ovl: add NULL check in ovl_alloc_inode

This was detected by fault injection test

Signed-off-by: Hirofumi Nakagawa <nklabs@gmail.com>
Fixes: 13cf199d0088 ("ovl: allocate an ovl_inode struct")
Cc: <stable@vger.kernel.org> # v4.13

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 092d150643c1..f5738e96a052 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -174,6 +174,9 @@ static struct inode *ovl_alloc_inode(struct super_block *sb)
 {
         struct ovl_inode *oi = kmem_cache_alloc(ovl_inode_cachep, GFP_KERNEL);
 
+        if (!oi)
+                return NULL;
+
         oi->cache = NULL;
         oi->redirect = NULL;
         oi->version = 0;