Series comparison

From: Geliang Tang <tanggeliang@kylinos.cn>

Fix the pidfd leak in kselftest_harness.h's __wait_for_test() where
childfd = syscall(__NR_pidfd_open, t->pid, 0) is never closed.

Fixes: 73a3cde97677 ("selftests: harness: Implement test timeouts through pidfd")
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
Hi,

While adding more TLS selftests for MPTCP KTLS development, a segmentation
fault occurred. Debugging revealed that the accept() failure was due to MPTCP
tests requiring over 1024 file descriptors simultaneously. I initially raised
the limit to 4096 in [1], but sashiko noted that the real issue was a pidfd
leak in kselftest_harness.h's __wait_for_test(). Hence, this fix addresses that.

Thanks,
-Geliang

[1]
https://patchwork.kernel.org/project/mptcp/patch/ced184831757eaae9e690f65d799809ed22cae28.1776469069.git.tanggeliang@kylinos.cn/

---
 tools/testing/selftests/kselftest_harness.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index XXXXXXX..XXXXXXX 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -XXX,XX +XXX,XX @@ static void __wait_for_test(struct __test_metadata *t)
 		fprintf(TH_LOG_STREAM,
 			"# %s: unable to wait on child pidfd\n",
 			t->name);
-		return;
+		goto out;
 	} else if (ret == 0) {
 		timed_out = true;
 		/* signal process group */
@@ -XXX,XX +XXX,XX @@ static void __wait_for_test(struct __test_metadata *t)
 		fprintf(TH_LOG_STREAM,
 			"# %s: Failed to wait for PID %d (errno: %d)\n",
 			t->name, t->pid, errno);
-		return;
+		goto out;
 	}
 
 	if (timed_out) {
@@ -XXX,XX +XXX,XX @@ static void __wait_for_test(struct __test_metadata *t)
 			t->name,
 			status);
 	}
+out:
+	close(childfd);
 }
 
 static void test_harness_list_tests(void)
-- 
2.51.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Fix the pidfd leak in kselftest_harness.h's __wait_for_test() where
childfd = syscall(__NR_pidfd_open, t->pid, 0) is never closed.

Fixes: 73a3cde97677 ("selftests: harness: Implement test timeouts through pidfd")
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
v2:
 - move close() directly after poll() as Thomas suggested.

Hi,

Thanks,
-Geliang

[1]
https://patchwork.kernel.org/project/mptcp/patch/ced184831757eaae9e690f65d799809ed22cae28.1776469069.git.tanggeliang@kylinos.cn/
---
 tools/testing/selftests/kselftest_harness.h | 1 +
 1 file changed, 1 insertion(+)