bpf: add upper complexity limit to verifier log

Given the limit could potentially get further adjustments in the
future, add it to the log so it becomes obvious what the current
limit is w/o having to check the source first. This may also be
helpful for debugging complexity related issues on kernels that
backport from upstream.

Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Alexei Starovoitov <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 5eeb200e82c4378395d8ff319c2d2ffe7ef89a2c..caae4955fbdb786eb7bb6ea15821c70f50aaab40 100644 (file)
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4810,7 +4810,8 @@ process_bpf_exit:
                insn_idx++;
        }
 
-       verbose(env, "processed %d insns, stack depth ", insn_processed);
+       verbose(env, "processed %d insns (limit %d), stack depth ",
+               insn_processed, BPF_COMPLEXITY_LIMIT_INSNS);
        for (i = 0; i < env->subprog_cnt + 1; i++) {
                u32 depth = env->subprog_stack_depth[i];