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BUG: KASAN: use-after-free in crc_itu_t+0x1fa/0x280 lib/crc-itu-t.c:60
Read of size 1 at addr ffff88801e77c000 by task syz-executor/4882

CPU: 1 PID: 4882 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 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+0x1fa/0x280 lib/crc-itu-t.c:60
 udf_finalize_lvid fs/udf/super.c:2057 [inline]
 udf_close_lvid+0x554/0x9a0 fs/udf/super.c:2125
 udf_put_super+0xc8/0x160 fs/udf/super.c:2395
 generic_shutdown_super+0x130/0x300 fs/super.c:475
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc7b84e2157
Code: a2 c7 05 3c 84 23 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffddb8aed28 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fc7b857533b RCX: 00007fc7b84e2157
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffddb8aede0
RBP: 00007ffddb8aede0 R08: 00007ffddb8afde0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffddb8afe70
R13: 00007fc7b857533b R14: 00000000000181fe R15: 00007ffddb8afeb0
 </TASK>

The buggy address belongs to the page:
page:ffffea000079df00 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x1e77c
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0000ad5fc8 ffffea00008c3c88 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 4809, ts 92433907369, free_ts 92823469605
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5487
 vm_area_alloc_pages mm/vmalloc.c:2876 [inline]
 __vmalloc_area_node mm/vmalloc.c:2932 [inline]
 __vmalloc_node_range+0x4b2/0x8b0 mm/vmalloc.c:3037
 vmalloc_user+0x70/0x80 mm/vmalloc.c:3173
 kcov_mmap+0x27/0x120 kernel/kcov.c:474
 call_mmap include/linux/fs.h:2178 [inline]
 mmap_file+0x5d/0xb0 mm/util.c:1092
 __mmap_region mm/mmap.c:1796 [inline]
 mmap_region+0xf88/0x1650 mm/mmap.c:2933
 do_mmap+0x819/0xe90 mm/mmap.c:1586
 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:551
 ksys_mmap_pgoff+0x54b/0x790 mm/mmap.c:1635
 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
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+0x8f/0x2a0 mm/page_alloc.c:3396
 __vunmap+0x8b9/0xa50 mm/vmalloc.c:2628
 kcov_put kernel/kcov.c:417 [inline]
 kcov_close+0x27/0x50 kernel/kcov.c:519
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x626/0x20c0 kernel/exit.c:883
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 get_signal+0x6ca/0x12c0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Memory state around the buggy address:
 ffff88801e77bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88801e77bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88801e77c000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88801e77c080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88801e77c100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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