[syzbot] [fs?] UBSAN: shift-out-of-bounds in ufs_fill_super

[syzbot <syzbot+5585f47221c0de04168d@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    562bfb501c54 Merge tag 'integrity-v7.2-rc7' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=174453b9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c05be6c9b0d36cb9
dashboard link: https://syzkaller.appspot.com/bug?extid=5585f47221c0de04168d
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 (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-562bfb50.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7580e6506574/vmlinux-562bfb50.xz
kernel image: https://storage.googleapis.com/syzbot-assets/883f7f234497/bzImage-562bfb50.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5585f47221c0de04168d@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 128
ufs: ufs_fill_super(): fs needs fsck
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/ufs/super.c:1177:18
shift exponent 4294967294 is too large for 32-bit type 'int'
CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233
 __ubsan_handle_shift_out_of_bounds+0x36d/0x400 lib/ubsan.c:494
 ufs_fill_super+0x5f8d/0x67e0 fs/ufs/super.c:1177
 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1640
 vfs_get_tree+0x92/0x2a0 fs/super.c:1700
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3765 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3841
 do_mount fs/namespace.c:4174 [inline]
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4367
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c6519e019
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:00007f6c66037fe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f6c65425fa0 RCX: 00007f6c6519e019
RDX: 0000200000004000 RSI: 0000200000003000 RDI: 0000200000000040
RBP: 00007f6c6523500c R08: 0000200000005000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6c65426038 R14: 00007f6c65425fa0 R15: 00007ffd05bb6728
 </TASK>
---[ end trace ]---


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