[v6.1] WARNING in l2cap_chan_del (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 882efbdd9d34 Linux 6.1.155
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1679fa7c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7eb38bd5021fec61
dashboard link: https://syzkaller.appspot.com/bug?extid=6d6cfb3e5f38c3462fd3
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/cc4ea5e30f96/disk-882efbdd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a8e2e97ac897/vmlinux-882efbdd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c6b39d17aa12/bzImage-882efbdd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6d6cfb...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 6616 at kernel/workqueue.c:1441 __queue_work+0xe2d/0xfb0 kernel/workqueue.c:1441
Modules linked in:
CPU: 0 PID: 6616 Comm: syz.4.590 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__queue_work+0xe2d/0xfb0 kernel/workqueue.c:1441
Code: e9 9d fc ff ff 48 8b 0c 24 80 e1 07 80 c1 03 38 c1 0f 8c c7 fc ff ff 48 8b 3c 24 e8 2d c9 7d 00 e9 b9 fc ff ff e8 13 9c 2d 00 <0f> 0b 48 83 c4 60 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 fd 9b 2d 00
RSP: 0018:ffffc9000607f5a8 EFLAGS: 00010083
RAX: ffffffff815332dd RBX: 0000000000010000 RCX: 0000000000080000
RDX: ffffc90012196000 RSI: 0000000000002dd4 RDI: 0000000000002dd5
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed100e5e6867
R10: ffffed100e5e6867 R11: 1ffff1100e5e6866 R12: ffff8880744a7800
R13: ffff8880744a79c0 R14: 0000000000000008 R15: ffff888072f34330
FS: 00007f10366666c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fd19ff8 CR3: 000000007c4b0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
queue_delayed_work_on+0x126/0x1e0 kernel/workqueue.c:1704
l2cap_chan_del+0x2d8/0x620 net/bluetooth/l2cap_core.c:696
l2cap_chan_close+0xf9/0x7f0 net/bluetooth/l2cap_core.c:884
l2cap_sock_shutdown+0x8fb/0xf50 net/bluetooth/l2cap_sock.c:1404
l2cap_sock_release+0x8a/0x1e0 net/bluetooth/l2cap_sock.c:1451
__sock_release net/socket.c:654 [inline]
sock_close+0xd5/0x240 net/socket.c:1400
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1ca/0x250 kernel/task_work.c:203
get_signal+0x11a6/0x1350 kernel/signal.c:2648
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f103578eec9
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:00007f1036666038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffffc RBX: 00007f10359e6270 RCX: 00007f103578eec9
RDX: 000000000000000e RSI: 0000200000000040 RDI: 0000000000000009
RBP: 00007f1035811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f10359e6308 R14: 00007f10359e6270 R15: 00007ffe6848ed88
</TASK>


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