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+0x458/0xe34 fs/reiserfs/namei.c:165
Read of size 4 at addr ffff0000effd57c4 by task syz.0.16/5016

CPU: 0 PID: 5016 Comm: syz.0.16 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call trace:
 dump_backtrace+0x0/0x458 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x78/0x30c mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xec/0x158 mm/kasan/report.c:451
 __asan_report_load_n_noabort+0x40/0x4c mm/kasan/report_generic.c:319
 bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
 search_by_entry_key+0x458/0xe34 fs/reiserfs/namei.c:165
 reiserfs_find_entry+0xbf8/0x139c fs/reiserfs/namei.c:322
 reiserfs_lookup+0x190/0x3e0 fs/reiserfs/namei.c:368
 __lookup_slow+0x25c/0x39c fs/namei.c:1671
 lookup_one_len+0x17c/0x298 fs/namei.c:2726
 reiserfs_lookup_privroot+0x8c/0x204 fs/reiserfs/xattr.c:980
 reiserfs_fill_super+0x1800/0x1bfc fs/reiserfs/super.c:2178
 mount_bdev+0x264/0x358 fs/super.c:1400
 get_super_block+0x44/0x58 fs/reiserfs/super.c:2608
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:611
 vfs_get_tree+0x90/0x274 fs/super.c:1530
 do_new_mount+0x228/0x810 fs/namespace.c:3034
 path_mount+0x5bc/0x1008 fs/namespace.c:3364
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount fs/namespace.c:3562 [inline]
 __arm64_sys_mount+0x514/0x5f0 fs/namespace.c:3562
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1d0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

The buggy address belongs to the page:
page:00000000e0ccb213 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12ffd5
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003bff548 fffffc0003bff548 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000effd5680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000effd5700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000effd5780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff0000effd5800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000effd5880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.