REISERFS warning:  read_super_block: reiserfs filesystem is deprecated and scheduled to be removed from the kernel in 2025
REISERFS (device loop0): found reiserfs format "3.5" with non-standard journal
REISERFS (device loop0): using ordered data mode
reiserfs: using flush barriers
REISERFS (device loop0): journal params: device loop0, size 15748, journal first block 18, max trans len 1024, max batch 900, max commit age 0, max trans age 30
REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using r5 hash to sort names
REISERFS (device loop0): using 3.5.x disk format
==================================================================
BUG: KASAN: use-after-free in bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
BUG: KASAN: use-after-free in search_by_entry_key+0x81f/0x960 fs/reiserfs/namei.c:165
Read of size 4 at addr ffff88806f9edfc4 by task syz-executor334/3608

CPU: 0 PID: 3608 Comm: syz-executor334 Not tainted 6.1.0-rc2-syzkaller-00062-ga970174d7a10 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15e/0x45d mm/kasan/report.c:395
 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495
 bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
 search_by_entry_key+0x81f/0x960 fs/reiserfs/namei.c:165
 reiserfs_find_entry.part.0+0x139/0xdf0 fs/reiserfs/namei.c:322
 reiserfs_find_entry fs/reiserfs/namei.c:368 [inline]
 reiserfs_lookup+0x24a/0x490 fs/reiserfs/namei.c:368
 __lookup_slow+0x24c/0x460 fs/namei.c:1685
 lookup_one_len+0x16a/0x1a0 fs/namei.c:2711
 reiserfs_lookup_privroot+0x92/0x280 fs/reiserfs/xattr.c:973
 reiserfs_fill_super+0x1a8b/0x2e90 fs/reiserfs/super.c:2192
 mount_bdev+0x34d/0x410 fs/super.c:1400
 legacy_get_tree+0x105/0x220 fs/fs_context.c:610
 vfs_get_tree+0x89/0x2f0 fs/super.c:1530
 do_new_mount fs/namespace.c:3040 [inline]
 path_mount+0x1326/0x1e20 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount fs/namespace.c:3568 [inline]
 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fde794a36ba
Code: 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 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:00007ffc5b0013c8 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffc5b001420 RCX: 00007fde794a36ba
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffc5b0013e0
RBP: 0000000000000003 R08: 00007ffc5b001420 R09: 0000000000000000
R10: 0000000000010001 R11: 0000000000000286 R12: 00007ffc5b0013e0
R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000004
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001be7b40 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x6f9ed
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001be7b88 ffff8880b9a408a0 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 3594, tgid 3594 (sshd), ts 35106391393, free_ts 35119806059
 prep_new_page mm/page_alloc.c:2538 [inline]
 get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4287
 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5554
 __folio_alloc+0x12/0x40 mm/page_alloc.c:5586
 vma_alloc_folio+0xf9/0x780 mm/mempolicy.c:2246
 alloc_page_vma include/linux/gfp.h:270 [inline]
 do_anonymous_page mm/memory.c:4114 [inline]
 handle_pte_fault mm/memory.c:4953 [inline]
 __handle_mm_fault+0x178c/0x3a40 mm/memory.c:5097
 handle_mm_fault+0x1c8/0x780 mm/memory.c:5218
 do_user_addr_fault+0x475/0x1210 arch/x86/mm/fault.c:1428
 handle_page_fault arch/x86/mm/fault.c:1519 [inline]
 exc_page_fault+0x94/0x170 arch/x86/mm/fault.c:1575
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1458 [inline]
 free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1508
 free_unref_page_prepare mm/page_alloc.c:3386 [inline]
 free_unref_page_list+0x172/0xc40 mm/page_alloc.c:3528
 release_pages+0xc86/0x1360 mm/swap.c:1055
 tlb_batch_pages_flush+0xa8/0x1a0 mm/mmu_gather.c:59
 tlb_flush_mmu_free mm/mmu_gather.c:256 [inline]
 tlb_flush_mmu mm/mmu_gather.c:263 [inline]
 tlb_finish_mmu+0x147/0x7e0 mm/mmu_gather.c:363
 unmap_region+0x26a/0x300 mm/mmap.c:2191
 do_mas_align_munmap+0x851/0xee0 mm/mmap.c:2444
 do_mas_munmap+0x26a/0x2b0 mm/mmap.c:2502
 __vm_munmap+0x14f/0x290 mm/mmap.c:2775
 __do_sys_munmap mm/mmap.c:2800 [inline]
 __se_sys_munmap mm/mmap.c:2797 [inline]
 __x64_sys_munmap+0x55/0x80 mm/mmap.c:2797
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff88806f9ede80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806f9edf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88806f9edf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff88806f9ee000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806f9ee080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================