[v5.15] divide error in uvc_queue_setup

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aabd761612db Linux 5.15.215
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=124f3132580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f161cbc9aef65db0
dashboard link: https://syzkaller.appspot.com/bug?extid=97c8e175cc6e7bbed4b1
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f636f56d3662/disk-aabd7616.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f1a46620f40c/vmlinux-aabd7616.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9b78bb48b022/bzImage-aabd7616.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+97c8e1...@syzkaller.appspotmail.com

loop1: detected capacity change from 0 to 2048
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000)
divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 6847 Comm: syz.1.598 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:uvc_queue_setup+0x182/0x2d0 drivers/usb/gadget/function/uvc_queue.c:64
Code: 1f 0f b6 c9 80 f9 02 ba 01 00 00 00 0f 43 d1 0f b6 ca 83 e0 03 44 0f af f8 44 0f af f9 41 ff c4 41 d1 ec 43 8d 44 3c ff 31 d2 <41> f7 f7 83 f8 05 b9 04 00 00 00 0f 43 c8 83 f9 40 bd 40 00 00 00
RSP: 0018:ffffc900014afa00 EFLAGS: 00010246
RAX: 0000000000012bff RBX: ffff88807e6c6b08 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000001c75 RDI: ffff888148c3822e
RBP: 0000000000000020 R08: ffff88807e6c6b70 R09: 1ffff92000295f38
R10: dffffc0000000000 R11: fffff52000295f39 R12: 0000000000012c00
R13: dffffc0000000000 R14: ffff888148c38234 R15: 0000000000000000
FS: 00007f5c663986c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc49cc7bac CR3: 0000000079556000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
vb2_core_reqbufs+0x7b6/0xf30 drivers/media/common/videobuf2/videobuf2-core.c:807
uvcg_alloc_buffers+0x1a/0x70 drivers/usb/gadget/function/uvc_queue.c:183
__video_do_ioctl+0xa10/0xe40 drivers/media/v4l2-core/v4l2-ioctl.c:2977
video_usercopy+0x930/0xf10 drivers/media/v4l2-core/v4l2-ioctl.c:3325
v4l2_ioctl+0x183/0x1d0 drivers/media/v4l2-core/v4l2-dev.c:364
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5c681610d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5c66398028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5c683e9090 RCX: 00007f5c681610d9
RDX: 0000200000000100 RSI: 00000000c0145608 RDI: 000000000000000b
RBP: 00007f5c681f8024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5c683e9128 R14: 00007f5c683e9090 R15: 00007ffdbe441148
</TASK>
Modules linked in:
---[ end trace 372083c1dfa3a3b6 ]---
RIP: 0010:uvc_queue_setup+0x182/0x2d0 drivers/usb/gadget/function/uvc_queue.c:64
Code: 1f 0f b6 c9 80 f9 02 ba 01 00 00 00 0f 43 d1 0f b6 ca 83 e0 03 44 0f af f8 44 0f af f9 41 ff c4 41 d1 ec 43 8d 44 3c ff 31 d2 <41> f7 f7 83 f8 05 b9 04 00 00 00 0f 43 c8 83 f9 40 bd 40 00 00 00
RSP: 0018:ffffc900014afa00 EFLAGS: 00010246
RAX: 0000000000012bff RBX: ffff88807e6c6b08 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000001c75 RDI: ffff888148c3822e
RBP: 0000000000000020 R08: ffff88807e6c6b70 R09: 1ffff92000295f38
R10: dffffc0000000000 R11: fffff52000295f39 R12: 0000000000012c00
R13: dffffc0000000000 R14: ffff888148c38234 R15: 0000000000000000
FS: 00007f5c663986c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f176beffd90 CR3: 0000000079556000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 0f b6 c9 movzbl %cl,%ecx
3: 80 f9 02 cmp $0x2,%cl
6: ba 01 00 00 00 mov $0x1,%edx
b: 0f 43 d1 cmovae %ecx,%edx
e: 0f b6 ca movzbl %dl,%ecx
11: 83 e0 03 and $0x3,%eax
14: 44 0f af f8 imul %eax,%r15d
18: 44 0f af f9 imul %ecx,%r15d
1c: 41 ff c4 inc %r12d
1f: 41 d1 ec shr $1,%r12d
22: 43 8d 44 3c ff lea -0x1(%r12,%r15,1),%eax
27: 31 d2 xor %edx,%edx
* 29: 41 f7 f7 div %r15d <-- trapping instruction
2c: 83 f8 05 cmp $0x5,%eax
2f: b9 04 00 00 00 mov $0x4,%ecx
34: 0f 43 c8 cmovae %eax,%ecx
37: 83 f9 40 cmp $0x40,%ecx
3a: bd 40 00 00 00 mov $0x40,%ebp


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