diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 5fb3c610fa96a5dba4f5d82fff0c816f91da3a37..f63afdc43beccf2c16cfbb13ae17bc8972c1bb18 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -169,7 +169,9 @@ u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5); u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); void bpf_fd_array_map_clear(struct bpf_map *map); bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp); + const struct bpf_func_proto *bpf_get_trace_printk_proto(void); +const struct bpf_func_proto *bpf_get_event_output_proto(void); #ifdef CONFIG_BPF_SYSCALL DECLARE_PER_CPU(int, bpf_prog_active); diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 70eda5aeb304281cb3462f25445886111726f78a..b7b0fb1292e745394d8c61db2fc2f50e53604f8f 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -347,6 +347,10 @@ enum bpf_func_id { #define BPF_F_ZERO_CSUM_TX (1ULL << 1) #define BPF_F_DONT_FRAGMENT (1ULL << 2) +/* BPF_FUNC_perf_event_output flags. */ +#define BPF_F_INDEX_MASK 0xffffffffULL +#define BPF_F_CURRENT_CPU BPF_F_INDEX_MASK + /* user accessible mirror of in-kernel sk_buff. * new fields can only be added to the end of this structure */ diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index be0abf669ced3b5b228a10d5ad6ac99576fae0f7..e4248fe79513093b00dc33a039ed540aef34a1b9 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -764,14 +764,21 @@ const struct bpf_func_proto bpf_map_delete_elem_proto __weak; const struct bpf_func_proto bpf_get_prandom_u32_proto __weak; const struct bpf_func_proto bpf_get_smp_processor_id_proto __weak; const struct bpf_func_proto bpf_ktime_get_ns_proto __weak; + const struct bpf_func_proto bpf_get_current_pid_tgid_proto __weak; const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak; const struct bpf_func_proto bpf_get_current_comm_proto __weak; + const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void) { return NULL; } +const struct bpf_func_proto * __weak bpf_get_event_output_proto(void) +{ + return NULL; +} + /* Always built-in helper functions. */ const struct bpf_func_proto bpf_tail_call_proto = { .func = NULL, diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index f389629dade7a7a685fc907655f8e8aaca21d5f5..780bcbe1d4de33bbb24d2328b231bb056bc641b5 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -225,11 +225,12 @@ static const struct bpf_func_proto bpf_perf_event_read_proto = { .arg2_type = ARG_ANYTHING, }; -static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 index, u64 r4, u64 size) +static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size) { struct pt_regs *regs = (struct pt_regs *) (long) r1; struct bpf_map *map = (struct bpf_map *) (long) r2; struct bpf_array *array = container_of(map, struct bpf_array, map); + u64 index = flags & BPF_F_INDEX_MASK; void *data = (void *) (long) r4; struct perf_sample_data sample_data; struct perf_event *event; @@ -239,6 +240,10 @@ static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 index, u64 r4, u64 size) .data = data, }; + if (unlikely(flags & ~(BPF_F_INDEX_MASK))) + return -EINVAL; + if (index == BPF_F_CURRENT_CPU) + index = raw_smp_processor_id(); if (unlikely(index >= array->map.max_entries)) return -E2BIG; @@ -272,6 +277,33 @@ static const struct bpf_func_proto bpf_perf_event_output_proto = { .arg5_type = ARG_CONST_STACK_SIZE, }; +static DEFINE_PER_CPU(struct pt_regs, bpf_pt_regs); + +static u64 bpf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size) +{ + struct pt_regs *regs = this_cpu_ptr(&bpf_pt_regs); + + perf_fetch_caller_regs(regs); + + return bpf_perf_event_output((long)regs, r2, flags, r4, size); +} + +static const struct bpf_func_proto bpf_event_output_proto = { + .func = bpf_event_output, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_CONST_MAP_PTR, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_STACK, + .arg5_type = ARG_CONST_STACK_SIZE, +}; + +const struct bpf_func_proto *bpf_get_event_output_proto(void) +{ + return &bpf_event_output_proto; +} + static const struct bpf_func_proto *tracing_func_proto(enum bpf_func_id func_id) { switch (func_id) { diff --git a/net/core/filter.c b/net/core/filter.c index 5d2ac2b9d1c4fcce377ed90a2cd861c04eb7f613..218e5de8c402b9fac28083fbf1400590022be514 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2039,6 +2039,8 @@ tc_cls_act_func_proto(enum bpf_func_id func_id) return &bpf_redirect_proto; case BPF_FUNC_get_route_realm: return &bpf_get_route_realm_proto; + case BPF_FUNC_perf_event_output: + return bpf_get_event_output_proto(); default: return sk_filter_func_proto(func_id); }