linux-dev/tools/bpf, branch master

bpftool: Fix NULL pointer dereference when pin {PROG, MAP, LINK} without FILE

2022-11-02T11:05:42Z

When using bpftool to pin {PROG, MAP, LINK} without FILE, segmentation fault will occur. The reson is that the lack of FILE will cause strlen to trigger NULL pointer dereference. The corresponding stacktrace is shown below: do_pin do_pin_any do_pin_fd mount_bpffs_for_pin strlen(name) <- NULL pointer dereference Fix it by adding validation to the common process. Fixes: 75a1e792c335 ("tools: bpftool: Allow all prog/map handles for pinning objects") Signed-off-by: Pu Lehui Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20221102084034.3342995-1-pulehui@huaweicloud.com

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2022-10-04T00:44:18Z

Merge in the left-over fixes before the net-next pull-request. Conflicts: drivers/net/ethernet/mediatek/mtk_ppe.c ae3ed15da588 ("net: ethernet: mtk_eth_soc: fix state in __mtk_foe_entry_clear") 9d8cb4c096ab ("net: ethernet: mtk_eth_soc: add foe_entry_size to mtk_eth_soc") https://lore.kernel.org/all/6cb6893b-4921-a068-4c30-1109795110bb@tessares.net/ kernel/bpf/helpers.c 8addbfc7b308 ("bpf: Gate dynptr API behind CAP_BPF") 5679ff2f138f ("bpf: Move bpf_loop and bpf_for_each_map_elem under CAP_BPF") 8a67f2de9b1d ("bpf: expose bpf_strtol and bpf_strtoul to all program types") https://lore.kernel.org/all/20221003201957.13149-1-daniel@iogearbox.net/ Signed-off-by: Jakub Kicinski

bpftool: Fix error message of strerror

2022-09-30T22:40:46Z

strerror() expects a positive errno, however variable err will never be positive when an error occurs. This causes bpftool to output too many "unknown error", even a simple "file not exist" error can not get an accurate message. This patch fixed all "strerror(err)" patterns in bpftool. Specially in btf.c#L823, hashmap__append() is an internal function of libbpf and will not change errno, so there's a little difference. Some libbpf_get_error() calls are kept for return values. Changes since v1: https://lore.kernel.org/bpf/SY4P282MB1084B61CD8671DFA395AA8579D539@SY4P282MB1084.AUSP282.PROD.OUTLOOK.COM/ Check directly for NULL values instead of calling libbpf_get_error(). Signed-off-by: Tianyi Liu Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/SY4P282MB1084AD9CD84A920F08DF83E29D549@SY4P282MB1084.AUSP282.PROD.OUTLOOK.COM

bpftool: Remove unused struct event_ring_info

2022-09-30T21:09:05Z

After commit 9b190f185d2f ("tools/bpftool: switch map event_pipe to libbpf's perf_buffer"), struct event_ring_info is not used any more and can be removed as well. Signed-off-by: Yuan Can Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220928090440.79637-3-yuancan@huawei.com

bpftool: Remove unused struct btf_attach_point

2022-09-30T21:08:40Z

After commit 2828d0d75b73 ("bpftool: Switch to libbpf's hashmap for programs/maps in BTF listing"), struct btf_attach_point is not used anymore and can be removed as well. Signed-off-by: Yuan Can Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220928090440.79637-2-yuancan@huawei.com

bpftool: Show parameters of BPF task iterators.

2022-09-28T23:30:08Z

Show tid or pid of iterators if giving an argument of tid or pid For example, the command `bpftool link list` may list following lines. 1: iter prog 2 target_name bpf_map 2: iter prog 3 target_name bpf_prog 33: iter prog 225 target_name task_file tid 1644 pids test_progs(1644) Link 33 is a task_file iterator with tid 1644. For now, only targets of task, task_file and task_vma may be with tid or pid to filter out tasks other than those belonging to a process (pid) or a thread (tid). Signed-off-by: Kui-Feng Lee Signed-off-by: Andrii Nakryiko Acked-by: Quentin Monnet Acked-by: Yonghong Song Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20220926184957.208194-6-kuifeng@fb.com

