From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f80.google.com (mail-io1-f80.google.com [209.85.166.80]) (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 26DE5220F56 for ; Fri, 9 May 2025 19:59:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746820767; cv=none; b=XijOxFGKhjm3JACoZTRmQ3rUQy3SPaf1lU2RizQw9i7POWCLcxfk0YMEsh+4CyBcXIvrHOGsumUwnbU+VHbA/UCgt4LLqqn61Cjvr3zOtHsiaXrPrF2UvGcavNSaUJqAGVHqIdN7h3vWaHMVkeXyIpLUPvEWVfgZefGSdVOYbT0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746820767; c=relaxed/simple; bh=WBicAQQ7I7jD+BXfAXJcmzJUHZtYsTXi4lYFgkk6PiM=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=k/tJrukUBmeLLodLx6EyBay6ItJ71A/fksMAme80txUhq4NXEsnS1D6T224esX4vry3LSDKAp0M0GLHEFvOjvlbbmAM/PJNViYK8VtTlmfAzxLU6aerH1XY0qkE2HBXXICag1b+uX/mUH8gf8lCQrxETCYNFVeoG3OlLVQ9Mbwc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.80 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-io1-f80.google.com with SMTP id ca18e2360f4ac-85c552b10b9so213426639f.1 for ; Fri, 09 May 2025 12:59:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1746820765; x=1747425565; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=5HHdjPaJZATsD4Stzjdp0FvRUeXTSmH41+zYifft2k8=; b=h0Gc9RfXh54GBNA+AkfkX294utm1Wl4DNN97C4w03qgson0Iths9xdDnnHPCTUDaom 6qx+cv1iq44/+EFl9Q3szcLINOKY9WWzZT7G8j14xFJQi7RPhqMS7exN3drLyjgqA0yH QdNLC8mAC8rtSO3Yjw7/TkQfcZjHUgLuq3DK+iAnWbI80ThDyBhtRt1nsXsbY8IemkNP 3YKCRc+v8x/5/FiXPCrLbnxBFaEPs41omhMliHE/LEjXR2zF1VoKEuPBGTEfSHbpBgnE xiSviz6yHBAbpIx/ErLyrDrZEusFdxVNwvFPy6cXSzfQf6uPhcA5yjCdQVIXMlCKXZvr DcOA== X-Forwarded-Encrypted: i=1; AJvYcCW3OR1yQlmmp7wKzAAcFiOr/uyPZKMcRLPrKdiNDo7F+gBIZWX56inZU/SDbvOgzF4RnK10gASFj/vRIdY=@vger.kernel.org X-Gm-Message-State: AOJu0YzZPjEpxMJAjN9iSqh172AolYv+CScLboSdYASYsgv8eJxZLnrj fLREbEZPJSLTBSOye6TZBykHWRLapE44nIz4QXr5/hAMqSjktOxMxsyoWZJp/FX9ZmHIsJue6xD hh77Y387mUZepVWevFF80pe0uJH9PA3JdEvPS5sc0ONnv6cfvmIAM4ZU= X-Google-Smtp-Source: AGHT+IHeboep2/ZgtFNAhDHSbks4MCSLzuCqS7IShy4118ffGTy8D7WOEd5KBH9UtQ1fVwyRzbNH/0MfHv8FulD/cQ+t4Xmd+ijv Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6602:154c:b0:864:4a9c:1bd7 with SMTP id ca18e2360f4ac-86763392674mr650551839f.0.1746820765271; Fri, 09 May 2025 12:59:25 -0700 (PDT) Date: Fri, 09 May 2025 12:59:25 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <681e5e9d.050a0220.a19a9.013c.GAE@google.com> Subject: [syzbot] [net?] KMSAN: uninit-value in __ipv6_dev_mc_dec (2) From: syzbot To: davem@davemloft.net, dsahern@kernel.org, edumazet@google.com, horms@kernel.org, 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: 02ddfb981de8 Merge tag 'scsi-fixes' of git://git.kernel.or.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13a14670580000 kernel config: https://syzkaller.appspot.com/x/.config?x=9dc42c34a3f5c357 dashboard link: https://syzkaller.appspot.com/bug?extid=4472ecce287501aa597a compiler: Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/7dc8afe7520f/disk-02ddfb98.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/3194559250c2/vmlinux-02ddfb98.xz kernel image: https://storage.googleapis.com/syzbot-assets/86c7c494f08f/bzImage-02ddfb98.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+4472ecce287501aa597a@syzkaller.appspotmail.com ===================================================== BUG: KMSAN: uninit-value in __ipv6_dev_mc_dec+0x68a/0xd30 net/ipv6/mcast.c:1014 __ipv6_dev_mc_dec+0x68a/0xd30 net/ipv6/mcast.c:1014 addrconf_leave_solict net/ipv6/addrconf.c:2254 [inline] __ipv6_ifa_notify+0xf97/0x1990 net/ipv6/addrconf.c:6299 addrconf_ifdown+0x1c61/0x32e0 net/ipv6/addrconf.c:3978 addrconf_notify+0x183/0x1d10 net/ipv6/addrconf.c:3777 notifier_call_chain kernel/notifier.c:85 [inline] raw_notifier_call_chain+0xdd/0x410 kernel/notifier.c:453 call_netdevice_notifiers_info+0x1ac/0x2b0 net/core/dev.c:2176 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline] call_netdevice_notifiers net/core/dev.c:2228 [inline] dev_close_many+0x52a/0x8f0 net/core/dev.c:1731 unregister_netdevice_many_notify+0x1106/0x4970 net/core/dev.c:11952 unregister_netdevice_many net/core/dev.c:12046 [inline] unregister_netdevice_queue+0x3b1/0x600 net/core/dev.c:11889 unregister_netdevice include/linux/netdevice.h:3374 [inline] __tun_detach+0x16c8/0x20c0 drivers/net/tun.c:620 tun_detach drivers/net/tun.c:636 [inline] tun_chr_close+0xb7/0x290 drivers/net/tun.c:3390 __fput+0x608/0x1040 fs/file_table.c:465 ____fput+0x25/0x30 fs/file_table.c:493 task_work_run+0x206/0x2b0 kernel/task_work.c:227 resume_user_mode_work+0x105/0x160 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x7b/0xb0 kernel/entry/common.c:218 __do_fast_syscall_32+0xbd/0x110 arch/x86/entry/syscall_32.c:309 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Local variable maddr.i created at: addrconf_leave_solict net/ipv6/addrconf.c:2248 [inline] __ipv6_ifa_notify+0xe6f/0x1990 net/ipv6/addrconf.c:6299 addrconf_ifdown+0x1c61/0x32e0 net/ipv6/addrconf.c:3978 CPU: 1 UID: 0 PID: 10959 Comm: syz.4.717 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 ===================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup