diff options
| -rw-r--r-- | include/linux/bpf_verifier.h | 1 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 18 |
2 files changed, 16 insertions, 3 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 242d0b1a0772..b847e1ccd10f 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -406,6 +406,7 @@ struct bpf_subprog_info { bool has_tail_call; bool tail_call_reachable; bool has_ld_abs; + bool is_async_cb; }; /* single container for all structs diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index ab06256bf6c8..344ee67265cc 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3709,6 +3709,8 @@ process_func: continue_func: subprog_end = subprog[idx + 1].start; for (; i < subprog_end; i++) { + int next_insn; + if (!bpf_pseudo_call(insn + i) && !bpf_pseudo_func(insn + i)) continue; /* remember insn and function to return to */ @@ -3716,13 +3718,22 @@ continue_func: ret_prog[frame] = idx; /* find the callee */ - i = i + insn[i].imm + 1; - idx = find_subprog(env, i); + next_insn = i + insn[i].imm + 1; + idx = find_subprog(env, next_insn); if (idx < 0) { WARN_ONCE(1, "verifier bug. No program starts at insn %d\n", - i); + next_insn); return -EFAULT; } + if (subprog[idx].is_async_cb) { + if (subprog[idx].has_tail_call) { + verbose(env, "verifier bug. subprog has tail_call and async cb\n"); + return -EFAULT; + } + /* async callbacks don't increase bpf prog stack size */ + continue; + } + i = next_insn; if (subprog[idx].has_tail_call) tail_call_reachable = true; @@ -5761,6 +5772,7 @@ static int __check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn struct bpf_verifier_state *async_cb; /* there is no real recursion here. timer callbacks are async */ + env->subprog_info[subprog].is_async_cb = true; async_cb = push_async_cb(env, env->subprog_info[subprog].start, *insn_idx, subprog); if (!async_cb) |