aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/bpf/trampoline.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2024-05-14Merge tag 'net-next-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds1-11/+7
Pull networking updates from Jakub Kicinski: "Core & protocols: - Complete rework of garbage collection of AF_UNIX sockets. AF_UNIX is prone to forming reference count cycles due to fd passing functionality. New method based on Tarjan's Strongly Connected Components algorithm should be both faster and remove a lot of workarounds we accumulated over the years. - Add TCP fraglist GRO support, allowing chaining multiple TCP packets and forwarding them together. Useful for small switches / routers which lack basic checksum offload in some scenarios (e.g. PPPoE). - Support using SMP threads for handling packet backlog i.e. packet processing from software interfaces and old drivers which don't use NAPI. This helps move the processing out of the softirq jumble. - Continue work of converting from rtnl lock to RCU protection. Don't require rtnl lock when reading: IPv6 routing FIB, IPv6 address labels, netdev threaded NAPI sysfs files, bonding driver's sysfs files, MPLS devconf, IPv4 FIB rules, netns IDs, tcp metrics, TC Qdiscs, neighbor entries, ARP entries via ioctl(SIOCGARP), a lot of the link information available via rtnetlink. - Small optimizations from Eric to UDP wake up handling, memory accounting, RPS/RFS implementation, TCP packet sizing etc. - Allow direct page recycling in the bulk API used by XDP, for +2% PPS. - Support peek with an offset on TCP sockets. - Add MPTCP APIs for querying last time packets were received/sent/acked and whether MPTCP "upgrade" succeeded on a TCP socket. - Add intra-node communication shortcut to improve SMC performance. - Add IPv6 (and IPv{4,6}-over-IPv{4,6}) support to the GTP protocol driver. - Add HSR-SAN (RedBOX) mode of operation to the HSR protocol driver. - Add reset reasons for tracing what caused a TCP reset to be sent. - Introduce direction attribute for xfrm (IPSec) states. State can be used either for input or output packet processing. Things we sprinkled into general kernel code: - Add bitmap_{read,write}(), bitmap_size(), expose BYTES_TO_BITS(). This required touch-ups and renaming of a few existing users. - Add Endian-dependent __counted_by_{le,be} annotations. - Make building selftests "quieter" by printing summaries like "CC object.o" rather than full commands with all the arguments. Netfilter: - Use GFP_KERNEL to clone elements, to deal better with OOM situations and avoid failures in the .commit step. BPF: - Add eBPF JIT for ARCv2 CPUs. - Support attaching kprobe BPF programs through kprobe_multi link in a session mode, meaning, a BPF program is attached to both function entry and return, the entry program can decide if the return program gets executed and the entry program can share u64 cookie value with return program. "Session mode" is a common use-case for tetragon and bpftrace. - Add the ability to specify and retrieve BPF cookie for raw tracepoint programs in order to ease migration from classic to raw tracepoints. - Add an internal-only BPF per-CPU instruction for resolving per-CPU memory addresses and implement support in x86, ARM64 and RISC-V JITs. This allows inlining functions which need to access per-CPU state. - Optimize x86 BPF JIT's emit_mov_imm64, and add support for various atomics in bpf_arena which can be JITed as a single x86 instruction. Support BPF arena on ARM64. - Add a new bpf_wq API for deferring events and refactor process-context bpf_timer code to keep common code where possible. - Harden the BPF verifier's and/or/xor value tracking. - Introduce crypto kfuncs to let BPF programs call kernel crypto APIs. - Support bpf_tail_call_static() helper for BPF programs with GCC 13. - Add bpf_preempt_{disable,enable}() kfuncs in order to allow a BPF program to have code sections where preemption is disabled. Driver API: - Skip software TC processing completely if all installed rules are marked as HW-only, instead of checking the HW-only flag rule by rule. - Add support for configuring PoE (Power over Ethernet), similar to the already existing support for PoDL (Power over Data Line) config. - Initial bits of a queue control API, for now allowing a single queue to be reset without disturbing packet flow to other queues. - Common (ethtool) statistics for hardware timestamping. Tests and tooling: - Remove the need to create a config file to run the net forwarding tests so that a naive "make run_tests" can exercise them. - Define a method of writing tests which require an external endpoint to communicate with (to send/receive data towards the test machine). Add a few such tests. - Create a shared code library for writing Python tests. Expose the YAML Netlink library from tools/ to the tests for easy Netlink access. - Move netfilter tests under net/, extend them, separate performance tests from correctness tests, and iron out issues found by running them "on every commit". - Refactor BPF selftests to use common network helpers. - Further work filling in YAML definitions of Netlink messages for: nftables, team driver, bonding interfaces, vlan interfaces, VF info, TC u32 mark, TC police action. - Teach Python YAML Netlink to decode attribute policies. - Extend the definition of the "indexed array" construct in the specs to cover arrays of scalars rather than just nests. - Add hyperlinks between definitions in generated Netlink docs. Drivers: - Make sure unsupported flower control flags are rejected by drivers, and make more drivers report errors directly to the application rather than dmesg (large number of driver changes from Asbjørn Sloth Tønnesen). - Ethernet high-speed NICs: - Broadcom (bnxt): - support multiple RSS contexts and steering traffic to them - support XDP metadata - make page pool allocations more NUMA aware - Intel (100G, ice, idpf): - extract datapath code common among Intel drivers into a library - use fewer resources in switchdev by sharing queues with the PF - add PFCP filter support - add Ethernet filter support - use a spinlock instead of HW lock in PTP clock ops - support 5 layer Tx scheduler topology - nVidia/Mellanox: - 800G link modes and 100G SerDes speeds - per-queue IRQ coalescing configuration - Marvell Octeon: - support offloading TC packet mark action - Ethernet NICs consumer, embedded and virtual: - stop lying about skb->truesize in USB Ethernet drivers, it messes up TCP memory calculations - Google cloud vNIC: - support changing ring size via ethtool - support ring reset using the queue control API - VirtIO net: - expose flow hash from RSS to XDP - per-queue statistics - add selftests - Synopsys (stmmac): - support controllers which require an RX clock signal from the MII bus to perform their hardware initialization - TI: - icssg_prueth: support ICSSG-based Ethernet on AM65x SR1.0 devices - icssg_prueth: add SW TX / RX Coalescing based on hrtimers - cpsw: minimal XDP support - Renesas (ravb): - support describing the MDIO bus - Realtek (r8169): - add support for RTL8168M - Microchip Sparx5: - matchall and flower actions mirred and redirect - Ethernet switches: - nVidia/Mellanox: - improve events processing performance - Marvell: - add support for MV88E6250 family internal PHYs - Microchip: - add DCB and DSCP mapping support for KSZ switches - vsc73xx: convert to PHYLINK - Realtek: - rtl8226b/rtl8221b: add C45 instances and SerDes switching - Many driver changes related to PHYLIB and PHYLINK deprecated API cleanup - Ethernet PHYs: - Add a new driver for Airoha EN8811H 2.5 Gigabit PHY. - micrel: lan8814: add support for PPS out and external timestamp trigger - WiFi: - Disable Wireless Extensions (WEXT) in all Wi-Fi 7 devices drivers. Modern devices can only be configured using nl80211. - mac80211/cfg80211 - handle color change per link for WiFi 7 Multi-Link Operation - Intel (iwlwifi): - don't support puncturing in 5 GHz - support monitor mode on passive channels - BZ-W device support - P2P with HE/EHT support - re-add support for firmware API 90 - provide channel survey information for Automatic Channel Selection - MediaTek (mt76): - mt7921 LED control - mt7925 EHT radiotap support - mt7920e PCI support - Qualcomm (ath11k): - P2P support for QCA6390, WCN6855 and QCA2066 - support hibernation - ieee80211-freq-limit Device Tree property support - Qualcomm (ath12k): - refactoring in preparation of multi-link support - suspend and hibernation support - ACPI support - debugfs support, including dfs_simulate_radar support - RealTek: - rtw88: RTL8723CS SDIO device support - rtw89: RTL8922AE Wi-Fi 7 PCI device support - rtw89: complete features of new WiFi 7 chip 8922AE including BT-coexistence and Wake-on-WLAN - rtw89: use BIOS ACPI settings to set TX power and channels - rtl8xxxu: enable Management Frame Protection (MFP) support - Bluetooth: - support for Intel BlazarI and Filmore Peak2 (BE201) - support for MediaTek MT7921S SDIO - initial support for Intel PCIe BT driver - remove HCI_AMP support" * tag 'net-next-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1827 commits) selftests: netfilter: fix packetdrill conntrack testcase net: gro: fix napi_gro_cb zeroed alignment Bluetooth: btintel_pcie: Refactor and code cleanup Bluetooth: btintel_pcie: Fix warning reported by sparse Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1 Bluetooth: btintel: Fix compiler warning for multi_v7_defconfig config Bluetooth: btintel_pcie: Fix compiler warnings Bluetooth: btintel_pcie: Add *setup* function to download firmware Bluetooth: btintel_pcie: Add support for PCIe transport Bluetooth: btintel: Export few static functions Bluetooth: HCI: Remove HCI_AMP support Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init() Bluetooth: qca: Fix error code in qca_read_fw_build_info() Bluetooth: hci_conn: Use __counted_by() and avoid -Wfamnae warning Bluetooth: btintel: Add support for Filmore Peak2 (BE201) Bluetooth: btintel: Add support for BlazarI LE Create Connection command timeout increased to 20 secs dt-bindings: net: bluetooth: Add MediaTek MT7921S SDIO Bluetooth Bluetooth: compute LE flow credits based on recvbuf space Bluetooth: hci_sync: Use cmd->num_cis instead of magic number ...
