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2023-11-01bpf: Add __bpf_kfunc_{start,end}_defs macrosDave Marchevsky
BPF kfuncs are meant to be called from BPF programs. Accordingly, most kfuncs are not called from anywhere in the kernel, which the -Wmissing-prototypes warning is unhappy about. We've peppered __diag_ignore_all("-Wmissing-prototypes", ... everywhere kfuncs are defined in the codebase to suppress this warning. This patch adds two macros meant to bound one or many kfunc definitions. All existing kfunc definitions which use these __diag calls to suppress -Wmissing-prototypes are migrated to use the newly-introduced macros. A new __diag_ignore_all - for "-Wmissing-declarations" - is added to the __bpf_kfunc_start_defs macro based on feedback from Andrii on an earlier version of this patch [0] and another recent mailing list thread [1]. In the future we might need to ignore different warnings or do other kfunc-specific things. This change will make it easier to make such modifications for all kfunc defs. [0]: https://lore.kernel.org/bpf/CAEf4BzaE5dRWtK6RPLnjTW-MW9sx9K3Fn6uwqCTChK2Dcb1Xig@mail.gmail.com/ [1]: https://lore.kernel.org/bpf/ZT+2qCc%2FaXep0%2FLf@krava/ Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Suggested-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Cc: Jiri Olsa <olsajiri@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: David Vernet <void@manifault.com> Acked-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20231031215625.2343848-1-davemarchevsky@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-25bpf: Count missed stats in trace_call_bpfJiri Olsa
Increase misses stats in case bpf array execution is skipped because of recursion check in trace_call_bpf. Adding bpf_prog_inc_misses_counters that increase misses counts for all bpf programs in bpf_prog_array. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Song Liu <song@kernel.org> Reviewed-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20230920213145.1941596-5-jolsa@kernel.org
2023-09-25bpf: Add missed value to kprobe perf link infoJiri Olsa
Add missed value to kprobe attached through perf link info to hold the stats of missed kprobe handler execution. The kprobe's missed counter gets incremented when kprobe handler is not executed due to another kprobe running on the same cpu. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230920213145.1941596-4-jolsa@kernel.org
2023-09-25bpf: Add missed value to kprobe_multi link infoJiri Olsa
Add missed value to kprobe_multi link info to hold the stats of missed kprobe_multi probe. The missed counter gets incremented when fprobe fails the recursion check or there's no rethook available for return probe. In either case the attached bpf program is not executed. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Song Liu <song@kernel.org> Reviewed-by: Song Liu <song@kernel.org> Acked-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/bpf/20230920213145.1941596-3-jolsa@kernel.org
2023-09-25bpf: Count stats for kprobe_multi programsJiri Olsa
Adding support to gather missed stats for kprobe_multi programs due to bpf_prog_active protection. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Song Liu <song@kernel.org> Reviewed-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20230920213145.1941596-2-jolsa@kernel.org
2023-09-15bpf: Fix uprobe_multi get_pid_task error pathJiri Olsa
Dan reported Smatch static checker warning due to missing error value set in uprobe multi link's get_pid_task error path. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/bpf/c5ffa7c0-6b06-40d5-aca2-63833b5cd9af@moroto.mountain/ Signed-off-by: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230915101420.1193800-1-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-08bpf: Add override check to kprobe multi link attachJiri Olsa
Currently the multi_kprobe link attach does not check error injection list for programs with bpf_override_return helper and allows them to attach anywhere. Adding the missing check. Fixes: 0dcac2725406 ("bpf: Add multi kprobe link") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/bpf/20230907200652.926951-1-jolsa@kernel.org
2023-08-21bpf: Add bpf_get_func_ip helper support for uprobe linkJiri Olsa
Adding support for bpf_get_func_ip helper being called from ebpf program attached by uprobe_multi link. It returns the ip of the uprobe. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230809083440.3209381-7-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-08-21bpf: Add pid filter support for uprobe_multi linkJiri Olsa
Adding support to specify pid for uprobe_multi link and the uprobes are created only for task with given pid value. Using the consumer.filter filter callback for that, so the task gets filtered during the uprobe installation. We still need to check the task during runtime in the uprobe handler, because the handler could get executed if there's another system wide consumer on the same uprobe (thanks Oleg for the insight). Cc: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230809083440.3209381-6-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-08-21bpf: Add cookies support for uprobe_multi linkJiri Olsa
Adding support to specify cookies array for uprobe_multi link. The cookies array share indexes and length with other uprobe_multi arrays (offsets/ref_ctr_offsets). The cookies[i] value defines cookie for i-the uprobe and will be returned by bpf_get_attach_cookie helper when called from ebpf program hooked to that specific uprobe. Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230809083440.3209381-5-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-08-21bpf: Add multi uprobe linkJiri Olsa
Adding new multi uprobe link that allows to attach bpf program to multiple uprobes. Uprobes to attach are specified via new link_create uprobe_multi union: struct { __aligned_u64 path; __aligned_u64 offsets; __aligned_u64 ref_ctr_offsets; __u32 cnt; __u32 flags; } uprobe_multi; Uprobes are defined for single binary specified in path and multiple calling sites specified in offsets array with optional reference counters specified in ref_ctr_offsets array. All specified arrays have length of 'cnt'. The 'flags' supports single bit for now that marks the uprobe as return probe. Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230809083440.3209381-4-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-08-07bpf: Add support for bpf_get_func_ip helper for uprobe programJiri Olsa
