------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:1598:11
index 27 is out of range for type 'struct lv[20]'
CPU: 1 UID: 0 PID: 8501 Comm: syz.9.456 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 ubsan_epilogue+0xa/0x30
 __ubsan_handle_out_of_bounds+0xe8/0xf0
 dtSplitPage+0x34bc/0x36a0
 dtInsert+0x1080/0x5cb0
 jfs_create+0x730/0xae0
 path_openat+0x133a/0x3830
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x115/0x200
 __x64_sys_creat+0x8f/0xc0
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f825bd9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f825ccef028 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f825c015fa0 RCX: 00007f825bd9ce59
RDX: 0000000000000000 RSI: 0000000000000044 RDI: 00002000000009c0
RBP: 00007f825be32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f825c016038 R14: 00007f825c015fa0 R15: 00007fffc38bac98
 </TASK>
---[ end trace ]---