2024-04-12bpf: Choose RCU Tasks based on TASKS_RCU rather than PREEMPTIONPaul E. McKenney1-1/+1
The advent of CONFIG_PREEMPT_AUTO, AKA lazy preemption, will mean that even kernels built with CONFIG_PREEMPT_NONE or CONFIG_PREEMPT_VOLUNTARY might see the occasional preemption, and that this preemption just might happen within a trampoline. Therefore, update bpf_tramp_image_put() to choose call_rcu_tasks() based on CONFIG_TASKS_RCU instead of CONFIG_PREEMPTION. This change might enable further simplifications, but the goal of this effort is to make the code safe, not necessarily optimal. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Song Liu <song@kernel.org> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: KP Singh <kpsingh@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Ankur Arora <ankur.a.arora@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <bpf@vger.kernel.org> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
2024-04-02bpf: Improve program stats run-time calculationJose Fernandez1-1/+2
This patch improves the run-time calculation for program stats by capturing the duration as soon as possible after the program returns. Previously, the duration included u64_stats_t operations. While the instrumentation overhead is part of the total time spent when stats are enabled, distinguishing between the program's native execution time and the time spent due to instrumentation is crucial for accurate performance analysis. By making this change, the patch facilitates more precise optimization of BPF programs, enabling users to understand their performance in environments without stats enabled. I used a virtualized environment to measure the run-time over one minute for a basic raw_tracepoint/sys_enter program, which just increments a local counter. Although the virtualization introduced some performance degradation that could affect the results, I observed approximately a 16% decrease in average run-time reported by stats with this change (310 -> 260 nsec). Signed-off-by: Jose Fernandez <josef@netflix.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240402034010.25060-1-josef@netflix.com
2024-03-18bpf: Check return from set_memory_rox()Christophe Leroy1-3/+5
arch_protect_bpf_trampoline() and alloc_new_pack() call set_memory_rox() which can fail, leading to unprotected memory. Take into account return from set_memory_rox() function and add __must_check flag to arch_protect_bpf_trampoline(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/fe1c163c83767fde5cab31d209a4a6be3ddb3a73.1710574353.git.christophe.leroy@csgroup.eu Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-18bpf: Remove arch_unprotect_bpf_trampoline()Christophe Leroy1-7/+0
Last user of arch_unprotect_bpf_trampoline() was removed by commit 187e2af05abe ("bpf: struct_ops supports more than one page for trampolines.") Remove arch_unprotect_bpf_trampoline() Reported-by: Daniel Borkmann <daniel@iogearbox.net> Fixes: 187e2af05abe ("bpf: struct_ops supports more than one page for trampolines.") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://lore.kernel.org/r/42c635bb54d3af91db0f9b85d724c7c290069f67.1710574353.git.christophe.leroy@csgroup.eu Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-11bpf: move sleepable flag from bpf_prog_aux to bpf_progAndrii Nakryiko1-2/+2
prog->aux->sleepable is checked very frequently as part of (some) BPF program run hot paths. So this extra aux indirection seems wasteful and on busy systems might cause unnecessary memory cache misses. Let's move sleepable flag into prog itself to eliminate unnecessary pointer dereference. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Message-ID: <20240309004739.2961431-1-andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-06bpf: Use arch_bpf_trampoline_sizeSong Liu1-21/+34
Instead of blindly allocating PAGE_SIZE for each trampoline, check the size of the trampoline with arch_bpf_trampoline_size(). This size is saved in bpf_tramp_image->size, and used for modmem charge/uncharge. The fallback arch_alloc_bpf_trampoline() still allocates a whole page because we need to use set_memory_* to protect the memory. struct_ops trampoline still uses a whole page for multiple trampolines. With this size check at caller (regular trampoline and struct_ops trampoline), remove arch_bpf_trampoline_size() from arch_prepare_bpf_trampoline() in archs. Also, update bpf_image_ksym_add() to handle symbol of different sizes. Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Björn Töpel <bjorn@rivosinc.com> # on riscv Link: https://lore.kernel.org/r/20231206224054.492250-7-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-06bpf: Add arch_bpf_trampoline_size()Song Liu1-0/+6
This helper will be used to calculate the size of the trampoline before allocating the memory. arch_prepare_bpf_trampoline() for arm64 and riscv64 can use arch_bpf_trampoline_size() to check the trampoline fits in the image. OTOH, arch_prepare_bpf_trampoline() for s390 has to call the JIT process twice, so it cannot use arch_bpf_trampoline_size(). Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Björn Töpel <bjorn@rivosinc.com> # on riscv Link: https://lore.kernel.org/r/20231206224054.492250-6-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-06bpf: Add helpers for trampoline image managementSong Liu1-7/+39
As BPF trampoline of different archs moves from bpf_jit_[alloc|free]_exec() to bpf_prog_pack_[alloc|free](), we need to use different _alloc, _free for different archs during the transition. Add the following helpers for this transition: void *arch_alloc_bpf_trampoline(unsigned int size); void arch_free_bpf_trampoline(void *image, unsigned int size); void arch_protect_bpf_trampoline(void *image, unsigned int size); void arch_unprotect_bpf_trampoline(void *image, unsigned int size); The fallback version of these helpers require size <= PAGE_SIZE, but they are only called with size == PAGE_SIZE. They will be called with size < PAGE_SIZE when arch_bpf_trampoline_size() helper is introduced later. Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20231206224054.492250-4-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-06bpf: Adjust argument names of arch_prepare_bpf_trampoline()Song Liu1-2/+2
We are using "im" for "struct bpf_tramp_image" and "tr" for "struct bpf_trampoline" in most of the code base. The only exception is the prototype and fallback version of arch_prepare_bpf_trampoline(). Update them to match the rest of the code base. We mix "orig_call" and "func_addr" for the argument in different versions of arch_prepare_bpf_trampoline(). s/orig_call/func_addr/g so they match. Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20231206224054.492250-3-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-12bpf, x64: Fix tailcall infinite loopLeon Hwang1-2/+2
From commit ebf7d1f508a73871 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT"), the tailcall on x64 works better than before. From commit e411901c0b775a3a ("bpf: allow for tailcalls in BPF subprograms for x64 JIT"), tailcall is able to run in BPF subprograms on x64. From commit 5b92a28aae4dd0f8 ("bpf: Support attaching tracing BPF program to other BPF programs"), BPF program is able to trace other BPF programs. How about combining them all together? 1. FENTRY/FEXIT on a BPF subprogram. 2. A tailcall runs in the BPF subprogram. 3. The tailcall calls the subprogram's caller. As a result, a tailcall infinite loop comes up. And the loop would halt the machine. As we know, in tail call context, the tail_call_cnt propagates by stack and rax register between BPF subprograms. So do in trampolines. Fixes: ebf7d1f508a7 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT") Fixes: e411901c0b77 ("bpf: allow for tailcalls in BPF subprograms for x64 JIT") Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Signed-off-by: Leon Hwang <hffilwlqm@gmail.com> Link: https://lore.kernel.org/r/20230912150442.2009-3-hffilwlqm@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-06bpf: Assign bpf_tramp_run_ctx::saved_run_ctx before recursion check.Sebastian Andrzej Siewior1-3/+2
