EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
EXT4-fs (loop0): 1 truncate cleaned up
EXT4-fs (loop0): mounted filesystem without journal. Quota mode: none.
==================================================================
BUG: KASAN: use-after-free in ext4_search_dir+0xf7/0x1b0 fs/ext4/namei.c:1543
Read of size 1 at addr ffff888126027d23 by task syz-executor.0/369

CPU: 0 PID: 369 Comm: syz-executor.0 Not tainted 6.1.93-syzkaller-1151384-g3bb5a64ae9b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0x158/0x4e0 mm/kasan/report.c:427
 kasan_report+0x13c/0x170 mm/kasan/report.c:531
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:348
 ext4_search_dir+0xf7/0x1b0 fs/ext4/namei.c:1543
 ext4_find_inline_entry+0x4b6/0x5e0 fs/ext4/inline.c:1722
 __ext4_find_entry+0x2b0/0x1af0 fs/ext4/namei.c:1616
 ext4_lookup_entry fs/ext4/namei.c:1771 [inline]
 ext4_lookup+0x176/0x740 fs/ext4/namei.c:1839
 lookup_open fs/namei.c:3461 [inline]
 open_last_lookups fs/namei.c:3551 [inline]
 path_openat+0x10fd/0x2d60 fs/namei.c:3781
 do_filp_open+0x230/0x480 fs/namei.c:3811
 do_sys_openat2+0x151/0x890 fs/open.c:1341
 do_sys_open fs/open.c:1357 [inline]
 __do_sys_creat fs/open.c:1433 [inline]
 __se_sys_creat fs/open.c:1427 [inline]
 __x64_sys_creat+0x11f/0x160 fs/open.c:1427
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:86
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd71a87cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fd71b5730c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fd71a99bf80 RCX: 00007fd71a87cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000e00
RBP: 00007fd71a8c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd71a99bf80 R15: 00007ffc32818d68
 </TASK>

The buggy address belongs to the physical page:
page:ffffea00049809c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x126027
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 ffffea0004980a08 ffffea0004980988 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff888126027c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888126027c80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888126027d00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                               ^
 ffff888126027d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888126027e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
EXT4-fs error (device loop0): ext4_find_dest_de:2112: inode #12: block 7: comm syz-executor.0: bad entry in directory: rec_len % 4 != 0 - offset=0, inode=3089191003, rec_len=43069, size=56 fake=0