EXT4-fs error (device loop0): make_indexed_dir:2282: inode #2: block 255: comm syz-executor.0: bad entry in directory: rec_len is smaller than minimal - offset=0, inode=5120, rec_len=0, size=993 fake=0
EXT4-fs warning (device loop0): dx_probe:832: inode #2: comm syz-executor.0: Unrecognised inode hash code 49
EXT4-fs warning (device loop0): dx_probe:965: inode #2: comm syz-executor.0: Corrupt directory, running e2fsck is recommended
==================================================================
BUG: KASAN: use-after-free in __ext4_check_dir_entry+0x6fd/0x880 fs/ext4/dir.c:85
Read of size 2 at addr ffff88806bae2003 by task syz-executor.0/5561

CPU: 0 PID: 5561 Comm: syz-executor.0 Not tainted 6.9.0-syzkaller-12124-g6d69b6c12fce #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+0x241/0x360 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 __ext4_check_dir_entry+0x6fd/0x880 fs/ext4/dir.c:85
 ext4_readdir+0x130d/0x3500 fs/ext4/dir.c:258
 iterate_dir+0x65e/0x820 fs/readdir.c:110
 __do_sys_getdents64 fs/readdir.c:409 [inline]
 __se_sys_getdents64+0x20d/0x4f0 fs/readdir.c:394
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc5ff27dd69
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:00007fc60009b0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fc5ff3abf80 RCX: 00007fc5ff27dd69
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007fc5ff2ca49e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fc5ff3abf80 R15: 00007fffa5e99518
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1a2 pfn:0x6bae2
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001cb7388 ffffea0001cb27c8 0000000000000000
raw: 00000000000001a2 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 5575, tgid 5575 (sed), ts 90041729434, free_ts 90060005121
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468
 prep_new_page mm/page_alloc.c:1476 [inline]
 get_page_from_freelist+0x2e2d/0x2ee0 mm/page_alloc.c:3402
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4660
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 vma_alloc_folio_noprof+0xf3/0x1f0 mm/mempolicy.c:2304
 folio_prealloc+0x31/0x170
 do_cow_fault mm/memory.c:4950 [inline]
 do_fault mm/memory.c:5058 [inline]
 do_pte_missing mm/memory.c:3903 [inline]
 handle_pte_fault+0xd8b/0x7130 mm/memory.c:5380
 __handle_mm_fault mm/memory.c:5523 [inline]
 handle_mm_fault+0xfb0/0x19d0 mm/memory.c:5688
 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
page last free pid 5583 tgid 5583 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1088 [inline]
 free_unref_folios+0xf12/0x19c0 mm/page_alloc.c:2614
 folios_put_refs+0x93a/0xa60 mm/swap.c:1024
 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:329
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373
 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465
 exit_mmap+0x44f/0xc80 mm/mmap.c:3325
 __mmput+0x115/0x3c0 kernel/fork.c:1346
 exit_mm+0x220/0x310 kernel/exit.c:565
 do_exit+0x9aa/0x27e0 kernel/exit.c:861
 do_group_exit+0x207/0x2c0 kernel/exit.c:1023
 __do_sys_exit_group kernel/exit.c:1034 [inline]
 __se_sys_exit_group kernel/exit.c:1032 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1032
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88806bae1f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88806bae1f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88806bae2000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88806bae2080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88806bae2100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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