__bpf_prog_enter_recur() assigns bpf_tramp_run_ctx::saved_run_ctx before performing the recursion check which means in case of a recursion __bpf_prog_exit_recur() uses the previously set bpf_tramp_run_ctx::saved_run_ctx value. __bpf_prog_enter_sleepable_recur() assigns bpf_tramp_run_ctx::saved_run_ctx after the recursion check which means in case of a recursion __bpf_prog_exit_sleepable_recur() uses an uninitialized value. This does not look right. If I read the entry trampoline code right, then bpf_tramp_run_ctx isn't initialized upfront. Align __bpf_prog_enter_sleepable_recur() with __bpf_prog_enter_recur() and set bpf_tramp_run_ctx::saved_run_ctx before the recursion check is made. Remove the assignment of saved_run_ctx in kern_sys_bpf() since it happens a few cycles later. Fixes: e384c7b7b46d0 ("bpf, x86: Create bpf_tramp_run_ctx on the caller thread's stack") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20230830080405.251926-3-bigeasy@linutronix.de
2023-05-15bpf: Fix memleak due to fentry attach failureYafang Shao1-6/+15
If it fails to attach fentry, the allocated bpf trampoline image will be left in the system. That can be verified by checking /proc/kallsyms. This meamleak can be verified by a simple bpf program as follows: SEC("fentry/trap_init") int fentry_run() { return 0; } It will fail to attach trap_init because this function is freed after kernel init, and then we can find the trampoline image is left in the system by checking /proc/kallsyms. $ tail /proc/kallsyms ffffffffc0613000 t bpf_trampoline_6442453466_1 [bpf] ffffffffc06c3000 t bpf_trampoline_6442453466_1 [bpf] $ bpftool btf dump file /sys/kernel/btf/vmlinux | grep "FUNC 'trap_init'" [2522] FUNC 'trap_init' type_id=119 linkage=static $ echo $((6442453466 & 0x7fffffff)) 2522 Note that there are two left bpf trampoline images, that is because the libbpf will fallback to raw tracepoint if -EINVAL is returned. Fixes: e21aa341785c ("bpf: Fix fexit trampoline.") Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <song@kernel.org> Cc: Jiri Olsa <olsajiri@gmail.com> Link: https://lore.kernel.org/bpf/20230515130849.57502-2-laoar.shao@gmail.com
2023-05-15bpf: Remove bpf trampoline selectorYafang Shao1-7/+4
After commit e21aa341785c ("bpf: Fix fexit trampoline."), the selector is only used to indicate how many times the bpf trampoline image are updated and been displayed in the trampoline ksym name. After the trampoline is freed, the selector will start from 0 again. So the selector is a useless value to the user. We can remove it. If the user want to check whether the bpf trampoline image has been updated or not, the user can compare the address. Each time the trampoline image is updated, the address will change consequently. Jiri also pointed out another issue that perf is still using the old name "bpf_trampoline_%lu", so this change can fix the issue in perf. Fixes: e21aa341785c ("bpf: Fix fexit trampoline.") Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <song@kernel.org> Cc: Jiri Olsa <olsajiri@gmail.com> Link: https://lore.kernel.org/bpf/ZFvOOlrmHiY9AgXE@krava Link: https://lore.kernel.org/bpf/20230515130849.57502-3-laoar.shao@gmail.com
2023-04-26Merge tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds1-28/+0
Pull networking updates from Paolo Abeni: "Core: - Introduce a config option to tweak MAX_SKB_FRAGS. Increasing the default value allows for better BIG TCP performances - Reduce compound page head access for zero-copy data transfers - RPS/RFS improvements, avoiding unneeded NET_RX_SOFTIRQ when possible - Threaded NAPI improvements, adding defer skb free support and unneeded softirq avoidance - Address dst_entry reference count scalability issues, via false sharing avoidance and optimize refcount tracking - Add lockless accesses annotation to sk_err[_soft] - Optimize again the skb struct layout - Extends the skb drop reasons to make it usable by multiple subsystems - Better const qualifier awareness for socket casts BPF: - Add skb and XDP typed dynptrs which allow BPF programs for more ergonomic and less brittle iteration through data and variable-sized accesses - Add a new BPF netfilter program type and minimal support to hook BPF programs to netfilter hooks such as prerouting or forward - Add more precise memory usage reporting for all BPF map types - Adds support for using {FOU,GUE} encap with an ipip device operating in collect_md mode and add a set of BPF kfuncs for controlling encap params - Allow BPF programs to detect at load time whether a particular kfunc exists or not, and also add support for this in light skeleton - Bigger batch of BPF verifier improvements to prepare for upcoming BPF open-coded iterators allowing for less restrictive looping capabilities - Rework RCU enforcement in the verifier, add kptr_rcu and enforce BPF programs to NULL-check before passing such pointers into kfunc - Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and in local storage maps - Enable RCU semantics for task BPF kptrs and allow referenced kptr tasks to be stored in BPF maps - Add support for refcounted local kptrs to the verifier for allowing shared ownership, useful for adding a node to both the BPF list and rbtree - Add BPF verifier support for ST instructions in convert_ctx_access() which will help new -mcpu=v4 clang flag to start emitting them - Add ARM32 USDT support to libbpf - Improve bpftool's visual program dump which produces the control flow graph in a DOT format by adding C source inline annotations Protocols: - IPv4: Allow adding to IPv4 address a 'protocol' tag. Such value indicates the provenance of the IP address - IPv6: optimize route lookup, dropping unneeded R/W lock acquisition - Add the handshake upcall mechanism, allowing the user-space to implement generic TLS handshake on kernel's behalf - Bridge: support per-{Port, VLAN} neighbor suppression, increasing resilience to nodes failures - SCTP: add support for Fair Capacity and Weighted Fair Queueing schedulers - MPTCP: delay first subflow allocation up to its first usage. This will allow for later better LSM interaction - xfrm: Remove inner/outer modes from input/output path. These are not needed anymore - WiFi: - reduced neighbor report (RNR) handling for AP mode - HW timestamping support - support for randomized auth/deauth TA for PASN privacy - per-link debugfs for multi-link - TC offload support for mac80211 drivers - mac80211 mesh fast-xmit and fast-rx support - enable Wi-Fi 7 (EHT) mesh support Netfilter: - Add nf_tables 'brouting' support, to force a packet to be routed instead of being bridged - Update bridge netfilter and ovs conntrack helpers to handle IPv6 Jumbo packets properly, i.e. fetch the packet length from hop-by-hop extension header. This is needed for BIT TCP support - The iptables 32bit compat interface isn't compiled in by default anymore - Move ip(6)tables builtin icmp matches to the udptcp one. This has the advantage that icmp/icmpv6 match doesn't load the iptables/ip6tables modules anymore when iptables-nft is used - Extended netlink error report for netdevice in flowtables and netdev/chains. Allow for incrementally add/delete devices to netdev basechain. Allow to create netdev chain without device Driver API: - Remove redundant Device Control Error Reporting Enable, as PCI core has already error reporting enabled at enumeration time - Move Multicast DB netlink handlers to core, allowing devices other then bridge to use them - Allow the page_pool to directly recycle the pages from safely localized NAPI - Implement lockless TX queue stop/wake combo macros, allowing for further code de-duplication and sanitization - Add YNL support for user headers and struct attrs - Add partial YNL specification for devlink - Add partial YNL specification for ethtool - Add tc-mqprio and tc-taprio support for preemptible traffic classes - Add tx push buf len param to ethtool, specifies the maximum number of bytes of a transmitted packet a driver can push directly to the underlying device - Add basic LED support for switch/phy - Add NAPI documentation, stop relaying on external links - Convert dsa_master_ioctl() to netdev notifier. This is a preparatory work to make the hardware timestamping layer selectable by user space - Add transceiver support and improve the error messages for CAN-FD controllers New hardware / drivers: - Ethernet: - AMD/Pensando core device support - MediaTek MT7981 SoC - MediaTek MT7988 SoC - Broadcom BCM53134 embedded switch - Texas Instruments CPSW9G ethernet switch - Qualcomm EMAC3 DWMAC ethernet - StarFive JH7110 SoC - NXP CBTX ethernet PHY - WiFi: - Apple M1 Pro/Max devices - RealTek rtl8710bu/rtl8188gu - RealTek rtl8822bs, rtl8822cs and rtl8821cs SDIO chipset - Bluetooth: - Realtek RTL8821CS, RTL8851B, RTL8852BS - Mediatek MT7663, MT7922 - NXP w8997 - Actions Semi ATS2851 - QTI WCN6855 - Marvell 88W8997 - Can: - STMicroelectronics bxcan stm32f429 Drivers: - Ethernet NICs: - Intel (1G, icg): - add tracking and reporting of QBV config errors - add support for configuring max SDU for each Tx queue - Intel (100G, ice): - refactor mailbox overflow detection to support Scalable IOV - GNSS interface optimization - Intel (i40e): - support XDP multi-buffer - nVidia/Mellanox: - add the support for linux bridge multicast offload - enable TC offload for egress and engress MACVLAN over bond - add support for VxLAN GBP encap/decap flows offload - extend packet offload to fully support libreswan - support tunnel mode in mlx5 IPsec packet offload - extend XDP multi-buffer support - support MACsec VLAN offload - add support for dynamic msix vectors allocation - drop RX page_cache and fully use page_pool - implement thermal zone to report NIC temperature - Netronome/Corigine: - add support for multi-zone conntrack offload - Solarflare/Xilinx: - support offloading TC VLAN push/pop actions to the MAE - support TC decap rules - support unicast PTP - Other NICs: - Broadcom (bnxt): enforce software based freq adjustments only on shared PHC NIC - RealTek (r8169): refactor to addess ASPM issues during NAPI poll - Micrel (lan8841): add support for PTP_PF_PEROUT - Cadence (macb): enable PTP unicast - Engleder (tsnep): add XDP socket zero-copy support - virtio-net: implement exact header length guest feature - veth: add page_pool support for page recycling - vxlan: add MDB data path support - gve: add XDP support for GQI-QPL format - geneve: accept every ethertype - macvlan: allow some packets to bypass broadcast queue - mana: add support for jumbo frame - Ethernet high-speed switches: - Microchip (sparx5): Add support for TC flower templates - Ethernet embedded switches: - Broadcom (b54): - configure 6318 and 63268 RGMII ports - Marvell (mv88e6xxx): - faster C45 bus scan - Microchip: - lan966x: - add support for IS1 VCAP - better TX/RX from/to CPU performances - ksz9477: add ETS Qdisc support - ksz8: enhance static MAC table operations and error handling - sama7g5: add PTP capability - NXP (ocelot): - add support for external ports - add support for preemptible traffic classes - Texas Instruments: - add CPSWxG SGMII support for J7200 and J721E - Intel WiFi (iwlwifi): - preparation for Wi-Fi 7 EHT and multi-link support - EHT (Wi-Fi 7) sniffer support - hardware timestamping support for some devices/firwmares - TX beacon protection on newer hardware - Qualcomm 802.11ax WiFi (ath11k): - MU-MIMO parameters support - ack signal support for management packets - RealTek WiFi (rtw88): - SDIO bus support - better support for some SDIO devices (e.g. MAC address from efuse) - RealTek WiFi (rtw89): - HW scan support for 8852b - better support for 6 GHz scanning - support for various newer firmware APIs - framework firmware backwards compatibility - MediaTek WiFi (mt76): - P2P support - mesh A-MSDU support - EHT (Wi-Fi 7) support - coredump support" * tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2078 commits) net: phy: hide the PHYLIB_LEDS knob net: phy: marvell-88x2222: remove unnecessary (void*) conversions tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp. net: amd: Fix link leak when verifying config failed net: phy: marvell: Fix inconsistent indenting in led_blink_set lan966x: Don't use xdp_frame when action is XDP_TX tsnep: Add XDP socket zero-copy TX support tsnep: Add XDP socket zero-copy RX support tsnep: Move skb receive action to separate function tsnep: Add functions for queue enable/disable tsnep: Rework TX/RX queue initialization tsnep: Replace modulo operation with mask net: phy: dp83867: Add led_brightness_set support net: phy: Fix reading LED reg property drivers: nfc: nfcsim: remove return value check of `dev_dir` net: phy: dp83867: Remove unnecessary (void*) conversions net: ethtool: coalesce: try to make user settings stick twice net: mana: Check if netdev/napi_alloc_frag returns single page net: mana: Rename mana_refill_rxoob and remove some empty lines net: veth: add page_pool stats ...
2023-03-21ftrace: Rename _ftrace_direct_multi APIs to _ftrace_direct APIsFlorent Revest1-6/+6
Now that the original _ftrace_direct APIs are gone, the "_multi" suffixes only add confusion. Link: https://lkml.kernel.org/r/20230321140424.345218-5-revest@chromium.org Signed-off-by: Florent Revest <revest@chromium.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-03-21ftrace: Let unregister_ftrace_direct_multi() call ftrace_free_filter()Florent Revest1-1/+1
A common pattern when using the ftrace_direct_multi API is to unregister the ops and also immediately free its filter. We've noticed it's very easy for users to miss calling ftrace_free_filter(). This adds a "free_filters" argument to unregister_ftrace_direct_multi() to both remind the user they should free filters and also to make their life easier. Link: https://lkml.kernel.org/r/20230321140424.345218-2-revest@chromium.org Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Florent Revest <revest@chromium.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-03-15bpf: Fix attaching fentry/fexit/fmod_ret/lsm to modulesViktor Malik1-28/+0
This resolves two problems with attachment of fentry/fexit/fmod_ret/lsm to functions located in modules: 1. The verifier tries to find the address to attach to in kallsyms. This is always done by searching the entire kallsyms, not respecting the module in which the function is located. Such approach causes an incorrect attachment address to be computed if the function to attach to is shadowed by a function of the same name located earlier in kallsyms. 2. If the address to attach to is located in a module, the module reference is only acquired in register_fentry. If the module is unloaded between the place where the address is found (bpf_check_attach_target in the verifier) and register_fentry, it is possible that another module is loaded to the same address which may lead to potential errors. Since the attachment must contain the BTF of the program to attach to, we extract the module from it and search for the function address in the correct module (resolving problem no. 1). Then, the module reference is taken directly in bpf_check_attach_target and stored in the bpf program (in bpf_prog_aux). The reference is only released when the program is unloaded (resolving problem no. 2). Signed-off-by: Viktor Malik <vmalik@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/3f6a9d8ae850532b5ef864ef16327b0f7a669063.1678432753.git.vmalik@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-28bpf: Fix panic due to wrong pageattr of im->imageChuang Wang1-0/+4
