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BUG: KASAN: out-of-bounds in leaf_copy_items_entirely+0xa36/0xee0 fs/reiserfs/lbalance.c:379
Read of size 18446744073709490108 at addr ffff88805fd6b044 by task syz.1.634/8588

CPU: 0 PID: 8588 Comm: syz.1.634 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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
 memmove+0x25/0x60 mm/kasan/shadow.c:54
 leaf_copy_items_entirely+0xa36/0xee0 fs/reiserfs/lbalance.c:379
 leaf_copy_items fs/reiserfs/lbalance.c:603 [inline]
 leaf_move_items+0x115d/0x28a0 fs/reiserfs/lbalance.c:726
 leaf_shift_right+0x2a/0xe0 fs/reiserfs/lbalance.c:803
 balance_leaf_paste_right_whole fs/reiserfs/do_balan.c:846 [inline]
 balance_leaf_paste_right fs/reiserfs/do_balan.c:900 [inline]
 balance_leaf_right fs/reiserfs/do_balan.c:916 [inline]
 balance_leaf+0x49e1/0x12510 fs/reiserfs/do_balan.c:1415
 do_balance+0x309/0x8f0 fs/reiserfs/do_balan.c:1888
 reiserfs_paste_into_item+0x73b/0x880 fs/reiserfs/stree.c:2159
 reiserfs_get_block+0x226a/0x5390 fs/reiserfs/inode.c:1077
 __block_write_begin_int+0x60b/0x1650 fs/buffer.c:2012
 reiserfs_write_begin+0x346/0x810 fs/reiserfs/inode.c:2790
 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2174 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xacd/0xe50 fs/read_write.c:594
 ksys_write+0x1a2/0x2c0 fs/read_write.c:647
 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: 0033:0x7f3287d08d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3285b79038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f3287ef8fa0 RCX: 00007f3287d08d29
RDX: 000000000000000b RSI: 00000000200002c0 RDI: 0000000000000004
RBP: 00007f3287d84b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3287ef8fa0 R15: 00007ffd13fc5ad8
 </TASK>

The buggy address belongs to the page:
page:ffffea00017f5ac0 refcount:1 mapcount:0 mapping:ffff8880595fb510 index:0x598 pfn:0x5fd6b
memcg:ffff888020754000
aops:shmem_aops ino:51b dentry name:"memfd:syzkaller"
flags: 0xfff0000008001e(referenced|uptodate|dirty|lru|swapbacked|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff0000008001e ffffea0001c52a08 ffffea00015d08c8 ffff8880595fb510
raw: 0000000000000598 0000000000000000 00000001ffffffff ffff888020754000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 8561, ts 261647245265, free_ts 260424879584
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5465
 alloc_pages_vma+0x39a/0x800 mm/mempolicy.c:2146
 shmem_alloc_page mm/shmem.c:1586 [inline]
 shmem_alloc_and_acct_page+0x4d1/0xd10 mm/shmem.c:1611
 shmem_getpage_gfp+0x17b1/0x3190 mm/shmem.c:1906
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_write_begin+0xce/0x1a0 mm/shmem.c:2474
 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2174 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xacd/0xe50 fs/read_write.c:594
 ksys_write+0x1a2/0x2c0 fs/read_write.c:647
 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
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
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:338
 exit_mmap+0x3cd/0x620 mm/mmap.c:3206
 __mmput+0x112/0x3b0 kernel/fork.c:1127
 exit_mm+0x688/0x7f0 kernel/exit.c:550
 do_exit+0x626/0x2480 kernel/exit.c:861
 do_group_exit+0x144/0x310 kernel/exit.c:996
 get_signal+0xc66/0x14e0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 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
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Memory state around the buggy address:
 ffff88805fd6af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805fd6af80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805fd6b000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                           ^
 ffff88805fd6b080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805fd6b100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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