loop0: detected capacity change from 0 to 128 ------------[ cut here ]------------ UBSAN: shift-out-of-bounds in fs/befs/super.c:96:9 shift exponent 2066842816 is too large for 32-bit type 'int' CPU: 1 UID: 0 PID: 6660 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233 __ubsan_handle_shift_out_of_bounds+0x385/0x410 lib/ubsan.c:494 befs_check_sb+0x421/0x4c0 fs/befs/super.c:96 befs_fill_super+0x49b/0xa70 fs/befs/linuxvfs.c:843 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3763 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3839 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4338 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb3b579c18a 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:00007fb3b4dfde58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb3b4dfdee0 RCX: 00007fb3b579c18a RDX: 0000200000000040 RSI: 0000200000000000 RDI: 00007fb3b4dfdea0 RBP: 0000200000000040 R08: 00007fb3b4dfdee0 R09: 0000000000800001 R10: 0000000000800001 R11: 0000000000000246 R12: 0000200000000000 R13: 00007fb3b4dfdea0 R14: 0000000000009e17 R15: 0000200000000080 ---[ end trace ]---