In the scenario where livepatch and kretfunc coexist, the pageattr of im->image is rox after arch_prepare_bpf_trampoline in bpf_trampoline_update, and then modify_fentry or register_fentry returns -EAGAIN from bpf_tramp_ftrace_ops_func, the BPF_TRAMP_F_ORIG_STACK flag will be configured, and arch_prepare_bpf_trampoline will be re-executed. At this time, because the pageattr of im->image is rox, arch_prepare_bpf_trampoline will read and write im->image, which causes a fault. as follows: insmod livepatch-sample.ko # samples/livepatch/livepatch-sample.c bpftrace -e 'kretfunc:cmdline_proc_show {}' BUG: unable to handle page fault for address: ffffffffa0206000 PGD 322d067 P4D 322d067 PUD 322e063 PMD 1297e067 PTE d428061 Oops: 0003 [#1] PREEMPT SMP PTI CPU: 2 PID: 270 Comm: bpftrace Tainted: G E K 6.1.0 #5 RIP: 0010:arch_prepare_bpf_trampoline+0xed/0x8c0 RSP: 0018:ffffc90001083ad8 EFLAGS: 00010202 RAX: ffffffffa0206000 RBX: 0000000000000020 RCX: 0000000000000000 RDX: ffffffffa0206001 RSI: ffffffffa0206000 RDI: 0000000000000030 RBP: ffffc90001083b70 R08: 0000000000000066 R09: ffff88800f51b400 R10: 000000002e72c6e5 R11: 00000000d0a15080 R12: ffff8880110a68c8 R13: 0000000000000000 R14: ffff88800f51b400 R15: ffffffff814fec10 FS: 00007f87bc0dc780(0000) GS:ffff88803e600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffa0206000 CR3: 0000000010b70000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> bpf_trampoline_update+0x25a/0x6b0 __bpf_trampoline_link_prog+0x101/0x240 bpf_trampoline_link_prog+0x2d/0x50 bpf_tracing_prog_attach+0x24c/0x530 bpf_raw_tp_link_attach+0x73/0x1d0 __sys_bpf+0x100e/0x2570 __x64_sys_bpf+0x1c/0x30 do_syscall_64+0x5b/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd With this patch, when modify_fentry or register_fentry returns -EAGAIN from bpf_tramp_ftrace_ops_func, the pageattr of im->image will be reset to nx+rw. Cc: stable@vger.kernel.org Fixes: 00963a2e75a8 ("bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)") Signed-off-by: Chuang Wang <nashuiliang@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20221224133146.780578-1-nashuiliang@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-17Merge tag 'x86_mm_for_6.2_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-2/+1
Pull x86 mm updates from Dave Hansen: "New Feature: - Randomize the per-cpu entry areas Cleanups: - Have CR3_ADDR_MASK use PHYSICAL_PAGE_MASK instead of open coding it - Move to "native" set_memory_rox() helper - Clean up pmd_get_atomic() and i386-PAE - Remove some unused page table size macros" * tag 'x86_mm_for_6.2_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) x86/mm: Ensure forced page table splitting x86/kasan: Populate shadow for shared chunk of the CPU entry area x86/kasan: Add helpers to align shadow addresses up and down x86/kasan: Rename local CPU_ENTRY_AREA variables to shorten names x86/mm: Populate KASAN shadow for entire per-CPU range of CPU entry area x86/mm: Recompute physical address for every page of per-CPU CEA mapping x86/mm: Rename __change_page_attr_set_clr(.checkalias) x86/mm: Inhibit _PAGE_NX changes from cpa_process_alias() x86/mm: Untangle __change_page_attr_set_clr(.checkalias) x86/mm: Add a few comments x86/mm: Fix CR3_ADDR_MASK x86/mm: Remove P*D_PAGE_MASK and P*D_PAGE_SIZE macros mm: Convert __HAVE_ARCH_P..P_GET to the new style mm: Remove pointless barrier() after pmdp_get_lockless() x86/mm/pae: Get rid of set_64bit() x86_64: Remove pointless set_64bit() usage x86/mm/pae: Be consistent with pXXp_get_and_clear() x86/mm/pae: Use WRITE_ONCE() x86/mm/pae: Don't (ab)use atomic64 mm/gup: Fix the lockless PMD access ...
2022-12-15mm: Introduce set_memory_rox()Peter Zijlstra1-2/+1
Because endlessly repeating: set_memory_ro() set_memory_x() is getting tedious. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/Y1jek64pXOsougmz@hirez.programming.kicks-ass.net
2022-10-25bpf: Remove prog->active check for bpf_lsm and bpf_iterMartin KaFai Lau1-13/+67
The commit 64696c40d03c ("bpf: Add __bpf_prog_{enter,exit}_struct_ops for struct_ops trampoline") removed prog->active check for struct_ops prog. The bpf_lsm and bpf_iter is also using trampoline. Like struct_ops, the bpf_lsm and bpf_iter have fixed hooks for the prog to attach. The kernel does not call the same hook in a recursive way. This patch also removes the prog->active check for bpf_lsm and bpf_iter. A later patch has a test to reproduce the recursion issue for a sleepable bpf_lsm program. This patch appends the '_recur' naming to the existing enter and exit functions that track the prog->active counter. New __bpf_prog_{enter,exit}[_sleepable] function are added to skip the prog->active tracking. The '_struct_ops' version is also removed. It also moves the decision on picking the enter and exit function to the new bpf_trampoline_{enter,exit}(). It returns the '_recur' ones for all tracing progs to use. For bpf_lsm, bpf_iter, struct_ops (no prog->active tracking after 64696c40d03c), and bpf_lsm_cgroup (no prog->active tracking after 69fd337a975c7), it will return the functions that don't track the prog->active. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20221025184524.3526117-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-29bpf: Add __bpf_prog_{enter,exit}_struct_ops for struct_ops trampolineMartin KaFai Lau1-0/+23
The struct_ops prog is to allow using bpf to implement the functions in a struct (eg. kernel module). The current usage is to implement the tcp_congestion. The kernel does not call the tcp-cc's ops (ie. the bpf prog) in a recursive way. The struct_ops is sharing the tracing-trampoline's enter/exit function which tracks prog->active to avoid recursion. It is needed for tracing prog. However, it turns out the struct_ops bpf prog will hit this prog->active and unnecessarily skipped running the struct_ops prog. eg. The '.ssthresh' may run in_task() and then interrupted by softirq that runs the same '.ssthresh'. Skip running the '.ssthresh' will end up returning random value to the caller. The patch adds __bpf_prog_{enter,exit}_struct_ops for the struct_ops trampoline. They do not track the prog->active to detect recursion. One exception is when the tcp_congestion's '.init' ops is doing bpf_setsockopt(TCP_CONGESTION) and then recurs to the same '.init' ops. This will be addressed in the following patches. Fixes: ca06f55b9002 ("bpf: Add per-program recursion prevention mechanism") Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20220929070407.965581-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-26bpf: Enforce W^X for bpf trampolineSong Liu1-17/+5
Mark the trampoline as RO+X after arch_prepare_bpf_trampoline, so that the trampoine follows W^X rule strictly. This will turn off warnings like CPA refuse W^X violation: 8000000000000163 -> 0000000000000163 range: ... Also remove bpf_jit_alloc_exec_page(), since it is not used any more. Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20220926184739.3512547-3-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-21bpf: Prevent bpf program recursion for raw tracepoint probesJiri Olsa1-13/+2
