From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo2-f7.google.com (mail-oo2-f7.google.com [74.125.231.135]) (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 A63F94A0157 for ; Fri, 18 Sep 2026 21:24:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.135 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789766678; cv=none; b=UFTsdG4CA8db/NevvyFNl7YVJSERmLeQYfjnIbF4YeFrt0pGOADQGGysSsz/qMMHsSUkWDoI+DvBshUrkIVcJbCIBTLmKoCOHLM4UsEVKOKjXqxzS/fnwJMm91ILSHL5p/VSrtj0qHcdj/t8QfBYdY5bnbe6bfHf3LPihpml0Mk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789766678; c=relaxed/simple; bh=vysW34Y5MuVI7mh8rvcO+tz1BNsiP2Tm2MaYv/6cUS0=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=O2/CE4uUYlt9tW4YrkLfnThuicGKklvDhFwfxt6j5cPJJFBeXCj4GaXp7C8T9Et1adTHGSZVdzDhrzaBcVaOWN4RUP+yLBSRMdlLz5kpyGNabPtaLdbxMKhDDcnxj9H2Uyi5XdJ3e5XV61ABKwLnJrATXC8Ur6xxaYSCJhw9RsA= 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=74.125.231.135 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-oo2-f7.google.com with SMTP id 006d021491bc7-6b1bebb3ae8so497390eaf.1 for ; Fri, 18 Sep 2026 14:24:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1789766675; x=1790371475; h=content-type:to:from:subject:message-id:in-reply-to:date :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=u1u3CHkcCfNdtkHpr2f6Q8I6xzAzYCLm9kLKPD5T5jo=; b=nXHn9tQA8ETX14LDGqdHj+XRNZ+q9dLLZ67qfdkxrukZEDaJplAnKKY4LASZt49AM6 yGGPhSimFZDGSsFYddWBiv7oUrB33QS2xwRW8JT+QDSbKFmENwgJlKF7lA+//BlIoMvB I14aYj6MuNi/kz6G5m+pml6pXlwMJMIGzBOpP7AFzmuJ6EwGlqvFgH1lU7pbktfmhZLv 6OUvFCtVVqyhkPnHRBfMwDxfg2lNt8XZgzab5OhX3aoMnZTuXmq0qMP+jejRBwDwncjK QLJHe9NtSn5l/heWI6XZ8qz58M3JtC7E1zfOqH0zeDqzWzV5OqKgOpJhNUYB47Kg8AVL l5IA== X-Forwarded-Encrypted: i=1; AKwUvBzXfR5OjhgWYezroeXolNN9O57iFpBXQYREH6S+9d+n1NmDpWeB47UcTt5w825CgoLcXUum6BSl6F4Yfp4=@vger.kernel.org X-Gm-Message-State: AFuF++kxndBZThXHCuCzvWwbJD0V0VTKc0aiT3OvBMJ1osZEIyRLUqsu BuoTLvrx7DGWMF1+71t1BWrInAfX4z/6kiz0Ab0okGZGxHUqDKs7yHbp8nnlSpo/9HrLCjUJITv e8GMn1caqE4UuO4wZPSRjC789zMaVYyfvFnNE/MagN2u0z6gdYnNDwexwbNs= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:a284:20b0:6cd:3fdb:fa6a with SMTP id 006d021491bc7-6cd3fdbfe8dmr588537eaf.85.1789766675670; Fri, 18 Sep 2026 14:24:35 -0700 (PDT) Date: Fri, 18 Sep 2026 14:24:35 -0700 In-Reply-To: <6aa3307a.6e6c5f9e.28f11f.003a.GAE@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6aadac13.b398a7c9.1f86be.003c.GAE@google.com> Subject: Re: [syzbot] [net?] WARNING: locking bug in finish_task_switch (3) From: syzbot To: davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, kuniyu@google.com, linux-kernel@vger.kernel.org, luto@kernel.org, ncardwell@google.com, netdev@vger.kernel.org, pabeni@redhat.com, peterz@infradead.org, syzkaller-bugs@googlegroups.com, tglx@kernel.org Content-Type: text/plain; charset="UTF-8" syzbot has found a reproducer for the following issue on: HEAD commit: 50d05c7c76c9 Merge tag 'landlock-7.3-rc3' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15b5f8c9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=5e4e3a0e188a497e dashboard link: https://syzkaller.appspot.com/bug?extid=b5ddc2aecb8d1b29c871 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 userspace arch: i386 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12ab4525580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14d4e915580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/daf497619736/disk-50d05c7c.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/748fbd82f647/vmlinux-50d05c7c.xz kernel image: https://storage.googleapis.com/syzbot-assets/e61c59099d07/bzImage-50d05c7c.