On Tue, 21 Nov 2023, Wu Bo wrote:

If BIO error, it may goto verity_finish_io() before verity_fec_init_io(). Therefor, the fec_io->rs is not initialized and may crash when doing memory freeing in verity_fec_finish_io().

Crash call stack: die+0x90/0x2b8 __do_kernel_fault+0x260/0x298 do_bad_area+0x2c/0xdc do_translation_fault+0x3c/0x54 do_mem_abort+0x54/0x118 el1_abort+0x38/0x5c el1h_64_sync_handler+0x50/0x90 el1h_64_sync+0x64/0x6c free_rs+0x18/0xac fec_rs_free+0x10/0x24 mempool_free+0x58/0x148 verity_fec_finish_io+0x4c/0xb0 verity_end_io+0xb8/0x150

Cc: stable@vger.kernel.org # v6.0+ Fixes: 5721d4e5a9cd ("dm verity: Add optional "try_verify_in_tasklet" feature") Signed-off-by: Wu Bo bo.wu@vivo.com

---

drivers/md/dm-verity-target.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c index e115fcfe723c..beec14b6b044 100644 --- a/drivers/md/dm-verity-target.c +++ b/drivers/md/dm-verity-target.c @@ -642,7 +642,6 @@ static void verity_work(struct work_struct *w) io->in_tasklet = false;

• verity_fec_init_io(io); verity_finish_io(io, errno_to_blk_status(verity_verify_io(io)));

} @@ -792,6 +791,8 @@ static int verity_map(struct dm_target *ti, struct bio *bio) bio->bi_private = io; io->iter = bio->bi_iter;

• verity_fec_init_io(io);
• verity_submit_prefetch(v, io);

submit_bio_noacct(bio); -- 2.25.1

Reviewed-by: Mikulas Patocka mpatocka@redhat.com