REISERFS warning: green-16003 errcatch_is_left_mergeable: Invalid item type observed, run fsck ASAP
==================================================================
BUG: KASAN: use-after-free in reiserfs_release_objectid+0x527/0x780 fs/reiserfs/objectid.c:165
Read of size 8188 at addr ffff88805d3f1050 by task syz-executor/4195

CPU: 1 PID: 4195 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x235/0x290 mm/kasan/generic.c:189
 memmove+0x25/0x60 mm/kasan/shadow.c:54
 reiserfs_release_objectid+0x527/0x780 fs/reiserfs/objectid.c:165
 remove_save_link+0x2af/0x3e0 fs/reiserfs/super.c:542
 reiserfs_evict_inode+0x3ae/0x4c0 fs/reiserfs/inode.c:91
 evict+0x4c9/0x8d0 fs/inode.c:647
 d_delete_notify include/linux/fsnotify.h:267 [inline]
 vfs_rmdir+0x3b4/0x430 fs/namei.c:4170
 do_rmdir+0x2a1/0x740 fs/namei.c:4218
 __do_sys_unlinkat fs/namei.c:4398 [inline]
 __se_sys_unlinkat fs/namei.c:4392 [inline]
 __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4392
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6753666937
Code: 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 b8 07 01 00 00 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:00007ffe28341df8 EFLAGS: 00000207 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f6753666937
RDX: 0000000000000200 RSI: 00007ffe28342fa0 RDI: 00000000ffffff9c
RBP: 00007f67536fd048 R08: 0000000000008560 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000207 R12: 00007ffe28342fa0
R13: 00007f67536fd048 R14: 0000000000018a56 R15: 00007ffe28345160
 </TASK>

The buggy address belongs to the page:
page:ffffea000174fc40 refcount:2 mapcount:0 mapping:ffff888145d8daf0 index:0x10 pfn:0x5d3f1
memcg:ffff888079c58000
aops:def_blk_aops ino:700003
flags: 0xfff00000022036(referenced|uptodate|lru|active|private|mappedtodisk|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000022036 ffffea00016e51c8 ffffea0001748a08 ffff888145d8daf0
raw: 0000000000000010 ffff8880741c2ae0 00000002ffffffff ffff888079c58000
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 4694, ts 98659631107, free_ts 98612305170
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 __page_cache_alloc+0xce/0x440 mm/filemap.c:1022
 pagecache_get_page+0x9b6/0xf10 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+0x247/0xb60 fs/buffer.c:1336
 __bread_gfp+0x28/0x380 fs/buffer.c:1381
 sb_bread include/linux/buffer_head.h:337 [inline]
 read_super_block+0x91/0x7a0 fs/reiserfs/super.c:1606
 reiserfs_fill_super+0x7a6/0x2440 fs/reiserfs/super.c:1968
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 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+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page_list+0x119/0x820 mm/page_alloc.c:3433
 release_pages+0x186c/0x1be0 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+0x176/0x300 mm/mmu_gather.c:338
 unmap_region+0x344/0x3b0 mm/mmap.c:2669
 __do_munmap+0x9f8/0xdf0 mm/mmap.c:2899
 __vm_munmap+0x140/0x240 mm/mmap.c:2952
 __do_sys_munmap mm/mmap.c:2978 [inline]
 __se_sys_munmap mm/mmap.c:2974 [inline]
 __x64_sys_munmap+0x67/0x70 mm/mmap.c:2974
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Memory state around the buggy address:
 ffff88805d3f1f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805d3f1f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805d3f2000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88805d3f2080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805d3f2100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================