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REISERFS warning (device loop0): vs-13060 reiserfs_update_sd_size: stat data of object [1 2 0x0 UNKNOWN] (nlink == 1) not found (pos 2)
REISERFS warning: green-16003 errcatch_is_left_mergeable: Invalid item type observed, run fsck ASAP
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BUG: KASAN: use-after-free in reiserfs_release_objectid+0x572/0x810 fs/reiserfs/objectid.c:165
Read of size 8188 at addr ffff88805d849050 by task syz.0.21/5927

CPU: 0 PID: 5927 Comm: syz.0.21 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:468
 kasan_report+0x117/0x150 mm/kasan/report.c:581
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x241/0x290 mm/kasan/generic.c:187
 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94
 reiserfs_release_objectid+0x572/0x810 fs/reiserfs/objectid.c:165
 remove_save_link+0x2b3/0x3e0 fs/reiserfs/super.c:542
 reiserfs_evict_inode+0x3b2/0x4c0 fs/reiserfs/inode.c:91
 evict+0x4ca/0x8d0 fs/inode.c:705
 __dentry_kill+0x431/0x650 fs/dcache.c:611
 dentry_kill+0xb8/0x290 fs/dcache.c:-1
 dput+0xfe/0x1e0 fs/dcache.c:918
 do_renameat2+0x8f9/0xce0 fs/namei.c:5035
 __do_sys_renameat2 fs/namei.c:5066 [inline]
 __se_sys_renameat2 fs/namei.c:5063 [inline]
 __x64_sys_renameat2+0xd2/0xe0 fs/namei.c:5063
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faff779c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd9266a5d8 EFLAGS: 00000246 ORIG_RAX: 000000000000013c
RAX: ffffffffffffffda RBX: 00007faff7a15fa0 RCX: 00007faff779c819
RDX: 0000000000000004 RSI: 0000200000000000 RDI: 0000000000000004
RBP: 00007faff7832c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faff7a15fac R14: 00007faff7a15fa0 R15: 00007faff7a15fa0
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001761240 refcount:2 mapcount:0 mapping:ffff8880200c41f8 index:0x10 pfn:0x5d849
memcg:ffff88802f37c000
aops:def_blk_aops ino:700000
flags: 0xfff5800002822c(referenced|uptodate|lru|workingset|private|mappedtodisk|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff5800002822c ffffea0001760f08 ffffea0001771208 ffff8880200c41f8
raw: 0000000000000010 ffff88806014fae0 00000002ffffffff ffff88802f37c000
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 5927, tgid 5927 (syz.0.21), ts 97309884768, free_ts 97289270610
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581
 prep_new_page mm/page_alloc.c:1588 [inline]
 get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220
 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500
 folio_alloc+0x1e/0x30 mm/mempolicy.c:2289
 filemap_alloc_folio+0xdf/0x490 mm/filemap.c:1004
 __filemap_get_folio+0x3ea/0xbb0 mm/filemap.c:1962
 grow_dev_page fs/buffer.c:1058 [inline]
 grow_buffers fs/buffer.c:1118 [inline]
 __getblk_slow fs/buffer.c:1145 [inline]
 __getblk_gfp+0x223/0x660 fs/buffer.c:1439
 __bread_gfp+0x2a/0x330 fs/buffer.c:1473
 sb_bread include/linux/buffer_head.h:326 [inline]
 read_super_block+0x91/0x7c0 fs/reiserfs/super.c:1604
 reiserfs_fill_super+0x7ad/0x23b0 fs/reiserfs/super.c:1966
 mount_bdev+0x221/0x2d0 fs/super.c:1643
 legacy_get_tree+0xea/0x180 fs/fs_context.c:662
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3386
 do_mount fs/namespace.c:3726 [inline]
 __do_sys_mount fs/namespace.c:3935 [inline]
 __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1181 [inline]
 free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365
 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2504
 release_pages+0x1f7a/0x2200 mm/swap.c:1022
 tlb_batch_pages_flush mm/mmu_gather.c:99 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:294 [inline]
 tlb_flush_mmu+0x379/0x510 mm/mmu_gather.c:301
 tlb_finish_mmu+0xf9/0x220 mm/mmu_gather.c:425
 unmap_region+0x312/0x370 mm/mmap.c:2349
 do_vmi_align_munmap+0x10dc/0x16d0 mm/mmap.c:2592
 do_vmi_munmap+0x252/0x2d0 mm/mmap.c:2660
 __vm_munmap+0x1a2/0x3c0 mm/mmap.c:2961
 __do_sys_munmap mm/mmap.c:2978 [inline]
 __se_sys_munmap mm/mmap.c:2975 [inline]
 __x64_sys_munmap+0x60/0x70 mm/mmap.c:2975
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88805d849f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805d849f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805d84a000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88805d84a080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805d84a100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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