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BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0xbe8/0xce0 fs/ext4/extents.c:953
Read of size 4 at addr ffff888070dc24b8 by task syz-executor.0/5500

CPU: 0 PID: 5500 Comm: syz-executor.0 Not tainted 6.6.0-rc3-syzkaller-00038-g0e945134b680 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:475
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
 ext4_find_extent+0xbe8/0xce0 fs/ext4/extents.c:953
 ext4_ext_map_blocks+0x26b/0x5b10 fs/ext4/extents.c:4101
 ext4_map_blocks+0x619/0x1770 fs/ext4/inode.c:621
 _ext4_get_block+0x24d/0x5a0 fs/ext4/inode.c:763
 __block_write_begin_int+0x3c0/0x14d0 fs/buffer.c:2111
 block_page_mkwrite+0x3db/0x4c0 fs/buffer.c:2628
 ext4_page_mkwrite+0xcfd/0x1760 fs/ext4/inode.c:6150
 do_page_mkwrite+0x17a/0x380 mm/memory.c:2931
 wp_page_shared mm/memory.c:3291 [inline]
 do_wp_page+0xc66/0x34b0 mm/memory.c:3376
 handle_pte_fault mm/memory.c:4994 [inline]
 __handle_mm_fault+0x1d1b/0x3e10 mm/memory.c:5119
 handle_mm_fault+0x478/0xa00 mm/memory.c:5284
 do_user_addr_fault+0x3d1/0x1000 arch/x86/mm/fault.c:1413
 handle_page_fault arch/x86/mm/fault.c:1505 [inline]
 exc_page_fault+0x5c/0xd0 arch/x86/mm/fault.c:1561
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7f2da7e5d577
Code: 48 ff c7 48 01 fe 48 8d 54 11 80 0f 1f 84 00 00 00 00 00 c5 fe 6f 0e c5 fe 6f 56 20 c5 fe 6f 5e 40 c5 fe 6f 66 60 48 83 ee 80 <c5> fd 7f 0f c5 fd 7f 57 20 c5 fd 7f 5f 40 c5 fd 7f 67 60 48 83 ef
RSP: 002b:00007fffce816968 EFLAGS: 00010203
RAX: 0000000020003600 RBX: 00007fffce816a78 RCX: 0000000020003600
RDX: 00000000200036a9 RSI: 00007f2da7a207b0 RDI: 0000000020003620
RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f2da7f9bf8c
R10: 00007fffce816aa0 R11: 0000000000000246 R12: 00007f2da7a206f0
R13: fffffffffffffffe R14: 00007f2da7a00000 R15: 00007f2da7a206f8
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001c37080 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x70dc2
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea0001c3a648 ffffea0001c3ab48 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 5496, tgid 5496 (sed), ts 83913380169, free_ts 83919004793
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536
 prep_new_page mm/page_alloc.c:1543 [inline]
 get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170
 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426
 __folio_alloc+0x16/0x40 mm/page_alloc.c:4458
 vma_alloc_folio+0x156/0x890 mm/mempolicy.c:2259
 wp_page_copy mm/memory.c:3074 [inline]
 do_wp_page+0x5bc/0x34b0 mm/memory.c:3449
 handle_pte_fault mm/memory.c:4994 [inline]
 __handle_mm_fault+0x1d1b/0x3e10 mm/memory.c:5119
 handle_mm_fault+0x478/0xa00 mm/memory.c:5284
 do_user_addr_fault+0x30b/0x1000 arch/x86/mm/fault.c:1364
 handle_page_fault arch/x86/mm/fault.c:1505 [inline]
 exc_page_fault+0x5c/0xd0 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:1136 [inline]
 free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312
 free_unref_page_list+0xe6/0xb30 mm/page_alloc.c:2451
 release_pages+0x32a/0x14e0 mm/swap.c:1042
 tlb_batch_pages_flush+0x9a/0x190 mm/mmu_gather.c:98
 tlb_flush_mmu_free mm/mmu_gather.c:293 [inline]
 tlb_flush_mmu mm/mmu_gather.c:300 [inline]
 tlb_finish_mmu+0x14b/0x6f0 mm/mmu_gather.c:392
 exit_mmap+0x38b/0xa60 mm/mmap.c:3223
 __mmput+0x12a/0x4d0 kernel/fork.c:1349
 mmput+0x62/0x70 kernel/fork.c:1371
 exit_mm kernel/exit.c:567 [inline]
 do_exit+0x9ad/0x2a20 kernel/exit.c:861
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024
 __do_sys_exit_group kernel/exit.c:1035 [inline]
 __se_sys_exit_group kernel/exit.c:1033 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff888070dc2380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888070dc2400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888070dc2480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                        ^
 ffff888070dc2500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888070dc2580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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