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UBSAN: array-index-out-of-bounds in fs/jfs/jfs_xtree.c:622:9
index 19 is out of range for type 'xad_t[18]' (aka 'struct xad[18]')
CPU: 1 PID: 39 Comm: kworker/u4:2 Not tainted 6.6.0-syzkaller-06824-g8bc9e6515183 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 ubsan_epilogue lib/ubsan.c:217 [inline]
 __ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348
 xtInsert+0xf45/0xfa0 fs/jfs/jfs_xtree.c:622
 extAlloc+0xa74/0x1000 fs/jfs/jfs_extent.c:145
 jfs_get_block+0x41b/0xe60 fs/jfs/inode.c:248
 __mpage_writepage+0x912/0x1fe0 fs/mpage.c:559
 write_cache_pages+0x827/0x13f0 mm/page-writeback.c:2474
 mpage_writepages+0x107/0x1d0 fs/mpage.c:679
 do_writepages+0x3a6/0x670 mm/page-writeback.c:2553
 __writeback_single_inode+0x155/0xfa0 fs/fs-writeback.c:1625
 writeback_sb_inodes+0x8e3/0x1210 fs/fs-writeback.c:1916
 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1987
 wb_writeback+0x461/0xc60 fs/fs-writeback.c:2094
 wb_check_start_all fs/fs-writeback.c:2220 [inline]
 wb_do_writeback fs/fs-writeback.c:2246 [inline]
 wb_workfn+0x98f/0xff0 fs/fs-writeback.c:2279
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x90f/0x1400 kernel/workqueue.c:2703
 worker_thread+0xa5f/0xff0 kernel/workqueue.c:2784
 kthread+0x2d3/0x370 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
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