4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro <viro@xxxxxxxxxxxxxxxxxx> commit 3df629d873f8683af6f0d34dfc743f637966d483 upstream. get in sync with mount_bdev() handling of the same Reported-by: syzbot+c54f8e94e6bba03b04e9@xxxxxxxxxxxxxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/gfs2/ops_fstype.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -1353,6 +1353,9 @@ static struct dentry *gfs2_mount_meta(st struct path path; int error; + if (!dev_name || !*dev_name) + return ERR_PTR(-EINVAL); + error = kern_path(dev_name, LOOKUP_FOLLOW, &path); if (error) { pr_warn("path_lookup on %s returned error %d\n",