Forwarded: Re: [syzbot] [kernel?] UBSAN: shift-out-of-bounds in aio_iiro_16_attach

[syzbot <syzbot+f1bb7e4ea47ea12b535c@syzkaller.appspotmail.com>]

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Subject: Re: [syzbot] [kernel?] UBSAN: shift-out-of-bounds in aio_iiro_16_attach
Author: xandfury@gmail.com

syzbot <syzbot+f1bb7e4ea47ea12b535c@syzkaller.appspotmail.com> writes:

> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    a79a588fc176 Merge tag ’pm-6.16-rc5’ of git://git.kernel.o..
> git tree:       upstream
> console output: <https://syzkaller.appspot.com/x/log.txt?x=14a4ac8c580000>
> kernel config:  <https://syzkaller.appspot.com/x/.config?x=5ba6cef8f153bfeb>
> dashboard link: <https://syzkaller.appspot.com/bug?extid=f1bb7e4ea47ea12b535c>
> compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      <https://syzkaller.appspot.com/x/repro.syz?x=12a4ac8c580000>
> C reproducer:   <https://syzkaller.appspot.com/x/repro.c?x=13fc9c8c580000>
>
> Downloadable assets:
> disk image (non-bootable): <https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-a79a588f.raw.xz>
> vmlinux: <https://storage.googleapis.com/syzbot-assets/c7aa4e6d68b0/vmlinux-a79a588f.xz>
> kernel image: <https://storage.googleapis.com/syzbot-assets/5d71f2c64f29/bzImage-a79a588f.xz>
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+f1bb7e4ea47ea12b535c@syzkaller.appspotmail.com
>
> UBSAN: shift-out-of-bounds in drivers/comedi/drivers/aio_iiro_16.c:180:9
> shift exponent 8550 is too large for 32-bit type ’int’
> CPU: 2 UID: 0 PID: 6096 Comm: syz.0.16 Not tainted 6.16.0-rc4-syzkaller-00308-ga79a588fc176 #0 PREEMPT(full) 
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
> Call Trace:
>  <TASK>
>  __dump_stack lib/dump_stack.c:94 [inline]
>  dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
>  ubsan_epilogue lib/ubsan.c:233 [inline]
>  __ubsan_handle_shift_out_of_bounds+0x27f/0x420 lib/ubsan.c:494
>  aio_iiro_16_attach drivers/comedi/drivers/aio_iiro_16.c:180 [inline]
>  aio_iiro_16_attach.cold+0x19/0x1e drivers/comedi/drivers/aio_iiro_16.c:164
>  comedi_device_attach+0x3b3/0x900 drivers/comedi/drivers.c:996
>  do_devconfig_ioctl+0x1a7/0x580 drivers/comedi/comedi_fops.c:855
>  comedi_unlocked_ioctl+0x15bb/0x2e90 drivers/comedi/comedi_fops.c:2136
>  vfs_ioctl fs/ioctl.c:51 [inline]
>  __do_sys_ioctl fs/ioctl.c:907 [inline]
>  __se_sys_ioctl fs/ioctl.c:893 [inline]
>  __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893
>  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>  do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f3eb858e929
> 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:00007ffc84ea1e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 00007f3eb87b5fa0 RCX: 00007f3eb858e929
> RDX: 0000200000000140 RSI: 0000000040946400 RDI: 0000000000000003
> RBP: 00007f3eb8610b39 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007f3eb87b5fa0 R14: 00007f3eb87b5fa0 R15: 0000000000000003
>  </TASK>
> —[ end trace ]—
>
>
> —
> This report is generated by a bot. It may contain errors.
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>
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#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 66acb1586737