================================================================================
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_xtree.c:371:4
index 19 is out of range for type 'xad_t[18]' (aka 'struct xad[18]')
CPU: 0 PID: 144 Comm: kworker/u4:1 Not tainted 5.15.138-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: writeback wb_workfn (flush-7:2)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 ubsan_epilogue lib/ubsan.c:151 [inline]
 __ubsan_handle_out_of_bounds+0x118/0x140 lib/ubsan.c:282
 xtSearch+0x6dc/0x1ca0 fs/jfs/jfs_xtree.c:371
 xtLookup+0x2c0/0x8e0 fs/jfs/jfs_xtree.c:163
 jfs_get_block+0x2e5/0xe50 fs/jfs/inode.c:218
 __mpage_writepage+0x4f9/0x1c00 fs/mpage.c:564
 write_cache_pages+0xa97/0x1160 mm/page-writeback.c:2255
 mpage_writepages+0x13c/0x2f0 fs/mpage.c:712
 do_writepages+0x481/0x730 mm/page-writeback.c:2364
 __writeback_single_inode+0x15b/0xe30 fs/fs-writeback.c:1630
 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1913
 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1984
 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2089
 wb_check_start_all fs/fs-writeback.c:2211 [inline]
 wb_do_writeback fs/fs-writeback.c:2237 [inline]
 wb_workfn+0x9f4/0x1130 fs/fs-writeback.c:2271
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
================================================================================