Commit 770594e7 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring/zcrx: warn on freelist violations 



The freelist is appropriately sized to always be able to take a free
niov, but let's be more defensive and check the invariant with a
warning. That should help to catch any double-free issues.

Suggested-by: default avatarKai Aizen <kai@snailsploit.com>
Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://patch.msgid.link/2f3cea363b04649755e3b6bb9ab66485a95936d5.1776760901.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 4f02cc40

io_uring/zcrx.c

+2 −0
Original line number Diff line number Diff line
@@ -602,6 +602,8 @@ static void io_zcrx_return_niov_freelist(struct net_iov *niov) 
	struct io_zcrx_area *area = io_zcrx_iov_to_area(niov);



	guard(spinlock_bh)(&area->freelist_lock);

	if (WARN_ON_ONCE(area->free_count >= area->nia.num_niovs))

		return;

	area->freelist[area->free_count++] = net_iov_idx(niov);

}