Hello, syzbot found the following issue on: HEAD commit: a1d21081 Merge git://git.kernel.org/pub/scm/linux/kernel/g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11c77891900000 kernel config: https://syzkaller.appspot.com/x/.config?x=9c89856ae5fc8b6 dashboard link: https://syzkaller.appspot.com/bug?extid=7f4d3ecf4d3480301722 compiler: gcc (GCC) 10.1.0-syz 20200507 userspace arch: i386 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1180847a900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7f4d3ecf4d3480301722@xxxxxxxxxxxxxxxxxxxxxxxxx list_del corruption. prev->next should be ffff8880913ab4b8, but was ffff8880890c54b8 ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:51! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout RIP: 0010:__list_del_entry_valid.cold+0xf/0x55 lib/list_debug.c:51 Code: e8 5a ab bf fd 0f 0b 48 89 f1 48 c7 c7 40 ff 93 88 4c 89 e6 e8 46 ab bf fd 0f 0b 48 89 ee 48 c7 c7 e0 00 94 88 e8 35 ab bf fd <0f> 0b 4c 89 ea 48 89 ee 48 c7 c7 20 00 94 88 e8 21 ab bf fd 0f 0b RSP: 0018:ffffc90000d8fb18 EFLAGS: 00010282 RAX: 0000000000000054 RBX: ffff8880913ab4b8 RCX: 0000000000000000 RDX: ffff8880a968a480 RSI: ffffffff815dbc57 RDI: fffff520001b1f55 RBP: ffff8880913ab4b8 R08: 0000000000000054 R09: ffff8880ae7318e7 R10: 0000000000000000 R11: 00000000000c3a18 R12: ffff8880890c54b8 R13: ffff88809914f4b8 R14: ffff88809914f000 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000081570f0 CR3: 00000000a6dc2000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry include/linux/list.h:132 [inline] list_del_init include/linux/list.h:204 [inline] bt_accept_unlink+0x26/0x280 net/bluetooth/af_bluetooth.c:187 l2cap_sock_teardown_cb+0x197/0x400 net/bluetooth/l2cap_sock.c:1544 l2cap_chan_del+0xad/0x1300 net/bluetooth/l2cap_core.c:618 l2cap_chan_close+0x118/0xb10 net/bluetooth/l2cap_core.c:823 l2cap_chan_timeout+0x173/0x450 net/bluetooth/l2cap_core.c:436 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Modules linked in: ---[ end trace ea2f8b77c156d63d ]--- RIP: 0010:__list_del_entry_valid.cold+0xf/0x55 lib/list_debug.c:51 Code: e8 5a ab bf fd 0f 0b 48 89 f1 48 c7 c7 40 ff 93 88 4c 89 e6 e8 46 ab bf fd 0f 0b 48 89 ee 48 c7 c7 e0 00 94 88 e8 35 ab bf fd <0f> 0b 4c 89 ea 48 89 ee 48 c7 c7 20 00 94 88 e8 21 ab bf fd 0f 0b RSP: 0018:ffffc90000d8fb18 EFLAGS: 00010282 RAX: 0000000000000054 RBX: ffff8880913ab4b8 RCX: 0000000000000000 RDX: ffff8880a968a480 RSI: ffffffff815dbc57 RDI: fffff520001b1f55 RBP: ffff8880913ab4b8 R08: 0000000000000054 R09: ffff8880ae7318e7 R10: 0000000000000000 R11: 00000000000c3a18 R12: ffff8880890c54b8 R13: ffff88809914f4b8 R14: ffff88809914f000 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000080f0b38 CR3: 0000000009a8d000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- 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@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
