find_map_by_name(obj, "mim"); + if (!map) { + printf("Failed to load array of maps from test prog\n"); + goto out_map_in_map; + } + + old_print_fn = libbpf_set_print(NULL); + + err = bpf_object__load(obj); + if (!err) { + printf("Loading obj supposed to fail\n"); + goto out_map_in_map; + } + + libbpf_set_print(old_print_fn); + + /* Iterate over all maps to check whether the internal map + * ("mim.internal") has been destroyed. + */ + while (true) { + err = bpf_map_get_next_id(id, &id); + if (err) { + if (errno == ENOENT) + break; + printf("Failed to get next map: %d", errno); + goto out_map_in_map; + } + + fd = bpf_map_get_fd_by_id(id); + if (fd < 0) { + if (errno == ENOENT) + continue; + printf("Failed to get map by id %u: %d", id, errno); + goto out_map_in_map; + } + + err = bpf_obj_get_info_by_fd(fd, &info, &len); + if (err) { + printf("Failed to get map info by fd %d: %d", fd, + errno); + goto out_map_in_map; + } + + if (!strcmp(info.name, "mim.inner")) { + printf("Inner map mim.inner was not destroyed\n"); + goto out_map_in_map; + } + } + return; out_map_in_map: - close(fd); + if (fd >= 0) + close(fd); exit(1); } diff --git a/tools/testing/selftests/bpf/test_netcnt.c b/tools/testing/selftests/bpf/test_netcnt.c index a7b9a69f4fd5..4990a99e7381 100644 --- a/tools/testing/selftests/bpf/test_netcnt.c +++ b/tools/testing/selftests/bpf/test_netcnt.c @@ -33,14 +33,14 @@ static int bpf_find_map(const char *test, struct bpf_object *obj, int main(int argc, char **argv) { - struct percpu_net_cnt *percpu_netcnt; + union percpu_net_cnt *percpu_netcnt; struct bpf_cgroup_storage_key key; int map_fd, percpu_map_fd; int error = EXIT_FAILURE; - struct net_cnt netcnt; struct bpf_object *obj; int prog_fd, cgroup_fd; unsigned long packets; + union net_cnt netcnt; unsigned long bytes; int cpu, nproc; __u32 prog_cnt; diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h index 8ef7f334e715..c8c2bf878f67 100644 --- a/tools/testing/selftests/bpf/test_progs.h +++ b/tools/testing/selftests/bpf/test_progs.h @@ -221,6 +221,18 @@ extern int test__join_cgroup(const char *path); ___ok; \ }) +#define ASSERT_STRNEQ(actual, expected, len, name) ({ \ + static int duration = 0; \ + const char *___act = actual; \ + const char *___exp = expected; \ + int ___len = len; \ + bool ___ok = strncmp(___act, ___exp, ___len) == 0; \ + CHECK(!___ok, (name), \ + "unexpected %s: actual '%.*s' != expected '%.*s'\n", \ + (name), ___len, ___act, ___len, ___exp); \ + ___ok; \ +}) + #define ASSERT_OK(res, name) ({ \ static int duration = 0; \ long long ___res = (res); \ diff --git a/tools/testing/selftests/bpf/test_tc_tunnel.sh b/tools/testing/selftests/bpf/test_tc_tunnel.sh index c9dde9b9d987..088fcad138c9 100755 --- a/tools/testing/selftests/bpf/test_tc_tunnel.sh +++ b/tools/testing/selftests/bpf/test_tc_tunnel.sh @@ -69,7 +69,7 @@ cleanup() { } server_listen() { - ip netns exec "${ns2}" nc "${netcat_opt}" -l -p "${port}" > "${outfile}" & + ip netns exec "${ns2}" nc "${netcat_opt}" -l "${port}" > "${outfile}" & server_pid=$! sleep 0.2 } |