syzbot


general protection fault in l2cap_chan_timeout (2)

Status: upstream: reported C repro on 2022/02/18 23:43
Reported-by: syzbot+f434eceb57e3b17b85d0@syzkaller.appspotmail.com
First crash: 857d, last: 492d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 general protection fault in l2cap_chan_timeout (2) C error 2 1005d 1097d 0/1 upstream: reported C repro on 2021/06/23 21:07
upstream general protection fault in l2cap_chan_timeout (2) bluetooth 1 1125d 1121d 0/27 auto-closed as invalid on 2021/09/23 19:42
upstream general protection fault in l2cap_chan_timeout bluetooth 1 1307d 1303d 0/27 auto-closed as invalid on 2021/03/25 23:40
upstream general protection fault in l2cap_chan_timeout (3) bluetooth C inconclusive inconclusive 5 58d 865d 0/27 upstream: reported C repro on 2022/02/10 18:27
linux-4.14 general protection fault in l2cap_chan_timeout 1 1423d 1423d 0/1 auto-closed as invalid on 2020/11/29 23:43
linux-4.19 general protection fault in l2cap_chan_timeout 1 1401d 1401d 0/1 auto-closed as invalid on 2020/12/21 18:33
Fix bisection attempts (9)
Created Duration User Patch Repo Result
2023/02/19 04:54 33m bisect fix linux-4.14.y job log (0) log
2023/01/19 22:29 29m bisect fix linux-4.14.y job log (0) log
2022/09/17 10:04 27m bisect fix linux-4.14.y job log (0) log
2022/08/18 09:37 27m bisect fix linux-4.14.y job log (0) log
2022/07/19 07:16 29m bisect fix linux-4.14.y job log (0) log
2022/06/19 06:43 20m bisect fix linux-4.14.y job log (0) log
2022/05/20 06:19 20m bisect fix linux-4.14.y job log (0) log
2022/04/20 05:51 20m bisect fix linux-4.14.y job log (0) log
2022/03/20 23:42 23m bisect fix linux-4.14.y job log (0) log

Sample crash report:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 12086 Comm: kworker/0:1 Not tainted 4.14.267-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events l2cap_chan_timeout
task: ffff888096cdc580 task.stack: ffff88809b2e0000
RIP: 0010:__lock_acquire+0x1cc/0x3f20 kernel/locking/lockdep.c:3369
RSP: 0018:ffff88809b2e79b0 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000054 RSI: 0000000000000000 RDI: 00000000000002a0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff888096cdc580 R12: 00000000000002a0
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8beced40
FS:  0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000140 CR3: 00000000a1efa000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 __mutex_lock_common kernel/locking/mutex.c:756 [inline]
 __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893
 l2cap_chan_timeout+0x60/0x2a0 net/bluetooth/l2cap_core.c:416
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 18 00 00 00 00 48 81 c4 80 01 00 00 44 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 67 2a 00 00 49 81 3c 24 a0 a7 2f 8b 0f 84 5f 
RIP: __lock_acquire+0x1cc/0x3f20 kernel/locking/lockdep.c:3369 RSP: ffff88809b2e79b0
---[ end trace fdc2701fdf82f6a8 ]---
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	00 00                	add    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	48 81 c4 80 01 00 00 	add    $0x180,%rsp
   b:	44 89 e8             	mov    %r13d,%eax
   e:	5b                   	pop    %rbx
   f:	5d                   	pop    %rbp
  10:	41 5c                	pop    %r12
  12:	41 5d                	pop    %r13
  14:	41 5e                	pop    %r14
  16:	41 5f                	pop    %r15
  18:	c3                   	retq
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	4c 89 e2             	mov    %r12,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 67 2a 00 00    	jne    0x2a9b
  34:	49 81 3c 24 a0 a7 2f 	cmpq   $0xffffffff8b2fa7a0,(%r12)
  3b:	8b
  3c:	0f                   	.byte 0xf
  3d:	84                   	.byte 0x84
  3e:	5f                   	pop    %rdi

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/18 23:42 linux-4.14.y a35d65bedfbc 3cd800e4 .config console log report syz C ci2-linux-4-14 general protection fault in l2cap_chan_timeout
2022/10/26 20:31 linux-4.14.y 41f36d7859a7 86777b7f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 general protection fault in l2cap_chan_timeout
2022/10/08 07:32 linux-4.14.y 9d5c0b3a8e1a aea5da89 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 general protection fault in l2cap_chan_timeout
* Struck through repros no longer work on HEAD.