In the Linux kernel, the following vulnerability has been resolved: btrfs: fix the possible bioc_list memory leak during error There are t

In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix the possible bioc_list memory leak during error

There are two possible ways to leak bioc memory on
btrfs_ordered_extent::bioc_list:

• An error occurred for btrfs_insert_one_raid_extent()
  Then the function btrfs_insert_raid_extent() immediately return
  without freeing any bioc in the bioc_list.

• An ordered extent hit an IO error
  In that case the ordered extent will have BTRFS_ORDERED_IOERR set, and
  skip the call on btrfs_insert_raid_extent() completely.

Fix the problem by:

• Introduce a new helper, btrfs_cleanup_ordered_bioc_list()
  Which will remove all bioc from the bioc_list, and release the bioc.

• Call the above helper for btrfs_insert_raid_extent()
  So that the cleanup helper is always called no matter what.

• Call the above helper for btrfs_finish_one_ordered()
  This is called just before the final release on the ordered extent.

This was reported by Sashiko when reviewing another patch.