syzbot

Oops: divide error: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 14000 Comm: syz.3.2056 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:comedi_inc_scan_progress+0x1a4/0x430 drivers/comedi/drivers.c:563
Code: b6 0c 19 84 c9 0f 85 bd 01 00 00 03 45 2c 4c 8d a5 80 00 00 00 4c 89 e1 48 c1 e9 03 0f b6 0c 19 84 c9 0f 85 cc 01 00 00 31 d2 <41> f7 34 24 41 89 17 45 89 ec eb 0f e8 4b e3 07 f9 48 bb 00 00 00
RSP: 0018:ffffc90000007c78 EFLAGS: 00010046
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88804ad19400 R08: ffff88803160b001 R09: 1ffff110062c1600
R10: dffffc0000000000 R11: ffffed10062c1601 R12: ffff88804ad19480
R13: 0000000000000002 R14: 0000000000000000 R15: ffff88804ad1942c
FS:  00007f2a3c2466c0(0000) GS:ffff888126084000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3101aff8 CR3: 0000000027c90000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 comedi_buf_write_samples+0x373/0x5a0 drivers/comedi/comedi_buf.c:603
 das16m1_handler+0x213/0x4b0 drivers/comedi/drivers/das16m1.c:413
 das16m1_interrupt+0xaf/0x180 drivers/comedi/drivers/das16m1.c:470
 __handle_irq_event_percpu+0x285/0xa60 kernel/irq/handle.c:211
 handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
 handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:265
 handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855
 generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
 handle_irq arch/x86/kernel/irq.c:255 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:326
 common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:319
 </IRQ>
 <TASK>
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 8b c7 77 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> c3 5c 3f f6 65 8b 05 5c 52 28 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90017f2f980 EFLAGS: 00000206
RAX: c4f540387e1e9c00 RBX: 0000000000000216 RCX: c4f540387e1e9c00
RDX: 0000000000000006 RSI: ffffffff8d7831da RDI: 0000000000000001
RBP: ffffc90017f2fa10 R08: ffffffff8f815077 R09: 1ffffffff1f02a0e
R10: dffffc0000000000 R11: fffffbfff1f02a0f R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff99ba5b80 R15: 1ffff92002fe5f30
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
 autoconfig drivers/tty/serial/8250/8250_port.c:1199 [inline]
 serial8250_config_port+0x144e/0x5370 drivers/tty/serial/8250/8250_port.c:3083
 univ8250_config_port+0x3b9/0x980 drivers/tty/serial/8250/8250_rsa.c:72
 uart_do_autoconfig drivers/tty/serial/serial_core.c:1174 [inline]
 uart_ioctl+0x13cb/0x1a70 drivers/tty/serial/serial_core.c:1570
 tty_ioctl+0x929/0xde0 drivers/tty/tty_io.c:2792
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2a3b38f749
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:00007f2a3c246038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2a3b5e6090 RCX: 00007f2a3b38f749
RDX: 0000000000000000 RSI: 0000000000005453 RDI: 0000000000000005
RBP: 00007f2a3b413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2a3b5e6128 R14: 00007f2a3b5e6090 R15: 00007fffe9b7b8f8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:comedi_inc_scan_progress+0x1a4/0x430 drivers/comedi/drivers.c:563
Code: b6 0c 19 84 c9 0f 85 bd 01 00 00 03 45 2c 4c 8d a5 80 00 00 00 4c 89 e1 48 c1 e9 03 0f b6 0c 19 84 c9 0f 85 cc 01 00 00 31 d2 <41> f7 34 24 41 89 17 45 89 ec eb 0f e8 4b e3 07 f9 48 bb 00 00 00
RSP: 0018:ffffc90000007c78 EFLAGS: 00010046
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88804ad19400 R08: ffff88803160b001 R09: 1ffff110062c1600
R10: dffffc0000000000 R11: ffffed10062c1601 R12: ffff88804ad19480
R13: 0000000000000002 R14: 0000000000000000 R15: ffff88804ad1942c
FS:  00007f2a3c2466c0(0000) GS:ffff888126084000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3101aff8 CR3: 0000000027c90000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	b6 0c                	mov    $0xc,%dh
   2:	19 84 c9 0f 85 bd 01 	sbb    %eax,0x1bd850f(%rcx,%rcx,8)
   9:	00 00                	add    %al,(%rax)
   b:	03 45 2c             	add    0x2c(%rbp),%eax
   e:	4c 8d a5 80 00 00 00 	lea    0x80(%rbp),%r12
  15:	4c 89 e1             	mov    %r12,%rcx
  18:	48 c1 e9 03          	shr    $0x3,%rcx
  1c:	0f b6 0c 19          	movzbl (%rcx,%rbx,1),%ecx
  20:	84 c9                	test   %cl,%cl
  22:	0f 85 cc 01 00 00    	jne    0x1f4
  28:	31 d2                	xor    %edx,%edx
* 2a:	41 f7 34 24          	divl   (%r12) <-- trapping instruction
  2e:	41 89 17             	mov    %edx,(%r15)
  31:	45 89 ec             	mov    %r13d,%r12d
  34:	eb 0f                	jmp    0x45
  36:	e8 4b e3 07 f9       	call   0xf907e386
  3b:	48                   	rex.W
  3c:	bb                   	.byte 0xbb
  3d:	00 00                	add    %al,(%rax)