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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 D71E4C433ED for ; Tue, 6 Apr 2021 17:58:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B73CD6124C for ; Tue, 6 Apr 2021 17:58:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235698AbhDFR6o (ORCPT ); Tue, 6 Apr 2021 13:58:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234333AbhDFR6m (ORCPT ); Tue, 6 Apr 2021 13:58:42 -0400 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C78CFC06174A; Tue, 6 Apr 2021 10:58:34 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id ay2so7944299plb.3; Tue, 06 Apr 2021 10:58:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=/0Ezdo6TTMIV4q/ibcjxA5ib8Vts+E2/aSfa4Pm8Xlw=; b=O2M4esYxVNDD2b0CmxjVzfdmbRa5/2CdJ1KDx7k8gjjImYg1rGy9mtdBS9COtByQP2 3mSNJxLlvkVS8nWDv5Dom6fskBqP+6FeqAfFnWOrtq7XTzasxJ2gPQSI/S3e3/kQ+QuC kUQg/iObwnXMthh5NRinOWCwarrIxVBLh4GslT1WjLcbnwYb7Hk4V9mlCOfoIob/GhnM Ydk+iNK/LOedtw2ka9BBGiAS6z73oh6UV5Ua+1ZQZkmbbUzOJsoXm9mfd3lcSvDlL9BS 5OF2+r57j7YGE0t7atWGAs4VzECMnYK7Lngj91YlG9rCWWyrTKnaSet/7jkRlJLvXIer qsFA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=/0Ezdo6TTMIV4q/ibcjxA5ib8Vts+E2/aSfa4Pm8Xlw=; b=A8EKwyahpTYLzS/3dmVkiATXWCI8yLDQeUL413JDmtEoI50j8QexcFNnPEc5gQ0RjS v1iZrBjzoeJnMVZuWzFBl9KI5LhxVZpoblBUU51h8iSCoMzn7Yr5Ta00UM0oBUfe67cR OrfaE6IOwLLhR64UbMMIxByeZk5E/dr91px8KNcud57gcqTHFs2f7Rq+crEJRZWoUwj2 NiKmDKBSiwPlOS34KENWE4z+s87Eh3tLyKa2bnm1ogNVK4wsQnV1ZzNBUuQX7NnHsudB mimuWWPFQCT1gXY81kRwFS7I+BxrViIi2cNDO48sg1H9NyAU9F2k1Tbm05MfwlFLe2Xo GzQA== X-Gm-Message-State: AOAM533XgNtLV+FL7niWozs/ok24w9Nakg895OpTLYJI3zVQFt25r5Aa 5v2NfnZt5iPFo6R1tjeftyDdGDeNJcxez+VDchc= X-Google-Smtp-Source: ABdhPJzMKWH4LeMxZBkUQvZXRLpiJ+fJNytEmS2UWHGUQ7xi7GEyQxv2bnGTvcVHT0yX8JODLz4UgamvJPVNzYH7KQw= X-Received: by 2002:a17:902:8347:b029:e7:4a2d:6589 with SMTP id z7-20020a1709028347b02900e74a2d6589mr30609818pln.64.1617731914383; Tue, 06 Apr 2021 10:58:34 -0700 (PDT) MIME-Version: 1.0 References: <0000000000008872ff05bf40e4db@google.com> In-Reply-To: <0000000000008872ff05bf40e4db@google.com> From: Cong Wang Date: Tue, 6 Apr 2021 10:58:23 -0700 Message-ID: Subject: Re: [syzbot] WARNING: suspicious RCU usage in tcp_bpf_update_proto To: syzbot Cc: Andrew Morton , Andrii Nakryiko , anton@tuxera.com, Alexei Starovoitov , Borislav Petkov , bpf , Daniel Borkmann , David Miller , "H. Peter Anvin" , Jakub Sitnicki , jmattson@google.com, John Fastabend , Joerg Roedel , Martin KaFai Lau , kpsingh@kernel.org, Jakub Kicinski , "kvm@vger.kernel.org list" , LKML , Lorenz Bauer , Ingo Molnar , Linux Kernel Network Developers , pbonzini@redhat.com, rkovhaev@gmail.com, seanjc@google.com, Song Liu , syzkaller-bugs , Thomas Gleixner , Linus Torvalds , vkuznets@redhat.com, wanpengli@tencent.com, x86 , Yonghong Song Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 6, 2021 at 2:44 AM syzbot wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 514e1150 net: x25: Queue received packets in the drivers i.. > git tree: net-next > console output: https://syzkaller.appspot.com/x/log.txt?x=112a8831d00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=7eff0f22b8563a5f > dashboard link: https://syzkaller.appspot.com/bug?extid=320a3bc8d80f478c37e4 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1532d711d00000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15f44c5ed00000 > > The issue was bisected to: > > commit 4dfe6bd94959222e18d512bdf15f6bf9edb9c27c > Author: Rustam Kovhaev > Date: Wed Feb 24 20:00:30 2021 +0000 > > ntfs: check for valid standard information attribute This is caused by one of my sockmap patches. > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=16207a81d00000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=15207a81d00000 > console output: https://syzkaller.appspot.com/x/log.txt?x=11207a81d00000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+320a3bc8d80f478c37e4@syzkaller.appspotmail.com > Fixes: 4dfe6bd94959 ("ntfs: check for valid standard information attribute") > > ============================= > WARNING: suspicious RCU usage > 5.12.0-rc4-syzkaller #0 Not tainted > ----------------------------- > include/linux/skmsg.h:286 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > rcu_scheduler_active = 2, debug_locks = 1 > 1 lock held by syz-executor383/8454: > #0: ffff888013a99b48 (clock-AF_INET){++..}-{2:2}, at: sk_psock_drop+0x2c/0x460 net/core/skmsg.c:788 > > stack backtrace: > CPU: 1 PID: 8454 Comm: syz-executor383 Not tainted 5.12.0-rc4-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:79 [inline] > dump_stack+0x141/0x1d7 lib/dump_stack.c:120 > sk_psock include/linux/skmsg.h:286 [inline] > tcp_bpf_update_proto+0x530/0x5f0 net/ipv4/tcp_bpf.c:504 > sk_psock_restore_proto include/linux/skmsg.h:408 [inline] > sk_psock_drop+0xdf/0x460 net/core/skmsg.c:789 > sk_psock_put include/linux/skmsg.h:446 [inline] > tcp_bpf_recvmsg+0x42d/0x480 net/ipv4/tcp_bpf.c:208 > inet_recvmsg+0x11b/0x5d0 net/ipv4/af_inet.c:852 Oddly, I have all relevant Kconfig enabled but never see this warning when running selftests for hours.... Anyway, let me see how this should be fixed. Thanks!