Btrfs: fix subvol_name leak on error in btrfs_mount()

btrfs_parse_early_options() can fail due to error while scanning devices
(-o device= option), but still strdup() subvol_name string:

mount -o subvol=SUBV,device=BAD_DEVICE <dev> <mnt>

So free subvol_name string on error.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 6befcaf253bd..58e9492230ce 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -905,8 +905,10 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags,
         error = btrfs_parse_early_options(data, mode, fs_type,
                                           &subvol_name, &subvol_objectid,
                                           &subvol_rootid, &fs_devices);
-        if (error)
+        if (error) {
+                kfree(subvol_name);
                 return ERR_PTR(error);
+        }
 
         if (subvol_name) {
                 root = mount_subvol(subvol_name, flags, device_name, data);