Adding support for bpf_get_func_ip helper for uprobe program to return probed address for both uprobe and return uprobe. We discussed this in [1] and agreed that uprobe can have special use of bpf_get_func_ip helper that differs from kprobe. The kprobe bpf_get_func_ip returns: - address of the function if probe is attach on function entry for both kprobe and return kprobe - 0 if the probe is not attach on function entry The uprobe bpf_get_func_ip returns: - address of the probe for both uprobe and return uprobe The reason for this semantic change is that kernel can't really tell if the probe user space address is function entry. The uprobe program is actually kprobe type program attached as uprobe. One of the consequences of this design is that uprobes do not have its own set of helpers, but share them with kprobes. As we need different functionality for bpf_get_func_ip helper for uprobe, I'm adding the bool value to the bpf_trace_run_ctx, so the helper can detect that it's executed in uprobe context and call specific code. The is_uprobe bool is set as true in bpf_prog_run_array_sleepable, which is currently used only for executing bpf programs in uprobe. Renaming bpf_prog_run_array_sleepable to bpf_prog_run_array_uprobe to address that it's only used for uprobes and that it sets the run_ctx.is_uprobe as suggested by Yafang Shao. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> [1] https://lore.kernel.org/bpf/CAEf4BzZ=xLVkG5eurEuvLU79wAMtwho7ReR+XJAgwhFF4M-7Cg@mail.gmail.com/ Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Viktor Malik <vmalik@redhat.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230807085956.2344866-2-jolsa@kernel.org Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-08-03Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Martin KaFai Lau says: ==================== pull-request: bpf-next 2023-08-03 We've added 54 non-merge commits during the last 10 day(s) which contain a total of 84 files changed, 4026 insertions(+), 562 deletions(-). The main changes are: 1) Add SO_REUSEPORT support for TC bpf_sk_assign from Lorenz Bauer, Daniel Borkmann 2) Support new insns from cpu v4 from Yonghong Song 3) Non-atomically allocate freelist during prefill from YiFei Zhu 4) Support defragmenting IPv(4|6) packets in BPF from Daniel Xu 5) Add tracepoint to xdp attaching failure from Leon Hwang 6) struct netdev_rx_queue and xdp.h reshuffling to reduce rebuild time from Jakub Kicinski * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits) net: invert the netdevice.h vs xdp.h dependency net: move struct netdev_rx_queue out of netdevice.h eth: add missing xdp.h includes in drivers selftests/bpf: Add testcase for xdp attaching failure tracepoint bpf, xdp: Add tracepoint to xdp attaching failure selftests/bpf: fix static assert compilation issue for test_cls_*.c bpf: fix bpf_probe_read_kernel prototype mismatch riscv, bpf: Adapt bpf trampoline to optimized riscv ftrace framework libbpf: fix typos in Makefile tracing: bpf: use struct trace_entry in struct syscall_tp_t bpf, devmap: Remove unused dtab field from bpf_dtab_netdev bpf, cpumap: Remove unused cmap field from bpf_cpu_map_entry netfilter: bpf: Only define get_proto_defrag_hook() if necessary bpf: Fix an array-index-out-of-bounds issue in disasm.c net: remove duplicate INDIRECT_CALLABLE_DECLARE of udp[6]_ehashfn docs/bpf: Fix malformed documentation bpf: selftests: Add defrag selftests bpf: selftests: Support custom type and proto for client sockets bpf: selftests: Support not connecting client socket netfilter: bpf: Support BPF_F_NETFILTER_IP_DEFRAG in netfilter link ... ==================== Link: https://lore.kernel.org/r/20230803174845.825419-1-martin.lau@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. Conflicts: net/dsa/port.c 9945c1fb03a3 ("net: dsa: fix older DSA drivers using phylink") a88dd7538461 ("net: dsa: remove legacy_pre_march2020 detection") https://lore.kernel.org/all/20230731102254.2c9868ca@canb.auug.org.au/ net/xdp/xsk.c 3c5b4d69c358 ("net: annotate data-races around sk->sk_mark") b7f72a30e9ac ("xsk: introduce wrappers and helpers for supporting multi-buffer in Tx path") https://lore.kernel.org/all/20230731102631.39988412@canb.auug.org.au/ drivers/net/ethernet/broadcom/bnxt/bnxt.c 37b61cda9c16 ("bnxt: don't handle XDP in netpoll") 2b56b3d99241 ("eth: bnxt: handle invalid Tx completions more gracefully") https://lore.kernel.org/all/20230801101708.1dc7faac@canb.auug.org.au/ Adjacent changes: drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_fs.c 62da08331f1a ("net/mlx5e: Set proper IPsec source port in L4 selector") fbd517549c32 ("net/mlx5e: Add function to get IPsec offload namespace") drivers/net/ethernet/sfc/selftest.c 55c1528f9b97 ("sfc: fix field-spanning memcpy in selftest") ae9d445cd41f ("sfc: Miscellaneous comment removals") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-02bpf: fix bpf_probe_read_kernel prototype mismatchArnd Bergmann
bpf_probe_read_kernel() has a __weak definition in core.c and another definition with an incompatible prototype in kernel/trace/bpf_trace.c, when CONFIG_BPF_EVENTS is enabled. Since the two are incompatible, there cannot be a shared declaration in a header file, but the lack of a prototype causes a W=1 warning: kernel/bpf/core.c:1638:12: error: no previous prototype for 'bpf_probe_read_kernel' [-Werror=missing-prototypes] On 32-bit architectures, the local prototype u64 __weak bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr) passes arguments in other registers as the one in bpf_trace.c BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size, const void *, unsafe_ptr) which uses 64-bit arguments in pairs of registers. As both versions of the function are fairly simple and only really differ in one line, just move them into a header file as an inline function that does not add any overhead for the bpf_trace.c callers and actually avoids a function call for the other one. Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/ac25cb0f-b804-1649-3afb-1dc6138c2716@iogearbox.net/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230801111449.185301-1-arnd@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-25bpf: Disable preemption in bpf_event_outputJiri Olsa
We received report [1] of kernel crash, which is caused by using nesting protection without disabled preemption. The bpf_event_output can be called by programs executed by bpf_prog_run_array_cg function that disabled migration but keeps preemption enabled. This can cause task to be preempted by another one inside the nesting protection and lead eventually to two tasks using same perf_sample_data buffer and cause crashes like: BUG: kernel NULL pointer dereference, address: 0000000000000001 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page ... ? perf_output_sample+0x12a/0x9a0 ? finish_task_switch.isra.0+0x81/0x280 ? perf_event_output+0x66/0xa0 ? bpf_event_output+0x13a/0x190 ? bpf_event_output_data+0x22/0x40 ? bpf_prog_dfc84bbde731b257_cil_sock4_connect+0x40a/0xacb ? xa_load+0x87/0xe0 ? __cgroup_bpf_run_filter_sock_addr+0xc1/0x1a0 ? release_sock+0x3e/0x90 ? sk_setsockopt+0x1a1/0x12f0 ? udp_pre_connect+0x36/0x50 ? inet_dgram_connect+0x93/0xa0 ? __sys_connect+0xb4/0xe0 ? udp_setsockopt+0x27/0x40 ? __pfx_udp_push_pending_frames+0x10/0x10 ? __sys_setsockopt+0xdf/0x1a0 ? __x64_sys_connect+0xf/0x20 ? do_syscall_64+0x3a/0x90 ? entry_SYSCALL_64_after_hwframe+0x72/0xdc Fixing this by disabling preemption in bpf_event_output. [1] https://github.com/cilium/cilium/issues/26756 Cc: stable@vger.kernel.org Reported-by: Oleg "livelace" Popov <o.popov@livelace.ru> Closes: https://github.com/cilium/cilium/issues/26756 Fixes: 2a916f2f546c ("bpf: Use migrate_disable/enable in array macros and cgroup/lirc code.") Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230725084206.580930-3-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-25bpf: Disable preemption in bpf_perf_event_outputJiri Olsa
