EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
EXT4-fs (loop0): 1 truncate cleaned up
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
==================================================================
BUG: KASAN: use-after-free in ext4_search_dir+0xf2/0x1b0 fs/ext4/namei.c:1543
Read of size 1 at addr ffff888076eba3ed by task syz-executor.0/5496

CPU: 0 PID: 5496 Comm: syz-executor.0 Not tainted 6.7.0-rc4-syzkaller-00009-gbee0e7762ad2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:475
 kasan_report+0x142/0x170 mm/kasan/report.c:588
 ext4_search_dir+0xf2/0x1b0 fs/ext4/namei.c:1543
 ext4_find_inline_entry+0x4ba/0x5e0 fs/ext4/inline.c:1694
 __ext4_find_entry+0x2b4/0x1b30 fs/ext4/namei.c:1616
 ext4_lookup_entry fs/ext4/namei.c:1771 [inline]
 ext4_lookup+0x17a/0x750 fs/ext4/namei.c:1839
 lookup_open fs/namei.c:3455 [inline]
 open_last_lookups fs/namei.c:3546 [inline]
 path_openat+0x1010/0x3290 fs/namei.c:3776
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7ffb8867c959
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:00007ffb8947b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ffb8879bf80 RCX: 00007ffb8867c959
RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000100
RBP: 00007ffb886d8c88 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007ffb8879bf80 R15: 00007ffe408b5b78
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001dbae80 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x76eba
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea0001c488c8 ffffea0001cac948 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 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 5500, tgid 5500 (dhcpcd-run-hook), ts 81532015497, free_ts 81575925016
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1544 [inline]
 get_page_from_freelist+0x33ea/0x3570 mm/page_alloc.c:3312
 __alloc_pages+0x255/0x680 mm/page_alloc.c:4568
 alloc_pages_mpol+0x3de/0x640 mm/mempolicy.c:2133
 vma_alloc_folio+0xf3/0x3f0 mm/mempolicy.c:2172
 wp_page_copy mm/memory.c:3119 [inline]
 do_wp_page+0x125e/0x4d40 mm/memory.c:3510
 handle_pte_fault mm/memory.c:5054 [inline]
 __handle_mm_fault mm/memory.c:5179 [inline]
 handle_mm_fault+0x1b1c/0x6680 mm/memory.c:5344
 do_user_addr_fault arch/x86/mm/fault.c:1364 [inline]
 handle_page_fault arch/x86/mm/fault.c:1505 [inline]
 exc_page_fault+0x456/0x870 arch/x86/mm/fault.c:1561
 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:1137 [inline]
 free_unref_page_prepare+0x931/0xa60 mm/page_alloc.c:2347
 free_unref_page_list+0x5a0/0x840 mm/page_alloc.c:2533
 release_pages+0x2117/0x2400 mm/swap.c:1042
 tlb_batch_pages_flush mm/mmu_gather.c:98 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:293 [inline]
 tlb_flush_mmu+0x34c/0x4e0 mm/mmu_gather.c:300
 tlb_finish_mmu+0xd4/0x1f0 mm/mmu_gather.c:392
 exit_mmap+0x4d3/0xc60 mm/mmap.c:3321
 __mmput+0x115/0x3c0 kernel/fork.c:1349
 exit_mm+0x21f/0x300 kernel/exit.c:567
 do_exit+0x9b7/0x2750 kernel/exit.c:858
 do_group_exit+0x206/0x2c0 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1030
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Memory state around the buggy address:
 ffff888076eba280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888076eba300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888076eba380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                          ^
 ffff888076eba400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888076eba480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================