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:539:39 shift exponent 185 is too large for 32-bit type 'unsigned int' CPU: 0 UID: 0 PID: 488 Comm: syz.2.18 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x107/0x180 lib/dump_stack.c:120 dump_stack+0x15/0x1c lib/dump_stack.c:129 ubsan_epilogue+0xe/0x40 lib/ubsan.c:233 __ubsan_handle_shift_out_of_bounds+0x382/0x420 lib/ubsan.c:494 exfat_read_boot_sector fs/exfat/super.c:539 [inline] __exfat_fill_super fs/exfat/super.c:596 [inline] exfat_fill_super+0x261e/0x2a00 fs/exfat/super.c:671 get_tree_bdev_flags+0x403/0x4c0 fs/super.c:1697 get_tree_bdev+0x1f/0x30 fs/super.c:1720 exfat_get_tree+0x1c/0x30 fs/exfat/super.c:734 vfs_get_tree+0x9d/0x290 fs/super.c:1757 fc_mount fs/namespace.c:1209 [inline] do_new_mount_fc fs/namespace.c:3652 [inline] do_new_mount+0x2fe/0xa00 fs/namespace.c:3728 path_mount+0x671/0xfc0 fs/namespace.c:4038 do_mount fs/namespace.c:4051 [inline] __do_sys_mount fs/namespace.c:4240 [inline] __se_sys_mount+0x363/0x3e0 fs/namespace.c:4217 __x64_sys_mount+0xbf/0xf0 fs/namespace.c:4217 x64_sys_call+0x2c8e/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x5e/0xdb0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f04d4d90e6a 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:00007f04d5ce1e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f04d5ce1ef0 RCX: 00007f04d4d90e6a RDX: 0000200000000000 RSI: 0000200000000240 RDI: 00007f04d5ce1eb0 RBP: 0000200000000000 R08: 00007f04d5ce1ef0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000240 R13: 00007f04d5ce1eb0 R14: 00000000000014fe R15: 0000200000000600 ---[ end trace ]--- exfat: block size(33554432) > page size(4096) not supported by filesystem exFAT-fs (loop2): unable to set blocksize 33554432 exFAT-fs (loop2): failed to read boot sector exFAT-fs (loop2): failed to recognize exfat type