btrfs: fix memory leaks after failure to lookup checksums during inode logging

While logging an inode, at copy_items(), if we fail to lookup the checksums
for an extent we release the destination path, free the ins_data array and
then return immediately. However a previous iteration of the for loop may
have added checksums to the ordered_sums list, in which case we leak the
memory used by them.

So fix this by making sure we iterate the ordered_sums list and free all
its checksums before returning.

Fixes: 3650860b90cc2a ("Btrfs: remove almost all of the BUG()'s from tree-log.c")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index ea8136d..696dd86 100644 (file)
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4036,11 +4036,8 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
                                                fs_info->csum_root,
                                                ds + cs, ds + cs + cl - 1,
                                                &ordered_sums, 0);
-                               if (ret) {
-                                       btrfs_release_path(dst_path);
-                                       kfree(ins_data);
-                                       return ret;
-                               }
+                               if (ret)
+                                       break;
                        }
                }
        }
@@ -4053,7 +4050,6 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
         * we have to do this after the loop above to avoid changing the
         * log tree while trying to change the log tree.
         */
-       ret = 0;
        while (!list_empty(&ordered_sums)) {
                struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
                                                   struct btrfs_ordered_sum,