==================================================================
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 991 at addr ffff8881988dbea0 by task syz-executor.4/1857

CPU: 1 PID: 1857 Comm: syz-executor.4 Not tainted 4.14.102+ #17
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:ffffea00066236c0 count:2 mapcount:0 mapping:ffff8881d9eb0950 index:0x459
flags: 0x4000000000001074(referenced|dirty|lru|active|private)
raw: 4000000000001074 ffff8881d9eb0950 0000000000000459 00000002ffffffff
raw: ffffea0006616da0 ffffea00065fcfa0 ffff88819c76cd20 ffff8881da81aa80
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff8881da81aa80

Memory state around the buggy address:
 ffff8881988dbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881988dbf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881988dc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8881988dc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881988dc100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
EXT4-fs error (device sda1): ext4_xattr_set_entry:1604: inode #16483: comm syz-executor.1: corrupted xattr entries