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. ================================================================================ UBSAN: shift-out-of-bounds in fs/exfat/super.c:532:38 shift exponent 185 is too large for 32-bit type 'int' CPU: 1 PID: 516 Comm: syz.2.28 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 dump_stack+0x15/0x24 lib/dump_stack.c:113 ubsan_epilogue+0xe/0x40 lib/ubsan.c:151 __ubsan_handle_shift_out_of_bounds+0x37c/0x400 lib/ubsan.c:321 exfat_read_boot_sector fs/exfat/super.c:532 [inline] __exfat_fill_super fs/exfat/super.c:588 [inline] exfat_fill_super+0x2856/0x2c30 fs/exfat/super.c:652 get_tree_bdev+0x447/0x690 fs/super.c:1368 exfat_get_tree+0x1c/0x20 fs/exfat/super.c:724 vfs_get_tree+0x9a/0x270 fs/super.c:1575 do_new_mount+0x25a/0xa20 fs/namespace.c:3078 path_mount+0x659/0xfc0 fs/namespace.c:3408 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x320/0x390 fs/namespace.c:3606 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3606 x64_sys_call+0x65d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f196c19c10a Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f196cfa7e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f196cfa7ee0 RCX: 00007f196c19c10a RDX: 0000200000000000 RSI: 0000200000000240 RDI: 00007f196cfa7ea0 RBP: 0000200000000000 R08: 00007f196cfa7ee0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000240 R13: 00007f196cfa7ea0 R14: 00000000000014fe R15: 0000200000000600 ================================================================================ exFAT-fs (loop2): unable to set blocksize 33554432 exFAT-fs (loop2): failed to read boot sector exFAT-fs (loop2): failed to recognize exfat type