From: Zhou Yuhang <zhouyuhang@kylinos.cn>

Add the missing close() in the pid_max_cb() function.

Signed-off-by: Zhou Yuhang <zhouyuhang@kylinos.cn>
---
 tools/testing/selftests/pid_namespace/pid_max.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/pid_namespace/pid_max.c b/tools/testing/selftests/pid_namespace/pid_max.c
index 96f274f0582b..41f8b943bc96 100644
--- a/tools/testing/selftests/pid_namespace/pid_max.c
+++ b/tools/testing/selftests/pid_namespace/pid_max.c
@@ -61,6 +61,7 @@ static int pid_max_cb(void *data)
 	}
 
 	ret = write(fd, "500", sizeof("500") - 1);
+	close(fd);
 	if (ret < 0) {
 		fprintf(stderr, "%m - Failed to write pid_max\n");
 		return -1;
-- 
2.33.0