Re: [PATCH bpf] selftests/bpf: add missing pointer dereference for map stacktrace fixup

[Prashant Bhole]

On 12/7/2018 1:14 PM, Stanislav Fomichev wrote:

I get a segfault without it, other fixups always do dereference, and
without dereference I don't understand how it can ever work.

Fixes: 7c85c448e7d74 ("selftests/bpf: test_verifier, check
bpf_map_lookup_elem access in bpf prog")

Signed-off-by: Stanislav Fomichev <s...@google.com>
---
  tools/testing/selftests/bpf/test_verifier.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/test_verifier.c 
b/tools/testing/selftests/bpf/test_verifier.c
index df6f751cc1e8..d23929a1985d 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -14166,7 +14166,7 @@ static void do_test_fixup(struct bpf_test *test, enum 
bpf_map_type prog_type,
                do {
                        prog[*fixup_map_stacktrace].imm = map_fds[12];
                        fixup_map_stacktrace++;
-               } while (fixup_map_stacktrace);
+               } while (*fixup_map_stacktrace);
        }
  }

It was my mistake. Thanks for the fix!

-Prashant