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+b5ddc2aecb8d1b29c871@syzkaller.appspotmail.com ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(1) WARNING: kernel/locking/lockdep.c:238 at hlock_class kernel/locking/lockdep.c:238 [inline], CPU#0: syz.1.28/6067 WARNING: kernel/locking/lockdep.c:238 at check_wait_context kernel/locking/lockdep.c:4923 [inline], CPU#0: syz.1.28/6067 WARNING: kernel/locking/lockdep.c:238 at __lock_acquire+0x5f0/0x2de0 kernel/locking/lockdep.c:5238, CPU#0: syz.1.28/6067 Modules linked in: CPU: 0 UID: 0 PID: 6067 Comm: syz.1.28 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:hlock_class kernel/locking/lockdep.c:238 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4923 [inline] RIP: 0010:__lock_acquire+0x5f7/0x2de0 kernel/locking/lockdep.c:5238 Code: 83 3d bc f2 fa 18 00 75 27 90 e8 94 e8 37 03 85 c0 74 1c 83 3d ed 29 d7 0e 00 75 13 48 8d 3d e0 32 da 0e 48 c7 c6 29 f3 59 8e <67> 48 0f b9 3a 90 31 c9 0f b6 81 c4 00 00 00 84 c0 0f 84 76 ff ff RSP: 0000:ffffc90003a6e538 EFLAGS: 00010046 RAX: 0000000000000001 RBX: ffff88802f13e9b8 RCX: ffff88802f13ddc0 RDX: 0000000040000000 RSI: ffffffff8e59f329 RDI: ffffffff907d6580 RBP: ffff88802f13e9c0 R08: ffffffff907a5c83 R09: 1ffffffff20f4b90 R10: dffffc0000000000 R11: fffffbfff20f4b91 R12: 0000000000000004 R13: 0000000000000000 R14: ffff88802f13ddc0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888124cd2000(0063) knlGS:00000000f67c3b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f71c8c10 CR3: 00000000711ba000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 finish_lock_switch kernel/sched/core.c:5254 [inline] finish_task_switch+0x16e/0xc60 kernel/sched/core.c:5375 context_switch kernel/sched/core.c:5529 [inline] __schedule+0x17e3/0x58f0 kernel/sched/core.c:7276 __schedule_loop kernel/sched/core.c:7353 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7368 __lock_sock+0x162/0x2c0 net/core/sock.c:3238 __lock_sock_fast+0x94/0xe0 net/core/sock.c:3900 lock_sock_fast include/net/sock.h:1746 [inline] tcp_get_info+0x26d/0x2b70 net/ipv4/tcp.c:4250 inet_sk_diag_fill+0xdb6/0x18c0 net/ipv4/inet_diag.c:330 sk_diag_fill+0x2e6/0xd50 net/ipv4/tcp_diag.c:284 tcp_diag_dump+0x1ba6/0x2020 net/ipv4/tcp_diag.c:538 __inet_diag_dump net/ipv4/inet_diag.c:823 [inline] inet_diag_dump_compat+0x274/0x490 net/ipv4/inet_diag.c:927 netlink_dump+0x711/0xee0 net/netlink/af_netlink.c:2331 __netlink_dump_start+0x589/0x7b0 net/netlink/af_netlink.c:2446 netlink_dump_start include/linux/netlink.h:341 [inline] inet_diag_rcv_msg_compat+0x214/0x420 net/ipv4/inet_diag.c:962 sock_diag_rcv_msg+0x4b0/0x5f0 net/core/sock_diag.c:-1 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/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+0x177/0x240 net/socket.c:2799 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x27a/0x6a0 arch/x86/entry/syscall_32.c:291 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:316 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf700f0ec Code: 90 85 d2 74 0a 89 ce 81 e6 ff 0f 00 00 89 32 85 c0 74 05 c1 e9 0c 89 08 31 c0 5e 5d c3 90 0f 1f 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 58 b8 RSP: 002b:00000000f67c350c EFLAGS: 00000206 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 0000000080000240 RDX: 0000000004004010 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 83 3d bc f2 fa 18 00 cmpl $0x0,0x18faf2bc(%rip) # 0x18faf2c3 7: 75 27 jne 0x30 9: 90 nop a: e8 94 e8 37 03 call 0x337e8a3 f: 85 c0 test %eax,%eax 11: 74 1c je 0x2f 13: 83 3d ed 29 d7 0e 00 cmpl $0x0,0xed729ed(%rip) # 0xed72a07 1a: 75 13 jne 0x2f 1c: 48 8d 3d e0 32 da 0e lea 0xeda32e0(%rip),%rdi # 0xeda3303 23: 48 c7 c6 29 f3 59 8e mov $0xffffffff8e59f329,%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 90 nop 30: 31 c9 xor %ecx,%ecx 32: 0f b6 81 c4 00 00 00 movzbl 0xc4(%rcx),%eax 39: 84 c0 test %al,%al 3b: 0f .byte 0xf 3c: 84 76 ff test %dh,-0x1(%rsi) 3f: ff .byte 0xff --- 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.