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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.
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BUG: KASAN: use-after-free in ext4_search_dir+0xf2/0x1b0 fs/ext4/namei.c:1539
Read of size 1 at addr ffff8880738a73ed by task syz-executor901/4987

CPU: 1 PID: 4987 Comm: syz-executor901 Not tainted 6.4.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
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:351 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:462
 kasan_report+0x176/0x1b0 mm/kasan/report.c:572
 ext4_search_dir+0xf2/0x1b0 fs/ext4/namei.c:1539
 ext4_find_inline_entry+0x4ba/0x5e0 fs/ext4/inline.c:1719
 __ext4_find_entry+0x2b4/0x1b30 fs/ext4/namei.c:1612
 ext4_lookup_entry fs/ext4/namei.c:1767 [inline]
 ext4_lookup+0x17a/0x750 fs/ext4/namei.c:1835
 lookup_open fs/namei.c:3470 [inline]
 open_last_lookups fs/namei.c:3560 [inline]
 path_openat+0x11e9/0x3170 fs/namei.c:3788
 do_filp_open+0x234/0x490 fs/namei.c:3818
 do_sys_openat2+0x13f/0x500 fs/open.c:1356
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_open fs/open.c:1380 [inline]
 __se_sys_open fs/open.c:1376 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1376
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb2e8a7b2d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffef7d78a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fffef7d78e8 RCX: 00007fb2e8a7b2d9
RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000100
RBP: 0000000000000000 R08: 000000000001f210 R09: 0000000000000000
R10: 00007fb2d826d000 R11: 0000000000000246 R12: 00007fffef7d78e0
R13: 0000000000000000 R14: 431bde82d7b634db R15: 0000000000000000
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001ce29c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x738a7
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea0001ce2a08 ffffea0001ce2988 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 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 4987, tgid 4987 (syz-executor901), ts 71330456893, free_ts 71360711112
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1731
 prep_new_page mm/page_alloc.c:1738 [inline]
 get_page_from_freelist+0x321c/0x33a0 mm/page_alloc.c:3502
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4768
 __folio_alloc+0x13/0x30 mm/page_alloc.c:4800
 vma_alloc_folio+0x48a/0x9a0 mm/mempolicy.c:2240
 do_anonymous_page mm/memory.c:4085 [inline]
 do_pte_missing mm/memory.c:3645 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x2942/0x5860 mm/memory.c:5243
 do_user_addr_fault arch/x86/mm/fault.c:1349 [inline]
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x274/0x910 arch/x86/mm/fault.c:1590
 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:1302 [inline]
 free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2564
 free_unref_page_list+0x596/0x830 mm/page_alloc.c:2705
 release_pages+0x2193/0x2470 mm/swap.c:1042
 tlb_batch_pages_flush mm/mmu_gather.c:97 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:292 [inline]
 tlb_flush_mmu+0x100/0x210 mm/mmu_gather.c:299
 tlb_finish_mmu+0xd4/0x1f0 mm/mmu_gather.c:391
 unmap_region+0x258/0x2a0 mm/mmap.c:2222
 do_vmi_align_munmap+0x1123/0x1820 mm/mmap.c:2473
 do_vmi_munmap+0x24a/0x2b0 mm/mmap.c:2530
 __vm_munmap+0x226/0x470 mm/mmap.c:2805
 __do_sys_munmap mm/mmap.c:2830 [inline]
 __se_sys_munmap mm/mmap.c:2827 [inline]
 __x64_sys_munmap+0x69/0x80 mm/mmap.c:2827
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff8880738a7280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880738a7300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8880738a7380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                          ^
 ffff8880738a7400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880738a7480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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