We got report from sysbot [1] about warnings that were caused by bpf program attached to contention_begin raw tracepoint triggering the same tracepoint by using bpf_trace_printk helper that takes trace_printk_lock lock. Call Trace: <TASK> ? trace_event_raw_event_bpf_trace_printk+0x5f/0x90 bpf_trace_printk+0x2b/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 bpf_trace_printk+0x3f/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 bpf_trace_printk+0x3f/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 bpf_trace_printk+0x3f/0xe0 bpf_prog_a9aec6167c091eef_prog+0x1f/0x24 bpf_trace_run2+0x26/0x90 native_queued_spin_lock_slowpath+0x1c6/0x2b0 _raw_spin_lock_irqsave+0x44/0x50 __unfreeze_partials+0x5b/0x160 ... The can be reproduced by attaching bpf program as raw tracepoint on contention_begin tracepoint. The bpf prog calls bpf_trace_printk helper. Then by running perf bench the spin lock code is forced to take slow path and call contention_begin tracepoint. Fixing this by skipping execution of the bpf program if it's already running, Using bpf prog 'active' field, which is being currently used by trampoline programs for the same reason. Moving bpf_prog_inc_misses_counter to syscall.c because trampoline.c is compiled in just for CONFIG_BPF_JIT option. Reviewed-by: Stanislav Fomichev <sdf@google.com> Reported-by: syzbot+2251879aa068ad9c960d@syzkaller.appspotmail.com [1] https://lore.kernel.org/bpf/YxhFe3EwqchC%2FfYf@krava/T/#t Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20220916071914.7156-1-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-01bpf: Use this_cpu_{inc_return|dec} for prog->activeHou Tao1-4/+4
Both __this_cpu_inc_return() and __this_cpu_dec() are not preemption safe and now migrate_disable() doesn't disable preemption, so the update of prog-active is not atomic and in theory under fully preemptible kernel recurisve prevention may do not work. Fixing by using the preemption-safe and IRQ-safe variants. Fixes: ca06f55b9002 ("bpf: Add per-program recursion prevention mechanism") Signed-off-by: Hou Tao <houtao1@huawei.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20220901061938.3789460-3-houtao@huaweicloud.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-08-05bpf: Cleanup ftrace hash in bpf_trampoline_putJiri Olsa1-1/+4
We need to release possible hash from trampoline fops object before removing it, otherwise we leak it. Fixes: 00963a2e75a8 ("bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20220802135651.1794015-1-jolsa@kernel.org
2022-07-29bpf: Remove unneeded semicolonYang Li1-1/+1
Eliminate the following coccicheck warning: /kernel/bpf/trampoline.c:101:2-3: Unneeded semicolon Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220725222733.55613-1-yang.lee@linux.alibaba.com
2022-07-29bpf: Fix NULL pointer dereference when registering bpf trampolineXu Kuohai1-1/+4
A panic was reported on arm64: [ 44.517109] audit: type=1334 audit(1658859870.268:59): prog-id=19 op=LOAD [ 44.622031] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 [ 44.624321] Mem abort info: [ 44.625049] ESR = 0x0000000096000004 [ 44.625935] EC = 0x25: DABT (current EL), IL = 32 bits [ 44.627182] SET = 0, FnV = 0 [ 44.627930] EA = 0, S1PTW = 0 [ 44.628684] FSC = 0x04: level 0 translation fault [ 44.629788] Data abort info: [ 44.630474] ISV = 0, ISS = 0x00000004 [ 44.631362] CM = 0, WnR = 0 [ 44.632041] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000100ab5000 [ 44.633494] [0000000000000010] pgd=0000000000000000, p4d=0000000000000000 [ 44.635202] Internal error: Oops: 96000004 [#1] SMP [ 44.636452] Modules linked in: xfs crct10dif_ce ghash_ce virtio_blk virtio_console virtio_mmio qemu_fw_cfg [ 44.638713] CPU: 2 PID: 1 Comm: systemd Not tainted 5.19.0-rc7 #1 [ 44.640164] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 44.641799] pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 44.643404] pc : ftrace_set_filter_ip+0x24/0xa0 [ 44.644659] lr : bpf_trampoline_update.constprop.0+0x428/0x4a0 [ 44.646118] sp : ffff80000803b9f0 [ 44.646950] x29: ffff80000803b9f0 x28: ffff0b5d80364400 x27: ffff80000803bb48 [ 44.648721] x26: ffff8000085ad000 x25: ffff0b5d809d2400 x24: 0000000000000000 [ 44.650493] x23: 00000000ffffffed x22: ffff0b5dd7ea0900 x21: 0000000000000000 [ 44.652279] x20: 0000000000000000 x19: 0000000000000000 x18: ffffffffffffffff [ 44.654067] x17: 0000000000000000 x16: 0000000000000000 x15: ffffffffffffffff [ 44.655787] x14: ffff0b5d809d2498 x13: ffff0b5d809d2432 x12: 0000000005f5e100 [ 44.657535] x11: abcc77118461cefd x10: 000000000000005f x9 : ffffa7219cb5b190 [ 44.659254] x8 : ffffa7219c8e0000 x7 : 0000000000000000 x6 : ffffa7219db075e0 [ 44.661066] x5 : ffffa7219d3130e0 x4 : ffffa7219cab9da0 x3 : 0000000000000000 [ 44.662837] x2 : 0000000000000000 x1 : ffffa7219cb7a5c0 x0 : 0000000000000000 [ 44.664675] Call trace: [ 44.665274] ftrace_set_filter_ip+0x24/0xa0 [ 44.666327] bpf_trampoline_update.constprop.0+0x428/0x4a0 [ 44.667696] __bpf_trampoline_link_prog+0xcc/0x1c0 [ 44.668834] bpf_trampoline_link_prog+0x40/0x64 [ 44.669919] bpf_tracing_prog_attach+0x120/0x490 [ 44.671011] link_create+0xe0/0x2b0 [ 44.671869] __sys_bpf+0x484/0xd30 [ 44.672706] __arm64_sys_bpf+0x30/0x40 [ 44.673678] invoke_syscall+0x78/0x100 [ 44.674623] el0_svc_common.constprop.0+0x4c/0xf4 [ 44.675783] do_el0_svc+0x38/0x4c [ 44.676624] el0_svc+0x34/0x100 [ 44.677429] el0t_64_sync_handler+0x11c/0x150 [ 44.678532] el0t_64_sync+0x190/0x194 [ 44.679439] Code: 2a0203f4 f90013f5 2a0303f5 f9001fe1 (f9400800) [ 44.680959] ---[ end trace 0000000000000000 ]--- [ 44.682111] Kernel panic - not syncing: Oops: Fatal exception [ 44.683488] SMP: stopping secondary CPUs [ 44.684551] Kernel Offset: 0x2721948e0000 from 0xffff800008000000 [ 44.686095] PHYS_OFFSET: 0xfffff4a380000000 [ 44.687144] CPU features: 0x010,00022811,19001080 [ 44.688308] Memory Limit: none [ 44.689082] ---[ end Kernel panic - not syncing: Oops: Fatal exception ]--- It's caused by a NULL tr->fops passed to ftrace_set_filter_ip(). tr->fops is initialized to NULL and is assigned to an allocated memory address if CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS is enabled. Since there is no direct call on arm64 yet, the config can't be enabled. To fix it, call ftrace_set_filter_ip() only if tr->fops is not NULL. Fixes: 00963a2e75a8 ("bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)") Reported-by: Bruno Goncalves <bgoncalv@redhat.com> Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Bruno Goncalves <bgoncalv@redhat.com> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20220728114048.3540461-1-xukuohai@huaweicloud.com
2022-07-29bpf: Fix test_progs -j error with fentry/fexit testsSong Liu1-1/+1
When multiple threads are attaching/detaching fentry/fexit programs to the same trampoline, we may call register_fentry on the same trampoline twice: register_fentry(), unregister_fentry(), then register_fentry again. This causes ftrace_set_filter_ip() for the same ip on tr->fops twice, which leaves duplicated ip in tr->fops. The extra ip is not cleaned up properly on unregister and thus causes failures with further register in register_ftrace_direct_multi(): register_ftrace_direct_multi() { ... for (i = 0; i < size; i++) { hlist_for_each_entry(entry, &hash->buckets[i], hlist) { if (ftrace_find_rec_direct(entry->ip)) goto out_unlock; } } ... } This can be triggered with parallel fentry/fexit tests with test_progs: ./test_progs -t fentry,fexit -j Fix this by resetting tr->fops in ftrace_set_filter_ip(), so that there will never be duplicated entries in tr->fops. Fixes: 00963a2e75a8 ("bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)") Reported-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220729194106.1207472-1-song@kernel.org
2022-07-22bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)Song Liu1-17/+141
When tracing a function with IPMODIFY ftrace_ops (livepatch), the bpf trampoline must follow the instruction pointer saved on stack. This needs extra handling for bpf trampolines with BPF_TRAMP_F_CALL_ORIG flag. Implement bpf_tramp_ftrace_ops_func and use it for the ftrace_ops used by BPF trampoline. This enables tracing functions with livepatch. This also requires moving bpf trampoline to *_ftrace_direct_mult APIs. Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/all/20220602193706.2607681-2-song@kernel.org/ Link: https://lore.kernel.org/bpf/20220720002126.803253-5-song@kernel.org
2022-07-19bpf: fix lsm_cgroup build errors on esoteric configsStanislav Fomichev1-1/+1
