loop0: detected capacity change from 0 to 32768
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:2249:2
index 262144 is out of range for type 's64[128]' (aka 'long long[128]')
CPU: 0 UID: 0 PID: 5340 Comm: syz.0.0 Not tainted 6.16.0-rc5-syzkaller-00193-g40f92e79b0aa #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x40 lib/ubsan.c:233
 __ubsan_handle_out_of_bounds+0xe9/0xf0 lib/ubsan.c:455
 dbAllocBits+0xa07/0xa60 fs/jfs/jfs_dmap.c:2249
 dbAllocDmap fs/jfs/jfs_dmap.c:2026 [inline]
 dbAllocNear+0x2aa/0x3d0 fs/jfs/jfs_dmap.c:1247
 dbAlloc+0x933/0xba0 fs/jfs/jfs_dmap.c:832
 extBalloc fs/jfs/jfs_extent.c:336 [inline]
 extAlloc+0x54a/0xfb0 fs/jfs/jfs_extent.c:127
 jfs_get_block+0x346/0xab0 fs/jfs/inode.c:248
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2151
 block_write_begin+0x8a/0x120 fs/buffer.c:2262
 jfs_write_begin+0x35/0x80 fs/jfs/inode.c:299
 generic_perform_write+0x2c7/0x910 mm/filemap.c:4112
 generic_file_write_iter+0x10f/0x540 mm/filemap.c:4255
 iter_file_splice_write+0x93a/0x1000 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x101/0x160 fs/splice.c:1158
 splice_direct_to_actor+0x5a5/0xcc0 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0x181/0x270 fs/splice.c:1227
 vfs_copy_file_range+0xabc/0x1310 fs/read_write.c:1627
 __do_sys_copy_file_range fs/read_write.c:1677 [inline]
 __se_sys_copy_file_range+0x2fb/0x470 fs/read_write.c:1644
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f18a498e929
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:00007f18a5770038 EFLAGS: 00000246 ORIG_RAX: 0000000000000146
RAX: ffffffffffffffda RBX: 00007f18a4bb5fa0 RCX: 00007f18a498e929
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007f18a4a10b39 R08: 0000000000000100 R09: 0000000000000000
R10: 0000200000000380 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f18a4bb5fa0 R15: 00007ffe0ca681b8
 </TASK>
---[ end trace ]---