[PATCH] mm/shrinker_debug: Fix possible memory leak in shrinker_debugfs_rename function.

[Liu Ye]

After calling debugfs_change_name function, the return value should be
checked and the old name restored. If debugfs_change_name fails, the new
name memory should be freed.

Signed-off-by: Liu Ye <liuye@xxxxxxxxxx>
---
 mm/shrinker_debug.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c
index 794bd433cce0..20eaee3e97f7 100644
--- a/mm/shrinker_debug.c
+++ b/mm/shrinker_debug.c
@@ -214,10 +214,14 @@ int shrinker_debugfs_rename(struct shrinker *shrinker, const char *fmt, ...)
 	ret = debugfs_change_name(shrinker->debugfs_entry, "%s-%d",
 			shrinker->name, shrinker->debugfs_id);
 
+	if (ret) {
+		shrinker->name = old;
+		kfree_const(new);
+	} else {
+		kfree_const(old);
+	}
 	mutex_unlock(&shrinker_mutex);
 
-	kfree_const(old);
-
 	return ret;
 }
 EXPORT_SYMBOL(shrinker_debugfs_rename);
-- 
2.25.1