diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 62f5195d0076..f75de9f6c0ad 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -1986,7 +1986,6 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans, int err) */ BUG_ON(list_empty(&cur_trans->list)); - list_del_init(&cur_trans->list); if (cur_trans == fs_info->running_transaction) { cur_trans->state = TRANS_STATE_COMMIT_DOING; spin_unlock(&fs_info->trans_lock); @@ -1995,6 +1994,17 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans, int err) spin_lock(&fs_info->trans_lock); } + + /* + * Now that we know no one else is still using the transaction we can + * remove the transaction from the list of transactions. This avoids + * the transaction kthread from cleaning up the transaction while some + * other task is still using it, which could result in a use-after-free + * on things like log trees, as it forces the transaction kthread to + * wait for this transaction to be cleaned up by us. + */ + list_del_init(&cur_trans->list); + spin_unlock(&fs_info->trans_lock); btrfs_cleanup_one_transaction(trans->transaction, fs_info);