bpf: Define new BPF_MAP_TYPE_USER_RINGBUF map type

2022-09-21T23:24:17Z

We want to support a ringbuf map type where samples are published from user-space, to be consumed by BPF programs. BPF currently supports a kernel -> user-space circular ring buffer via the BPF_MAP_TYPE_RINGBUF map type. We'll need to define a new map type for user-space -> kernel, as none of the helpers exported for BPF_MAP_TYPE_RINGBUF will apply to a user-space producer ring buffer, and we'll want to add one or more helper functions that would not apply for a kernel-producer ring buffer. This patch therefore adds a new BPF_MAP_TYPE_USER_RINGBUF map type definition. The map type is useless in its current form, as there is no way to access or use it for anything until we one or more BPF helpers. A follow-on patch will therefore add a new helper function that allows BPF programs to run callbacks on samples that are published to the ring buffer. Signed-off-by: David Vernet Signed-off-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220920000100.477320-2-void@manifault.com

bpftool: Fix wrong cgroup attach flags being assigned to effective progs

2022-09-21T17:57:12Z

When root-cgroup attach multi progs and sub-cgroup attach a override prog, bpftool will display incorrectly for the attach flags of the sub-cgroup’s effective progs: $ bpftool cgroup tree /sys/fs/cgroup effective CgroupPath ID AttachType AttachFlags Name /sys/fs/cgroup 6 cgroup_sysctl multi sysctl_tcp_mem 13 cgroup_sysctl multi sysctl_tcp_mem /sys/fs/cgroup/cg1 20 cgroup_sysctl override sysctl_tcp_mem 6 cgroup_sysctl override sysctl_tcp_mem <- wrong 13 cgroup_sysctl override sysctl_tcp_mem <- wrong /sys/fs/cgroup/cg1/cg2 20 cgroup_sysctl sysctl_tcp_mem 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem Attach flags is only valid for attached progs of this layer cgroup, but not for effective progs. For querying with EFFECTIVE flags, exporting attach flags does not make sense. So let's remove the AttachFlags field and the associated logic. After this patch, the above effective cgroup tree will show as bellow: $ bpftool cgroup tree /sys/fs/cgroup effective CgroupPath ID AttachType Name /sys/fs/cgroup 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem /sys/fs/cgroup/cg1 20 cgroup_sysctl sysctl_tcp_mem 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem /sys/fs/cgroup/cg1/cg2 20 cgroup_sysctl sysctl_tcp_mem 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem Fixes: b79c9fc9551b ("bpf: implement BPF_PROG_QUERY for BPF_LSM_CGROUP") Fixes: a98bf57391a2 ("tools: bpftool: add support for reporting the effective cgroup progs") Signed-off-by: Pu Lehui Link: https://lore.kernel.org/r/20220921104604.2340580-3-pulehui@huaweicloud.com Signed-off-by: Martin KaFai Lau

Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2022-09-06T21:21:18Z

Daniel Borkmann says: ==================== pull-request: bpf-next 2022-09-05 The following pull-request contains BPF updates for your *net-next* tree. We've added 106 non-merge commits during the last 18 day(s) which contain a total of 159 files changed, 5225 insertions(+), 1358 deletions(-). There are two small merge conflicts, resolve them as follows: 1) tools/testing/selftests/bpf/DENYLIST.s390x Commit 27e23836ce22 ("selftests/bpf: Add lru_bug to s390x deny list") in bpf tree was needed to get BPF CI green on s390x, but it conflicted with newly added tests on bpf-next. Resolve by adding both hunks, result: [...] lru_bug # prog 'printk': failed to auto-attach: -524 setget_sockopt # attach unexpected error: -524 (trampoline) cb_refs # expected error message unexpected error: -524 (trampoline) cgroup_hierarchical_stats # JIT does not support calling kernel function (kfunc) htab_update # failed to attach: ERROR: strerror_r(-524)=22 (trampoline) [...] 2) net/core/filter.c Commit 1227c1771dd2 ("net: Fix data-races around sysctl_[rw]mem_(max|default).") from net tree conflicts with commit 29003875bd5b ("bpf: Change bpf_setsockopt(SOL_SOCKET) to reuse sk_setsockopt()") from bpf-next tree. Take the code as it is from bpf-next tree, result: [...] if (getopt) { if (optname == SO_BINDTODEVICE) return -EINVAL; return sk_getsockopt(sk, SOL_SOCKET, optname, KERNEL_SOCKPTR(optval), KERNEL_SOCKPTR(optlen)); } return sk_setsockopt(sk, SOL_SOCKET, optname, KERNEL_SOCKPTR(optval), *optlen); [...] The main changes are: 1) Add any-context BPF specific memory allocator which is useful in particular for BPF tracing with bonus of performance equal to full prealloc, from Alexei Starovoitov. 2) Big batch to remove duplicated code from bpf_{get,set}sockopt() helpers as an effort to reuse the existing core socket code as much as possible, from Martin KaFai Lau. 3) Extend BPF flow dissector for BPF programs to just augment the in-kernel dissector with custom logic. In other words, allow for partial replacement, from Shmulik Ladkani. 4) Add a new cgroup iterator to BPF with different traversal options, from Hao Luo. 5) Support for BPF to collect hierarchical cgroup statistics efficiently through BPF integration with the rstat framework, from Yosry Ahmed. 6) Support bpf_{g,s}et_retval() under more BPF cgroup hooks, from Stanislav Fomichev. 7) BPF hash table and local storages fixes under fully preemptible kernel, from Hou Tao. 8) Add various improvements to BPF selftests and libbpf for compilation with gcc BPF backend, from James Hilliard. 9) Fix verifier helper permissions and reference state management for synchronous callbacks, from Kumar Kartikeya Dwivedi. 10) Add support for BPF selftest's xskxceiver to also be used against real devices that support MAC loopback, from Maciej Fijalkowski. 11) Various fixes to the bpf-helpers(7) man page generation script, from Quentin Monnet. 12) Document BPF verifier's tnum_in(tnum_range(), ...) gotchas, from Shung-Hsi Yu. 13) Various minor misc improvements all over the place. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (106 commits) bpf: Optimize rcu_barrier usage between hash map and bpf_mem_alloc. bpf: Remove usage of kmem_cache from bpf_mem_cache. bpf: Remove prealloc-only restriction for sleepable bpf programs. bpf: Prepare bpf_mem_alloc to be used by sleepable bpf programs. bpf: Remove tracing program restriction on map types bpf: Convert percpu hash map to per-cpu bpf_mem_alloc. bpf: Add percpu allocation support to bpf_mem_alloc. bpf: Batch call_rcu callbacks instead of SLAB_TYPESAFE_BY_RCU. bpf: Adjust low/high watermarks in bpf_mem_cache bpf: Optimize call_rcu in non-preallocated hash map. bpf: Optimize element count in non-preallocated hash map. bpf: Relax the requirement to use preallocated hash maps in tracing progs. samples/bpf: Reduce syscall overhead in map_perf_test. selftests/bpf: Improve test coverage of test_maps bpf: Convert hash map to bpf_mem_alloc. bpf: Introduce any context BPF specific memory allocator. selftest/bpf: Add test for bpf_getsockopt() bpf: Change bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt() bpf: Change bpf_getsockopt(SOL_IP) to reuse do_ip_getsockopt() bpf: Change bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt() ... ==================== Link: https://lore.kernel.org/r/20220905161136.9150-1-daniel@iogearbox.net Signed-off-by: Paolo Abeni

bpftool: Add support for querying cgroup_iter link

2022-08-30T18:02:03Z

Support dumping info of a cgroup_iter link. This includes showing the cgroup's id and the order for walking the cgroup hierarchy. Example output is as follows: > bpftool link show 1: iter prog 2 target_name bpf_map 2: iter prog 3 target_name bpf_prog 3: iter prog 12 target_name cgroup cgroup_id 72 order self_only > bpftool -p link show [{ "id": 1, "type": "iter", "prog_id": 2, "target_name": "bpf_map" },{ "id": 2, "type": "iter", "prog_id": 3, "target_name": "bpf_prog" },{ "id": 3, "type": "iter", "prog_id": 12, "target_name": "cgroup", "cgroup_id": 72, "order": "self_only" } ] Signed-off-by: Hao Luo Reviewed-by: Quentin Monnet Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20220829231828.1016835-1-haoluo@google.com Signed-off-by: Martin KaFai Lau