loop0: detected capacity change from 0 to 32770
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/super-io.c:652:18
shift exponent 255 is too large for 32-bit type 'int'
CPU: 0 PID: 5106 Comm: syz-executor.0 Not tainted 6.9.0-rc6-syzkaller-00290-gb9158815de52 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
 read_one_super+0xe18/0x3a10 fs/bcachefs/super-io.c:652
 __bch2_read_super+0x65a/0x1460 fs/bcachefs/super-io.c:750
 bch2_fs_open+0x246/0xdf0 fs/bcachefs/super.c:2049
 bch2_mount+0x71d/0x1320 fs/bcachefs/fs.c:1903
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2a0 fs/super.c:1779
 do_new_mount+0x2be/0xb40 fs/namespace.c:3352
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3a8e27f3aa
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3a8ef6cef8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3a8ef6cf80 RCX: 00007f3a8e27f3aa
RDX: 0000000020005d80 RSI: 0000000020005dc0 RDI: 00007f3a8ef6cf40
RBP: 0000000020005d80 R08: 00007f3a8ef6cf80 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020005dc0
R13: 00007f3a8ef6cf40 R14: 0000000000005d5e R15: 0000000020005e40
 </TASK>
---[ end trace ]---