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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=unavailable 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 70C11C282E1 for ; Tue, 23 Apr 2019 17:10:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46F73208E4 for ; Tue, 23 Apr 2019 17:10:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729259AbfDWRKb (ORCPT ); Tue, 23 Apr 2019 13:10:31 -0400 Received: from coyote.holtmann.net ([212.227.132.17]:56404 "EHLO mail.holtmann.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727740AbfDWRKb (ORCPT ); Tue, 23 Apr 2019 13:10:31 -0400 Received: from marcel-macpro.fritz.box (p4FF9FD9B.dip0.t-ipconnect.de [79.249.253.155]) by mail.holtmann.org (Postfix) with ESMTPSA id 682CCCF2F8; Tue, 23 Apr 2019 19:18:39 +0200 (CEST) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.8\)) Subject: Re: [PATCH net] 6lowpan: Off by one handling ->nexthdr From: Marcel Holtmann In-Reply-To: <20190403053416.GA21913@kadam> Date: Tue, 23 Apr 2019 19:10:28 +0200 Cc: Alexander Aring , Jukka Rissanen , "David S. Miller" , linux-bluetooth@vger.kernel.org, linux-wpan@vger.kernel.org, netdev@vger.kernel.org, kernel-janitors@vger.kernel.org Content-Transfer-Encoding: 7bit Message-Id: <18F5B032-F127-4EB9-8DB8-F760C6455431@holtmann.org> References: <20190403053416.GA21913@kadam> To: Dan Carpenter X-Mailer: Apple Mail (2.3445.104.8) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Dan, > NEXTHDR_MAX is 255. What happens here is that we take a u8 value > "hdr->nexthdr" from the network and then look it up in > lowpan_nexthdr_nhcs[]. The problem is that if hdr->nexthdr is 0xff then > we read one element beyond the end of the array so the array needs to > be one element larger. > > Fixes: 92aa7c65d295 ("6lowpan: add generic nhc layer interface") > Signed-off-by: Dan Carpenter > --- > This is the only place which uses the NEXTHDR_MAX define, so I considered > changing that to 256 instead. Either fix would work. > > net/6lowpan/nhc.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) patch has been applied to bluetooth-next tree. Regards Marcel