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BUG: KASAN: use-after-free in __ext4_expand_extra_isize fs/ext4/inode.c:5948 [inline]
BUG: KASAN: use-after-free in ext4_try_to_expand_extra_isize fs/ext4/inode.c:6000 [inline]
BUG: KASAN: use-after-free in ext4_mark_inode_dirty+0x5a5/0x700 fs/ext4/inode.c:6076
Write of size 65503 at addr ffff88807adfa0a0 by task syz-executor.5/10843

CPU: 0 PID: 10843 Comm: syz-executor.5 Not tainted 5.3.0-rc6+ #94
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113
 print_address_description+0x75/0x5b0 mm/kasan/report.c:351
 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:482
 kasan_report+0x26/0x50 mm/kasan/common.c:618
 check_memory_region_inline mm/kasan/generic.c:182 [inline]
 check_memory_region+0x2cf/0x2e0 mm/kasan/generic.c:192
 memset+0x23/0x40 mm/kasan/common.c:105
 __ext4_expand_extra_isize fs/ext4/inode.c:5948 [inline]
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6000 [inline]
 ext4_mark_inode_dirty+0x5a5/0x700 fs/ext4/inode.c:6076
 ext4_unlink+0xc6a/0xf00 fs/ext4/namei.c:3200
 vfs_unlink+0x237/0x580 fs/namei.c:3999
 do_unlinkat+0x36c/0x7a0 fs/namei.c:4063
 __do_sys_unlink fs/namei.c:4110 [inline]
 __se_sys_unlink fs/namei.c:4108 [inline]
 __x64_sys_unlink+0x49/0x50 fs/namei.c:4108
 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4595c7
Code: 00 66 90 b8 58 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 9d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 7d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd771f58e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004595c7
RDX: 00007ffd771f5900 RSI: 00007ffd771f5900 RDI: 00007ffd771f5990
RBP: 0000000000000b0f R08: 0000000000000000 R09: 0000000000000010
R10: 000000000000000a R11: 0000000000000246 R12: 00007ffd771f6a20
R13: 0000555556406940 R14: 0000000000000000 R15: 00007ffd771f6a20

The buggy address belongs to the page:
page:ffffea0001eb7e80 refcount:2 mapcount:0 mapping:ffff888219ea7ad8 index:0x43d
def_blk_aops 
flags: 0x1fffc000000203a(referenced|dirty|lru|active|private)
raw: 01fffc000000203a ffffea0001d06108 ffffea0001d2ce48 ffff888219ea7ad8
raw: 000000000000043d ffff888094b7ae70 00000002ffffffff ffff888051378640
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff888051378640

Memory state around the buggy address:
 ffff88807adfff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807adfff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807ae00000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88807ae00080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88807ae00100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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