diff options
Diffstat (limited to 'kernel/bpf/syscall.c')
| -rw-r--r-- | kernel/bpf/syscall.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index fd495190115e..941ca06d9dfa 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2648,14 +2648,25 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, * target_btf_id using the link_create API. * * - if tgt_prog == NULL when this function was called using the old - * raw_tracepoint_open API, and we need a target from prog->aux - * - * The combination of no saved target in prog->aux, and no target - * specified on load is illegal, and we reject that here. + * raw_tracepoint_open API, and we need a target from prog->aux + * + * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program + * was detached and is going for re-attachment. */ if (!prog->aux->dst_trampoline && !tgt_prog) { - err = -ENOENT; - goto out_unlock; + /* + * Allow re-attach for TRACING and LSM programs. If it's + * currently linked, bpf_trampoline_link_prog will fail. + * EXT programs need to specify tgt_prog_fd, so they + * re-attach in separate code path. + */ + if (prog->type != BPF_PROG_TYPE_TRACING && + prog->type != BPF_PROG_TYPE_LSM) { + err = -EINVAL; + goto out_unlock; + } + btf_id = prog->aux->attach_btf_id; + key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); } if (!prog->aux->dst_trampoline || |