REISERFS (device loop0): Using r5 hash to sort names
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
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BUG: KASAN: use-after-free in leaf_paste_in_buffer+0xa2d/0xc30 fs/reiserfs/lbalance.c:1043
Read of size 176 at addr ffff888074deef90 by task syz-executor177/5101

CPU: 1 PID: 5101 Comm: syz-executor177 Not tainted 6.2.0-rc7-syzkaller-00199-g420b2d431d18 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:306 [inline]
 print_report+0x15e/0x45d mm/kasan/report.c:417
 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x141/0x190 mm/kasan/generic.c:189
 memcpy+0x24/0x60 mm/kasan/shadow.c:65
 leaf_paste_in_buffer+0xa2d/0xc30 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+0x16d2/0x3ad0 fs/reiserfs/lbalance.c:726
 leaf_shift_left+0xa4/0x380 fs/reiserfs/lbalance.c:750
 balance_leaf_left fs/reiserfs/do_balan.c:616 [inline]
 balance_leaf+0x3337/0xde40 fs/reiserfs/do_balan.c:1409
 do_balance+0x319/0x810 fs/reiserfs/do_balan.c:1888
 reiserfs_insert_item+0xdb2/0x11b0 fs/reiserfs/stree.c:2261
 reiserfs_get_block+0x1b23/0x4150 fs/reiserfs/inode.c:868
 __block_write_begin_int+0x3bd/0x14b0 fs/buffer.c:1991
 reiserfs_write_begin+0x36e/0xa60 fs/reiserfs/inode.c:2775
 generic_perform_write+0x256/0x570 mm/filemap.c:3772
 __generic_file_write_iter+0x2ae/0x500 mm/filemap.c:3900
 generic_file_write_iter+0xe3/0x350 mm/filemap.c:3932
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x9ed/0xdd0 fs/read_write.c:584
 ksys_write+0x12b/0x250 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3678686ae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc9dfa2828 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000a16e RCX: 00007f3678686ae9
RDX: 000000000000fea7 RSI: 0000000020000280 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000014 R09: 00007ffc9dfa2850
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc9dfa284c
R13: 00007ffc9dfa2880 R14: 00007ffc9dfa2860 R15: 0000000000000011
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001d37b80 refcount:4 mapcount:0 mapping:ffff8880128e49f8 index:0x214 pfn:0x74dee
memcg:ffff888140140000
aops:def_blk_aops ino:700000
flags: 0xfff00000002012(referenced|lru|private|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000002012 ffffea0001d37b08 ffff8880124c4020 ffff8880128e49f8
raw: 0000000000000214 ffff88807446f2b8 00000004ffffffff ffff888140140000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x148c48(GFP_NOFS|__GFP_NOFAIL|__GFP_COMP|__GFP_HARDWALL|__GFP_MOVABLE), pid 5101, tgid 5101 (syz-executor177), ts 41708765700, free_ts 41535316353
 prep_new_page mm/page_alloc.c:2531 [inline]
 get_page_from_freelist+0x119c/0x2ce0 mm/page_alloc.c:4283
 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5549
 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2287
 folio_alloc+0x20/0x70 mm/mempolicy.c:2297
 filemap_alloc_folio+0x362/0x450 mm/filemap.c:972
 __filemap_get_folio+0x32c/0xd80 mm/filemap.c:1966
 pagecache_get_page+0x2e/0x280 mm/folio-compat.c:98
 find_or_create_page include/linux/pagemap.h:612 [inline]
 grow_dev_page fs/buffer.c:946 [inline]
 grow_buffers fs/buffer.c:1011 [inline]
 __getblk_slow+0x1f4/0x1030 fs/buffer.c:1038
 __getblk_gfp+0x72/0x80 fs/buffer.c:1333
 sb_getblk include/linux/buffer_head.h:356 [inline]
 get_empty_nodes+0x519/0x7d0 fs/reiserfs/fix_node.c:890
 fix_nodes+0x1c21/0x8660 fs/reiserfs/fix_node.c:2662
 reiserfs_insert_item+0x7fc/0x11b0 fs/reiserfs/stree.c:2240
 reiserfs_new_inode+0xe55/0x2190 fs/reiserfs/inode.c:2054
 reiserfs_create+0x351/0x730 fs/reiserfs/namei.c:668
 lookup_open.isra.0+0xee7/0x1270 fs/namei.c:3413
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x975/0x2a50 fs/namei.c:3711
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1446 [inline]
 free_pcp_prepare+0x65c/0xc00 mm/page_alloc.c:1496
 free_unref_page_prepare mm/page_alloc.c:3369 [inline]
 free_unref_page_list+0x176/0xcd0 mm/page_alloc.c:3510
 release_pages+0xcb1/0x1330 mm/swap.c:1076
 __pagevec_release+0x77/0xe0 mm/swap.c:1096
 pagevec_release include/linux/pagevec.h:71 [inline]
 folio_batch_release include/linux/pagevec.h:135 [inline]
 shmem_undo_range+0x595/0x1340 mm/shmem.c:947
 shmem_truncate_range mm/shmem.c:1042 [inline]
 shmem_evict_inode+0x32f/0xb60 mm/shmem.c:1151
 evict+0x2ed/0x6b0 fs/inode.c:664
 iput_final fs/inode.c:1747 [inline]
 iput.part.0+0x59b/0x880 fs/inode.c:1773
 iput+0x5c/0x80 fs/inode.c:1763
 dentry_unlink_inode+0x2b1/0x460 fs/dcache.c:401
 __dentry_kill+0x3c0/0x640 fs/dcache.c:607
 dentry_kill fs/dcache.c:733 [inline]
 dput+0x80a/0xdb0 fs/dcache.c:913
 __fput+0x3cc/0xa90 fs/file_table.c:328
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 ptrace_notify+0x118/0x140 kernel/signal.c:2354
 ptrace_report_syscall include/linux/ptrace.h:411 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]
 syscall_exit_work kernel/entry/common.c:251 [inline]
 syscall_exit_to_user_mode_prepare+0x129/0x280 kernel/entry/common.c:278

Memory state around the buggy address:
 ffff888074deef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888074deef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888074def000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888074def080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888074def100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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