loop2: detected capacity change from 0 to 256
exFAT-fs (loop2): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
exFAT-fs (loop2): Medium has reported failures. Some data may be lost.
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/exfat/super.c:550:38
shift exponent 185 is too large for 32-bit type 'int'
CPU: 1 UID: 0 PID: 507 Comm: syz.2.23 Not tainted 6.15.0-rc4-syzkaller-00052-g4f79eaa2ceac #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x107/0x170 lib/dump_stack.c:120
 dump_stack+0x15/0x1c lib/dump_stack.c:129
 ubsan_epilogue+0xe/0x40 lib/ubsan.c:231
 __ubsan_handle_shift_out_of_bounds+0x382/0x410 lib/ubsan.c:492
 exfat_read_boot_sector fs/exfat/super.c:550 [inline]
 __exfat_fill_super fs/exfat/super.c:606 [inline]
 exfat_fill_super+0x266e/0x2a50 fs/exfat/super.c:668
 get_tree_bdev_flags+0x3f2/0x4c0 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 exfat_get_tree+0x1c/0x30 fs/exfat/super.c:735
 vfs_get_tree+0x8c/0x280 fs/super.c:1759
 do_new_mount+0x24c/0xa10 fs/namespace.c:3884
 path_mount+0x682/0xfd0 fs/namespace.c:4211
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount+0x362/0x3e0 fs/namespace.c:4412
 __x64_sys_mount+0xbf/0xe0 fs/namespace.c:4412
 x64_sys_call+0xd4e/0x2f60 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x54/0xf0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f9f3e98f90a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f9f3f76ee68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9f3f76eef0 RCX: 00007f9f3e98f90a
RDX: 0000200000000000 RSI: 0000200000000240 RDI: 00007f9f3f76eeb0
RBP: 0000200000000000 R08: 00007f9f3f76eef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000240
R13: 00007f9f3f76eeb0 R14: 00000000000014fe R15: 0000200000000600
 </TASK>
---[ end trace ]---
exFAT-fs (loop2): unable to set blocksize 33554432
exFAT-fs (loop2): failed to read boot sector
exFAT-fs (loop2): failed to recognize exfat type