From: Pavel Begunkov Date: Wed, 29 Mar 2023 14:03:43 +0000 (+0100) Subject: io_uring/rsrc: fix rogue rsrc node grabbing X-Git-Tag: v6.6.7~3123^2~4 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4ff0b50de8cabba055efe50bbcb7506c41a69835;p=platform%2Fkernel%2Flinux-starfive.git io_uring/rsrc: fix rogue rsrc node grabbing We should not be looking at ctx->rsrc_node and anyhow modifying the node without holding uring_lock, grabbing references in such a way is not safe either. Cc: stable@vger.kernel.org Fixes: 5106dd6e74ab6 ("io_uring: propagate issue_flags state down to file assignment") Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/1202ede2d7bb90136e3482b2b84aad9ed483e5d6.1680098433.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h index 2b87436..f27f497 100644 --- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -144,15 +144,13 @@ static inline void io_req_set_rsrc_node(struct io_kiocb *req, unsigned int issue_flags) { if (!req->rsrc_node) { - req->rsrc_node = ctx->rsrc_node; + io_ring_submit_lock(ctx, issue_flags); - if (!(issue_flags & IO_URING_F_UNLOCKED)) { - lockdep_assert_held(&ctx->uring_lock); + lockdep_assert_held(&ctx->uring_lock); - io_charge_rsrc_node(ctx); - } else { - percpu_ref_get(&req->rsrc_node->refs); - } + req->rsrc_node = ctx->rsrc_node; + io_charge_rsrc_node(ctx); + io_ring_submit_unlock(ctx, issue_flags); } }