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BUG: KASAN: stack-out-of-bounds in finish_writeback_work.isra.0+0x11b/0x120 fs/fs-writeback.c:168
Read of size 8 at addr ffff8880698a7a90 by task kworker/u4:5/9024

CPU: 0 PID: 9024 Comm: kworker/u4:5 Not tainted 5.4.0-rc1+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:634
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 finish_writeback_work.isra.0+0x11b/0x120 fs/fs-writeback.c:168
 wb_do_writeback fs/fs-writeback.c:2030 [inline]
 wb_workfn+0x34f/0x1220 fs/fs-writeback.c:2070
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the page:
page:ffffea0001a629c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 0000000000000000 ffffffff01a60101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880698a7980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880698a7a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
>ffff8880698a7a80: f1 f1 f1 00 f2 f2 f2 00 00 00 00 00 00 00 00 00
                         ^
 ffff8880698a7b00: f2 f2 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00
 ffff8880698a7b80: 00 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00
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