Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D802C433F5 for ; Fri, 10 Dec 2021 14:38:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242296AbhLJOli (ORCPT ); Fri, 10 Dec 2021 09:41:38 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:31297 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242268AbhLJOlg (ORCPT ); Fri, 10 Dec 2021 09:41:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1639147080; 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=7XKxiU3MgedSihivIPXfbGZmn05XT0xvG+ufQk1N+WQ=; b=O2v3khXqlqGhprArHCm+j3cE7iMVHDmEY6q8e601cym6gAbQKZDz7LQLmQ5298kCXSTw2i dAxA2xCiwtZizXNbbLJ/zjGAIVLm8/Zv8aoHI96uZvISMZL4k4HR7+tl+ZfBWGeze4n7EU p1DJ4rH0LwkcGByCCryOKcKmnYLQ0zI= Received: from mail-qk1-f200.google.com (mail-qk1-f200.google.com [209.85.222.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-28-CfIpzXDQMPWnJFqH8jz-YQ-1; Fri, 10 Dec 2021 09:37:59 -0500 X-MC-Unique: CfIpzXDQMPWnJFqH8jz-YQ-1 Received: by mail-qk1-f200.google.com with SMTP id bj32-20020a05620a192000b0046dcca212b6so10436250qkb.6 for ; Fri, 10 Dec 2021 06:37:59 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:user-agent:mime-version:content-transfer-encoding; bh=7XKxiU3MgedSihivIPXfbGZmn05XT0xvG+ufQk1N+WQ=; b=oo395zfrzilijeiUG2iAeBSvzUBFOW4orQ7A555evvbX/DMmIgbcQ5+SJ2BKAofyTf MrAQa13LPLccr9aguKPgKuoUOBvPj5rmZYw6Z3hRe5UQNtLhq19pOkD2Giz0DcFX4Qnr Azc66pnMeWglduSnsOYRW7y+MyyOjP8kacv0TACaGrp5DVZBoCE+tYogOhNUaSaV0ebp 4vwUh1TcFqrsWpg5Dx1s3hDBjWNCrLmmXG054WX24gnKTVp83cQOsW2VsPgQCMf3E7sh 8CYRokUWyadn9poqUuRgrSyFPrJjd67KV6GTc4aosiIzAKMbaMmgilVeBonFWYfF4z6R us8A== X-Gm-Message-State: AOAM531Grz+qy1LVK3G+9jNdsQWwtej60D1zDImP3xkhZ3MokT50R7Gk b0WHXgG4jmr06wuXp1tjsLDVKImCMSnhZ1f2TRc0FmIcE8NmD7XIrkWtxtsARBQN/pxEb8huV5Z N57htq2wgKamC341ozshXFxWs X-Received: by 2002:a05:622a:48e:: with SMTP id p14mr26872971qtx.553.1639147078956; Fri, 10 Dec 2021 06:37:58 -0800 (PST) X-Google-Smtp-Source: ABdhPJzmHHLdtzJvWqOcnVU8AcC3NlrCPmChU0xnKTY5iq+BqjhLk/HYFTvIUg/aaHe9l0TjIZv9Bg== X-Received: by 2002:a05:622a:48e:: with SMTP id p14mr26872944qtx.553.1639147078722; Fri, 10 Dec 2021 06:37:58 -0800 (PST) Received: from gerbillo.redhat.com (146-241-237-50.dyn.eolo.it. [146.241.237.50]) by smtp.gmail.com with ESMTPSA id l17sm1224892qkj.85.2021.12.10.06.37.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Dec 2021 06:37:58 -0800 (PST) Message-ID: Subject: Re: [syzbot] general protection fault in inet_csk_accept From: Paolo Abeni To: Eric Dumazet , syzbot , Florian Westphal Cc: davem@davemloft.net, dsahern@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, yoshfuji@linux-ipv6.org Date: Fri, 10 Dec 2021 15:37:54 +0100 In-Reply-To: References: <0000000000004c679505d2c8c1d4@google.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.1 (3.42.1-1.fc35) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2021-12-10 at 03:13 -0800, Eric Dumazet wrote: > On Fri, Dec 10, 2021 at 3:09 AM syzbot > wrote: > > > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: 2a987e65025e Merge tag 'perf-tools-fixes-for-v5.16-2021-12.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=166f73adb00000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=221ffc09e39ebbd1 > > dashboard link: https://syzkaller.appspot.com/bug?extid=e4d843bb96a9431e6331 > > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16280ae5b00000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1000fdc5b00000 > > > > The issue was bisected to: > > > > Note to MPTCP maintainers, I think this issue is MPTCP one,  Indeed it is, thanks for the head-up! > and the bisection result shown here seems not relevant. yep. > The C repro is however correct, I trigger an immediate crash. The repro is not triggering here - but I'm using a different kconfig. Still the repro itself gives a good hint on the root cause. I'm testing a patch with syzbot. Thanks! Paolo