Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 5506 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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 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: ffff88807acb9a80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888075027000 RBP: 0000000000000002 R08: 0000000000000000 R09: 00000000000000ff R10: dffffc0000000000 R11: ffffffff88bb6ff0 R12: dffffc0000000000 R13: ffff88807acb9a38 R14: 0000000000000000 R15: ffff88807acb9a00 FS: 00007f09286bc740(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff5ac9f5f98 CR3: 000000001deac000 CR4: 00000000003526f0 Call Trace: 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+0x295/0xab0 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:257 handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855 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:-1 [inline] __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:325 common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:318 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688 RIP: 0010:__do_sys_ppoll fs/select.c:-1 [inline] RIP: 0010:__se_sys_ppoll+0x1ee/0x260 fs/select.c:1095 Code: 48 8b 74 24 18 e8 c2 77 4a ff 41 89 c7 31 ff 89 c6 e8 16 b0 82 ff 45 85 ff 74 0a e8 cc ab 82 ff 49 63 c7 eb 2c e8 c2 ab 82 ff <48> 8b 3c 24 48 8b 74 24 08 4c 89 f2 e8 91 16 00 00 48 8d 7c 24 60 RSP: 0018:ffffc90003017e00 EFLAGS: 00000293 RAX: ffffffff823d37ee RBX: 0000000000000000 RCX: ffff88802e8f9e40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003017ed0 R08: ffffffff8f9e6677 R09: 1ffffffff1f3ccce R10: dffffc0000000000 R11: fffffbfff1f3cccf R12: dffffc0000000000 R13: 1ffff92000602fc4 R14: 0000000000000000 R15: 0000000000000000 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0928746407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffc0c0114c0 EFLAGS: 00000202 ORIG_RAX: 000000000000010f RAX: ffffffffffffffda RBX: 00007f09286bc740 RCX: 00007f0928746407 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 000055d0037a04a0 RBP: 00007ffc0c011800 R08: 0000000000000008 R09: 0000000000000000 R10: 00007ffc0c011800 R11: 0000000000000202 R12: 000055cfe84645e0 R13: 000055d00379ad40 R14: 0000000000000000 R15: 00007ffc0c0115b0 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 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: ffff88807acb9a80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888075027000 RBP: 0000000000000002 R08: 0000000000000000 R09: 00000000000000ff R10: dffffc0000000000 R11: ffffffff88bb6ff0 R12: dffffc0000000000 R13: ffff88807acb9a38 R14: 0000000000000000 R15: ffff88807acb9a00 FS: 00007f09286bc740(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff5ac9f5f98 CR3: 000000001deac000 CR4: 00000000003526f0 ---------------- 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