From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f207.google.com (mail-il1-f207.google.com [209.85.166.207]) (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 D7052AD24 for ; Tue, 21 Oct 2025 00:02:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761004978; cv=none; b=Ig1W2DDs8jv2ORsIabqTMARg/FMSpQuOBL03z+n4NohSADdG8CE5rmcvKgPLpKO977HPAff9EoCDEM1dk2FmuOa24umkSoGZJw8rJvUcK5opXNLI84G0LDjbUBXEqOIkkzEBzKgYHDsnAK/g4goLcpf+XxC7nbjNyusgvP5YJPg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761004978; c=relaxed/simple; bh=4jlamZdGevMQhmRlakFM+RZJoM+8Sn+L8wwQZntPgbE=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=ck84yizdN+ZP9J+R3zLtYMq5PA9uO4AJQoCM8v+p5aoHOW5FTTd1gRdegP48o+WUBfJQ2zV9PP71gAEIU5n/CLqHmDgYt/Edf+q0G1tnKU5GVURnKKYbd7JaNtdhbuH7P+E6f5F51d4JOzeMRBkaZjDCX1swuBjlvBVTM3W86gk= 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=209.85.166.207 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-f207.google.com with SMTP id e9e14a558f8ab-430c316fcb3so157962955ab.2 for ; Mon, 20 Oct 2025 17:02:56 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761004976; x=1761609776; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=SGtGnSMcxz8uRlspj8XhrY0JQrEt5g0a6j8yhS08xiY=; b=ktPpdi3S7Hdui1NTWh9nmaxE9zFmZD4T+OMK1CSolttkbNhy7i5mqhPXWjA5oPXvOf n8X4qZSMA5pQ7vhw15q6eTI5Fq3YQGIm52VNyHA0Na2Rr9PBPS+Pg2sT51IjkYq3rOn+ jBE5QZvQoBANtMiGTKzQJSpOE1a8D6z7oJLmmxMjWsUYl+9DXyLB9d9Twg4nUothU03r whUnPA/HWLtgB7T//KXoxqYvyQD2foR0Tf9eOOuhSSPV9LICpBT8gyoEMV0dA9upPX86 13YvpuxI5kI4M9ke33ru4cnxKV9043rn1tMnM0RqqBH9EY9nsTLFtigkhMr7Ipy8Ueso +cRA== X-Forwarded-Encrypted: i=1; AJvYcCVDTnAZMM+6zuq8XeO9yM7dLTJdPVqy4JJ1VxpnYWt9+JfSM2AWzYUUJ2eqwz3FCD1Vw195oUctWPoMqZA=@vger.kernel.org X-Gm-Message-State: AOJu0YzJI79WDGtqEtwFePV0hi5oIxBmOEV3J5KB8eEIh2ksTJy75NJT EYYJjthzuT6rlJT11/KcqeFoYR8NFbt4eZM1WtD+UUPA3z8w0TEdfffJtJ22KsfhoDPuaCJguVC 5U9+vrUtIggtiK3txc2xfoK+yDfQsw72ojK3tshLrSLxIwI0RuF22L0nfi3U= X-Google-Smtp-Source: AGHT+IEmG+qDHLq+vF+wGve5vCFuV2izBRmasF6GBoQY1Gaf6l+lphX6gWoaecZ2wp1icepziYRG3QQDdn/btL3OCMLOtLGh7NLA Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:4415:20b0:430:c536:cfad with SMTP id e9e14a558f8ab-430c536d097mr177309805ab.16.1761004976084; Mon, 20 Oct 2025 17:02:56 -0700 (PDT) Date: Mon, 20 Oct 2025 17:02:56 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <68f6cdb0.a70a0220.205af.0039.GAE@google.com> Subject: [syzbot] [virt?] [net?] possible deadlock in vsock_linger From: syzbot To: davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, sgarzare@redhat.com, syzkaller-bugs@googlegroups.com, virtualization@lists.linux.dev Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: d9043c79ba68 Merge tag 'sched_urgent_for_v6.18_rc2' of git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=130983cd980000 kernel config: https://syzkaller.appspot.com/x/.config?x=f3e7b5a3627a90dd dashboard link: https://syzkaller.appspot.com/bug?extid=10e35716f8e4929681fa compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17f0f52f980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11ea9734580000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-d9043c79.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0546b6eaf1aa/vmlinux-d9043c79.xz kernel image: https://storage.googleapis.com/syzbot-assets/81285b4ada51/bzImage-d9043c79.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+10e35716f8e4929681fa@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.17/6098 is trying to acquire lock: ffff8880363b8258 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1679 [inline] ffff8880363b8258 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: vsock_linger+0x25e/0x4d0 net/vmw_vsock/af_vsock.c:1066 but task is already holding lock: ffffffff906260a8 (vsock_register_mutex){+.