From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3EE9C43387 for ; Mon, 7 Jan 2019 13:00:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1FD4206BB for ; Mon, 7 Jan 2019 13:00:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546866025; bh=0e2IVA6aBRnOrzUZwNqWhCkwW54tu34JaU/qXezzldI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jR8mCh+BiVYmpLen6t1b2yEZmFXTn6f03AeT4oZKZhzgskkXyT/fy5CANAz0K6Obi VfvkMg3J1NUUN7u3wJQT0z94uAYqDNBoa0GJI7HmoEN1F5oNNfufgWTDLsjrAdIy4e rWKWhu+Va4wJdiYiiTymbgpD46PzXbrV2VG+1vpY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729969AbfAGNAY (ORCPT ); Mon, 7 Jan 2019 08:00:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:47844 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730435AbfAGNAT (ORCPT ); Mon, 7 Jan 2019 08:00:19 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8145E206BB; Mon, 7 Jan 2019 13:00:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546866019; bh=0e2IVA6aBRnOrzUZwNqWhCkwW54tu34JaU/qXezzldI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QPqUFzYUQtvgxZFULetwrJZZX+i7PoESQ6clUfSxEqbPaNCo8bqOEQe+77hEZL6Bi O/am3X8Z/rnSx0NjIT/biNfntfqxrQDa3TMGrHfx5uY9ku8bEcUu2AsOc1+C+D7wdf K/CmUIkteYAddGEojgpPHnOVdmsayB/DmmzY8yy4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+8993c0fa96d57c399735@syzkaller.appspotmail.com, "Michael S. Tsirkin" , John Fastabend , Jason Wang , Cong Wang , "David S. Miller" Subject: [PATCH 4.14 019/101] ptr_ring: wrap back ->producer in __ptr_ring_swap_queue() Date: Mon, 7 Jan 2019 13:32:07 +0100 Message-Id: <20190107105334.007994537@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190107105330.372621917@linuxfoundation.org> References: <20190107105330.372621917@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cong Wang [ Upstream commit aff6db454599d62191aabc208930e891748e4322 ] __ptr_ring_swap_queue() tries to move pointers from the old ring to the new one, but it forgets to check if ->producer is beyond the new size at the end of the operation. This leads to an out-of-bound access in __ptr_ring_produce() as reported by syzbot. Reported-by: syzbot+8993c0fa96d57c399735@syzkaller.appspotmail.com Fixes: 5d49de532002 ("ptr_ring: resize support") Cc: "Michael S. Tsirkin" Cc: John Fastabend Cc: Jason Wang Signed-off-by: Cong Wang Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/linux/ptr_ring.h | 2 ++ 1 file changed, 2 insertions(+) --- a/include/linux/ptr_ring.h +++ b/include/linux/ptr_ring.h @@ -551,6 +551,8 @@ static inline void **__ptr_ring_swap_que else if (destroy) destroy(ptr); + if (producer >= size) + producer = 0; __ptr_ring_set_size(r, size); r->producer = producer; r->consumer_head = 0;