REISERFS warning (device loop5): vs-13060 reiserfs_update_sd_size: stat data of object [2 6 0x0 SD] (nlink == 1) not found (pos 1)
==================================================================
BUG: KASAN: use-after-free in leaf_paste_in_buffer+0x1a8/0x9f0 fs/reiserfs/lbalance.c:1017
Write of size 3936 at addr ffff0000f7811140 by task syz.5.1623/8938

CPU: 1 PID: 8938 Comm: syz.5.1623 Not tainted 5.15.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x174/0x1e4 mm/kasan/report.c:451
 kasan_check_range+0x274/0x2b4 mm/kasan/generic.c:189
 memmove+0xb4/0xe8 mm/kasan/shadow.c:55
 leaf_paste_in_buffer+0x1a8/0x9f0 fs/reiserfs/lbalance.c:1017
 leaf_copy_boundary_item+0x96c/0x1a34 fs/reiserfs/lbalance.c:199
 leaf_copy_items fs/reiserfs/lbalance.c:551 [inline]
 leaf_move_items+0xa0c/0x1f7c fs/reiserfs/lbalance.c:726
 leaf_shift_left+0xc8/0x39c fs/reiserfs/lbalance.c:750
 balance_leaf_paste_left_shift fs/reiserfs/do_balan.c:458 [inline]
 balance_leaf_paste_left fs/reiserfs/do_balan.c:592 [inline]
 balance_leaf_left fs/reiserfs/do_balan.c:613 [inline]
 balance_leaf+0x41c0/0xe860 fs/reiserfs/do_balan.c:1409
 do_balance+0x27c/0x790 fs/reiserfs/do_balan.c:1888
 reiserfs_paste_into_item+0x630/0x744 fs/reiserfs/stree.c:2159
 reiserfs_get_block+0x1820/0x3fd0 fs/reiserfs/inode.c:1077
 __block_write_begin_int+0x3ec/0x1608 fs/buffer.c:2012
 __block_write_begin+0x40/0x54 fs/buffer.c:2062
 reiserfs_write_begin+0x3c8/0x654 fs/reiserfs/inode.c:2790
 pagecache_write_begin+0xa0/0xc0 mm/filemap.c:3608
 generic_cont_expand_simple+0x12c/0x208 fs/buffer.c:2362
 reiserfs_setattr+0x37c/0xd94 fs/reiserfs/inode.c:3319
 notify_change+0xa34/0xcf8 fs/attr.c:505
 do_truncate+0x1c0/0x28c fs/open.c:65
 do_sys_ftruncate+0x288/0x31c fs/open.c:193
 __do_sys_ftruncate fs/open.c:204 [inline]
 __se_sys_ftruncate fs/open.c:202 [inline]
 __arm64_sys_ftruncate+0x60/0x74 fs/open.c:202
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

The buggy address belongs to the page:
page:00000000c7e0c51b refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x137811
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003803408 fffffc0003de0408 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000f7811000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f7811080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000f7811100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff0000f7811180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f7811200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
Unable to handle kernel write to read-only memory at virtual address ffff000161a20000
Mem abort info:
  ESR = 0x000000009600004f
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x0f: level 3 permission fault
Data abort info:
  ISV = 0, ISS = 0x0000004f
  CM = 0, WnR = 1
swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000001ae186000
[ffff000161a20000] pgd=180000023fff7003, p4d=180000023fff7003, pud=180000023f211003, pmd=180000023f103003, pte=00600001a1a20783
Internal error: Oops: 000000009600004f [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 8938 Comm: syz.5.1623 Tainted: G    B             5.15.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
pstate: a0400005 (NzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __memcpy+0x150/0x260 arch/arm64/lib/memcpy.S:176
lr : memmove+0xc8/0xe8 mm/kasan/shadow.c:58
sp : ffff8000206961a0
x29: ffff8000206961a0 x28: 0000000000000000 x27: ffff0000f7812000
x26: 0000000000000001 x25: 000000000000f140 x24: ffff0000de300a20
x23: ffff8000171b4000 x22: ffff800008cd5cb8 x21: ffff0000f78210d0
x20: ffff0000f7821140 x19: ffffffffffff1ec0 x18: 1fffe0003683318e
x17: 1fffe0003683318e x16: ffff800011b4b268 x15: 0000000000000000
x14: 0000000000000000 x13: a9014ff4a9be7bfd x12: d503233fd65f03c0
x11: d50323bfa8c37bfd x10: f9400bf5a9424ff4 x9 : f94209082a1f03e0
x8 : 531e740990065a08 x7 : 95fbe3a5941290d6 x6 : aa0003f3910003fd
x5 : ffff0000f7812f90 x4 : ffff0000f7813000 x3 : ffff000161a1ffd0
x2 : ffffffff95df2f30 x1 : ffff000161a20080 x0 : ffff0000f78210d0
Call trace:
 __memcpy+0x150/0x260 arch/arm64/lib/memcpy.S:175
 leaf_paste_in_buffer+0x1a8/0x9f0 fs/reiserfs/lbalance.c:1017
 balance_leaf_paste_left_shift fs/reiserfs/do_balan.c:465 [inline]
 balance_leaf_paste_left fs/reiserfs/do_balan.c:592 [inline]
 balance_leaf_left fs/reiserfs/do_balan.c:613 [inline]
 balance_leaf+0x4dc0/0xe860 fs/reiserfs/do_balan.c:1409
 do_balance+0x27c/0x790 fs/reiserfs/do_balan.c:1888
 reiserfs_paste_into_item+0x630/0x744 fs/reiserfs/stree.c:2159
 reiserfs_get_block+0x1820/0x3fd0 fs/reiserfs/inode.c:1077
 __block_write_begin_int+0x3ec/0x1608 fs/buffer.c:2012
 __block_write_begin+0x40/0x54 fs/buffer.c:2062
 reiserfs_write_begin+0x3c8/0x654 fs/reiserfs/inode.c:2790
 pagecache_write_begin+0xa0/0xc0 mm/filemap.c:3608
 generic_cont_expand_simple+0x12c/0x208 fs/buffer.c:2362
 reiserfs_setattr+0x37c/0xd94 fs/reiserfs/inode.c:3319
 notify_change+0xa34/0xcf8 fs/attr.c:505
 do_truncate+0x1c0/0x28c fs/open.c:65
 do_sys_ftruncate+0x288/0x31c fs/open.c:193
 __do_sys_ftruncate fs/open.c:204 [inline]
 __se_sys_ftruncate fs/open.c:202 [inline]
 __arm64_sys_ftruncate+0x60/0x74 fs/open.c:202
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: a9011c66 a9411c26 a9022468 a9422428 (a9032c6a) 
---[ end trace 45d743bb72dc1c1c ]---
----------------
Code disassembly (best guess):
   0:	a9011c66 	stp	x6, x7, [x3, #16]
   4:	a9411c26 	ldp	x6, x7, [x1, #16]
   8:	a9022468 	stp	x8, x9, [x3, #32]
   c:	a9422428 	ldp	x8, x9, [x1, #32]
* 10:	a9032c6a 	stp	x10, x11, [x3, #48] <-- trapping instruction