================================================================================ 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: 1203 Comm: kworker/u4:4 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: writeback wb_workfn (flush-7:1) Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 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+0xa70/0x1000 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:2277 mpage_writepages+0x13c/0x2f0 fs/mpage.c:712 do_writepages+0x481/0x730 mm/page-writeback.c:2386 __writeback_single_inode+0x15b/0xe30 fs/fs-writeback.c:1647 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930 wb_writeback+0x451/0xc50 fs/fs-writeback.c:2104 wb_do_writeback fs/fs-writeback.c:2247 [inline] wb_workfn+0x46c/0x1130 fs/fs-writeback.c:2288 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 ================================================================================