From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3EBF21170E for ; Mon, 11 Sep 2023 14:22:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 97ECBC433C8; Mon, 11 Sep 2023 14:22:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1694442136; bh=uK6B+E+MEo2nobXMhOl0ICGnD4aF0mNB5RLoXeypuu4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B7YtKr1WTF09XhM/ct3Ej6YOfuehtr77p5UZVsDGbWZ/cvcC9UIKGDU/6XkarbJt7 yZ7EoHuKn8loGd6/lpixX/4DFXd05ZIF9L2QMVjdq5k5Cc+7I0uThfldKqo5Fx7PjH WxXqsLwUJfiBKdsWDLEQgSyrNbyEiWrbaWZhra0w= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Pavel Begunkov , Jens Axboe Subject: [PATCH 6.5 658/739] io_uring: fix false positive KASAN warnings Date: Mon, 11 Sep 2023 15:47:37 +0200 Message-ID: <20230911134709.489927597@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230911134650.921299741@linuxfoundation.org> References: <20230911134650.921299741@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pavel Begunkov commit 569f5308e54352a12181cc0185f848024c5443e8 upstream. io_req_local_work_add() peeks into the work list, which can be executed in the meanwhile. It's completely fine without KASAN as we're in an RCU read section and it's SLAB_TYPESAFE_BY_RCU. With KASAN though it may trigger a false positive warning because internal io_uring caches are sanitised. Remove sanitisation from the io_uring request cache for now. Cc: stable@vger.kernel.org Fixes: 8751d15426a31 ("io_uring: reduce scheduling due to tw") Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/c6fbf7a82a341e66a0007c76eefd9d57f2d3ba51.1691541473.git.asml.silence@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- io_uring/io_uring.c | 1 - io_uring/io_uring.h | 1 - 2 files changed, 2 deletions(-) --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -229,7 +229,6 @@ static inline void req_fail_link_node(st static inline void io_req_add_to_cache(struct io_kiocb *req, struct io_ring_ctx *ctx) { wq_stack_add_head(&req->comp_list, &ctx->submit_state.free_list); - kasan_poison_object_data(req_cachep, req); } static __cold void io_ring_ctx_ref_free(struct percpu_ref *ref) --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -354,7 +354,6 @@ static inline struct io_kiocb *io_extrac struct io_kiocb *req; req = container_of(ctx->submit_state.free_list.next, struct io_kiocb, comp_list); - kasan_unpoison_object_data(req_cachep, req); wq_stack_extract(&ctx->submit_state.free_list); return req; }