The nesting protection in bpf_perf_event_output relies on disabled preemption, which is guaranteed for kprobes and tracepoints. However bpf_perf_event_output can be also called from uprobes context through bpf_prog_run_array_sleepable function which disables migration, but keeps preemption enabled. This can cause task to be preempted by another one inside the nesting protection and lead eventually to two tasks using same perf_sample_data buffer and cause crashes like: kernel tried to execute NX-protected page - exploit attempt? (uid: 0) BUG: unable to handle page fault for address: ffffffff82be3eea ... Call Trace: ? __die+0x1f/0x70 ? page_fault_oops+0x176/0x4d0 ? exc_page_fault+0x132/0x230 ? asm_exc_page_fault+0x22/0x30 ? perf_output_sample+0x12b/0x910 ? perf_event_output+0xd0/0x1d0 ? bpf_perf_event_output+0x162/0x1d0 ? bpf_prog_c6271286d9a4c938_krava1+0x76/0x87 ? __uprobe_perf_func+0x12b/0x540 ? uprobe_dispatcher+0x2c4/0x430 ? uprobe_notify_resume+0x2da/0xce0 ? atomic_notifier_call_chain+0x7b/0x110 ? exit_to_user_mode_prepare+0x13e/0x290 ? irqentry_exit_to_user_mode+0x5/0x30 ? asm_exc_int3+0x35/0x40 Fixing this by disabling preemption in bpf_perf_event_output. Cc: stable@vger.kernel.org Fixes: 8c7dcb84e3b7 ("bpf: implement sleepable uprobes by chaining gps") Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230725084206.580930-2-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-13Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Alexei Starovoitov says: ==================== pull-request: bpf-next 2023-07-13 We've added 67 non-merge commits during the last 15 day(s) which contain a total of 106 files changed, 4444 insertions(+), 619 deletions(-). The main changes are: 1) Fix bpftool build in presence of stale vmlinux.h, from Alexander Lobakin. 2) Introduce bpf_me_mcache_free_rcu() and fix OOM under stress, from Alexei Starovoitov. 3) Teach verifier actual bounds of bpf_get_smp_processor_id() and fix perf+libbpf issue related to custom section handling, from Andrii Nakryiko. 4) Introduce bpf map element count, from Anton Protopopov. 5) Check skb ownership against full socket, from Kui-Feng Lee. 6) Support for up to 12 arguments in BPF trampoline, from Menglong Dong. 7) Export rcu_request_urgent_qs_task, from Paul E. McKenney. 8) Fix BTF walking of unions, from Yafang Shao. 9) Extend link_info for kprobe_multi and perf_event links, from Yafang Shao. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (67 commits) selftests/bpf: Add selftest for PTR_UNTRUSTED bpf: Fix an error in verifying a field in a union selftests/bpf: Add selftests for nested_trust bpf: Fix an error around PTR_UNTRUSTED selftests/bpf: add testcase for TRACING with 6+ arguments bpf, x86: allow function arguments up to 12 for TRACING bpf, x86: save/restore regs with BPF_DW size bpftool: Use "fallthrough;" keyword instead of comments bpf: Add object leak check. bpf: Convert bpf_cpumask to bpf_mem_cache_free_rcu. bpf: Introduce bpf_mem_free_rcu() similar to kfree_rcu(). selftests/bpf: Improve test coverage of bpf_mem_alloc. rcu: Export rcu_request_urgent_qs_task() bpf: Allow reuse from waiting_for_gp_ttrace list. bpf: Add a hint to allocated objects. bpf: Change bpf_mem_cache draining process. bpf: Further refactor alloc_bulk(). bpf: Factor out inc/dec of active flag into helpers. bpf: Refactor alloc_bulk(). bpf: Let free_all() return the number of freed elements. ... ==================== Link: https://lore.kernel.org/r/20230714020910.80794-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-11bpf: Support ->fill_link_info for perf_eventYafang Shao
By introducing support for ->fill_link_info to the perf_event link, users gain the ability to inspect it using `bpftool link show`. While the current approach involves accessing this information via `bpftool perf show`, consolidating link information for all link types in one place offers greater convenience. Additionally, this patch extends support to the generic perf event, which is not currently accommodated by `bpftool perf show`. While only the perf type and config are exposed to userspace, other attributes such as sample_period and sample_freq are ignored. It's important to note that if kptr_restrict is not permitted, the probed address will not be exposed, maintaining security measures. A new enum bpf_perf_event_type is introduced to help the user understand which struct is relevant. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230709025630.3735-9-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-11bpf: Clear the probe_addr for uprobeYafang Shao
To avoid returning uninitialized or random values when querying the file descriptor (fd) and accessing probe_addr, it is necessary to clear the variable prior to its use. Fixes: 41bdc4b40ed6 ("bpf: introduce bpf subcommand BPF_TASK_FD_QUERY") Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230709025630.3735-6-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-11bpf: Support ->fill_link_info for kprobe_multiYafang Shao
With the addition of support for fill_link_info to the kprobe_multi link, users will gain the ability to inspect it conveniently using the `bpftool link show`. This enhancement provides valuable information to the user, including the count of probed functions and their respective addresses. It's important to note that if the kptr_restrict setting is not permitted, the probed address will not be exposed, ensuring security. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230709025630.3735-2-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-30Merge tag 'probes-v6.