==================================================================
BUG: KASAN: out-of-bounds in leaf_paste_entries+0x698/0xb10 fs/reiserfs/lbalance.c:1377
Read of size 18446744073709551593 at addr ffff00013836afa4 by task syz-executor.2/18523

CPU: 0 PID: 18523 Comm: syz-executor.2 Not tainted 6.6.0-rc7-syzkaller-g8de1e7afcc1c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233
 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0x174/0x514 mm/kasan/report.c:475
 kasan_report+0xd8/0x138 mm/kasan/report.c:588
 kasan_check_range+0x254/0x294 mm/kasan/generic.c:187
 __asan_memmove+0x3c/0x84 mm/kasan/shadow.c:94
 leaf_paste_entries+0x698/0xb10 fs/reiserfs/lbalance.c:1377
 balance_leaf_finish_node_paste_dirent fs/reiserfs/do_balan.c:1295 [inline]
 balance_leaf_finish_node_paste fs/reiserfs/do_balan.c:1321 [inline]
 balance_leaf_finish_node fs/reiserfs/do_balan.c:1364 [inline]
 balance_leaf+0xa0d4/0xe860 fs/reiserfs/do_balan.c:1452
 do_balance+0x27c/0x788 fs/reiserfs/do_balan.c:1888
 reiserfs_paste_into_item+0x630/0x744 fs/reiserfs/stree.c:2157
 reiserfs_add_entry+0x8ec/0xca8 fs/reiserfs/namei.c:565
 reiserfs_mkdir+0x588/0x77c fs/reiserfs/namei.c:860
 xattr_mkdir fs/reiserfs/xattr.c:77 [inline]
 create_privroot fs/reiserfs/xattr.c:891 [inline]
 reiserfs_xattr_init+0x2b4/0x638 fs/reiserfs/xattr.c:1007
 reiserfs_fill_super+0x1bfc/0x2028 fs/reiserfs/super.c:2175
 mount_bdev+0x1e8/0x2b4 fs/super.c:1629
 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:662
 vfs_get_tree+0x90/0x288 fs/super.c:1750
 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335
 path_mount+0x590/0xe04 fs/namespace.c:3662
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount fs/namespace.c:3861 [inline]
 __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3861
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595

The buggy address belongs to the physical page:
page:000000004e1afc9d refcount:2 mapcount:0 mapping:000000006dfcdc41 index:0x213 pfn:0x17836a
memcg:ffff0000d1d00000
aops:def_blk_aops ino:700002
flags: 0x5ffc00000008124(referenced|lru|active|private|node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 05ffc00000008124 fffffc00044252c8 ffff0000c7aa2030 ffff0000c149c210
raw: 0000000000000213 ffff000125d3fe80 00000002ffffffff ffff0000d1d00000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff00013836ae80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff00013836af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff00013836af80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                               ^
 ffff00013836b000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff00013836b080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
REISERFS warning: reiserfs-5094 has_valid_deh_location: directory entry location seems wrong *3.5*[2 0 0x65722e01 UNKNOWN], item_len 29662, item_location 2, free_space(entry_count) 37376
REISERFS error (device loop2): vs-5150 search_by_key: invalid format found in block 531. Fsck?
REISERFS (device loop2): Remounting filesystem read-only
REISERFS error (device loop2): vs-13050 reiserfs_update_sd_size: i/o failure occurred trying to update [1 2 0x0 SD] stat data
REISERFS warning (device loop2): jdm-20006 create_privroot: xattrs/ACLs enabled and couldn't find/create .reiserfs_priv. Failing mount.
REISERFS warning: reiserfs-5094 has_valid_deh_location: directory entry location seems wrong *3.5*[2 0 0x65722e01 UNKNOWN], item_len 29662, item_location 2, free_space(entry_count) 37376
REISERFS error (device loop2): vs-5150 search_by_key: invalid format found in block 531. Fsck?
REISERFS error (device loop2): zam-7001 reiserfs_find_entry: io error