REISERFS warning (device loop3): super-6502 reiserfs_getopt: unknown mount option "	ewize=0"
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BUG: KASAN: use-after-free in memset include/linux/string.h:337 [inline]
BUG: KASAN: use-after-free in __ext4_expand_extra_isize+0x16f/0x240 fs/ext4/inode.c:5897
Write of size 58177 at addr ffff8801a2587ba0 by task syz-executor5/14604

CPU: 0 PID: 14604 Comm: syz-executor5 Not tainted 4.20.0-rc1-next-20181109+ #110
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+0x244/0x39d lib/dump_stack.c:113
 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 memset+0x23/0x40 mm/kasan/kasan.c:285
 memset include/linux/string.h:337 [inline]
 __ext4_expand_extra_isize+0x16f/0x240 fs/ext4/inode.c:5897
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5949 [inline]
 ext4_mark_inode_dirty+0x816/0xb10 fs/ext4/inode.c:6025
 ext4_direct_IO_write fs/ext4/inode.c:3839 [inline]
 ext4_direct_IO+0x1a37/0x2220 fs/ext4/inode.c:3901
 generic_file_direct_write+0x275/0x4b0 mm/filemap.c:3043
 __generic_file_write_iter+0x2ff/0x630 mm/filemap.c:3222
 ext4_file_write_iter+0x390/0x1420 fs/ext4/file.c:266
 call_write_iter include/linux/fs.h:1867 [inline]
 do_iter_readv_writev+0x8b0/0xa80 fs/read_write.c:680
 do_iter_write+0x185/0x5f0 fs/read_write.c:959
 vfs_iter_write+0x77/0xb0 fs/read_write.c:972
 iter_file_splice_write+0x90d/0x1050 fs/splice.c:749
 do_splice_from fs/splice.c:851 [inline]
 direct_splice_actor+0x128/0x190 fs/splice.c:1018
 splice_direct_to_actor+0x318/0x8f0 fs/splice.c:973
 do_splice_direct+0x2d4/0x420 fs/splice.c:1061
 do_sendfile+0x62a/0xe20 fs/read_write.c:1439
 __do_sys_sendfile64 fs/read_write.c:1500 [inline]
 __se_sys_sendfile64 fs/read_write.c:1486 [inline]
 __x64_sys_sendfile64+0x1fd/0x250 fs/read_write.c:1486
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f48b2ce5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000006
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000100000001 R11: 0000000000000246 R12: 00007f48b2ce66d4
R13: 00000000004c3c2a R14: 00000000004d63d0 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea00068961c0 count:2 mapcount:0 mapping:ffff8801cd0b9658 index:0x46f
flags: 0x2fffc000000203a(referenced|dirty|lru|active|private)
raw: 02fffc000000203a ffffea0006990208 ffffea0006605888 ffff8801cd0b9658
raw: 000000000000046f ffff8801b6e5c690 00000002ffffffff ffff880184074600
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff880184074600

Memory state around the buggy address:
 ffff8801a2587f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801a2587f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801a2588000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8801a2588080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8801a2588100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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