loop4: detected capacity change from 0 to 32768
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:2260:2
index 776192 is out of range for type 's64[128]' (aka 'long long[128]')
CPU: 0 UID: 0 PID: 7627 Comm: syz.4.180 Not tainted 6.14.0-syzkaller-gd6b13dbd03b7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_out_of_bounds+0xf8/0x148 lib/ubsan.c:429
 dbAllocBits+0x8dc/0x908 fs/jfs/jfs_dmap.c:2260
 dbAllocDmap fs/jfs/jfs_dmap.c:2037 [inline]
 dbAllocNear+0x224/0x334 fs/jfs/jfs_dmap.c:1258
 dbAlloc+0x8b4/0xb68 fs/jfs/jfs_dmap.c:843
 diNewExt+0x7c0/0x2904 fs/jfs/jfs_imap.c:2261
 diAllocExt fs/jfs/jfs_imap.c:1952 [inline]
 diAllocAG+0xa2c/0x1b7c fs/jfs/jfs_imap.c:1669
 diAlloc+0x17c/0x13c8 fs/jfs/jfs_imap.c:1590
 ialloc+0x84/0x790 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x190/0xa08 fs/jfs/namei.c:225
 vfs_mkdir+0x27c/0x410 fs/namei.c:4313
 do_mkdirat+0x250/0x584 fs/namei.c:4336
 __do_sys_mkdirat fs/namei.c:4351 [inline]
 __se_sys_mkdirat fs/namei.c:4349 [inline]
 __arm64_sys_mkdirat+0x8c/0xa4 fs/namei.c:4349
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
---[ end trace ]---
ERROR: (device loop4): dbAlloc: the hint is outside the map

ERROR: (device loop4): remounting filesystem as read-only