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UDF-fs: error (device loop0): udf_verify_fi: directory (ino 1376) has entry at pos 0 with incorrect tag 0
UDF-fs: error (device loop0): udf_verify_fi: directory (ino 1376) has entry at pos 0 with incorrect tag 0
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BUG: KASAN: use-after-free in crc_itu_t+0x1ad/0x280 lib/crc-itu-t.c:60
Read of size 1 at addr ffff88806a085000 by task syz-executor/4284

CPU: 1 PID: 4284 Comm: syz-executor Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 crc_itu_t+0x1ad/0x280 lib/crc-itu-t.c:60
 udf_finalize_lvid fs/udf/super.c:2048 [inline]
 udf_sync_fs+0x194/0x350 fs/udf/super.c:2404
 sync_filesystem+0xe6/0x220 fs/sync.c:56
 generic_shutdown_super+0x6b/0x300 fs/super.c:448
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1139
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x61e/0x20a0 kernel/exit.c:883
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f42eff79929
Code: Unable to access opcode bytes at RIP 0x7f42eff798ff.
RSP: 002b:00007fff35993398 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f42efffb997 RCX: 00007f42eff79929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000010 R08: 00007fff35991136 R09: 00007fff35994650
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff35994650
R13: 00007f42efffb925 R14: 00005555650754a8 R15: 00007fff35995720
 </TASK>

The buggy address belongs to the page:
page:ffffea0001a82140 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x6a085
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001a3abc8 ffffea0001a4bc08 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 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 4284, ts 84100289477, free_ts 84612708019
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5474
 alloc_pages_vma+0x393/0x7c0 mm/mempolicy.c:2146
 wp_page_copy+0x235/0x1fd0 mm/memory.c:3056
 handle_pte_fault mm/memory.c:4668 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x1eca/0x43c0 mm/memory.c:4883
 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357
 handle_page_fault arch/x86/mm/fault.c:1445 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page_list+0x122/0x7e0 mm/page_alloc.c:3433
 release_pages+0x184b/0x1bb0 mm/swap.c:963
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x164/0x2e0 mm/mmu_gather.c:338
 exit_mmap+0x3a6/0x5f0 mm/mmap.c:3214
 __mmput+0x115/0x3b0 kernel/fork.c:1127
 exit_mm+0x567/0x6c0 kernel/exit.c:550
 do_exit+0x5a1/0x20a0 kernel/exit.c:870
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Memory state around the buggy address:
 ffff88806a084f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88806a084f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88806a085000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88806a085080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806a085100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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