loop1: p5 size 100 extends beyond EOD, truncated
loop1: p6 size 100 extends beyond EOD, truncated
loop1: p7 size 100 extends beyond EOD, truncated
loop1: p8 size 100 extends beyond EOD, truncated
==================================================================
BUG: KASAN: use-after-free in memset include/linux/string.h:329 [inline]
BUG: KASAN: use-after-free in __ext4_expand_extra_isize.isra.13+0x108/0x1b0 fs/ext4/inode.c:5781
Write of size 21770 at addr ffff8881998c88a0 by task syz-executor3/1854

CPU: 1 PID: 1854 Comm: syz-executor3 Not tainted 4.14.87+ #19
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 print_address_description+0x60/0x22b mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409
 memset+0x1f/0x40 mm/kasan/kasan.c:285
 memset include/linux/string.h:329 [inline]
 __ext4_expand_extra_isize.isra.13+0x108/0x1b0 fs/ext4/inode.c:5781
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5833 [inline]
 ext4_mark_inode_dirty+0x46c/0x7e0 fs/ext4/inode.c:5909
 ext4_unlink+0x747/0xeb0 fs/ext4/namei.c:3044
 vfs_unlink2+0x23b/0x470 fs/namei.c:4073
 do_unlinkat+0x467/0x650 fs/namei.c:4144
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4573a7
RSP: 002b:00007ffffb078e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004573a7
RDX: 00007ffffb078e70 RSI: 00007ffffb078e70 RDI: 00007ffffb078f00
RBP: 0000000000000197 R08: 0000000000000000 R09: 000000000000000b
R10: 0000000000000006 R11: 0000000000000246 R12: 00007ffffb079f90
R13: 0000000000c42940 R14: 0000000000000000 R15: 0000000000000003

The buggy address belongs to the page:
page:ffffea0006663200 count:2 mapcount:0 mapping:ffff8881da4170d0 index:0x430
flags: 0x4000000000001074(referenced|dirty|lru|active|private)
raw: 4000000000001074 ffff8881da4170d0 0000000000000430 00000002ffffffff
raw: ffffea00066cdb20 ffffea000666a620 ffff8881cf0f3f18 ffff8881da81aa80
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff8881da81aa80

Memory state around the buggy address:
 ffff8881998c8f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881998c8f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881998c9000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8881998c9080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881998c9100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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