syzbot

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 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using r5 hash to sort names
==================================================================
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+0x823/0x960 fs/reiserfs/namei.c:165
Read of size 4 at addr ffff888073ef3004 by task syz-executor471/5001

CPU: 0 PID: 5001 Comm: syz-executor471 Not tainted 6.4.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
 print_report mm/kasan/report.c:462 [inline]
 kasan_report+0x11c/0x130 mm/kasan/report.c:572
 bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
 search_by_entry_key+0x823/0x960 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+0x24e/0x610 fs/reiserfs/namei.c:368
 __lookup_slow+0x24c/0x460 fs/namei.c:1690
 lookup_one_len+0x16e/0x1a0 fs/namei.c:2742
 reiserfs_lookup_privroot+0x96/0x210 fs/reiserfs/xattr.c:976
 reiserfs_fill_super+0x1a8d/0x2eb0 fs/reiserfs/super.c:2192
 mount_bdev+0x357/0x420 fs/super.c:1380
 legacy_get_tree+0x109/0x220 fs/fs_context.c:610
 vfs_get_tree+0x8d/0x350 fs/super.c:1510
 do_new_mount fs/namespace.c:3039 [inline]
 path_mount+0x134b/0x1e40 fs/namespace.c:3369
 do_mount fs/namespace.c:3382 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount fs/namespace.c:3568 [inline]
 __x64_sys_mount+0x283/0x300 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3c5049ad2a
Code: 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 f8 03 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffde73026a8 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3c5049ad2a
RDX: 0000000020000140 RSI: 0000000020000340 RDI: 00007ffde73026b0
RBP: 00007ffde73026b0 R08: 00007ffde73026f0 R09: 000000000000111a
R10: 000000000120c083 R11: 0000000000000286 R12: 0000000000000004
R13: 0000555555b802b8 R14: 00007ffde73026f0 R15: 0000000000000000
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001cfbcc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x73ef3
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea0001cfbd08 ffff8880b9843660 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 4967, tgid 4967 (sshd), ts 37292231688, free_ts 37344330974
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1731
 prep_new_page mm/page_alloc.c:1738 [inline]
 get_page_from_freelist+0xf41/0x2c00 mm/page_alloc.c:3502
 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4768
 __folio_alloc+0x16/0x40 mm/page_alloc.c:4800
 vma_alloc_folio+0x155/0x890 mm/mempolicy.c:2240
 do_anonymous_page mm/memory.c:4085 [inline]
 do_pte_missing mm/memory.c:3645 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault+0x224c/0x41c0 mm/memory.c:5089
 handle_mm_fault+0x2af/0x9f0 mm/memory.c:5243
 do_user_addr_fault+0x2ca/0x1210 arch/x86/mm/fault.c:1349
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 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:1302 [inline]
 free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2564
 free_unref_page_list+0xe3/0xa70 mm/page_alloc.c:2705
 release_pages+0xcd8/0x1380 mm/swap.c:1042
 tlb_batch_pages_flush+0xa8/0x1a0 mm/mmu_gather.c:97
 tlb_flush_mmu_free mm/mmu_gather.c:292 [inline]
 tlb_flush_mmu mm/mmu_gather.c:299 [inline]
 tlb_finish_mmu+0x14b/0x7e0 mm/mmu_gather.c:391
 unmap_region+0x23d/0x2d0 mm/mmap.c:2222
 do_vmi_align_munmap+0xe26/0x1580 mm/mmap.c:2473
 do_vmi_munmap+0x26e/0x2c0 mm/mmap.c:2530
 __vm_munmap+0x133/0x3b0 mm/mmap.c:2805
 __do_sys_munmap mm/mmap.c:2830 [inline]
 __se_sys_munmap mm/mmap.c:2827 [inline]
 __x64_sys_munmap+0x62/0x80 mm/mmap.c:2827
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff888073ef2f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888073ef2f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888073ef3000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888073ef3080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888073ef3100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================