[PATCH bpf] selftests/bpf: Fix resource leak in serial_test_wq on attach failure

[Kery Qi]

When wq__attach() fails, serial_test_wq() returns early without calling
wq__destroy(), leaking the skeleton resources allocated by
wq__open_and_load(). This causes ASAN leak reports in selftests runs.

Fix this by jumping to a common clean_up label that calls wq__destroy()
on all exit paths after successful open_and_load.

Note that the early return after wq__open_and_load() failure is correct
and doesn't need fixing, since that function returns NULL on failure
(after internally cleaning up any partial allocations).

Fixes: 8290dba51910 ("selftests/bpf: wq: add bpf_wq_start() checks")
Signed-off-by: Kery Qi <qikeyu2...@gmail.com>
---
 tools/testing/selftests/bpf/prog_tests/wq.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/wq.c 
b/tools/testing/selftests/bpf/prog_tests/wq.c
index 15c67d23128b..84831eecc935 100644
--- a/tools/testing/selftests/bpf/prog_tests/wq.c
+++ b/tools/testing/selftests/bpf/prog_tests/wq.c
@@ -16,12 +16,12 @@ void serial_test_wq(void)
        /* re-run the success test to check if the timer was actually executed 
*/
 
        wq_skel = wq__open_and_load();
-       if (!ASSERT_OK_PTR(wq_skel, "wq_skel_load"))
+       if (!ASSERT_OK_PTR(wq_skel, "wq__open_and_load"))
                return;
 
        err = wq__attach(wq_skel);
        if (!ASSERT_OK(err, "wq_attach"))
-               return;
+               goto clean_up;
 
        prog_fd = bpf_program__fd(wq_skel->progs.test_syscall_array_sleepable);
        err = bpf_prog_test_run_opts(prog_fd, &topts);
@@ -31,6 +31,7 @@ void serial_test_wq(void)
        usleep(50); /* 10 usecs should be enough, but give it extra */
 
        ASSERT_EQ(wq_skel->bss->ok_sleepable, (1 << 1), "ok_sleepable");
+clean_up:
        wq__destroy(wq_skel);
 }
 
-- 
2.34.1