btrfs: fix wrong length parameter for btrfs_cleanup_ordered_extents()

Inside nocow_one_range(), if the checksum cloning for data reloc inode
failed, we call btrfs_cleanup_ordered_extents() to cleanup the just
allocated ordered extents.

But unlike extent_clear_unlock_delalloc(),
btrfs_cleanup_ordered_extents() requires a length, not an inclusive end
bytenr.

This can be problematic, as the @end is normally way larger than @len.

This means btrfs_cleanup_ordered_extents() can be called on folios
out of the correct range, and if the out-of-range folio is under
writeback, we can incorrectly clear the ordered flag of the folio, and
trigger the DEBUG_WARN() inside btrfs_writepage_cow_fixup().

Fix the wrong parameter with correct length instead.

Fixes: 94f6c5c17e52 ("btrfs: move ordered extent cleanup to where they are allocated")
CC: stable@vger.kernel.org # 6.15+
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a2de289e662b2fe5711b9027bdc9a486cd642f9b..d740910e071a329a7bb010d9281332b0e643f491 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2015,7 +2015,7 @@ static int nocow_one_range(struct btrfs_inode *inode, struct folio *locked_folio
         * cleaered by the caller.
         */
        if (ret < 0)
-               btrfs_cleanup_ordered_extents(inode, file_pos, end);
+               btrfs_cleanup_ordered_extents(inode, file_pos, len);
        return ret;
 }