==================================================================
BUG: KASAN: use-after-free in ext4_search_dir+0xf7/0x1b0 fs/ext4/namei.c:1543
Read of size 1 at addr ffff8881231bf00a by task syz-executor.2/511

CPU: 1 PID: 511 Comm: syz-executor.2 Not tainted 6.1.78-syzkaller-00132-g92704e00b599 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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+0x13f/0x850 fs/open.c:1341
 do_sys_open fs/open.c:1357 [inline]
 __do_sys_openat fs/open.c:1373 [inline]
 __se_sys_openat fs/open.c:1368 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1368
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fcd1be7cee9
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:00007fcd1ccb50c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fcd1bfb4070 RCX: 00007fcd1be7cee9
RDX: 000000000000275a RSI: 0000000020000040 RDI: ffffffffffffff9c
RBP: 00007fcd1bec947f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fcd1bfb4070 R15: 00007ffd31ff6698
 </TASK>

The buggy address belongs to the physical page:
page:ffffea00048c6fc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x1231bf
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 ffffea000492f1c8 ffffea0004924108 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 0x8140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO|__GFP_CMA), pid 497, tgid 497 (syz-executor.2), ts 31245843511, free_ts 31290009800
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x213/0x220 mm/page_alloc.c:2590
 prep_new_page+0x1b/0x110 mm/page_alloc.c:2597
 get_page_from_freelist+0x27ea/0x2870 mm/page_alloc.c:4425
 __alloc_pages+0x3a1/0x780 mm/page_alloc.c:5712
 __folio_alloc+0x15/0x40 mm/page_alloc.c:5744
 __folio_alloc_node include/linux/gfp.h:245 [inline]
 folio_alloc include/linux/gfp.h:274 [inline]
 alloc_page_vma include/linux/gfp.h:283 [inline]
 do_anonymous_page mm/memory.c:4220 [inline]
 handle_pte_fault mm/memory.c:5099 [inline]
 __handle_mm_fault mm/memory.c:5243 [inline]
 handle_mm_fault+0x1fb0/0x2f40 mm/memory.c:5383
 do_user_addr_fault arch/x86/mm/fault.c:1414 [inline]
 handle_page_fault arch/x86/mm/fault.c:1506 [inline]
 exc_page_fault+0x24d/0x700 arch/x86/mm/fault.c:1562
 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:570
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1498 [inline]
 free_pcp_prepare mm/page_alloc.c:1572 [inline]
 free_unref_page_prepare+0x83d/0x850 mm/page_alloc.c:3498
 free_unref_page_list+0xf1/0x7b0 mm/page_alloc.c:3646
 release_pages+0xf7f/0xfe0 mm/swap.c:1063
 free_pages_and_swap_cache+0x8a/0xa0 mm/swap_state.c:314
 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:254 [inline]
 tlb_flush_mmu mm/mmu_gather.c:261 [inline]
 tlb_finish_mmu+0x1e0/0x3f0 mm/mmu_gather.c:361
 exit_mmap+0x421/0x940 mm/mmap.c:3348
 __mmput+0x95/0x310 kernel/fork.c:1298
 mmput+0x56/0x170 kernel/fork.c:1321
 exit_mm kernel/exit.c:566 [inline]
 do_exit+0xb29/0x2b80 kernel/exit.c:862
 do_group_exit+0x21a/0x2d0 kernel/exit.c:1025
 get_signal+0x169d/0x1820 kernel/signal.c:2880
 arch_do_signal_or_restart+0xb0/0x16f0 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x74/0xa0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87

Memory state around the buggy address:
 ffff8881231bef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881231bef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881231bf000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                      ^
 ffff8881231bf080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881231bf100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
EXT4-fs error (device loop2): ext4_find_dest_de:2112: inode #12: block 7: comm syz-executor.2: bad entry in directory: rec_len is smaller than minimal - offset=0, inode=0, rec_len=0, size=68 fake=0