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BUG: KASAN: use-after-free in leaf_paste_in_buffer+0x631/0xab0
Read of size 48 at addr ffff88806dc64ff0 by task syz-executor.3/5470

CPU: 1 PID: 5470 Comm: syz-executor.3 Not tainted 5.15.158-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 kasan_check_range+0x27e/0x290 mm/kasan/generic.c:189
 memcpy+0x25/0x60 mm/kasan/shadow.c:65
 leaf_paste_in_buffer+0x631/0xab0
 leaf_copy_dir_entries+0x71a/0xc60 fs/reiserfs/lbalance.c:108
 leaf_copy_boundary_item+0xbbe/0x21b0 fs/reiserfs/lbalance.c:168
 leaf_copy_items fs/reiserfs/lbalance.c:551 [inline]
 leaf_move_items+0xcd0/0x28a0 fs/reiserfs/lbalance.c:726
 leaf_shift_left+0xba/0x430 fs/reiserfs/lbalance.c:750
 balance_leaf_when_delete_left fs/reiserfs/do_balan.c:194 [inline]
 balance_leaf_when_delete fs/reiserfs/do_balan.c:272 [inline]
 balance_leaf+0x228e/0x12510 fs/reiserfs/do_balan.c:1393
 do_balance+0x309/0x8f0 fs/reiserfs/do_balan.c:1888
 reiserfs_delete_item+0xc07/0x1030 fs/reiserfs/stree.c:1371
 direct2indirect+0xb23/0x1430 fs/reiserfs/tail_conversion.c:139
 reiserfs_get_block+0x4e84/0x5390 fs/reiserfs/inode.c:957
 __block_write_begin_int+0x60b/0x1650 fs/buffer.c:2012
 __reiserfs_write_begin+0x21c/0x460 fs/reiserfs/inode.c:2850
 reiserfs_xattr_set_handle+0x421/0x10b0 fs/reiserfs/xattr.c:578
 reiserfs_xattr_set+0x44e/0x570 fs/reiserfs/xattr.c:640
 __vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x21d/0x420 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x27e/0x2e0 fs/xattr.c:611
 path_setxattr+0x1bc/0x2a0 fs/xattr.c:630
 __do_sys_lsetxattr fs/xattr.c:653 [inline]
 __se_sys_lsetxattr fs/xattr.c:649 [inline]
 __x64_sys_lsetxattr+0xb4/0xd0 fs/xattr.c:649
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7efd87f30d69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efd864400c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007efd8805f1f0 RCX: 00007efd87f30d69
RDX: 0000000020000040 RSI: 0000000020000040 RDI: 0000000020000080
RBP: 00007efd87f7d49e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001001 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007efd8805f1f0 R15: 00007ffe3c354618
 </TASK>

The buggy address belongs to the page:
page:ffffea0001b71900 refcount:3 mapcount:0 mapping:ffff8881408c88b0 index:0x214 pfn:0x6dc64
memcg:ffff88807388c000
aops:def_blk_aops ino:700003
flags: 0xfff00000002022(referenced|active|private|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000002022 0000000000000000 dead000000000122 ffff8881408c88b0
raw: 0000000000000214 ffff888057c2d488 00000003ffffffff ffff88807388c000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x108c48(GFP_NOFS|__GFP_NOFAIL|__GFP_HARDWALL|__GFP_MOVABLE), pid 5447, ts 144168769159, free_ts 143518666966
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423
 __page_cache_alloc+0xd4/0x4a0 mm/filemap.c:1022
 pagecache_get_page+0xa91/0x1010 mm/filemap.c:1940
 find_or_create_page include/linux/pagemap.h:420 [inline]
 grow_dev_page fs/buffer.c:949 [inline]
 grow_buffers fs/buffer.c:1014 [inline]
 __getblk_slow fs/buffer.c:1041 [inline]
 __getblk_gfp+0x22a/0xaf0 fs/buffer.c:1336
 sb_getblk include/linux/buffer_head.h:361 [inline]
 get_empty_nodes+0x8c1/0xd70 fs/reiserfs/fix_node.c:890
 fix_nodes+0x2615/0x8c70 fs/reiserfs/fix_node.c:2662
 reiserfs_insert_item+0xa7a/0xcb0 fs/reiserfs/stree.c:2240
 indirect2direct+0x697/0xc00 fs/reiserfs/tail_conversion.c:283
 maybe_indirect_to_direct fs/reiserfs/stree.c:1587 [inline]
 reiserfs_cut_from_item+0xba3/0x2560 fs/reiserfs/stree.c:1694
 reiserfs_do_truncate+0xa12/0x15b0 fs/reiserfs/stree.c:1973
 reiserfs_truncate_file+0x638/0xda0 fs/reiserfs/inode.c:2318
 reiserfs_setattr+0xa4d/0xf90 fs/reiserfs/inode.c:3409
 reiserfs_xattr_set_handle+0xb90/0x10b0 fs/reiserfs/xattr.c:607
 reiserfs_xattr_set+0x44e/0x570 fs/reiserfs/xattr.c:640
 __vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page_list+0x1f7/0x8e0 mm/page_alloc.c:3433
 release_pages+0x1bb9/0x1f40 mm/swap.c:963
 __pagevec_release+0x80/0xf0 mm/swap.c:983
 pagevec_release include/linux/pagevec.h:81 [inline]
 shmem_undo_range+0x67a/0x1b50 mm/shmem.c:964
 shmem_truncate_range mm/shmem.c:1063 [inline]
 shmem_evict_inode+0x21b/0xa00 mm/shmem.c:1145
 evict+0x2a4/0x620 fs/inode.c:587
 __dentry_kill+0x436/0x650 fs/dcache.c:582
 dentry_kill+0xbb/0x290
 dput+0xd8/0x1a0 fs/dcache.c:889
 __fput+0x5ec/0x890 fs/file_table.c:288
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86

Memory state around the buggy address:
 ffff88806dc64f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88806dc64f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88806dc65000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88806dc65080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806dc65100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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