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: - fprobe: Pass return address to the fprobe entry/exit callbacks so that the callbacks don't need to analyze pt_regs/stack to find the function return address. - kprobe events: cleanup usage of TPARG_FL_FENTRY and TPARG_FL_RETURN flags so that those are not set at once. - fprobe events: - Add a new fprobe events for tracing arbitrary function entry and exit as a trace event. - Add a new tracepoint events for tracing raw tracepoint as a trace event. This allows user to trace non user-exposed tracepoints. - Move eprobe's event parser code into probe event common file. - Introduce BTF (BPF type format) support to kernel probe (kprobe, fprobe and tracepoint probe) events so that user can specify traced function arguments by name. This also applies the type of argument when fetching the argument. - Introduce '$arg*' wildcard support if BTF is available. This expands the '$arg*' meta argument to all function argument automatically. - Check the return value types by BTF. If the function returns 'void', '$retval' is rejected. - Add some selftest script for fprobe events, tracepoint events and BTF support. - Update documentation about the fprobe events. - Some fixes for above features, document and selftests. - selftests for ftrace (in addition to the new fprobe events): - Add a test case for multiple consecutive probes in a function which checks if ftrace based kprobe, optimized kprobe and normal kprobe can be defined in the same target function. - Add a test case for optimized probe, which checks whether kprobe can be optimized or not. * tag 'probes-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Fix tracepoint event with $arg* to fetch correct argument Documentation: Fix typo of reference file name tracing/probes: Fix to return NULL and keep using current argc selftests/ftrace: Add new test case which checks for optimized probes selftests/ftrace: Add new test case which adds multiple consecutive probes in a function Documentation: tracing/probes: Add fprobe event tracing document selftests/ftrace: Add BTF arguments test cases selftests/ftrace: Add tracepoint probe test case tracing/probes: Add BTF retval type support tracing/probes: Add $arg* meta argument for all function args tracing/probes: Support function parameters if BTF is available tracing/probes: Move event parameter fetching code to common parser tracing/probes: Add tracepoint support on fprobe_events selftests/ftrace: Add fprobe related testcases tracing/probes: Add fprobe events for tracing function entry and exit. tracing/probes: Avoid setting TPARG_FL_FENTRY and TPARG_FL_RETURN fprobe: Pass return address to the handlers
2023-06-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. Conflicts: net/sched/sch_taprio.c d636fc5dd692 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping") dced11ef84fb ("net/sched: taprio: don't overwrite "sch" variable in taprio_dump_class_stats()") net/ipv4/sysctl_net_ipv4.c e209fee4118f ("net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294") ccce324dabfe ("tcp: make the first N SYN RTO backoffs linear") https://lore.kernel.org/all/20230605100816.08d41a7b@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-07bpf: Add extra path pointer check to d_path helperJiri Olsa
Anastasios reported crash on stable 5.15 kernel with following BPF attached to lsm hook: SEC("lsm.s/bprm_creds_for_exec") int BPF_PROG(bprm_creds_for_exec, struct linux_binprm *bprm) { struct path *path = &bprm->executable->f_path; char p[128] = { 0 }; bpf_d_path(path, p, 128); return 0; } But bprm->executable can be NULL, so bpf_d_path call will crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI ... RIP: 0010:d_path+0x22/0x280 ... Call Trace: <TASK> bpf_d_path+0x21/0x60 bpf_prog_db9cf176e84498d9_bprm_creds_for_exec+0x94/0x99 bpf_trampoline_6442506293_0+0x55/0x1000 bpf_lsm_bprm_creds_for_exec+0x5/0x10 security_bprm_creds_for_exec+0x29/0x40 bprm_execve+0x1c1/0x900 do_execveat_common.isra.0+0x1af/0x260 __x64_sys_execve+0x32/0x40 It's problem for all stable trees with bpf_d_path helper, which was added in 5.9. This issue is fixed in current bpf code, where we identify and mark trusted pointers, so the above code would fail even to load. For the sake of the stable trees and to workaround potentially broken verifier in the future, adding the code that reads the path object from the passed pointer and verifies it's valid in kernel space. Fixes: 6e22ab9da793 ("bpf: Add d_path helper") Reported-by: Anastasios Papagiannis <tasos.papagiannnis@gmail.com> Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20230606181714.532998-1-jolsa@kernel.org
2023-06-06fprobe: Pass return address to the handlersMasami Hiramatsu (Google)
Pass return address as 'ret_ip' to the fprobe entry and return handlers so that the fprobe user handler can get the reutrn address without analyzing arch-dependent pt_regs. Link: https://lore.kernel.org/all/168507467664.913472.11642316698862778600.stgit@mhiramat.roam.corp.google.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-16Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2023-05-16 We've added 57 non-merge commits during the last 19 day(s) which contain a total of 63 files changed, 3293 insertions(+), 690 deletions(-). The main changes are: 1) Add precision propagation to verifier for subprogs and callbacks, from Andrii Nakryiko. 2) Improve BPF's {g,s}setsockopt() handling with wrong option lengths, from Stanislav Fomichev. 3) Utilize pahole v1.25 for the kernel's BTF generation to filter out inconsistent function prototypes, from Alan Maguire. 4) Various dyn-pointer verifier improvements to relax restrictions, from Daniel Rosenberg. 5) Add a new bpf_task_under_cgroup() kfunc for designated task, from Feng Zhou. 6) Unblock tests for arm64 BPF CI after ftrace supporting direct call, from Florent Revest. 7) Add XDP hint kfunc metadata for RX hash/timestamp for igc, from Jesper Dangaard Brouer. 8) Add several new dyn-pointer kfuncs to ease their usability, from Joanne Koong. 9) Add in-depth LRU internals description and dot function graph, from Joe Stringer. 10) Fix KCSAN report on bpf_lru_list when accessing node->ref, from Martin KaFai Lau. 11) Only dump unprivileged_bpf_disabled log warning upon write, from Kui-Feng Lee. 12) Extend test_progs to directly passing allow/denylist file, from Stephen Veiss. 13) Fix BPF trampoline memleak upon failure attaching to fentry, from Yafang Shao. 14) Fix emitting struct bpf_tcp_sock type in vmlinux BTF, from Yonghong Song. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (57 commits) bpf: Fix memleak due to fentry attach failure bpf: Remove bpf trampoline selector bpf, arm64: Support struct arguments in the BPF trampoline bpftool: JIT limited misreported as negative value on aarch64 bpf: fix calculation of subseq_idx during precision backtracking bpf: Remove anonymous union in bpf_kfunc_call_arg_meta bpf: Document EFAULT changes for sockopt selftests/bpf: Correctly handle optlen > 4096 selftests/bpf: Update EFAULT {g,s}etsockopt selftests bpf: Don't EFAULT for {g,s}setsockopt with wrong optlen libbpf: fix offsetof() and container_of() to work with CO-RE bpf: Address KCSAN report on bpf_lru_list bpf: Add --skip_encoding_btf_inconsistent_proto, --btf_gen_optimized to pahole flags for v1.25 selftests/bpf: Accept mem from dynptr in helper funcs bpf: verifier: Accept dynptr mem as mem in helpers selftests/bpf: Check overflow in optional buffer selftests/bpf: Test allowing NULL buffer in dynptr slice bpf: Allow NULL buffers in bpf_dynptr_slice(_rw) selftests/bpf: Add testcase for bpf_task_under_cgroup bpf: Add bpf_task_under_cgroup() kfunc ... ==================== Link: https://lore.kernel.org/r/20230515225603.27027-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-28Merge tag 'trace-v6.