+.}-{4:4}, at: vsock_assign_transport+0xf2/0x900 net/vmw_vsock/af_vsock.c:469 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (vsock_register_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x193/0x1060 kernel/locking/mutex.c:760 vsock_registered_transport_cid net/vmw_vsock/af_vsock.c:560 [inline] vsock_find_cid net/vmw_vsock/af_vsock.c:570 [inline] __vsock_bind+0x1b5/0xa10 net/vmw_vsock/af_vsock.c:752 vsock_bind+0xc6/0x120 net/vmw_vsock/af_vsock.c:1002 __sys_bind_socket net/socket.c:1874 [inline] __sys_bind_socket net/socket.c:1866 [inline] __sys_bind+0x1a7/0x260 net/socket.c:1905 __do_sys_bind net/socket.c:1910 [inline] __se_sys_bind net/socket.c:1908 [inline] __x64_sys_bind+0x72/0xb0 net/socket.c:1908 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sk_lock-AF_VSOCK){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 lock_sock_nested+0x41/0xf0 net/core/sock.c:3720 lock_sock include/net/sock.h:1679 [inline] vsock_linger+0x25e/0x4d0 net/vmw_vsock/af_vsock.c:1066 virtio_transport_close net/vmw_vsock/virtio_transport_common.c:1271 [inline] virtio_transport_release+0x52a/0x640 net/vmw_vsock/virtio_transport_common.c:1291 vsock_assign_transport+0x320/0x900 net/vmw_vsock/af_vsock.c:502 vsock_connect+0x201/0xee0 net/vmw_vsock/af_vsock.c:1578 __sys_connect_file+0x141/0x1a0 net/socket.c:2102 __sys_connect+0x13b/0x160 net/socket.c:2121 __do_sys_connect net/socket.c:2127 [inline] __se_sys_connect net/socket.c:2124 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2124 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(vsock_register_mutex); lock(sk_lock-AF_VSOCK); lock(vsock_register_mutex); lock(sk_lock-AF_VSOCK); *** DEADLOCK *** 1 lock held by syz.0.17/6098: #0: ffffffff906260a8 (vsock_register_mutex){+.+.}-{4:4}, at: vsock_assign_transport+0xf2/0x900 net/vmw_vsock/af_vsock.c:469 stack backtrace: CPU: 3 UID: 0 PID: 6098 Comm: syz.0.17 Not tainted syzkaller #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 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x275/0x350 kernel/locking/lockdep.c:2043 check_noncircular+0x14c/0x170 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 lock_sock_nested+0x41/0xf0 net/core/sock.c:3720 lock_sock include/net/sock.h:1679 [inline] vsock_linger+0x25e/0x4d0 net/vmw_vsock/af_vsock.c:1066 virtio_transport_close net/vmw_vsock/virtio_transport_common.c:1271 [inline] virtio_transport_release+0x52a/0x640 net/vmw_vsock/virtio_transport_common.c:1291 vsock_assign_transport+0x320/0x900 net/vmw_vsock/af_vsock.c:502 vsock_connect+0x201/0xee0 net/vmw_vsock/af_vsock.c:1578 __sys_connect_file+0x141/0x1a0 net/socket.c:2102 __sys_connect+0x13b/0x160 net/socket.c:2121 __do_sys_connect net/socket.c:2127 [inline] __se_sys_connect net/socket.c:2124 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2124 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f767bf8efc9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff0a2857b8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f767c1e5fa0 RCX: 00007f767bf8efc9 RDX: 0000000000000010 RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007f767c011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f767c1e5fa0 R14: 00007f767c1e5fa0 R15: 0000000000000003 --- 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 syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. 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