From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f198.google.com (mail-il1-f198.google.com [209.85.166.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0FD695D73A for ; Fri, 12 Jan 2024 10:10:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f198.google.com with SMTP id e9e14a558f8ab-360a0a5a87dso37664395ab.0 for ; Fri, 12 Jan 2024 02:10:28 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705054228; x=1705659028; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=wq/Neynlo7rd9EMdFfz+w2uSTNXBQrlV6BSSyVMmA8Q=; b=WP0VYggQ/IIvAf0cgIxyNcUb0hypbssNnqaGqZx5CudocyXNSsnVA3Rvs/St3EoShm nd6xG962CiniC88GCTRwFEhykWpRnd+37pp4vq6gRhxcmRtN6+un5/7Duv+nPwe6Rg6B yIueRxpCJ3GVqCFmnWUvIMR/RhWSix2f1kilfHp2kB7igTBmqMFe1uUwMY9+oUPXpMoM +UtxBE3DX9WL9nBvBO3FjfY8JK2ZXHQ76Vvc3cWhEOyThXw1NXLN2U6/ZDGY45v4mcwI gmq4Zdr2QVP1FD3zkqdP7FDq7I8smxmJHBP//Gx3//TJAGWIlaZ9vUTleQTpMn09osQ2 U0Yw== X-Gm-Message-State: AOJu0YwQsF7PFjSSRfyO4Zm7oDq4wcfHikwhttfXfesuqFshgU8xFm8g DzJ/boigEDsL8lcrpDj30H5t033vQZsjhk9MV45KwObXJTRA X-Google-Smtp-Source: AGHT+IGl20DykQgHikEGY9DrhP3cYgtQLM3BTHK1OM3/ZjSp1AaJonRlHFb8otrnOonC0bofGF4ls+S9ysIJU+N+zqF654IKs5Ax Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:16cf:b0:35f:b1e7:cac with SMTP id 15-20020a056e0216cf00b0035fb1e70cacmr38175ilx.4.1705054228268; Fri, 12 Jan 2024 02:10:28 -0800 (PST) Date: Fri, 12 Jan 2024 02:10:28 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000994e09060ebcdffb@google.com> Subject: [syzbot] [net?] KCSAN: data-race in ipv6_mc_down / mld_ifc_work (2) From: syzbot To: davem@davemloft.net, dsahern@kernel.org, edumazet@google.com, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 8735c7c84d1b Merge tag '6.7rc7-smb3-srv-fix' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17948c9ae80000 kernel config: https://syzkaller.appspot.com/x/.config?x=4da1e2da456c3a7d dashboard link: https://syzkaller.appspot.com/bug?extid=a9400cabb1d784e49abf compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f263d974af01/disk-8735c7c8.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/9faf34fc0b3e/vmlinux-8735c7c8.xz kernel image: https://storage.googleapis.com/syzbot-assets/0b52a58ecd0e/bzImage-8735c7c8.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a9400cabb1d784e49abf@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in ipv6_mc_down / mld_ifc_work write to 0xffff88813a80c832 of 1 bytes by task 3771 on cpu 0: mld_ifc_stop_work net/ipv6/mcast.c:1080 [inline] ipv6_mc_down+0x10a/0x280 net/ipv6/mcast.c:2725 addrconf_ifdown+0xe32/0xf10 net/ipv6/addrconf.c:3949 addrconf_notify+0x310/0x980 notifier_call_chain kernel/notifier.c:93 [inline] raw_notifier_call_chain+0x6b/0x1c0 kernel/notifier.c:461 __dev_notify_flags+0x205/0x3d0 dev_change_flags+0xab/0xd0 net/core/dev.c:8685 do_setlink+0x9f6/0x2430 net/core/rtnetlink.c:2916 rtnl_group_changelink net/core/rtnetlink.c:3458 [inline] __rtnl_newlink net/core/rtnetlink.c:3717 [inline] rtnl_newlink+0xbb3/0x1670 net/core/rtnetlink.c:3754 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6558 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6576 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x589/0x650 net/netlink/af_netlink.c:1368 netlink_sendmsg+0x66e/0x770 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x37c/0x4d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x1e9/0x270 net/socket.c:2667 __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b write to 0xffff88813a80c832 of 1 bytes by task 22 on cpu 1: mld_ifc_work+0x54c/0x7b0 net/ipv6/mcast.c:2653 process_one_work kernel/workqueue.c:2627 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2700 worker_thread+0x525/0x730 kernel/workqueue.c:2781 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 value changed: 0x02 -> 0x00 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 22 Comm: kworker/1:0 Not tainted 6.7.0-rc7-syzkaller-00029-g8735c7c84d1b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: mld mld_ifc_work ================================================================== --- This report is generated by a bot. 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