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - User events are finally ready! After lots of collaboration between various parties, we finally locked down on a stable interface for user events that can also work with user space only tracing. This is implemented by telling the kernel (or user space library, but that part is user space only and not part of this patch set), where the variable is that the application uses to know if something is listening to the trace. There's also an interface to tell the kernel about these events, which will show up in the /sys/kernel/tracing/events/user_events/ directory, where it can be enabled. When it's enabled, the kernel will update the variable, to tell the application to start writing to the kernel. See https://lwn.net/Articles/927595/ - Cleaned up the direct trampolines code to simplify arm64 addition of direct trampolines. Direct trampolines use the ftrace interface but instead of jumping to the ftrace trampoline, applications (mostly BPF) can register their own trampoline for performance reasons. - Some updates to the fprobe infrastructure. fprobes are more efficient than kprobes, as it does not need to save all the registers that kprobes on ftrace do. More work needs to be done before the fprobes will be exposed as dynamic events. - More updates to references to the obsolete path of /sys/kernel/debug/tracing for the new /sys/kernel/tracing path. - Add a seq_buf_do_printk() helper to seq_bufs, to print a large buffer line by line instead of all at once. There are users in production kernels that have a large data dump that originally used printk() directly, but the data dump was larger than what printk() allowed as a single print. Using seq_buf() to do the printing fixes that. - Add /sys/kernel/tracing/touched_functions that shows all functions that was every traced by ftrace or a direct trampoline. This is used for debugging issues where a traced function could have caused a crash by a bpf program or live patching. - Add a "fields" option that is similar to "raw" but outputs the fields of the events. It's easier to read by humans. - Some minor fixes and clean ups. * tag 'trace-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (41 commits) ring-buffer: Sync IRQ works before buffer destruction tracing: Add missing spaces in trace_print_hex_seq() ring-buffer: Ensure proper resetting of atomic variables in ring_buffer_reset_online_cpus recordmcount: Fix memory leaks in the uwrite function tracing/user_events: Limit max fault-in attempts tracing/user_events: Prevent same address and bit per process tracing/user_events: Ensure bit is cleared on unregister tracing/user_events: Ensure write index cannot be negative seq_buf: Add seq_buf_do_printk() helper tracing: Fix print_fields() for __dyn_loc/__rel_loc tracing/user_events: Set event filter_type from type ring-buffer: Clearly check null ptr returned by rb_set_head_page() tracing: Unbreak user events tracing/user_events: Use print_format_fields() for trace output tracing/user_events: Align structs with tabs for readability tracing/user_events: Limit global user_event count tracing/user_events: Charge event allocs to cgroups tracing/user_events: Update documentation for ABI tracing/user_events: Use write ABI in example tracing/user_events: Add ABI self-test ...
2023-04-27bpf: Add bpf_dynptr_sizeJoanne Koong
bpf_dynptr_size returns the number of usable bytes in a dynptr. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20230420071414.570108-4-joannelkoong@gmail.com
2023-03-28fprobe: Skip exit_handler if entry_handler returns !0Masami Hiramatsu (Google)
Skip hooking function return and calling exit_handler if the entry_handler() returns !0. Link: https://lkml.kernel.org/r/167526699798.433354.10998365726830117303.stgit@mhiramat.roam.corp.google.com Cc: Florent Revest <revest@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-03-28fprobe: Pass entry_data to handlersMasami Hiramatsu (Google)
Pass the private entry_data to the entry and exit handlers so that they can share the context data, something like saved function arguments etc. User must specify the private entry_data size by @entry_data_size field before registering the fprobe. Link: https://lkml.kernel.org/r/167526696173.433354.17408372048319432574.stgit@mhiramat.roam.corp.google.com Cc: Florent Revest <revest@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-03-02bpf: Make bpf_get_current_[ancestor_]cgroup_id() available for all program typesTejun Heo
These helpers are safe to call from any context and there's no reason to restrict access to them. Remove them from bpf_trace and filter lists and add to bpf_base_func_proto() under perfmon_capable(). v2: After consulting with Andrii, relocated in bpf_base_func_proto() so that they require bpf_capable() but not perfomon_capable() as it doesn't read from or affect others on the system. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/ZAD8QyoszMZiTzBY@slm.duckdns.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-21Merge tag 'net-next-6.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
2023-02-20Merge tag 'perf-core-2023-02-20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: - Optimize perf_sample_data layout - Prepare sample data handling for BPF integration - Update the x86 PMU driver for Intel Meteor Lake - Restructure the x86 uncore code to fix a SPR (Sapphire Rapids) discovery breakage - Fix the x86 Zhaoxin PMU driver - Cleanups * tag 'perf-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) perf/x86/intel/uncore: Add Meteor Lake support x86/perf/zhaoxin: Add stepping check for ZXC perf/x86/intel/ds: Fix the conversion from TSC to perf time perf/x86/uncore: Don't WARN_ON_ONCE() for a broken discovery table perf/x86/uncore: Add a quirk for UPI on SPR perf/x86/uncore: Ignore broken units in discovery table perf/x86/uncore: Fix potential NULL pointer in uncore_get_alias_name perf/x86/uncore: Factor out uncore_device_to_die() perf/core: Call perf_prepare_sample() before running BPF perf/core: Introduce perf_prepare_header() perf/core: Do not pass header for sample ID init perf/core: Set data->sample_flags in perf_prepare_sample() perf/core: Add perf_sample_save_brstack() helper perf/core: Add perf_sample_save_raw_data() helper perf/core: Add perf_sample_save_callchain() helper perf/core: Save the dynamic parts of sample data size x86/kprobes: Use switch-case for 0xFF opcodes in prepare_emulation perf/core: Change the layout of perf_sample_data perf/x86/msr: Add Meteor Lake support perf/x86/cstate: Add Meteor Lake support ...
