This is a note to let you know that I've just added the patch titled btrfs: Explicitly handle btrfs_update_root failure to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: btrfs-explicitly-handle-btrfs_update_root-failure.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Mon Dec 18 13:28:59 CET 2017 From: Nikolay Borisov <nborisov@xxxxxxxx> Date: Thu, 28 Sep 2017 10:53:17 +0300 Subject: btrfs: Explicitly handle btrfs_update_root failure From: Nikolay Borisov <nborisov@xxxxxxxx> [ Upstream commit 9417ebc8a676487c6ec8825f92fb28f7dbeb5f4b ] btrfs_udpate_root can fail and it aborts the transaction, the correct way to handle an aborted transaction is to explicitly end with btrfs_end_transaction. Even now the code is correct since btrfs_commit_transaction would handle an aborted transaction but this is more of an implementation detail. So let's be explicit in handling failure in btrfs_update_root. Furthermore btrfs_commit_transaction can also fail and by ignoring it's return value we could have left the in-memory copy of the root item in an inconsistent state. So capture the error value which allows us to correctly revert the RO/RW flags in case of commit failure. Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/ioctl.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1842,8 +1842,13 @@ static noinline int btrfs_ioctl_subvol_s ret = btrfs_update_root(trans, fs_info->tree_root, &root->root_key, &root->root_item); + if (ret < 0) { + btrfs_end_transaction(trans); + goto out_reset; + } + + ret = btrfs_commit_transaction(trans); - btrfs_commit_transaction(trans); out_reset: if (ret) btrfs_set_root_flags(&root->root_item, root_flags); Patches currently in stable-queue which might be from nborisov@xxxxxxxx are queue-4.14/btrfs-explicitly-handle-btrfs_update_root-failure.patch queue-4.14/btrfs-undo-writable-superblocke-when-sprouting-fails.patch