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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 tea 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+0x45c/0xe88 fs/reiserfs/namei.c:165
Read of size 4 at addr ffff0000e0c62fc4 by task syz-executor275/4223

CPU: 0 PID: 4223 Comm: syz-executor275 Not tainted 6.1.75-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x174/0x4c0 mm/kasan/report.c:395
 kasan_report+0xd4/0x130 mm/kasan/report.c:495
 __asan_report_load_n_noabort+0x28/0x34 mm/kasan/report_generic.c:361
 bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
 search_by_entry_key+0x45c/0xe88 fs/reiserfs/namei.c:165
 reiserfs_find_entry+0x288/0x149c fs/reiserfs/namei.c:322
 reiserfs_lookup+0x184/0x3c4 fs/reiserfs/namei.c:368
 __lookup_slow+0x250/0x374 fs/namei.c:1690
 lookup_one_len+0x178/0x28c fs/namei.c:2742
 reiserfs_lookup_privroot+0x8c/0x204 fs/reiserfs/xattr.c:973
 reiserfs_fill_super+0x1bc0/0x2028 fs/reiserfs/super.c:2174
 mount_bdev+0x274/0x370 fs/super.c:1432
 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
 vfs_get_tree+0x90/0x274 fs/super.c:1562
 do_new_mount+0x278/0x8fc fs/namespace.c:3051
 path_mount+0x590/0xe5c fs/namespace.c:3381
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount fs/namespace.c:3579 [inline]
 __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3579
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the physical page:
page:00000000cbd9c801 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x120c62
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc00038318c8 fffffc0003831848 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000e0c62e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000e0c62f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000e0c62f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff0000e0c63000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000e0c63080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
REISERFS warning (device loop0): jdm-13090 reiserfs_new_inode: ACLs aren't enabled in the fs, but vfs thinks they are!
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.