2023-02-10Daniel Borkmann says:Jakub Kicinski
==================== pull-request: bpf-next 2023-02-11 We've added 96 non-merge commits during the last 14 day(s) which contain a total of 152 files changed, 4884 insertions(+), 962 deletions(-). There is a minor conflict in drivers/net/ethernet/intel/ice/ice_main.c between commit 5b246e533d01 ("ice: split probe into smaller functions") from the net-next tree and commit 66c0e13ad236 ("drivers: net: turn on XDP features") from the bpf-next tree. Remove the hunk given ice_cfg_netdev() is otherwise there a 2nd time, and add XDP features to the existing ice_cfg_netdev() one: [...] ice_set_netdev_features(netdev); netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT | NETDEV_XDP_ACT_XSK_ZEROCOPY; ice_set_ops(netdev); [...] Stephen's merge conflict mail: https://lore.kernel.org/bpf/20230207101951.21a114fa@canb.auug.org.au/ The main changes are: 1) Add support for BPF trampoline on s390x which finally allows to remove many test cases from the BPF CI's DENYLIST.s390x, from Ilya Leoshkevich. 2) Add multi-buffer XDP support to ice driver, from Maciej Fijalkowski. 3) Add capability to export the XDP features supported by the NIC. Along with that, add a XDP compliance test tool, from Lorenzo Bianconi & Marek Majtyka. 4) Add __bpf_kfunc tag for marking kernel functions as kfuncs, from David Vernet. 5) Add a deep dive documentation about the verifier's register liveness tracking algorithm, from Eduard Zingerman. 6) Fix and follow-up cleanups for resolve_btfids to be compiled as a host program to avoid cross compile issues, from Jiri Olsa & Ian Rogers. 7) Batch of fixes to the BPF selftest for xdp_hw_metadata which resulted when testing on different NICs, from Jesper Dangaard Brouer. 8) Fix libbpf to better detect kernel version code on Debian, from Hao Xiang. 9) Extend libbpf to add an option for when the perf buffer should wake up, from Jon Doron. 10) Follow-up fix on xdp_metadata selftest to just consume on TX completion, from Stanislav Fomichev. 11) Extend the kfuncs.rst document with description on kfunc lifecycle & stability expectations, from David Vernet. 12) Fix bpftool prog profile to skip attaching to offline CPUs, from Tonghao Zhang. ==================== Link: https://lore.kernel.org/r/20230211002037.8489-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
net/core/gro.c 7d2c89b32587 ("skb: Do mix page pool and page referenced frags in GRO") b1a78b9b9886 ("net: add support for ipv4 big tcp") https://lore.kernel.org/all/20230203094454.5766f160@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-02bpf: Add __bpf_kfunc tag to all kfuncsDavid Vernet
Now that we have the __bpf_kfunc tag, we should use add it to all existing kfuncs to ensure that they'll never be elided in LTO builds. Signed-off-by: David Vernet <void@manifault.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20230201173016.342758-4-void@manifault.com
2023-01-28Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== bpf-next 2023-01-28 We've added 124 non-merge commits during the last 22 day(s) which contain a total of 124 files changed, 6386 insertions(+), 1827 deletions(-). The main changes are: 1) Implement XDP hints via kfuncs with initial support for RX hash and timestamp metadata kfuncs, from Stanislav Fomichev and Toke Høiland-Jørgensen. Measurements on overhead: https://lore.kernel.org/bpf/875yellcx6.fsf@toke.dk 2) Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case, from Andrii Nakryiko. 3) Significantly reduce the search time for module symbols by livepatch and BPF, from Jiri Olsa and Zhen Lei. 4) Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals, from David Vernet. 5) Fix several issues in the dynptr processing such as stack slot liveness propagation, missing checks for PTR_TO_STACK variable offset, etc, from Kumar Kartikeya Dwivedi. 6) Various performance improvements, fixes, and introduction of more than just one XDP program to XSK selftests, from Magnus Karlsson. 7) Big batch to BPF samples to reduce deprecated functionality, from Daniel T. Lee. 8) Enable struct_ops programs to be sleepable in verifier, from David Vernet. 9) Reduce pr_warn() noise on BTF mismatches when they are expected under the CONFIG_MODULE_ALLOW_BTF_MISMATCH config anyway, from Connor O'Brien. 10) Describe modulo and division by zero behavior of the BPF runtime in BPF's instruction specification document, from Dave Thaler. 11) Several improvements to libbpf API documentation in libbpf.h, from Grant Seltzer. 12) Improve resolve_btfids header dependencies related to subcmd and add proper support for HOSTCC, from Ian Rogers. 13) Add ipip6 and ip6ip decapsulation support for bpf_skb_adjust_room() helper along with BPF selftests, from Ziyang Xuan. 14) Simplify the parsing logic of structure parameters for BPF trampoline in the x86-64 JIT compiler, from Pu Lehui. 15) Get BTF working for kernels with CONFIG_RUST enabled by excluding Rust compilation units with pahole, from Martin Rodriguez Reboredo. 16) Get bpf_setsockopt() working for kTLS on top of TCP sockets, from Kui-Feng Lee. 17) Disable stack protection for BPF objects in bpftool given BPF backends don't support it, from Holger Hoffstätte. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (124 commits) selftest/bpf: Make crashes more debuggable in test_progs libbpf: Add documentation to map pinning API functions libbpf: Fix malformed documentation formatting selftests/bpf: Properly enable hwtstamp in xdp_hw_metadata selftests/bpf: Calls bpf_setsockopt() on a ktls enabled socket. bpf: Check the protocol of a sock to agree the calls to bpf_setsockopt(). bpf/selftests: Verify struct_ops prog sleepable behavior bpf: Pass const struct bpf_prog * to .check_member libbpf: Support sleepable struct_ops.s section bpf: Allow BPF_PROG_TYPE_STRUCT_OPS programs to be sleepable selftests/bpf: Fix vmtest static compilation error tools/resolve_btfids: Alter how HOSTCC is forced tools/resolve_btfids: Install subcmd headers bpf/docs: Document the nocast aliasing behavior of ___init bpf/docs: Document how nested trusted fields may be defined bpf/docs: Document cpumask kfuncs in a new file selftests/bpf: Add selftest suite for cpumask kfuncs selftests/bpf: Add nested trust selftests suite bpf: Enable cpumasks to be queried and used as kptrs bpf: Disallow NULLable pointers for trusted kfuncs ... ==================== Link: https://lore.kernel.org/r/20230128004827.21371-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
drivers/net/ipa/ipa_interrupt.c drivers/net/ipa/ipa_interrupt.h 9ec9b2a30853 ("net: ipa: disable ipa interrupt during suspend") 8e461e1f092b ("net: ipa: introduce ipa_interrupt_enable()") d50ed3558719 ("net: ipa: enable IPA interrupt handlers separate from registration") https://lore.kernel.org/all/20230119114125.5182c7ab@canb.auug.org.au/ https://lore.kernel.org/all/79e46152-8043-a512-79d9-c3b905462774@tessares.net/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19bpf: Change modules resolving for kprobe multi linkJiri Olsa
