From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f208.google.com (mail-il1-f208.google.com [209.85.166.208]) (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 A811943AA4 for ; Tue, 10 Jun 2025 08:02:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.208 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749542558; cv=none; b=XdXXgqvhO/VxP8PWC1+mp7cn5h/ktTo1iGLOzIfIIOgw22RnLA3xywtrOZhnAMR2eR5q4V+PlFiOQuDNe5FysLPoMDtzi5uo6sU411/MV8+/LHf4AXe4vXoQiOtm7G+HUZA2XW6HdzJywOs25lER+vjjTNY156EfJzD2Oc4RImc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749542558; c=relaxed/simple; bh=LVepFmuGXDN992D6LP/vclUeGcHQTg9ntUJwv/nErzY=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=Vd7WpOefJxMyR0jix9CnR/K+PtXcqYsJ+0bnK29cw0vE/mQnZcfKo4OUrKZyLS7QuKTGHsZ1vPR8Ow7JOschEjqAsO764mCgwL7ydttJrOjQYsXxQMcH89hLCytK8WW0FQFduw0zgp8T/Ju7Y0lGsp/oTJj4IRMdkYHgIDkWCYU= 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=209.85.166.208 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-f208.google.com with SMTP id e9e14a558f8ab-3ddb4a92e80so68941625ab.3 for ; Tue, 10 Jun 2025 01:02:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1749542556; x=1750147356; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=Xj4vPv26zWkt7bkqTDYqd3v62tzLpe/KtfS3M8qESeI=; b=D5GFHleJ5qKUk8VANgY84l5dV8LjWkXr58MDfAjZVlq+MH24XGKwWkFLrE/4LG1Lnw Ug9861RdjI8WMG8VICdbnmsrDe0L7SlCATEYo0EYqDQD5/rV12wgQV5aSky2p/uP3afH mJUwIXBA1YJisCkV2GZGscqIg57XfIl8Yc2hJd/Knt49ePXk5jmVVXXTOZM941SSc7v6 stFI6k/nwwoXz1TRO3SSJA4QnjvH2xk7zr7RP1HYDKezUezDRGnAtB+NLSFwghoTSBl+ tS948blckne068kdqBmRHCEb+L1nfuNAicr1EVnnDLFy6K5IFv7q6MFaWEbwSfudYvA3 mvaA== X-Forwarded-Encrypted: i=1; AJvYcCUsX7wuUnV1KytizKTGq6+r7w38wsUfEs1EmIsqY8UzlwP6Ug9oafHYtnlKJeNDSXkyDcJ+niE=@vger.kernel.org X-Gm-Message-State: AOJu0YyIrH2EjrKP9eNksXghJRmQGVChvZzGZC8CdsHtvGXSe6aHgP0i EmUTqvsXyVK9ITJvlesCWDm5ieTenPY52g5/KUCNvYREfH6fjGFul8c6+b/hqLsLHf10ACobomS Qp509y8UXg2tGknzpTF0tDd7bHNeWKOnP5wH879O1HQuhlHz03QIbCcOZrPY= X-Google-Smtp-Source: AGHT+IFPMDQqinEcAbhz/4hz3Vv8ZYqqoKZwFKb0qmCPXZC4SCu39RyWQe81dTOL8FjFx7GvtHfHoeVqDsmS84zYwXC8uFk9RGkd Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1fc4:b0:3dd:b556:18c5 with SMTP id e9e14a558f8ab-3ddede0282dmr16105525ab.21.1749542555716; Tue, 10 Jun 2025 01:02:35 -0700 (PDT) Date: Tue, 10 Jun 2025 01:02:35 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6847e69b.a70a0220.27c366.005e.GAE@google.com> Subject: [syzbot] [netfilter?] WARNING: refcount bug in nf_nat_masq_schedule From: syzbot To: coreteam@netfilter.org, davem@davemloft.net, edumazet@google.com, horms@kernel.org, kadlec@netfilter.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pabeni@redhat.com, pablo@netfilter.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: c89756bcf406 Merge tag 'pm-6.16-rc1' of git://git.kernel.o.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13abfdf4580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d2e9181801c1d2a6 dashboard link: https://syzkaller.appspot.com/bug?extid=e178f373ec62758ea18b compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-c89756bc.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/e43d06e5b003/vmlinux-c89756bc.xz kernel image: https://storage.googleapis.com/syzbot-assets/ae5bc446518d/bzImage-c89756bc.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e178f373ec62758ea18b@syzkaller.appspotmail.com ------------[ cut here ]------------ refcount_t: saturated; leaking memory. WARNING: CPU: 0 PID: 1150 at lib/refcount.c:19 refcount_warn_saturate+0x10d/0x210 lib/refcount.c:19 Modules linked in: CPU: 0 UID: 0 PID: 1150 Comm: kworker/u32:8 Not tainted 6.15.0-syzkaller-03478-gc89756bcf406 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: netns cleanup_net RIP: 0010:refcount_warn_saturate+0x10d/0x210 lib/refcount.c:19 Code: cb 97 0b 31 ff 89 de e8 21 75 e4 fc 84 db 75 a3 e8 38 7a e4 fc c6 05 c5 cb 97 0b 01 90 48 c7 c7 e0 bc f4 8b e8 34 b3 a3 fc 90 <0f> 0b 90 90 eb 83 e8 18 7a e4 fc 0f b6 1d a2 cb 97 0b 31 ff 89 de RSP: 0018:ffffc9000667f4f8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817aa8e8 RDX: ffff888029688000 RSI: ffffffff817aa8f5 RDI: 0000000000000001 RBP: ffff888024f5016c R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff888024f5016c R13: ffff888024f50000 R14: 1ffff92000ccfea6 R15: ffffc9000667f5f0 FS: 0000000000000000(0000) GS:ffff8880d69a1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2a109a CR3: 00000000481e5000 CR4: 0000000000352ef0 DR0: 000000000000006d DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __refcount_add_not_zero include/linux/refcount.h:187 [inline] __refcount_inc_not_zero include/linux/refcount.h:317 [inline] refcount_inc_not_zero include/linux/refcount.h:335 [inline] maybe_get_net include/net/net_namespace.h:279 [inline] nf_nat_masq_schedule.part.0+0x4ef/0x5f0 net/netfilter/nf_nat_masquerade.c:111 nf_nat_masq_schedule net/netfilter/nf_nat_masquerade.c:108 [inline] masq_inet6_event+0x205/0x250 net/netfilter/nf_nat_masquerade.c:295 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85 atomic_notifier_call_chain+0x71/0x1c0 kernel/notifier.c:223 addrconf_ifdown.isra.0+0xe98/0x1a90 net/ipv6/addrconf.c:3982 addrconf_notify+0x220/0x19e0 net/ipv6/addrconf.c:3780 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 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+0x319/0x630 net/core/dev.c:1731 unregister_netdevice_many_notify+0x578/0x26f0 net/core/dev.c:11942 cleanup_net+0x596/0xb30 net/core/net_namespace.c:649 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 --- 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