From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f199.google.com (mail-oi1-f199.google.com [209.85.167.199]) (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 206A4388396 for ; Mon, 12 Oct 2026 01:59:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791770374; cv=none; b=fpzBOkOeRPt/hEIAwsGV1wyETkVZmXn4fZ3koa/GRY9rX9v4L1wtqOb7JW9Q8bJWdgNT/td1Av7XWdvUJcKbYG5J28bWoZJ6bmbpGGmGcnBSgKuALLfR5hgc7kY7GmuBZL8XGkXJQ5xzSM6bUgJvFxk8CyZnWxlp1mqnosZLeI0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791770374; c=relaxed/simple; bh=oahBO1025qVPSPugkA64I7iVejIAS2a4Gsh5Tbhx5fk=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=ZS6bsO0sZAPmctxaz8pc0eGBjN2tyrEIikvTi33qXeT5SIZgLoBg5Zc/07XWfWQ6WVQzSPZDilrRf0lzFipulQs+WrUMk0JsEzkEIYwdZK0ZO0FZiQDqLUTs9YoS7ntxTIFOcyLBHxG5l83LXBLsQRwdj9UgoazV0G5Y8DRVdKg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.199 Received: by mail-oi1-f199.google.com with SMTP id 5614622812f47-4d2f0f77124so2107088b6e.3 for ; Sun, 11 Oct 2026 18:59:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791770372; x=1792375172; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=gKk9txmv0mZCyRJL6L+tG/6jg3Fga3i3/ojfl8+Y39s=; b=kEYrWu3mlAF578o0O6Eo4+qYSqT5gEratvdzkR6PG3wBUNs967VUg5m7WqrfrgjACB pEb3oj//MmPX5U1oocOEe5jqgSdNXJbtuKgJigZQcIz4HL3lE0oJolUvcLBcWQi9Sm30 gOTHphW8yKcpyi4zcUS1n1yTPwwIW3ps/xa2QM8ZjB526se3MSFyyEzrBfqrxcXQ7Cyk lJ0pBbZnJMhMq0ilDNlfDy/UIjH9K04Djz3fQNPn7CMrvI/F0JjYCyR3aZNdgG+FZ4yP gs+ZBzDF57yOvgDuObwLBOxLNmageTYccZjwnlgOzuQ6uYNs/ns2ZyEYlio52eJ38Kwr y4LA== X-Forwarded-Encrypted: i=1; AKwUvByupI2gf4GX3a+Xuhj9pCGg5w8q47eUlSieQP0I8jaZgwRDkfa9fZDM3qo73wiNsg3iBkySFy0=@vger.kernel.org X-Gm-Message-State: AFq9FYJ2vBplpgM/EsKfF2YJeRuS3G+L5fGc8VU6jTRQf/y5Oou8+ftu /l0VAsuAOeS7oRxybzfdp9ZFcKe7PV9L4lZK6gLPp+OywriTNOnrKMi7W+57l0ZFY2XQiXlNZq3 SQkEsC0V3JxIbE8ZQkYUxZdUrg7Wr9KBiXnfBPTzf+s2ssal/Z3aS93rm0oc= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:c3c2:b0:4ed:7045:d3bc with SMTP id 5614622812f47-50c50f29bf2mr7110424b6e.32.1791770372245; Sun, 11 Oct 2026 18:59:32 -0700 (PDT) Date: Sun, 11 Oct 2026 18:59:32 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6acc3f04.a150a118.27e199.003f.GAE@google.com> Subject: [syzbot] [mptcp?] WARNING in __mptcp_move_skbs_from_subflow (3) From: syzbot To: davem@davemloft.net, edumazet@kernel.org, geliang@kernel.org, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, martineau@kernel.org, matttbe@kernel.org, mptcp@lists.linux.dev, 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: af32da41b032 Merge tag 'net-7.3-rc7' of git://git.kernel.o.. git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=14b48c9c580000 kernel config: https://syzkaller.appspot.com/x/.config?x=4118aaa2d227be26 dashboard link: https://syzkaller.appspot.com/bug?extid=a0f240a492551e97b466 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/67d1818d6d97/disk-af32da41.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/903b9a3843fb/vmlinux-af32da41.xz kernel image: https://storage.googleapis.com/syzbot-assets/b878ac72b487/bzImage-af32da41.