We currently use module_kallsyms_on_each_symbol that iterates all modules/symbols and we try to lookup each such address in user provided symbols/addresses to get list of used modules. This fix instead only iterates provided kprobe addresses and calls __module_address on each to get list of used modules. This turned out to be simpler and also bit faster. On my setup with workload (executed 10 times): # test_progs -t kprobe_multi_bench_attach/modules Current code: Performance counter stats for './test.sh' (5 runs): 76,081,161,596 cycles:k ( +- 0.47% ) 18.3867 +- 0.0992 seconds time elapsed ( +- 0.54% ) With the fix: Performance counter stats for './test.sh' (5 runs): 74,079,889,063 cycles:k ( +- 0.04% ) 17.8514 +- 0.0218 seconds time elapsed ( +- 0.12% ) Signed-off-by: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20230116101009.23694-4-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-19livepatch: Improve the search performance of module_kallsyms_on_each_symbol()Zhen Lei
Currently we traverse all symbols of all modules to find the specified function for the specified module. But in reality, we just need to find the given module and then traverse all the symbols in it. Let's add a new parameter 'const char *modname' to function module_kallsyms_on_each_symbol(), then we can compare the module names directly in this function and call hook 'fn' after matching. If 'modname' is NULL, the symbols of all modules are still traversed for compatibility with other usage cases. Phase1: mod1-->mod2..(subsequent modules do not need to be compared) | Phase2: -->f1-->f2-->f3 Assuming that there are m modules, each module has n symbols on average, then the time complexity is reduced from O(m * n) to O(m) + O(n). Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20230116101009.23694-2-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-18bpf: Fix a possible task gone issue with bpf_send_signal[_thread]() helpersYonghong Song
In current bpf_send_signal() and bpf_send_signal_thread() helper implementation, irq_work is used to handle nmi context. Hao Sun reported in [1] that the current task at the entry of the helper might be gone during irq_work callback processing. To fix the issue, a reference is acquired for the current task before enqueuing into the irq_work so that the queued task is still available during irq_work callback processing. [1] https://lore.kernel.org/bpf/20230109074425.12556-1-sunhao.th@gmail.com/ Fixes: 8b401f9ed244 ("bpf: implement bpf_send_signal() helper") Tested-by: Hao Sun <sunhao.th@gmail.com> Reported-by: Hao Sun <sunhao.th@gmail.com> Signed-off-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/r/20230118204815.3331855-1-yhs@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-18perf/core: Add perf_sample_save_raw_data() helperNamhyung Kim
When we save the raw_data to the perf sample data, we need to update the sample flags and the dynamic size. To make sure this is done consistently, add the perf_sample_save_raw_data() helper and convert all call sites. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230118060559.615653-4-namhyung@kernel.org
2023-01-06bpf: Skip task with pid=1 in send_signal_common()Hao Sun
The following kernel panic can be triggered when a task with pid=1 attaches a prog that attempts to send killing signal to itself, also see [1] for more details: Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b CPU: 3 PID: 1 Comm: systemd Not tainted 6.1.0-09652-g59fe41b5255f #148 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x100/0x178 lib/dump_stack.c:106 panic+0x2c4/0x60f kernel/panic.c:275 do_exit.cold+0x63/0xe4 kernel/exit.c:789 do_group_exit+0xd4/0x2a0 kernel/exit.c:950 get_signal+0x2460/0x2600 kernel/signal.c:2858 arch_do_signal_or_restart+0x78/0x5d0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd So skip task with pid=1 in bpf_send_signal_common() to avoid the panic. [1] https://lore.kernel.org/bpf/20221222043507.33037-1-sunhao.th@gmail.com Signed-off-by: Hao Sun <sunhao.th@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20230106084838.12690-1-sunhao.th@gmail.com
2022-12-19bpf: Remove trace_printk_lockJiri Olsa
Both bpf_trace_printk and bpf_trace_vprintk helpers use static buffer guarded with trace_printk_lock spin lock. The spin lock contention causes issues with bpf programs attached to contention_begin tracepoint [1][2]. Andrii suggested we could get rid of the contention by using trylock, but we could actually get rid of the spinlock completely by using percpu buffers the same way as for bin_args in bpf_bprintf_prepare function. Adding new return 'buf' argument to struct bpf_bprintf_data and making bpf_bprintf_prepare to return also the buffer for printk helpers. [1] https://lore.kernel.org/bpf/CACkBjsakT_yWxnSWr4r-0TpPvbKm9-OBmVUhJb7hV3hY8fdCkw@mail.gmail.com/ [2] https://lore.kernel.org/bpf/CACkBjsaCsTovQHFfkqJKto6S4Z8d02ud1D7MPESrHa1cVNNTrw@mail.gmail.com/ Reported-by: Hao Sun <sunhao.th@gmail.com> Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20221215214430.1336195-4-jolsa@kernel.org
2022-12-19bpf: Do cleanup in bpf_bprintf_cleanup only when neededJiri Olsa
Currently we always cleanup/decrement bpf_bprintf_nest_level variable in bpf_bprintf_cleanup if it's > 0. There's possible scenario where this could cause a problem, when bpf_bprintf_prepare does not get bin_args buffer (because num_args is 0) and following bpf_bprintf_cleanup call decrements bpf_bprintf_nest_level variable, like: in task context: bpf_bprintf_prepare(num_args != 0) increments 'bpf_bprintf_nest_level = 1' -> first irq : bpf_bprintf_prepare(num_args == 0) bpf_bprintf_cleanup decrements 'bpf_bprintf_nest_level = 0' -> second irq: bpf_bprintf_prepare(num_args != 0) bpf_bprintf_nest_level = 1 gets same buffer as task context above Adding check to bpf_bprintf_cleanup and doing the real cleanup only if we got bin_args data in the first place. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20221215214430.1336195-3-jolsa@kernel.org
2022-12-19bpf: Add struct for bin_args arg in bpf_bprintf_prepareJiri Olsa
Adding struct bpf_bprintf_data to hold bin_args argument for bpf_bprintf_prepare function. We will add another return argument to bpf_bprintf_prepare and pass the struct to bpf_bprintf_cleanup for proper cleanup in following changes. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20221215214430.1336195-2-jolsa@kernel.org
2022-11-24bpf: Introduce might_sleep field in bpf_func_protoYonghong Song
Introduce bpf_func_proto->might_sleep to indicate a particular helper might sleep. This will make later check whether a helper might be sleepable or not easier. Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/r/20221124053211.2373553-1-yhs@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncsDavid Vernet
