REISERFS warning (device loop4): vs-13060 reiserfs_update_sd_size: stat data of object [2 6 0x0 SD] (nlink == 1) not found (pos 1)
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BUG: KASAN: use-after-free in leaf_paste_in_buffer+0x1a8/0x9f0 fs/reiserfs/lbalance.c:1017
Write of size 3936 at addr ffff0000f137e140 by task syz.4.92/4682

CPU: 0 PID: 4682 Comm: syz.4.92 Not tainted 6.1.118-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x174/0x4c0 mm/kasan/report.c:395
 kasan_report+0xd4/0x130 mm/kasan/report.c:495
 kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:189
 memmove+0x60/0x90 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/0x788 fs/reiserfs/do_balan.c:1888
 reiserfs_paste_into_item+0x630/0x744 fs/reiserfs/stree.c:2159
 reiserfs_get_block+0x1a20/0x45d8 fs/reiserfs/inode.c:1069
 __block_write_begin_int+0x340/0x13b4 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+0x278/0x55c mm/filemap.c:3845
 __generic_file_write_iter+0x168/0x388 mm/filemap.c:3973
 generic_file_write_iter+0xb8/0x2b4 mm/filemap.c:4005
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x610/0x91c fs/read_write.c:584
 ksys_pwrite64 fs/read_write.c:699 [inline]
 __do_sys_pwrite64 fs/read_write.c:709 [inline]
 __se_sys_pwrite64 fs/read_write.c:706 [inline]
 __arm64_sys_pwrite64+0x188/0x220 fs/read_write.c:706
 __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+0x58/0x168 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:000000003312782b refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x13137e
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003c40688 fffffc0003cd8908 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000f137e000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f137e080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000f137e100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff0000f137e180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f137e200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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