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a0f240a492551e97b466@syzkaller.appspotmail.com ------------[ cut here ]------------ 1 WARNING: net/mptcp/protocol.c:855 at __mptcp_move_skbs_from_subflow+0x11cf/0x19a0 net/mptcp/protocol.c:855, CPU#1: syz.4.337/7111 Modules linked in: CPU: 1 UID: 0 PID: 7111 Comm: syz.4.337 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 RIP: 0010:__mptcp_move_skbs_from_subflow+0x11cf/0x19a0 net/mptcp/protocol.c:855 Code: b6 04 26 84 c0 0f 85 57 05 00 00 41 c6 07 00 e9 e6 f5 ff ff e8 92 5d f7 f5 90 0f 0b 90 48 8b 5c 24 30 eb 0c e8 82 5d f7 f5 90 <0f> 0b 90 4d 89 ec 48 8b 7c 24 68 e8 11 13 01 00 e9 50 fd ff ff e8 RSP: 0018:ffffc90000a18120 EFLAGS: 00010246 RAX: ffffffff8bd0b1be RBX: ffff88802a7bf8e0 RCX: ffff888035d8be80 RDX: 8000000000000300 RSI: 0000000000000100 RDI: 0000000000004500 RBP: ffffc90000a18328 R08: 0000000000000100 R09: 1ffff110048f1958 R10: dffffc0000000000 R11: ffffed10048f1959 R12: 0000000000007fe4 R13: dffffc0000000000 R14: 000000002f8eae63 R15: 0000000000004500 FS: 00007f14a00f66c0(0000) GS:ffff888123bbf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000287000 CR3: 000000007ec44000 CR4: 00000000003526f0 Call Trace: move_skbs_to_msk net/mptcp/protocol.c:971 [inline] mptcp_data_ready+0x3f5/0xc20 net/mptcp/protocol.c:1028 subflow_data_ready+0x2bc/0x7f0 net/mptcp/subflow.c:1540 tcp_data_queue+0x1e94/0x5fa0 net/ipv4/tcp_input.c:5700 tcp_rcv_established+0xb05/0x2940 net/ipv4/tcp_input.c:6696 tcp_v4_do_rcv+0x727/0x13b0 net/ipv4/tcp_ipv4.c:1854 tcp_v4_rcv+0x27d4/0x3170 net/ipv4/tcp_ipv4.c:2248 ip_protocol_deliver_rcu+0x21d/0x440 net/ipv4/ip_input.c:207 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325 __netif_receive_skb_one_core net/core/dev.c:6297 [inline] __netif_receive_skb net/core/dev.c:6410 [inline] process_backlog+0xa6b/0x18b0 net/core/dev.c:6761 __napi_poll+0xaa/0x330 net/core/dev.c:7830 napi_poll net/core/dev.c:7893 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8050 handle_softirqs+0x226/0x860 kernel/softirq.c:645 do_softirq+0x77/0xd0 kernel/softirq.c:546 __local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:923 [inline] __dev_queue_xmit+0x1efb/0x3920 net/core/dev.c:4993 dev_queue_xmit include/linux/netdevice.h:3464 [inline] neigh_hh_output include/net/neighbour.h:544 [inline] neigh_output include/net/neighbour.h:558 [inline] ip_finish_output2+0xbda/0x10b0 net/ipv4/ip_output.c:236 NF_HOOK_COND include/linux/netfilter.h:314 [inline] ip_output+0x29f/0x450 net/ipv4/ip_output.c:437 __ip_queue_xmit+0x10df/0x1b10 net/ipv4/ip_output.c:533 __tcp_transmit_skb+0x2d18/0x47c0 net/ipv4/tcp_output.c:1717 tcp_transmit_skb net/ipv4/tcp_output.c:1734 [inline] tcp_write_xmit+0x1bfa/0x6400 net/ipv4/tcp_output.c:3062 __tcp_push_pending_frames+0x96/0x380 net/ipv4/tcp_output.c:3245 mptcp_push_release net/mptcp/protocol.c:1668 [inline] __mptcp_push_pending+0x60f/0x900 net/mptcp/protocol.c:1809 mptcp_sendmsg+0x11ea/0x1d10 net/mptcp/protocol.c:2110 sock_sendmsg_nosec+0x90/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] ____sys_sendmsg+0x54e/0x850 net/socket.c:2713 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767 __sys_sendmsg net/socket.c:2799 [inline] __do_sys_sendmsg net/socket.c:2804 [inline] __se_sys_sendmsg net/socket.c:2802 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2802 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f149f19e1d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f14a00f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f149f425fa0 RCX: 00007f149f19e1d9 RDX: 0000000000040010 RSI: 00002000000008c0 RDI: 0000000000000007 RBP: 00007f149f235888 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f149f426038 R14: 00007f149f425fa0 R15: 00007ffe2ec5e878 --- 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