[PATCH v2 bpf-next 5/5] selftests/bpf: Fix potential NULL pointer dereference in strscpy call

[Feng Yang]

From: Feng Yang <yangf...@kylinos.cn>

In test__start_subtest_with_desc, if strdup fails or an empty name is passed,
the function returns early. Later, worker_main_send_subtests copies the name 
via strscpy,
which leads to a NULL pointer dereference.

Signed-off-by: Feng Yang <yangf...@kylinos.cn>
---
 tools/testing/selftests/bpf/test_progs.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/test_progs.c 
b/tools/testing/selftests/bpf/test_progs.c
index ea9c887201ae..ab88268db9e2 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -1882,7 +1882,8 @@ static int worker_main_send_subtests(int sock, struct 
test_state *state)
 
                msg.subtest_done.num = i;
 
-               strscpy(msg.subtest_done.name, subtest_state->name, 
MAX_SUBTEST_NAME);
+               const char *name = subtest_state->name ? : "";
+               strscpy(msg.subtest_done.name, name, MAX_SUBTEST_NAME);
 
                msg.subtest_done.error_cnt = subtest_state->error_cnt;
                msg.subtest_done.skipped = subtest_state->skipped;
-- 
2.43.0