NILFS (loop0): mounting unchecked fs
NILFS (loop0): recovery complete
NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds
REISERFS (device loop2): Using rupasov hash to sort names
==================================================================
BUG: KASAN: out-of-bounds in memmove include/linux/string.h:387 [inline]
BUG: KASAN: out-of-bounds in leaf_paste_entries+0x421/0x9b0 fs/reiserfs/lbalance.c:1369
Read of size 18446744073709551571 at addr ffff88804bbe3fe1 by task syz-executor.2/20321

CPU: 1 PID: 20321 Comm: syz-executor.2 Not tainted 4.14.209-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351
 kasan_report+0x6f/0x7b mm/kasan/report.c:409
 memmove+0x20/0x50 mm/kasan/kasan.c:293
 memmove include/linux/string.h:387 [inline]
 leaf_paste_entries+0x421/0x9b0 fs/reiserfs/lbalance.c:1369
 balance_leaf_finish_node_paste_dirent fs/reiserfs/do_balan.c:1306 [inline]
 balance_leaf_finish_node_paste fs/reiserfs/do_balan.c:1332 [inline]
 balance_leaf_finish_node fs/reiserfs/do_balan.c:1375 [inline]
 balance_leaf+0x8298/0xbaa0 fs/reiserfs/do_balan.c:1463
 do_balance+0x27e/0x630 fs/reiserfs/do_balan.c:1899
 reiserfs_paste_into_item+0x569/0x6f0 fs/reiserfs/stree.c:2142
 reiserfs_add_entry+0x7d3/0xbc0 fs/reiserfs/namei.c:566
 reiserfs_mkdir+0x5ca/0x8b0 fs/reiserfs/namei.c:858
 create_privroot fs/reiserfs/xattr.c:880 [inline]
 reiserfs_xattr_init+0x393/0xa49 fs/reiserfs/xattr.c:1002
 reiserfs_fill_super+0x1b18/0x28be fs/reiserfs/super.c:2180
 mount_bdev+0x2b3/0x360 fs/super.c:1134
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2549 [inline]
 do_mount+0xe53/0x2a00 fs/namespace.c:2879
 SYSC_mount fs/namespace.c:3095 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3072
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x46090a
RSP: 002b:00007f90b9f6aa88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f90b9f6ab20 RCX: 000000000046090a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f90b9f6aae0
RBP: 00007f90b9f6aae0 R08: 00007f90b9f6ab20 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020011200

The buggy address belongs to the page:
page:ffffea00012ef8c0 count:3 mapcount:0 mapping:ffff8880906e7c68 index:0x2013
flags: 0xfff00000001044(referenced|active|private)
raw: 00fff00000001044 ffff8880906e7c68 0000000000002013 00000003ffffffff
raw: dead000000000100 dead000000000200 ffff888061112150 ffff88823b3201c0
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff88823b3201c0

Memory state around the buggy address:
 ffff88804bbe3e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804bbe3f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804bbe3f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                       ^
 ffff88804bbe4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804bbe4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================