Kfuncs currently support specifying the KF_TRUSTED_ARGS flag to signal to the verifier that it should enforce that a BPF program passes it a "safe", trusted pointer. Currently, "safe" means that the pointer is either PTR_TO_CTX, or is refcounted. There may be cases, however, where the kernel passes a BPF program a safe / trusted pointer to an object that the BPF program wishes to use as a kptr, but because the object does not yet have a ref_obj_id from the perspective of the verifier, the program would be unable to pass it to a KF_ACQUIRE | KF_TRUSTED_ARGS kfunc. The solution is to expand the set of pointers that are considered trusted according to KF_TRUSTED_ARGS, so that programs can invoke kfuncs with these pointers without getting rejected by the verifier. There is already a PTR_UNTRUSTED flag that is set in some scenarios, such as when a BPF program reads a kptr directly from a map without performing a bpf_kptr_xchg() call. These pointers of course can and should be rejected by the verifier. Unfortunately, however, PTR_UNTRUSTED does not cover all the cases for safety that need to be addressed to adequately protect kfuncs. Specifically, pointers obtained by a BPF program "walking" a struct are _not_ considered PTR_UNTRUSTED according to BPF. For example, say that we were to add a kfunc called bpf_task_acquire(), with KF_ACQUIRE | KF_TRUSTED_ARGS, to acquire a struct task_struct *. If we only used PTR_UNTRUSTED to signal that a task was unsafe to pass to a kfunc, the verifier would mistakenly allow the following unsafe BPF program to be loaded: SEC("tp_btf/task_newtask") int BPF_PROG(unsafe_acquire_task, struct task_struct *task, u64 clone_flags) { struct task_struct *acquired, *nested; nested = task->last_wakee; /* Would not be rejected by the verifier. */ acquired = bpf_task_acquire(nested); if (!acquired) return 0; bpf_task_release(acquired); return 0; } To address this, this patch defines a new type flag called PTR_TRUSTED which tracks whether a PTR_TO_BTF_ID pointer is safe to pass to a KF_TRUSTED_ARGS kfunc or a BPF helper function. PTR_TRUSTED pointers are passed directly from the kernel as a tracepoint or struct_ops callback argument. Any nested pointer that is obtained from walking a PTR_TRUSTED pointer is no longer PTR_TRUSTED. From the example above, the struct task_struct *task argument is PTR_TRUSTED, but the 'nested' pointer obtained from 'task->last_wakee' is not PTR_TRUSTED. A subsequent patch will add kfuncs for storing a task kfunc as a kptr, and then another patch will add selftests to validate. Signed-off-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20221120051004.3605026-3-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-02Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== bpf-next 2022-11-02 We've added 70 non-merge commits during the last 14 day(s) which contain a total of 96 files changed, 3203 insertions(+), 640 deletions(-). The main changes are: 1) Make cgroup local storage available to non-cgroup attached BPF programs such as tc BPF ones, from Yonghong Song. 2) Avoid unnecessary deadlock detection and failures wrt BPF task storage helpers, from Martin KaFai Lau. 3) Add LLVM disassembler as default library for dumping JITed code in bpftool, from Quentin Monnet. 4) Various kprobe_multi_link fixes related to kernel modules, from Jiri Olsa. 5) Optimize x86-64 JIT with emitting BMI2-based shift instructions, from Jie Meng. 6) Improve BPF verifier's memory type compatibility for map key/value arguments, from Dave Marchevsky. 7) Only create mmap-able data section maps in libbpf when data is exposed via skeletons, from Andrii Nakryiko. 8) Add an autoattach option for bpftool to load all object assets, from Wang Yufen. 9) Various memory handling fixes for libbpf and BPF selftests, from Xu Kuohai. 10) Initial support for BPF selftest's vmtest.sh on arm64, from Manu Bretelle. 11) Improve libbpf's BTF handling to dedup identical structs, from Alan Maguire. 12) Add BPF CI and denylist documentation for BPF selftests, from Daniel Müller. 13) Check BPF cpumap max_entries before doing allocation work, from Florian Lehner. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (70 commits) samples/bpf: Fix typo in README bpf: Remove the obsolte u64_stats_fetch_*_irq() users. bpf: check max_entries before allocating memory bpf: Fix a typo in comment for DFS algorithm bpftool: Fix spelling mistake "disasembler" -> "disassembler" selftests/bpf: Fix bpftool synctypes checking failure selftests/bpf: Panic on hard/soft lockup docs/bpf: Add documentation for new cgroup local storage selftests/bpf: Add test cgrp_local_storage to DENYLIST.s390x selftests/bpf: Add selftests for new cgroup local storage selftests/bpf: Fix test test_libbpf_str/bpf_map_type_str bpftool: Support new cgroup local storage libbpf: Support new cgroup local storage bpf: Implement cgroup storage available to non-cgroup-attached bpf progs bpf: Refactor some inode/task/sk storage functions for reuse bpf: Make struct cgroup btf id global selftests/bpf: Tracing prog can still do lookup under busy lock selftests/bpf: Ensure no task storage failure for bpf_lsm.s prog due to deadlock detection bpf: Add new bpf_task_storage_delete proto with no deadlock detection bpf: bpf_task_storage_delete_recur does lookup first before the deadlock check ... ==================== Link: https://lore.kernel.org/r/20221102062120.5724-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-25bpf: Implement cgroup storage available to non-cgroup-attached bpf progsYonghong Song
Similar to sk/inode/task storage, implement similar cgroup local storage. There already exists a local storage implementation for cgroup-attached bpf programs. See map type BPF_MAP_TYPE_CGROUP_STORAGE and helper bpf_get_local_storage(). But there are use cases such that non-cgroup attached bpf progs wants to access cgroup local storage data. For example, tc egress prog has access to sk and cgroup. It is possible to use sk local storage to emulate cgroup local storage by storing data in socket. But this is a waste as it could be lots of sockets belonging to a particular cgroup. Alternatively, a separate map can be created with cgroup id as the key. But this will introduce additional overhead to manipulate the new map. A cgroup local storage, similar to existing sk/inode/task storage, should help for this use case. The life-cycle of storage is managed with the life-cycle of the cgroup struct. i.e. the storage is destroyed along with the owning cgroup with a call to bpf_cgrp_storage_free() when cgroup itself is deleted. The userspace map operations can be done by using a cgroup fd as a key passed to the lookup, update and delete operations. Typically, the following code is used to get the current cgroup: struct task_struct *task = bpf_get_current_task_btf(); ... task->cgroups->dfl_cgrp ... and in structure task_struct definition: struct task_struct { .... struct css_set __rcu *cgroups; .... } With sleepable program, accessing task->cgroups is not protected by rcu_read_lock. So the current implementation only supports non-sleepable program and supporting sleepable program will be the next step together with adding rcu_read_lock protection for rcu tagged structures. Since map name BPF_MAP_TYPE_CGROUP_STORAGE has been used for old cgroup local storage support, the new map name BPF_MAP_TYPE_CGRP_STORAGE is used for cgroup storage available to non-cgroup-attached bpf programs. The old cgroup storage supports bpf_get_local_storage() helper to get the cgroup data. The new cgroup storage helper bpf_cgrp_storage_get() can provide similar functionality. While old cgroup storage pre-allocates storage memory, the new mechanism can also pre-allocate with a user space bpf_map_update_elem() call to avoid potential run-time memory allocation failure. Therefore, the new cgroup storage can provide all functionality w.r.t. the old one. So in uapi bpf.h, the old BPF_MAP_TYPE_CGROUP_STORAGE is alias to BPF_MAP_TYPE_CGROUP_STORAGE_DEPRECATED to indicate the old cgroup storage can be deprecated since the new one can provide the same functionality. Acked-by: David Vernet <void@manifault.com> Signed-off-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/r/20221026042850.673791-1-yhs@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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