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=-3.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=no 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 ED7F5C433E0 for ; Sun, 5 Jul 2020 19:08:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C41F920739 for ; Sun, 5 Jul 2020 19:08:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=c0d3.blue header.i=@c0d3.blue header.b="ScLBZ4iE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727892AbgGETI4 (ORCPT ); Sun, 5 Jul 2020 15:08:56 -0400 Received: from mail.aperture-lab.de ([138.201.29.205]:44978 "EHLO mail.aperture-lab.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727823AbgGETI4 (ORCPT ); Sun, 5 Jul 2020 15:08:56 -0400 X-Greylist: delayed 2771 seconds by postgrey-1.27 at vger.kernel.org; Sun, 05 Jul 2020 15:08:55 EDT Date: Sun, 5 Jul 2020 21:08:51 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c0d3.blue; s=2018; t=1593976134; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8dlf83gnJimOcGLge0RE4YQ95UNZUa/xyinaF6hcyXc=; b=ScLBZ4iErn0Ka4U7KqaaDg1VueVrFtp84H2/aG3f0uGS28X0BYcFs15LJj7RPuLZaanzu0 NdXnXkh+VwdYK3b8AMcCnswepuR+sCmZnuQ8F4RMio3BBUsaBTYDqmxzqSu9lqry/rohjL 08AOQ10u1m45BPMcYdksNeTDAsBoEJjaY1czMLt+ybLjZp69Ux11tlhrJqsFvvlC3eqSiK WXed3+Xo69XCNYJrlZNFWc+1ciwJJUmLRmcm/dfW+UgLdo0T/Js1ByFx/irHtd9h31Oy+E Gt3ncm95HdhnC6w6HF5Up+nQANTiVneEN5G5FX+wVE/advm6FZqpJaNv4knCfw== From: Linus =?utf-8?Q?L=C3=BCssing?= To: Nikolay Aleksandrov Cc: netdev@vger.kernel.org, Roopa Prabhu , Martin Weinelt , "David S . Miller" , bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net] bridge: mcast: Fix MLD2 Report IPv6 payload length check Message-ID: <20200705190851.GC2648@otheros> References: <20200705182234.10257-1-linus.luessing@c0d3.blue> <093beb97-87e8-e112-78ad-b3e4fe230cdb@cumulusnetworks.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <093beb97-87e8-e112-78ad-b3e4fe230cdb@cumulusnetworks.com> Authentication-Results: ORIGINATING; auth=pass smtp.auth=linus.luessing@c0d3.blue smtp.mailfrom=linus.luessing@c0d3.blue Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Jul 05, 2020 at 09:33:13PM +0300, Nikolay Aleksandrov wrote: > On 05/07/2020 21:22, Linus Lüssing wrote: > > Commit e57f61858b7c ("net: bridge: mcast: fix stale nsrcs pointer in > > igmp3/mld2 report handling") introduced a small bug which would potentially > > lead to accepting an MLD2 Report with a broken IPv6 header payload length > > field. > > > > The check needs to take into account the 2 bytes for the "Number of > > Sources" field in the "Multicast Address Record" before reading it. > > And not the size of a pointer to this field. > > > > Fixes: e57f61858b7c ("net: bridge: mcast: fix stale nsrcs pointer in igmp3/mld2 report handling") > > Signed-off-by: Linus Lüssing > > --- > > net/bridge/br_multicast.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > I'd rather be more concerned with it rejecting a valid report due to wrong size. The ptr > size would always be bigger. :) > > Thanks! > Acked-by: Nikolay Aleksandrov Aiy, you're right, it's the other way round. I'll update the commit message and send a v2 in a minute, with your Acked-by included.