Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 13783 Comm: syz.4.2058 Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:comedi_buf_munge drivers/comedi/comedi_buf.c:347 [inline]
RIP: 0010:comedi_buf_write_free+0x3c8/0x7e0 drivers/comedi/comedi_buf.c:391
Code: 41 03 45 00 48 8b 4c 24 78 42 0f b6 0c 21 84 c9 4c 8b bc 24 90 00 00 00 44 8b 74 24 54 0f 85 02 01 00 00 31 d2 48 8b 4c 24 30 <f7> 31 41 89 55 00 48 8b 44 24 70 42 0f b6 04 20 84 c0 0f 85 09 01
RSP: 0018:ffffc90000007bd8 EFLAGS: 00010046
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffff888033e48480
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88802f560000
RBP: 0000000000000002 R08: 0000000000000000 R09: 00000000000000ff
R10: dffffc0000000000 R11: ffffffff88d8dbe0 R12: dffffc0000000000
R13: ffff888033e48438 R14: 0000000000000000 R15: ffff888033e48400
FS: 00007fcf2a53b6c0(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3e76a5 CR3: 000000004dc80000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000000000aa
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
comedi_buf_write_samples+0x369/0x5a0 drivers/comedi/comedi_buf.c:602
das16m1_handler+0x213/0x4b0 drivers/comedi/drivers/das16m1.c:413
das16m1_interrupt+0xaf/0x180 drivers/comedi/drivers/das16m1.c:470
__handle_irq_event_percpu+0x289/0x980 kernel/irq/handle.c:158
handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210
handle_edge_irq+0x267/0x9c0 kernel/irq/chip.c:797
generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
handle_irq arch/x86/kernel/irq.c:254 [inline]
call_irq_handler arch/x86/kernel/irq.c:266 [inline]
__common_interrupt+0x140/0x250 arch/x86/kernel/irq.c:292
common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:285
</IRQ>
<TASK>
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
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 eb ab 5e 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> 53 dc 27 f6 65 8b 05 1c 8a 33 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc9001c5a7c00 EFLAGS: 00000206
RAX: c720afdda37b4f00 RBX: 0000000000000a02 RCX: c720afdda37b4f00
RDX: 0000000000000006 RSI: ffffffff8d982a96 RDI: 0000000000000001
RBP: ffffc9001c5a7c90 R08: ffffffff8fa0b2f7 R09: 1ffffffff1f4165e
R10: dffffc0000000000 R11: fffffbfff1f4165f R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff99dc2bc0 R15: 1ffff920038b4f80
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
uart_port_unlock_deref+0x111/0x2f0 drivers/tty/serial/serial_core.c:91
uart_write+0xe8/0x130 drivers/tty/serial/serial_core.c:637
tnc_init drivers/net/hamradio/6pack.c:525 [inline]
sixpack_open+0x6ce/0x9c0 drivers/net/hamradio/6pack.c:617
tty_ldisc_open+0x9e/0x100 drivers/tty/tty_ldisc.c:432
tty_set_ldisc+0x373/0x560 drivers/tty/tty_ldisc.c:563
tty_ioctl+0xc38/0xde0 drivers/tty/tty_io.c:2728
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcf2978e9a9
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:00007fcf2a53b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcf299b6080 RCX: 00007fcf2978e9a9
RDX: 00002000000000c0 RSI: 0000000000005423 RDI: 0000000000000007
RBP: 00007fcf29810d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcf299b6080 R15: 00007ffd04e8bf08
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:comedi_buf_munge drivers/comedi/comedi_buf.c:347 [inline]
RIP: 0010:comedi_buf_write_free+0x3c8/0x7e0 drivers/comedi/comedi_buf.c:391
Code: 41 03 45 00 48 8b 4c 24 78 42 0f b6 0c 21 84 c9 4c 8b bc 24 90 00 00 00 44 8b 74 24 54 0f 85 02 01 00 00 31 d2 48 8b 4c 24 30 <f7> 31 41 89 55 00 48 8b 44 24 70 42 0f b6 04 20 84 c0 0f 85 09 01
RSP: 0018:ffffc90000007bd8 EFLAGS: 00010046
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffff888033e48480
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88802f560000
RBP: 0000000000000002 R08: 0000000000000000 R09: 00000000000000ff
R10: dffffc0000000000 R11: ffffffff88d8dbe0 R12: dffffc0000000000
R13: ffff888033e48438 R14: 0000000000000000 R15: ffff888033e48400
FS: 00007fcf2a53b6c0(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3e76a5 CR3: 000000004dc80000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000000000aa
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 41 03 45 00 add 0x0(%r13),%eax
4: 48 8b 4c 24 78 mov 0x78(%rsp),%rcx
9: 42 0f b6 0c 21 movzbl (%rcx,%r12,1),%ecx
e: 84 c9 test %cl,%cl
10: 4c 8b bc 24 90 00 00 mov 0x90(%rsp),%r15
17: 00
18: 44 8b 74 24 54 mov 0x54(%rsp),%r14d
1d: 0f 85 02 01 00 00 jne 0x125
23: 31 d2 xor %edx,%edx
25: 48 8b 4c 24 30 mov 0x30(%rsp),%rcx
* 2a: f7 31 divl (%rcx) <-- trapping instruction
2c: 41 89 55 00 mov %edx,0x0(%r13)
30: 48 8b 44 24 70 mov 0x70(%rsp),%rax
35: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax
3a: 84 c0 test %al,%al
3c: 0f .byte 0xf
3d: 85 09 test %ecx,(%rcx)
3f: 01 .byte 0x1