REISERFS warning (device loop0): 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+0x66c/0xa14 fs/reiserfs/lbalance.c:-1
Write of size 4048 at addr ffff0000ea5b9030 by task syz.0.17/4469

CPU: 1 PID: 4469 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0x100 mm/kasan/report.c:524
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x260/0x2a0 mm/kasan/generic.c:189
 memcpy+0x60/0x90 mm/kasan/shadow.c:66
 leaf_paste_in_buffer+0x66c/0xa14 fs/reiserfs/lbalance.c:-1
 balance_leaf_paste_left_whole fs/reiserfs/do_balan.c:564 [inline]
 balance_leaf_paste_left fs/reiserfs/do_balan.c:594 [inline]
 balance_leaf_left fs/reiserfs/do_balan.c:613 [inline]
 balance_leaf+0x2658/0xd2f4 fs/reiserfs/do_balan.c:1409
 do_balance+0x260/0x774 fs/reiserfs/do_balan.c:1888
 reiserfs_paste_into_item+0x5b4/0x6d0 fs/reiserfs/stree.c:2159
 reiserfs_get_block+0x1444/0x3524 fs/reiserfs/inode.c:1069
 __block_write_begin_int+0x34c/0x13b8 fs/buffer.c:1991
 __block_write_begin+0x7c/0xa0 fs/buffer.c:2041
 reiserfs_write_begin+0x328/0x71c fs/reiserfs/inode.c:2775
 generic_perform_write+0x230/0x4e4 mm/filemap.c:3862
 __generic_file_write_iter+0x130/0x250 mm/filemap.c:3960
 generic_file_write_iter+0xb4/0x2b0 mm/filemap.c:3989
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5ac/0x7c4 fs/read_write.c:584
 ksys_write+0x120/0x210 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:646
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the physical page:
page:0000000022a3bd57 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x12a5b9
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003a96e88 fffffc0003a96e08 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000ea5b8f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000ea5b8f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000ea5b9000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                     ^
 ffff0000ea5b9080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000ea5b9100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
REISERFS panic (device loop0): vs-12195 balance_leaf: CFR not initialized
------------[ cut here ]------------
kernel BUG at fs/reiserfs/prints.c:390!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4469 Comm: syz.0.17 Tainted: G    B              syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : __reiserfs_panic+0x13c/0x140 fs/reiserfs/prints.c:384
lr : __reiserfs_panic+0x13c/0x140 fs/reiserfs/prints.c:384
sp : ffff800020c464c0
x29: ffff800020c46560 x28: ffff800020c46d60 x27: ffff800020c46d78
x26: ffff0000ea5aa027 x25: dfff800000000000 x24: ffff800020c46f00
x23: ffff800020c464e0 x22: ffff800011b5eba0 x21: ffff0000d26d0000
x20: ffff800011b5eb80 x19: ffff800014770cbe x18: ffff800011a5bd40
x17: 1fffe00033eebd7e x16: ffff800008042d90 x15: ffff80001504d000
x14: 0000000000000100 x13: 0000000000000120 x12: 0000000000ff0100
x11: ff0080000830b6e8 x10: 0000000000000000 x9 : 23b48fb416e28800
x8 : 23b48fb416e28800 x7 : 0000000000000004 x6 : ffff8000082532dc
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80000a84818c
x2 : ffff00019f75ed10 x1 : 0000000100000000 x0 : 0000000000000049
Call trace:
 __reiserfs_panic+0x13c/0x140 fs/reiserfs/prints.c:384
 balance_leaf+0xa0a8/0xd2f4 fs/reiserfs/do_balan.c:1439
 do_balance+0x260/0x774 fs/reiserfs/do_balan.c:1888
 reiserfs_paste_into_item+0x5b4/0x6d0 fs/reiserfs/stree.c:2159
 reiserfs_get_block+0x1444/0x3524 fs/reiserfs/inode.c:1069
 __block_write_begin_int+0x34c/0x13b8 fs/buffer.c:1991
 __block_write_begin+0x7c/0xa0 fs/buffer.c:2041
 reiserfs_write_begin+0x328/0x71c fs/reiserfs/inode.c:2775
 generic_perform_write+0x230/0x4e4 mm/filemap.c:3862
 __generic_file_write_iter+0x130/0x250 mm/filemap.c:3960
 generic_file_write_iter+0xb4/0x2b0 mm/filemap.c:3989
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5ac/0x7c4 fs/read_write.c:584
 ksys_write+0x120/0x210 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:646
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 912d80a5 911aa2a1 aa1303e4 97ffe397 (d4210000) 
---[ end trace 0000000000000000 ]---