md/raid5-ppl: fix use-after-free in ppl_do_flush()

The loop in ppl_do_flush() continues iterating after calling
ppl_io_unit_finished(), touching io->pending_flushes and leading to a
use-after-free.

Add a break statement to stop the loop once io is freed.

Fixes: 1532d9e87e ("raid5-ppl: PPL support for disks with write-back cache enabled")
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/all/ajJF2wKYWRk4GGCK@stanley.mountain/
Signed-off-by: Sajal Gupta <sajal2005gupta@gmail.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260622142146.56637-1-sajal2005gupta@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
This commit is contained in:
Sajal Gupta
2026-06-22 19:36:03 +05:30
committed by Yu Kuai
parent f565925810
commit 371f7a1b39

View File

@@ -643,8 +643,10 @@ static void ppl_do_flush(struct ppl_io_unit *io)
log->disk_flush_bitmap = 0;
for (i = flushed_disks ; i < raid_disks; i++) {
if (atomic_dec_and_test(&io->pending_flushes))
if (atomic_dec_and_test(&io->pending_flushes)) {
ppl_io_unit_finished(io);
break;
}
}
}