This particular ones is about having the following: CONFIG_BPF_LSM=y # CONFIG_CGROUP_BPF is not set Also, add __maybe_unused to the args for the !CONFIG_NET cases. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/r/20220714185404.3647772-1-sdf@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-11bpf: Remove is_valid_bpf_tramp_flags()Xu Kuohai1-0/+3
Before generating bpf trampoline, x86 calls is_valid_bpf_tramp_flags() to check the input flags. This check is architecture independent. So, to be consistent with x86, arm64 should also do this check before generating bpf trampoline. However, the BPF_TRAMP_F_XXX flags are not used by user code and the flags argument is almost constant at compile time, so this run time check is a bit redundant. Remove is_valid_bpf_tramp_flags() and add some comments to the usage of BPF_TRAMP_F_XXX flags, as suggested by Alexei. Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20220711150823.2128542-2-xukuohai@huawei.com
2022-06-29bpf: minimize number of allocated lsm slots per programStanislav Fomichev1-0/+1
Previous patch adds 1:1 mapping between all 211 LSM hooks and bpf_cgroup program array. Instead of reserving a slot per possible hook, reserve 10 slots per cgroup for lsm programs. Those slots are dynamically allocated on demand and reclaimed. struct cgroup_bpf { struct bpf_prog_array * effective[33]; /* 0 264 */ /* --- cacheline 4 boundary (256 bytes) was 8 bytes ago --- */ struct hlist_head progs[33]; /* 264 264 */ /* --- cacheline 8 boundary (512 bytes) was 16 bytes ago --- */ u8 flags[33]; /* 528 33 */ /* XXX 7 bytes hole, try to pack */ struct list_head storages; /* 568 16 */ /* --- cacheline 9 boundary (576 bytes) was 8 bytes ago --- */ struct bpf_prog_array * inactive; /* 584 8 */ struct percpu_ref refcnt; /* 592 16 */ struct work_struct release_work; /* 608 72 */ /* size: 680, cachelines: 11, members: 7 */ /* sum members: 673, holes: 1, sum holes: 7 */ /* last cacheline: 40 bytes */ }; Reviewed-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20220628174314.1216643-5-sdf@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29bpf: per-cgroup lsm flavorStanislav Fomichev1-0/+198
Allow attaching to lsm hooks in the cgroup context. Attaching to per-cgroup LSM works exactly like attaching to other per-cgroup hooks. New BPF_LSM_CGROUP is added to trigger new mode; the actual lsm hook we attach to is signaled via existing attach_btf_id. For the hooks that have 'struct socket' or 'struct sock' as its first argument, we use the cgroup associated with that socket. For the rest, we use 'current' cgroup (this is all on default hierarchy == v2 only). Note that for some hooks that work on 'struct sock' we still take the cgroup from 'current' because some of them work on the socket that hasn't been properly initialized yet. Behind the scenes, we allocate a shim program that is attached to the trampoline and runs cgroup effective BPF programs array. This shim has some rudimentary ref counting and can be shared between several programs attaching to the same lsm hook from different cgroups. Note that this patch bloats cgroup size because we add 211 cgroup_bpf_attach_type(s) for simplicity sake. This will be addressed in the subsequent patch. Also note that we only add non-sleepable flavor for now. To enable sleepable use-cases, bpf_prog_run_array_cg has to grab trace rcu, shim programs have to be freed via trace rcu, cgroup_bpf.effective should be also trace-rcu-managed + maybe some other changes that I'm not aware of. Reviewed-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20220628174314.1216643-4-sdf@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29bpf: add bpf_func_t and trampoline helpersStanislav Fomichev1-30/+33
I'll be adding lsm cgroup specific helpers that grab trampoline mutex. No functional changes. Reviewed-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20220628174314.1216643-2-sdf@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-05-11bpf: Fix potential array overflow in bpf_trampoline_get_progs()Yuntao Wang1-6/+12
The cnt value in the 'cnt >= BPF_MAX_TRAMP_PROGS' check does not include BPF_TRAMP_MODIFY_RETURN bpf programs, so the number of the attached BPF_TRAMP_MODIFY_RETURN bpf programs in a trampoline can exceed BPF_MAX_TRAMP_PROGS. When this happens, the assignment '*progs++ = aux->prog' in bpf_trampoline_get_progs() will cause progs array overflow as the progs field in the bpf_tramp_progs struct can only hold at most BPF_MAX_TRAMP_PROGS bpf programs. Fixes: 88fd9e5352fe ("bpf: Refactor trampoline update code") Signed-off-by: Yuntao Wang <ytcoode@gmail.com> Link: https://lore.kernel.org/r/20220430130803.210624-1-ytcoode@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-05-10bpf, x86: Attach a cookie to fentry/fexit/fmod_ret/lsm.Kui-Feng Lee1-2/+5
Pass a cookie along with BPF_LINK_CREATE requests. Add a bpf_cookie field to struct bpf_tracing_link to attach a cookie. The cookie of a bpf_tracing_link is available by calling bpf_get_attach_cookie when running the BPF program of the attached link. The value of a cookie will be set at bpf_tramp_run_ctx by the trampoline of the link. Signed-off-by: Kui-Feng Lee <kuifeng@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220510205923.3206889-4-kuifeng@fb.com
2022-05-10bpf, x86: Create bpf_tramp_run_ctx on the caller thread's stackKui-Feng Lee1-4/+16
BPF trampolines will create a bpf_tramp_run_ctx, a bpf_run_ctx, on stacks and set/reset the current bpf_run_ctx before/after calling a bpf_prog. Signed-off-by: Kui-Feng Lee <kuifeng@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220510205923.3206889-3-kuifeng@fb.com
2022-05-10bpf, x86: Generate trampolines from bpf_tramp_linksKui-Feng Lee1-32/+41
Replace struct bpf_tramp_progs with struct bpf_tramp_links to collect struct bpf_tramp_link(s) for a trampoline. struct bpf_tramp_link extends bpf_link to act as a linked list node. arch_prepare_bpf_trampoline() accepts a struct bpf_tramp_links to collects all bpf_tramp_link(s) that a trampoline should call. Change BPF trampoline and bpf_struct_ops to pass bpf_tramp_links instead of bpf_tramp_progs. Signed-off-by: Kui-Feng Lee <kuifeng@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220510205923.3206889-2-kuifeng@fb.com
2022-03-27Merge tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-16/+4
Pull x86 CET-IBT (Control-Flow-Integrity) support from Peter Zijlstra: "Add support for Intel CET-IBT, available since Tigerlake (11th gen), which is a coarse grained, hardware based, forward edge Control-Flow-Integrity mechanism where any indirect CALL/JMP must target an ENDBR instruction or suffer #CP. Additionally, since Alderlake (12th gen)/Sapphire-Rapids, speculation is limited to 2 instructions (and typically fewer) on branch targets not starting with ENDBR. CET-IBT also limits speculation of the next sequential instruction after the indirect CALL/JMP [1]. CET-IBT is fundamentally incompatible with retpolines, but provides, as described above, speculation limits itself" [1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html * tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) kvm/emulate: Fix SETcc emulation for ENDBR x86/Kconfig: Only allow CONFIG_X86_KERNEL_IBT with ld.lld >= 14.0.0 x86/Kconfig: Only enable CONFIG_CC_HAS_IBT for clang >= 14.0.0 kbuild: Fixup the IBT kbuild changes x86/Kconfig: Do not allow CONFIG_X86_X32_ABI=y with llvm-objcopy x86: Remove toolchain check for X32 ABI capability x86/alternative: Use .ibt_endbr_seal to seal indirect calls objtool: Find unused ENDBR instructions objtool: Validate IBT assumptions objtool: Add IBT/ENDBR decoding objtool: Read the NOENDBR annotation x86: Annotate idtentry_df() x86,objtool: Move the ASM_REACHABLE annotation to objtool.h x86: Annotate call_on_stack() objtool: Rework ASM_REACHABLE x86: Mark __invalid_creds() __noreturn exit: Mark do_group_exit() __noreturn x86: Mark stop_this_cpu() __noreturn objtool: Ignore extra-symbol code objtool: Rename --duplicate to --lto ...
