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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_NEOMUTT 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 96AA8C04AB6 for ; Mon, 3 Jun 2019 09:07:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7405225DF1 for ; Mon, 3 Jun 2019 09:07:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727888AbfFCJHd (ORCPT ); Mon, 3 Jun 2019 05:07:33 -0400 Received: from mail.us.es ([193.147.175.20]:38876 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727209AbfFCJHc (ORCPT ); Mon, 3 Jun 2019 05:07:32 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 98D52EDB0B for ; Mon, 3 Jun 2019 11:07:30 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 8CB1EDA718 for ; Mon, 3 Jun 2019 11:07:30 +0200 (CEST) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 825A2DA712; Mon, 3 Jun 2019 11:07:30 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 5B6ECDA70E; Mon, 3 Jun 2019 11:07:28 +0200 (CEST) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Mon, 03 Jun 2019 11:07:28 +0200 (CEST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from us.es (129.166.216.87.static.jazztel.es [87.216.166.129]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: 1984lsi) by entrada.int (Postfix) with ESMTPSA id 22D1F40705C3; Mon, 3 Jun 2019 11:07:28 +0200 (CEST) Date: Mon, 3 Jun 2019 11:07:27 +0200 X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: Eric Dumazet Cc: "David S . Miller" , netdev , Eric Dumazet Subject: Re: [PATCH net-next] net: fix use-after-free in kfree_skb_list Message-ID: <20190603090727.g2cxedtuwe2hhvjl@salvia> References: <20190602182418.117629-1-edumazet@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190602182418.117629-1-edumazet@google.com> User-Agent: NeoMutt/20170113 (1.7.2) X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Jun 02, 2019 at 11:24:18AM -0700, Eric Dumazet wrote: > syzbot reported nasty use-after-free [1] > > Lets remove frag_list field from structs ip_fraglist_iter > and ip6_fraglist_iter. This seens not needed anyway. > > [1] : > BUG: KASAN: use-after-free in kfree_skb_list+0x5d/0x60 net/core/skbuff.c:706 > Read of size 8 at addr ffff888085a3cbc0 by task syz-executor303/8947 [...] > > Memory state around the buggy address: > ffff888085a3ca80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffff888085a3cb00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc > >ffff888085a3cb80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb > ^ > ffff888085a3cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888085a3cc80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc > > Fixes: 0feca6190f88 ("net: ipv6: add skbuff fraglist splitter") > Fixes: c8b17be0b7a4 ("net: ipv4: add skbuff fraglist splitter") > Signed-off-by: Eric Dumazet > Cc: Pablo Neira Ayuso Acked-by: Pablo Neira Ayuso Thanks!