syzbot


UBSAN: shift-out-of-bounds in aio_iiro_16_attach

Status: upstream: reported on 2025/07/21 19:38
Reported-by: syzbot+93be9bb02390ec5ca613@syzkaller.appspotmail.com
First crash: 11d, last: 9d11h
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 UBSAN: shift-out-of-bounds in aio_iiro_16_attach origin:lts-only -1 C 14 4d17h 11d 0/3 upstream: reported C repro on 2025/07/21 17:32
upstream UBSAN: shift-out-of-bounds in aio_iiro_16_attach comedi -1 C 56 12d 25d 0/29 upstream: reported C repro on 2025/07/07 16:32
linux-6.6 UBSAN: shift-out-of-bounds in aio_iiro_16_attach -1 2 10d 10d 0/2 upstream: reported on 2025/07/22 11:15

Sample crash report:
UBSAN: shift-out-of-bounds in drivers/comedi/drivers/aio_iiro_16.c:180:9
shift exponent 67108868 is too large for 32-bit type 'int'
CPU: 0 PID: 4830 Comm: syz.3.121 Not tainted 6.1.146-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 ubsan_epilogue+0xa/0x30 lib/ubsan.c:151
 __ubsan_handle_shift_out_of_bounds+0x37c/0x400 lib/ubsan.c:321
 aio_iiro_16_attach+0x5dc/0x790 drivers/comedi/drivers/aio_iiro_16.c:180
 comedi_device_attach+0x515/0x650 drivers/comedi/drivers.c:995
 do_devconfig_ioctl drivers/comedi/comedi_fops.c:851 [inline]
 comedi_unlocked_ioctl+0x5ec/0xe90 drivers/comedi/comedi_fops.c:2131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbd27b8e9a9
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:00007fbd289b5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fbd27db5fa0 RCX: 00007fbd27b8e9a9
RDX: 00002000000000c0 RSI: 0000000040946400 RDI: 0000000000000003
RBP: 00007fbd27c10d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbd27db5fa0 R15: 00007ffde21808f8
 </TASK>
================================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/23 15:38 linux-6.1.y 3369c6df2fae e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: shift-out-of-bounds in aio_iiro_16_attach
2025/07/22 10:47 linux-6.1.y 3369c6df2fae 1555463b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: shift-out-of-bounds in aio_iiro_16_attach
2025/07/22 10:47 linux-6.1.y 3369c6df2fae 1555463b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: shift-out-of-bounds in aio_iiro_16_attach
2025/07/21 19:38 linux-6.1.y 3369c6df2fae 56d87229 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: shift-out-of-bounds in aio_iiro_16_attach
2025/07/21 19:38 linux-6.1.y 3369c6df2fae 56d87229 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: shift-out-of-bounds in aio_iiro_16_attach
* Struck through repros no longer work on HEAD.