loop1: 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: 19442 Comm: syz.1.4359 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:233 [inline] __ubsan_handle_shift_out_of_bounds+0x27f/0x420 lib/ubsan.c:494 befs_check_sb.cold+0x19/0x6f fs/befs/super.c:96 befs_fill_super+0x512/0xc90 fs/befs/linuxvfs.c:841 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1692 vfs_get_tree+0x8e/0x340 fs/super.c:1815 do_new_mount fs/namespace.c:3808 [inline] path_mount+0x1513/0x2000 fs/namespace.c:4123 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount fs/namespace.c:4324 [inline] __x64_sys_mount+0x28d/0x310 fs/namespace.c:4324 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efdac39066a 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:00007efdad244e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007efdad244ef0 RCX: 00007efdac39066a RDX: 0000200000000040 RSI: 0000200000000000 RDI: 00007efdad244eb0 RBP: 0000200000000040 R08: 00007efdad244ef0 R09: 0000000000800001 R10: 0000000000800001 R11: 0000000000000246 R12: 0000200000000000 R13: 00007efdad244eb0 R14: 0000000000009e17 R15: 0000200000000080 ---[ end trace ]---