2022-03-15x86/ibt,ftrace: Search for __fentry__ locationPeter Zijlstra1-16/+4
Currently a lot of ftrace code assumes __fentry__ is at sym+0. However with Intel IBT enabled the first instruction of a function will most likely be ENDBR. Change ftrace_location() to not only return the __fentry__ location when called for the __fentry__ location, but also when called for the sym+0 location. Then audit/update all callsites of this function to consistently use these new semantics. Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20220308154318.227581603@infradead.org
2022-02-23bpf: Cleanup commentsTom Rix1-1/+1
Add leading space to spdx tag Use // for spdx c file comment Replacements resereved to reserved inbetween to in between everytime to every time intutivie to intuitive currenct to current encontered to encountered referenceing to referencing upto to up to exectuted to executed Signed-off-by: Tom Rix <trix@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20220220184055.3608317-1-trix@redhat.com
2022-02-09Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski1-3/+3
Daniel Borkmann says: ==================== pull-request: bpf-next 2022-02-09 We've added 126 non-merge commits during the last 16 day(s) which contain a total of 201 files changed, 4049 insertions(+), 2215 deletions(-). The main changes are: 1) Add custom BPF allocator for JITs that pack multiple programs into a huge page to reduce iTLB pressure, from Song Liu. 2) Add __user tagging support in vmlinux BTF and utilize it from BPF verifier when generating loads, from Yonghong Song. 3) Add per-socket fast path check guarding from cgroup/BPF overhead when used by only some sockets, from Pavel Begunkov. 4) Continued libbpf deprecation work of APIs/features and removal of their usage from samples, selftests, libbpf & bpftool, from Andrii Nakryiko and various others. 5) Improve BPF instruction set documentation by adding byte swap instructions and cleaning up load/store section, from Christoph Hellwig. 6) Switch BPF preload infra to light skeleton and remove libbpf dependency from it, from Alexei Starovoitov. 7) Fix architecture-agnostic macros in libbpf for accessing syscall arguments from BPF progs for non-x86 architectures, from Ilya Leoshkevich. 8) Rework port members in struct bpf_sk_lookup and struct bpf_sock to be of 16-bit field with anonymous zero padding, from Jakub Sitnicki. 9) Add new bpf_copy_from_user_task() helper to read memory from a different task than current. Add ability to create sleepable BPF iterator progs, from Kenny Yu. 10) Implement XSK batching for ice's zero-copy driver used by AF_XDP and utilize TX batching API from XSK buffer pool, from Maciej Fijalkowski. 11) Generate temporary netns names for BPF selftests to avoid naming collisions, from Hangbin Liu. 12) Implement bpf_core_types_are_compat() with limited recursion for in-kernel usage, from Matteo Croce. 13) Simplify pahole version detection and finally enable CONFIG_DEBUG_INFO_DWARF5 to be selected with CONFIG_DEBUG_INFO_BTF, from Nathan Chancellor. 14) Misc minor fixes to libbpf and selftests from various folks. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (126 commits) selftests/bpf: Cover 4-byte load from remote_port in bpf_sk_lookup bpf: Make remote_port field in struct bpf_sk_lookup 16-bit wide libbpf: Fix compilation warning due to mismatched printf format selftests/bpf: Test BPF_KPROBE_SYSCALL macro libbpf: Add BPF_KPROBE_SYSCALL macro libbpf: Fix accessing the first syscall argument on s390 libbpf: Fix accessing the first syscall argument on arm64 libbpf: Allow overriding PT_REGS_PARM1{_CORE}_SYSCALL selftests/bpf: Skip test_bpf_syscall_macro's syscall_arg1 on arm64 and s390 libbpf: Fix accessing syscall arguments on riscv libbpf: Fix riscv register names libbpf: Fix accessing syscall arguments on powerpc selftests/bpf: Use PT_REGS_SYSCALL_REGS in bpf_syscall_macro libbpf: Add PT_REGS_SYSCALL_REGS macro selftests/bpf: Fix an endianness issue in bpf_syscall_macro test bpf: Fix bpf_prog_pack build HPAGE_PMD_SIZE bpf: Fix leftover header->pages in sparc and powerpc code. libbpf: Fix signedness bug in btf_dump_array_data() selftests/bpf: Do not export subtest as standalone test bpf, x86_64: Fail gracefully on bpf_jit_binary_pack_finalize failures ... ==================== Link: https://lore.kernel.org/r/20220209210050.8425-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-07bpf: Use bytes instead of pages for bpf_jit_[charge|uncharge]_modmemSong Liu1-3/+3
This enables sub-page memory charge and allocation. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220204185742.271030-3-song@kernel.org
2022-01-25bpf: Fix possible race in inc_misses_counterHe Fengqing1-2/+3
It seems inc_misses_counter() suffers from same issue fixed in the commit d979617aa84d ("bpf: Fixes possible race in update_prog_stats() for 32bit arches"): As it can run while interrupts are enabled, it could be re-entered and the u64_stats syncp could be mangled. Fixes: 9ed9e9ba2337 ("bpf: Count the number of times recursion was prevented") Signed-off-by: He Fengqing <hefengqing@huawei.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/r/20220122102936.1219518-1-hefengqing@huawei.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-12-13bpf: Add get_func_[arg|ret|arg_cnt] helpersJiri Olsa1-0/+8
Adding following helpers for tracing programs: Get n-th argument of the traced function: long bpf_get_func_arg(void *ctx, u32 n, u64 *value) Get return value of the traced function: long bpf_get_func_ret(void *ctx, u64 *value) Get arguments count of the traced function: long bpf_get_func_arg_cnt(void *ctx) The trampoline now stores number of arguments on ctx-8 address, so it's easy to verify argument index and find return value argument's position. Moving function ip address on the trampoline stack behind the number of functions arguments, so it's now stored on ctx-16 address if it's needed. All helpers above are inlined by verifier. Also bit unrelated small change - using newly added function bpf_prog_has_trampoline in check_get_func_ip. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211208193245.172141-5-jolsa@kernel.org
2021-10-27bpf: Use u64_stats_t in struct bpf_prog_statsEric Dumazet1-3/+3
Commit 316580b69d0a ("u64_stats: provide u64_stats_t type") fixed possible load/store tearing on 64bit arches. For instance the following C code stats->nsecs += sched_clock() - start; Could be rightfully implemented like this by a compiler, confusing concurrent readers a lot: stats->nsecs += sched_clock(); // arbitrary delay stats->nsecs -= start; Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211026214133.3114279-4-eric.dumazet@gmail.com
2021-10-27bpf: Fixes possible race in update_prog_stats() for 32bit archesEric Dumazet1-2/+4
It seems update_prog_stats() suffers from same issue fixed in the prior patch: As it can run while interrupts are enabled, it could be re-entered and the u64_stats syncp could be mangled. Fixes: fec56f5890d9 ("bpf: Introduce BPF trampoline") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211026214133.3114279-3-eric.dumazet@gmail.com
2021-09-13bpf: Introduce helper bpf_get_branch_snapshotSong Liu1-1/+2
Introduce bpf_get_branch_snapshot(), which allows tracing pogram to get branch trace from hardware (e.g. Intel LBR). To use the feature, the user need to create perf_event with proper branch_record filtering on each cpu, and then calls bpf_get_branch_snapshot in the bpf function. On Intel CPUs, VLBR event (raw event 0x1b00) can be use for this. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210910183352.3151445-3-songliubraving@fb.com