syzbot


divide error in comedi_inc_scan_progress

Status: upstream: reported on 2025/07/08 17:52
Subsystems: comedi
[Documentation on labels]
Reported-by: syzbot+af53dea94b16396bc646@syzkaller.appspotmail.com
First crash: 109d, last: 2d00h
Discussions (3)
Title Replies (including bot) Last reply
[syzbot] [kernel?] divide error in comedi_inc_scan_progress 4 (5) 2025/10/20 17:29
[syzbot] Monthly comedi report (Sep 2025) 0 (1) 2025/09/24 12:39
[syzbot] Monthly comedi report (Jul 2025) 0 (1) 2025/07/24 09:32
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 divide error in comedi_inc_scan_progress 2 2 92d 94d 0/2 upstream: reported on 2025/07/22 05:26

Sample crash report:
Oops: divide error: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 31233 Comm: syz.0.6011 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:comedi_inc_scan_progress+0x1cc/0x340 drivers/comedi/drivers.c:563
Code: 00 00 00 03 43 2c 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 14 11 84 d2 74 09 80 fa 03 0f 8e 53 01 00 00 31 d2 <f7> b3 80 00 00 00 89 53 2c e8 16 74 fc f8 48 8d 7b 34 48 b8 00 00
RSP: 0018:ffffc90000007d90 EFLAGS: 00010046
RAX: 0000000000000001 RBX: ffff888076704c00 RCX: 1ffff1100ece0990
RDX: 0000000000000000 RSI: ffffffff88c08578 RDI: ffff888076704c80
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f566a5716c0(0000) GS:ffff888124a0c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4cf8bb3ad8 CR3: 000000005c989000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 comedi_buf_write_samples+0x406/0x640 drivers/comedi/comedi_buf.c:603
 parport_interrupt+0xec/0x150 drivers/comedi/drivers/comedi_parport.c:218
 __handle_irq_event_percpu+0x236/0x920 kernel/irq/handle.c:203
 handle_irq_event_percpu kernel/irq/handle.c:240 [inline]
 handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:257
 handle_edge_irq+0x3ca/0x9e0 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:310 [inline]
 __common_interrupt+0xd0/0x2f0 arch/x86/kernel/irq.c:325
 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:318
 </IRQ>
 <TASK>
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
RIP: 0010:__unix_dgram_recvmsg+0x37d/0xc30 net/unix/af_unix.c:2638
Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 24 08 00 00 49 8b 77 18 48 8b 7c 24 20 e8 7c 97 fe ff e8 47 07 bd f7 49 8d 47 70 <48> 89 c2 48 89 44 24 10 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03
RSP: 0018:ffffc900036d7860 EFLAGS: 00000246
RAX: ffff8880490f97f0 RBX: ffff888067a39980 RCX: ffffc90018637000
RDX: 0000000000080000 RSI: ffffffff89fff2b9 RDI: ffff888067a3a770
RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000001 R12: ffff888067a39f08
R13: ffff888067a3a0c0 R14: ffff888067a39a68 R15: ffff8880490f9780
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2700
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 ____sys_recvmsg+0x5f9/0x6b0 net/socket.c:2848
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2892
 do_recvmmsg+0x2fe/0x750 net/socket.c:2987
 __sys_recvmmsg net/socket.c:3061 [inline]
 __do_sys_recvmmsg net/socket.c:3084 [inline]
 __se_sys_recvmmsg net/socket.c:3077 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3077
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f566978efc9
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:00007f566a571038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f56699e6090 RCX: 00007f566978efc9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004
RBP: 00007f5669811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56699e6128 R14: 00007f56699e6090 R15: 00007fffa7154b68
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:comedi_inc_scan_progress+0x1cc/0x340 drivers/comedi/drivers.c:563
Code: 00 00 00 03 43 2c 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 14 11 84 d2 74 09 80 fa 03 0f 8e 53 01 00 00 31 d2 <f7> b3 80 00 00 00 89 53 2c e8 16 74 fc f8 48 8d 7b 34 48 b8 00 00
RSP: 0018:ffffc90000007d90 EFLAGS: 00010046
RAX: 0000000000000001 RBX: ffff888076704c00 RCX: 1ffff1100ece0990
RDX: 0000000000000000 RSI: ffffffff88c08578 RDI: ffff888076704c80
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f566a5716c0(0000) GS:ffff888124a0c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4cf8bb3ad8 CR3: 000000005c989000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	00 00                	add    %al,(%rax)
   2:	03 43 2c             	add    0x2c(%rbx),%eax
   5:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
   c:	fc ff df
   f:	48 89 f9             	mov    %rdi,%rcx
  12:	48 c1 e9 03          	shr    $0x3,%rcx
  16:	0f b6 14 11          	movzbl (%rcx,%rdx,1),%edx
  1a:	84 d2                	test   %dl,%dl
  1c:	74 09                	je     0x27
  1e:	80 fa 03             	cmp    $0x3,%dl
  21:	0f 8e 53 01 00 00    	jle    0x17a
  27:	31 d2                	xor    %edx,%edx
* 29:	f7 b3 80 00 00 00    	divl   0x80(%rbx) <-- trapping instruction
  2f:	89 53 2c             	mov    %edx,0x2c(%rbx)
  32:	e8 16 74 fc f8       	call   0xf8fc744d
  37:	48 8d 7b 34          	lea    0x34(%rbx),%rdi
  3b:	48                   	rex.W
  3c:	b8                   	.byte 0xb8

