On 6/21/22 9:01 AM, Jörn-Thorben Hinz wrote:
test_sock_fields__detach() got called with a null pointer here when one
of the CHECKs or ASSERTs up to the test_sock_fields__open_and_load()
call resulted in a jump to the "done" label.
A skeletons *__detach() is not safe to call with a null pointer, though.
This led to a segfault.
Go the easy route and only call test_sock_fields__destroy() which is
null-pointer safe and includes detaching.
Came across this while looking[1] to introduce the usage of
bpf_tcp_helpers.h (included in progs/test_sock_fields.c) together with
vmlinux.h.
[1] https://lore.kernel.org/bpf/629bc069dd807d7ac646f836e9dca28bbc1108e2.camel@xxxxxxxxxxxxxxxxxxxx/
Fixes: 8f50f16ff39d ("selftests/bpf: Extend verifier and bpf_sock tests for dst_port loads")
Signed-off-by: Jörn-Thorben Hinz <jthinz@xxxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/bpf/prog_tests/sock_fields.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/sock_fields.c b/tools/testing/selftests/bpf/prog_tests/sock_fields.c
index 9d211b5c22c4..7d23166c77af 100644
--- a/tools/testing/selftests/bpf/prog_tests/sock_fields.c
+++ b/tools/testing/selftests/bpf/prog_tests/sock_fields.c
@@ -394,7 +394,6 @@ void serial_test_sock_fields(void)
test();
done:
- test_sock_fields__detach(skel);
test_sock_fields__destroy(skel);
if (child_cg_fd >= 0)
close(child_cg_fd);
Great catch! I think we have similar detach & destroy pattern in a number
of places in selftests.
Should we rather just move the label, like:
diff --git a/tools/testing/selftests/bpf/prog_tests/sock_fields.c b/tools/testing/selftests/bpf/prog_tests/sock_fields.c
index 9d211b5c22c4..e8a947241e37 100644
--- a/tools/testing/selftests/bpf/prog_tests/sock_fields.c
+++ b/tools/testing/selftests/bpf/prog_tests/sock_fields.c
@@ -393,8 +393,8 @@ void serial_test_sock_fields(void)
test();
-done:
test_sock_fields__detach(skel);
+done:
test_sock_fields__destroy(skel);
if (child_cg_fd >= 0)
close(child_cg_fd);
