REISERFS (device loop5): journal params: device loop5, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop5): checking transaction log (loop5)
REISERFS (device loop5): Using r5 hash to sort names
REISERFS (device loop5): Created .reiserfs_priv - reserved for xattr storage.
==================================================================
BUG: KASAN: use-after-free in memcpy include/linux/string.h:377 [inline]
BUG: KASAN: use-after-free in leaf_paste_in_buffer+0xa27/0xc20 fs/reiserfs/lbalance.c:1043
Read of size 80 at addr ffff888042bc5fe0 by task syz-executor.5/10358

CPU: 1 PID: 10358 Comm: syz-executor.5 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report+0x8f/0xa0 mm/kasan/report.c:412
 memcpy+0x20/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:377 [inline]
 leaf_paste_in_buffer+0xa27/0xc20 fs/reiserfs/lbalance.c:1043
 leaf_copy_dir_entries.isra.0+0x7f3/0x980 fs/reiserfs/lbalance.c:108
 leaf_copy_boundary_item fs/reiserfs/lbalance.c:168 [inline]
 leaf_copy_items fs/reiserfs/lbalance.c:551 [inline]
 leaf_move_items+0x17f6/0x3b60 fs/reiserfs/lbalance.c:726
 leaf_shift_left+0xa0/0x380 fs/reiserfs/lbalance.c:750
 balance_leaf_left fs/reiserfs/do_balan.c:622 [inline]
 balance_leaf+0x2fb8/0xca70 fs/reiserfs/do_balan.c:1420
 do_balance+0x30a/0x760 fs/reiserfs/do_balan.c:1899
 reiserfs_insert_item+0xbf3/0x1010 fs/reiserfs/stree.c:2271
 reiserfs_new_inode+0xe51/0x2180 fs/reiserfs/inode.c:2064
 reiserfs_create+0x346/0x720 fs/reiserfs/namei.c:667
 lookup_open+0x893/0x1a20 fs/namei.c:3235
 do_last fs/namei.c:3327 [inline]
 path_openat+0x1094/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fa74a3cc0d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa74893e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa74a4ebf80 RCX: 00007fa74a3cc0d9
RDX: 0000000000000241 RSI: 0000000020000000 RDI: ffffffffffffff9c
RBP: 00007fa74a427ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff4fbd692f R14: 00007fa74893e300 R15: 0000000000022000

The buggy address belongs to the page:
page:ffffea00010af140 count:3 mapcount:0 mapping:ffff88808e442ca0 index:0x214
flags: 0xfff00000001044(referenced|active|private)
raw: 00fff00000001044 dead000000000100 dead000000000200 ffff88808e442ca0
raw: 0000000000000214 ffff8880461c11f8 00000003ffffffff ffff8880b59f68c0
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff8880b59f68c0

Memory state around the buggy address:
 ffff888042bc5f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888042bc5f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888042bc6000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888042bc6080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888042bc6100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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