3.16.60-rc1 review patch. If anyone has any objections, please let me know.
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From: Nikolay Borisov nborisov@suse.com
commit d87ff75863e92a500538ab53318c5740f196631e upstream.
As with every function which deals with modifying the btree btrfs_uuid_tree_rem can fail for any number of reasons (ie. EIO/ENOMEM). Handle return error value from this function gracefully by aborting the transaction.
Fixes: dd5f9615fc5c ("Btrfs: maintain subvolume items in the UUID tree") Signed-off-by: Nikolay Borisov nborisov@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com [bwh: Backported to 3.16: - btrfs_{abort,end}_transaction() take a pointer to btrfs_root - Adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -5051,11 +5051,17 @@ static long _btrfs_ioctl_set_received_su received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); if (received_uuid_changed && - !btrfs_is_empty_uuid(root_item->received_uuid)) - btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, - root_item->received_uuid, - BTRFS_UUID_KEY_RECEIVED_SUBVOL, - root->root_key.objectid); + !btrfs_is_empty_uuid(root_item->received_uuid)) { + ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, + root_item->received_uuid, + BTRFS_UUID_KEY_RECEIVED_SUBVOL, + root->root_key.objectid); + if (ret && ret != -ENOENT) { + btrfs_abort_transaction(trans, root, ret); + btrfs_end_transaction(trans, root); + goto out; + } + } memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); btrfs_set_root_stransid(root_item, sa->stransid); btrfs_set_root_rtransid(root_item, sa->rtransid);