diff options
| author | Andrii Nakryiko <andrii@kernel.org> | 2024-01-25 12:55:05 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2024-01-29 12:34:13 -0800 |
| commit | 9eea8fafe33eb70868f6ace2fc1e17c4ff5539c3 (patch) | |
| tree | 504fe883aa1bf4cbb27a7cbf85152d3cd2d93c65 /tools/lib | |
| parent | 0e6d0a9d2348b64df74239e859fa9d6e86cdcdef (diff) | |
libbpf: fix __arg_ctx type enforcement for perf_event programs
Adjust PERF_EVENT type enforcement around __arg_ctx to match exactly
what kernel is doing.
Fixes: 76ec90a996e3 ("libbpf: warn on unexpected __arg_ctx type when rewriting BTF")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240125205510.3642094-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 41ab7a21f868..db65ea59a05a 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -33,6 +33,7 @@ #include <linux/filter.h> #include <linux/limits.h> #include <linux/perf_event.h> +#include <linux/bpf_perf_event.h> #include <linux/ring_buffer.h> #include <sys/epoll.h> #include <sys/ioctl.h> @@ -6339,6 +6340,14 @@ static struct { /* all other program types don't have "named" context structs */ }; +/* forward declarations for arch-specific underlying types of bpf_user_pt_regs_t typedef, + * for below __builtin_types_compatible_p() checks; + * with this approach we don't need any extra arch-specific #ifdef guards + */ +struct pt_regs; +struct user_pt_regs; +struct user_regs_struct; + static bool need_func_arg_type_fixup(const struct btf *btf, const struct bpf_program *prog, const char *subprog_name, int arg_idx, int arg_type_id, const char *ctx_name) @@ -6379,11 +6388,21 @@ static bool need_func_arg_type_fixup(const struct btf *btf, const struct bpf_pro /* special cases */ switch (prog->type) { case BPF_PROG_TYPE_KPROBE: - case BPF_PROG_TYPE_PERF_EVENT: /* `struct pt_regs *` is expected, but we need to fix up */ if (btf_is_struct(t) && strcmp(tname, "pt_regs") == 0) return true; break; + case BPF_PROG_TYPE_PERF_EVENT: + if (__builtin_types_compatible_p(bpf_user_pt_regs_t, struct pt_regs) && + btf_is_struct(t) && strcmp(tname, "pt_regs") == 0) + return 0; + if (__builtin_types_compatible_p(bpf_user_pt_regs_t, struct user_pt_regs) && + btf_is_struct(t) && strcmp(tname, "user_pt_regs") == 0) + return 0; + if (__builtin_types_compatible_p(bpf_user_pt_regs_t, struct user_regs_struct) && + btf_is_struct(t) && strcmp(tname, "user_regs_struct") == 0) + return 0; + break; case BPF_PROG_TYPE_RAW_TRACEPOINT: case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: /* allow u64* as ctx */ |