REISERFS (device loop1): journal params: device loop1, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop1): checking transaction log (loop1)
REISERFS (device loop1): Using r5 hash to sort names
REISERFS (device loop1): 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+0x80b/0x940 fs/reiserfs/namei.c:165
Read of size 4 at addr ffff88804b8343b4 by task syz-executor.1/6358

CPU: 1 PID: 6358 Comm: syz-executor.1 Not tainted 6.7.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:475
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
 search_by_entry_key+0x80b/0x940 fs/reiserfs/namei.c:165
 reiserfs_find_entry+0x1dc/0xe70 fs/reiserfs/namei.c:322
 reiserfs_lookup+0x1f5/0x690 fs/reiserfs/namei.c:368
 __lookup_slow+0x24d/0x450 fs/namei.c:1694
 lookup_one_len+0x17d/0x1b0 fs/namei.c:2746
 reiserfs_lookup_privroot+0x94/0x200 fs/reiserfs/xattr.c:977
 reiserfs_fill_super+0x20f9/0x3160 fs/reiserfs/super.c:2174
 mount_bdev+0x1f3/0x2e0 fs/super.c:1650
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8c/0x370 fs/super.c:1771
 do_new_mount fs/namespace.c:3337 [inline]
 path_mount+0x1492/0x1ed0 fs/namespace.c:3664
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount fs/namespace.c:3863 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f349a67e3ea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f349b3b2ee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f349b3b2f80 RCX: 00007f349a67e3ea
RDX: 0000000020000540 RSI: 0000000020000140 RDI: 00007f349b3b2f40
RBP: 0000000020000540 R08: 00007f349b3b2f80 R09: 0000000000010000
R10: 0000000000010000 R11: 0000000000000202 R12: 0000000020000140
R13: 00007f349b3b2f40 R14: 0000000000001126 R15: 00000000200017c0
 </TASK>

The buggy address belongs to the physical page:
page:ffffea00012e0d00 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x1 pfn:0x4b834
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffff7f(buddy)
raw: 00fff00000000000 ffffea00012f3b08 ffffea00012d3508 0000000000000000
raw: 0000000000000001 0000000000000002 00000000ffffff7f 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 0x152c4a(GFP_NOFS|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL|__GFP_MOVABLE), pid 5947, tgid 5943 (syz-executor.4), ts 223526160447, free_ts 225342130154
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1544 [inline]
 get_page_from_freelist+0xa25/0x36d0 mm/page_alloc.c:3312
 __alloc_pages+0x22e/0x2420 mm/page_alloc.c:4568
 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133
 folio_alloc+0x1e/0xe0 mm/mempolicy.c:2211
 filemap_alloc_folio+0x3bb/0x490 mm/filemap.c:974
 page_cache_ra_unbounded+0x1ac/0x5f0 mm/readahead.c:247
 do_page_cache_ra mm/readahead.c:299 [inline]
 page_cache_ra_order+0x72b/0xa80 mm/readahead.c:546
 ondemand_readahead+0x493/0x1130 mm/readahead.c:668
 page_cache_async_ra mm/readahead.c:717 [inline]
 page_cache_async_ra+0x123/0x150 mm/readahead.c:699
 filemap_readahead mm/filemap.c:2472 [inline]
 filemap_get_pages+0x35a/0x1830 mm/filemap.c:2513
 filemap_read+0x39b/0xcf0 mm/filemap.c:2593
 generic_file_read_iter+0x346/0x450 mm/filemap.c:2781
 ext4_file_read_iter+0x1dc/0x6c0 fs/ext4/file.c:147
 __kernel_read+0x301/0x870 fs/read_write.c:428
 integrity_kernel_read+0x7f/0xb0 security/integrity/iint.c:221
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1137 [inline]
 free_unref_page_prepare+0x4fa/0xaa0 mm/page_alloc.c:2347
 free_unref_page_list+0xe6/0xb40 mm/page_alloc.c:2533
 release_pages+0x32a/0x14f0 mm/swap.c:1042
 __folio_batch_release+0x77/0xe0 mm/swap.c:1062
 folio_batch_release include/linux/pagevec.h:83 [inline]
 truncate_inode_pages_range+0x33e/0xf00 mm/truncate.c:371
 ext4_evict_inode+0x2c7/0x1a40 fs/ext4/inode.c:193
 evict+0x2ed/0x6b0 fs/inode.c:666
 iput_final fs/inode.c:1777 [inline]
 iput.part.0+0x560/0x7b0 fs/inode.c:1803
 iput+0x5c/0x80 fs/inode.c:1793
 do_unlinkat+0x60f/0x740 fs/namei.c:4389
 __do_sys_unlink fs/namei.c:4430 [inline]
 __se_sys_unlink fs/namei.c:4428 [inline]
 __x64_sys_unlink+0xc8/0x110 fs/namei.c:4428
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Memory state around the buggy address:
 ffff88804b834280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804b834300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88804b834380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                     ^
 ffff88804b834400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804b834480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================