In the Linux kernel, the following vulnerability has been resolved: ext4: regenerate buddy after block freeing failed if under fc replay This mostly reverts commit 6bd97bf273bd ("ext4: remove redundant mb_regenerate_buddy()") and reintroduces mb_regenerate_buddy(). Based on code in mb_free_blocks(), fast commit replay can end up marking as free blocks that are already marked as such. This causes corruption of the buddy bitmap so we need to regenerate it in that case.
https://git.kernel.org/stable/c/ea42d6cffb0dd27a417f410b9d0011e9859328cb
https://git.kernel.org/stable/c/c9b528c35795b711331ed36dc3dbee90d5812d4e
https://git.kernel.org/stable/c/c1317822e2de80e78f137d3a2d99febab1b80326
https://git.kernel.org/stable/c/94ebf71bddbcd4ab1ce43ae32c6cb66396d2d51a
https://git.kernel.org/stable/c/78327acd4cdc4a1601af718b781eece577b6b7d4
https://git.kernel.org/stable/c/6b0d48647935e4b8c7b75d1eccb9043fcd4ee581