From 483242714fcc853f3f5ef728116f5ec168468bca Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Mon, 4 Nov 2024 12:02:47 +0000 Subject: [PATCH] io_uring: prevent speculating sq_array indexing The SQ index array consists of user provided indexes, which io_uring then uses to index the SQ, and so it's susceptible to speculation. For all other queues io_uring tracks heads and tails in kernel, and they shouldn't need any special care. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/c6c7a25962924a55869e317e4fdb682dfdc6b279.1730687889.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- io_uring/io_uring.c | 1 + 1 file changed, 1 insertion(+) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 7c1ca36b117b..751b9e19da6e 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -2245,6 +2245,7 @@ static bool io_get_sqe(struct io_ring_ctx *ctx, const struct io_uring_sqe **sqe) READ_ONCE(ctx->rings->sq_dropped) + 1); return false; } + head = array_index_nospec(head, ctx->sq_entries); } /*