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BUG: KASAN: use-after-free in memset include/linux/string.h:329 [inline]
BUG: KASAN: use-after-free in __ext4_expand_extra_isize.isra.0+0x10b/0x1c0 fs/ext4/inode.c:5787
Write of size 13255 at addr ffff8881ae21e0a0 by task syz-executor5/8848

CPU: 0 PID: 8848 Comm: syz-executor5 Not tainted 4.14.98+ #6
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x10e lib/dump_stack.c:53
 print_address_description+0x60/0x226 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0x88/0x2a5 mm/kasan/report.c:393

The buggy address belongs to the page:
page:ffffea0006b88780 count:2 mapcount:0 mapping:ffff8881d9ea8950 index:0x44c
flags: 0x4000000000001074(referenced|dirty|lru|active|private)
raw: 4000000000001074 ffff8881d9ea8950 000000000000044c 00000002ffffffff
raw: ffffea0006716be0 ffffea0006b73660 ffff8881ae55f888 ffff8881da81aa80
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff8881da81aa80

Memory state around the buggy address:
 ffff8881ae21ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881ae21ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881ae220000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8881ae220080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881ae220100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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