[PATCH 5.7 033/204] btrfs: fix memory leaks after failure to lookup checksums during inode logging

Greg Kroah-Hartman
2020-08-20T13:10:41Z

From: Filipe Manana <fdmanana@suse.com>

commit 4f26433e9b3eb7a55ed70d8f882ae9cd48ba448b upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/btrfs/tree-log.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4040,11 +4040,8 @@ static noinline int copy_items(struct bt
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;
}
}
}
@@ -4057,7 +4054,6 @@ static noinline int copy_items(struct bt
* 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,