------------[ cut here ]------------ UBSAN: shift-out-of-bounds in fs/9p/vfs_super.c:57:22 shift exponent 32 is too large for 32-bit type 'int' CPU: 1 UID: 0 PID: 28115 Comm: syz.8.2985 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 ubsan_epilogue+0xa/0x40 lib/ubsan.c:233 __ubsan_handle_shift_out_of_bounds+0x386/0x410 lib/ubsan.c:494 v9fs_fill_super fs/9p/vfs_super.c:57 [inline] v9fs_get_tree+0x957/0xa90 fs/9p/vfs_super.c:125 vfs_get_tree+0x92/0x2b0 fs/super.c:1752 do_new_mount+0x2a2/0xa30 fs/namespace.c:3810 do_mount fs/namespace.c:4138 [inline] __do_sys_mount fs/namespace.c:4349 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4326 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f504938ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f504a203038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f50495b5fa0 RCX: 00007f504938ebe9 RDX: 0000200000000080 RSI: 00002000000002c0 RDI: 0000000000000000 RBP: 00007f5049411e19 R08: 0000200000000400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f50495b6038 R14: 00007f50495b5fa0 R15: 00007ffd1643a078 ---[ end trace ]---