[PATCH 2/5] bpf: Do per-instruction state dumping in verifier when log_level > 1.

[PATCH 2/5] bpf: Do per-instruction state dumping in verifier when log_level > 1.

[David Miller]

If log_level > 1, do a state dump every instruction and emit it in
a more compact way (without a leading newline).

This will facilitate more sophisticated test cases which inspect the
verifier log for register state.

Signed-off-by: David S. Miller <davem@davemloft.net>
---
 kernel/bpf/verifier.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 56230ff..e1effce 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2932,8 +2932,12 @@ static int do_check(struct bpf_verifier_env *env)
 			goto process_bpf_exit;
 		}
 
-		if (log_level && do_print_state) {
-			verbose("\nfrom %d to %d:", prev_insn_idx, insn_idx);
+		if (log_level > 1 || (log_level && do_print_state)) {
+			if (log_level > 1)
+				verbose("%d:", insn_idx);
+			else
+				verbose("\nfrom %d to %d:",
+					prev_insn_idx, insn_idx);
 			print_verifier_state(&env->cur_state);
 			do_print_state = false;
 		}
-- 
2.1.2.532.g19b5d50

Re: [PATCH 2/5] bpf: Do per-instruction state dumping in verifier when log_level > 1.

[Daniel Borkmann]

On 05/10/2017 09:09 PM, David Miller wrote:
>
> If log_level > 1, do a state dump every instruction and emit it in
> a more compact way (without a leading newline).
>
> This will facilitate more sophisticated test cases which inspect the
> verifier log for register state.
>
> Signed-off-by: David S. Miller <davem@davemloft.net>

Acked-by: Daniel Borkmann <daniel@iogearbox.net>