4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Amir Goldstein <amir73il@xxxxxxxxx> commit 8fc646b44385ff0a9853f6590497e43049eeb311 upstream. On failure to prepare_creds(), mount fails with a random return value, as err was last set to an integer cast of a valid lower mnt pointer or set to 0 if inodes index feature is enabled. Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Fixes: 3fe6e52f0626 ("ovl: override creds with the ones from ...") Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/overlayfs/super.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -946,6 +946,7 @@ static int ovl_fill_super(struct super_b else sb->s_d_op = &ovl_dentry_operations; + err = -ENOMEM; ufs->creator_cred = cred = prepare_creds(); if (!cred) goto out_put_lower_mnt;