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UBSAN: array-index-out-of-bounds in fs/jfs/jfs_xtree.c:633:9
index 19 is out of range for type 'xad_t[18]' (aka 'struct xad[18]')
CPU: 1 PID: 2612 Comm: kworker/u4:6 Not tainted 5.15.120-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
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
 xtInsert+0xf41/0xfa0 fs/jfs/jfs_xtree.c:633
 extAlloc+0xa60/0x1010 fs/jfs/jfs_extent.c:148
 jfs_get_block+0x417/0xe50 fs/jfs/inode.c:258
 __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:1625
 writeback_sb_inodes+0xbf0/0x1a50 fs/fs-writeback.c:1908
 wb_writeback+0x451/0xc50 fs/fs-writeback.c:2082
 wb_do_writeback fs/fs-writeback.c:2225 [inline]
 wb_workfn+0x46c/0x1130 fs/fs-writeback.c:2266
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2307
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2454
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
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