diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/core.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 833442661742..037d67cf5fb1 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -3262,4 +3262,37 @@ int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char * return 0; } +struct walk_stack_ctx { + struct bpf_prog *prog; +}; + +static bool find_from_stack_cb(void *cookie, u64 ip, u64 sp, u64 bp) +{ + struct walk_stack_ctx *ctxp = cookie; + struct bpf_prog *prog; + + /* + * The RCU read lock is held to safely traverse the latch tree, but we + * don't need its protection when accessing the prog, since it has an + * active stack frame on the current stack trace, and won't disappear. + */ + rcu_read_lock(); + prog = bpf_prog_ksym_find(ip); + rcu_read_unlock(); + if (!prog) + return true; + if (bpf_is_subprog(prog)) + return true; + ctxp->prog = prog; + return false; +} + +struct bpf_prog *bpf_prog_find_from_stack(void) +{ + struct walk_stack_ctx ctx = {}; + + arch_bpf_stack_walk(find_from_stack_cb, &ctx); + return ctx.prog; +} + #endif |