[PATCH] fs: btrfs: Prevent error pointer dereference in list_subvolums()

[Dan Carpenter]

If btrfs_read_fs_root() fails with -ENOENT, then we go to the next
entry.  Fine.  But if it fails for a different reason then we need
to clean up and return an error code.  In the current code it
doesn't clean up but instead dereferences "root" and crashes.

Signed-off-by: Dan Carpenter <dan.carpenter at linaro.org>
---
I didn't CC the btrfs mailing list.  Perhaps, I should have?

 fs/btrfs/subvolume.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/btrfs/subvolume.c b/fs/btrfs/subvolume.c
index d446e7a2c418..68ca7e48e48e 100644
--- a/fs/btrfs/subvolume.c
+++ b/fs/btrfs/subvolume.c
@@ -199,6 +199,7 @@ static int list_subvolums(struct btrfs_fs_info *fs_info)
 			ret = PTR_ERR(root);
 			if (ret == -ENOENT)
 				goto next;
+			goto out;
 		}
 		ret = list_one_subvol(root, result);
 		if (ret < 0)
-- 
2.39.2