syzbot

loop3: detected capacity change from 0 to 32799
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UBSAN: shift-out-of-bounds in fs/bcachefs/super-io.c:652:18
shift exponent 32 is too large for 32-bit type 'int'
CPU: 1 PID: 7180 Comm: syz-executor245 Not tainted 6.9.0-rc6-syzkaller-g78186bd77b47 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:317
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:114
 dump_stack+0x1c/0x28 lib/dump_stack.c:123
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x2f4/0x36c lib/ubsan.c:468
 read_one_super+0xab8/0x2614 fs/bcachefs/super-io.c:652
 __bch2_read_super+0x714/0x10a8 fs/bcachefs/super-io.c:750
 bch2_read_super+0x38/0x4c fs/bcachefs/super-io.c:842
 bch2_fs_open+0x1e0/0xb64 fs/bcachefs/super.c:2049
 bch2_mount+0x558/0xe10 fs/bcachefs/fs.c:1903
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:662
 vfs_get_tree+0x90/0x288 fs/super.c:1779
 do_new_mount+0x278/0x900 fs/namespace.c:3352
 path_mount+0x590/0xe04 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3875
 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
---[ end trace ]---
bcachefs (/dev/loop3): error reading default superblock: Invalid superblock: too big (got 4696 bytes, layout max 2199023255552)
bcachefs (/dev/loop3): error reading superblock: Not a bcachefs superblock (got magic 00000000-0000-0000-0000-000000000000)Not a bcachefs superblock (got magic 00000000-0000-0000-0000-000000000000)