Crashes (38):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/23 01:11 upstream dd72c8fcf6d3 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root divide error in comedi_inc_scan_progress
2025/10/22 00:40 upstream 6548d364a3e8 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root divide error in comedi_inc_scan_progress
2025/10/21 09:10 upstream 211ddde0823f 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root divide error in comedi_inc_scan_progress
2025/10/21 09:10 upstream 211ddde0823f 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root divide error in comedi_inc_scan_progress
2025/10/20 18:46 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/10/20 18:45 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/10/20 18:43 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/10/20 18:43 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/10/20 18:13 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/10/20 17:36 upstream 211ddde0823f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/09/23 20:36 upstream cec1e6e5d1ab 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root divide error in comedi_inc_scan_progress
2025/07/30 14:59 upstream 4b290aae788e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root divide error in comedi_inc_scan_progress
2025/07/30 06:21 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root divide error in comedi_inc_scan_progress
2025/07/30 06:21 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root divide error in comedi_inc_scan_progress
2025/07/24 07:08 upstream 01a412d06bc5 0c1d6ded .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/07/23 16:03 upstream 89be9a83ccf1 e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/07/23 13:01 upstream 89be9a83ccf1 e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/07/22 16:47 upstream 89be9a83ccf1 85deaf45 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/07/22 06:39 upstream 89be9a83ccf1 1555463b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root divide error in comedi_inc_scan_progress
2025/07/21 15:39 upstream 89be9a83ccf1 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/07/21 12:58 upstream 89be9a83ccf1 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root divide error in comedi_inc_scan_progress
2025/07/09 03:38 upstream d006330be3f7 abade794 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/07/08 03:22 upstream d7b8f8e20813 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/07/08 00:11 upstream d7b8f8e20813 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root divide error in comedi_inc_scan_progress
2025/08/05 02:45 linux-next 5c5a10f0be96 abdcb213 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/08/04 15:46 linux-next 5c5a10f0be96 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/31 01:56 linux-next d086c886ceb9 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/30 07:57 linux-next d086c886ceb9 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/29 04:41 linux-next d086c886ceb9 c4a95487 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/27 00:47 linux-next d086c886ceb9 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/24 15:51 linux-next d086c886ceb9 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/24 15:50 linux-next d086c886ceb9 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/24 11:15 linux-next d086c886ceb9 0c1d6ded .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/24 06:12 linux-next d086c886ceb9 0c1d6ded .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/22 09:29 linux-next d086c886ceb9 1555463b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/22 06:07 linux-next d086c886ceb9 1555463b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce divide error in comedi_inc_scan_progress
2025/07/22 03:45 linux-next d086c886ceb9 0b3788a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root divide error in comedi_inc_scan_progress
2025/07/20 09:40 linux-next d086c886ceb9 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root divide error in comedi_inc_scan_progress
* Struck through repros no longer work on HEAD.