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BUG: KASAN: use-after-free in memset include/linux/string.h:332 [inline]
BUG: KASAN: use-after-free in __ext4_expand_extra_isize.isra.0+0x10b/0x1c0 fs/ext4/inode.c:5795
Write of size 65503 at addr ffff888199bce3a0 by task syz-executor.5/1853

CPU: 0 PID: 1853 Comm: syz-executor.5 Not tainted 4.14.146+ #0
EXT4-fs error (device sda1): ext4_xattr_set_entry:1605: inode #16697: comm syz-executor.4: corrupted xattr entries
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xca/0x134 lib/dump_stack.c:53
 print_address_description+0x60/0x226 mm/kasan/report.c:187
 __kasan_report.cold+0x1a/0x41 mm/kasan/report.c:316
 memset+0x20/0x40 mm/kasan/common.c:113
 memset include/linux/string.h:332 [inline]
 __ext4_expand_extra_isize.isra.0+0x10b/0x1c0 fs/ext4/inode.c:5795
EXT4-fs error (device sda1): ext4_xattr_set_entry:1605: inode #16523: comm syz-executor.4: corrupted xattr entries
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5847 [inline]
 ext4_mark_inode_dirty+0x471/0x7f0 fs/ext4/inode.c:5923
 ext4_unlink+0xb33/0xfd0 fs/ext4/namei.c:3101
 vfs_unlink2+0x23c/0x470 fs/namei.c:4157
 do_unlinkat+0x327/0x5e0 fs/namei.c:4228
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459777
RSP: 002b:00007fff773209a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000459777
RDX: 00007fff773209c0 RSI: 00007fff773209c0 RDI: 00007fff77320a50
RBP: 00000000000000d1 R08: 0000000000000000 R09: 000000000000000b
R10: 0000000000000006 R11: 0000000000000246 R12: 00007fff77321ae0
R13: 00005555561d5940 R14: 0000000000000000 R15: 00007fff77321ae0

The buggy address belongs to the page:
page:ffffea000666f380 count:2 mapcount:0 mapping:ffff8881d5698f10 index:0x43b
flags: 0x400000000000203a(referenced|dirty|lru|active|private)
raw: 400000000000203a ffff8881d5698f10 000000000000043b 00000002ffffffff
raw: ffffea0006645ae0 ffffea000667e8e0 ffff8881af26f2a0 ffff8881d641aa80
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff8881d641aa80

Memory state around the buggy address:
 ffff888199bcef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888199bcef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888199bcf000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888199bcf080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888199bcf100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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