================================================================== BUG: KASAN: use-after-free in crc_itu_t+0x1f5/0x280 lib/crc-itu-t.c:60 Read of size 1 at addr ffff8880746d8000 by task syz-executor.0/4436 CPU: 0 PID: 4436 Comm: syz-executor.0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: 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+0x1f5/0x280 lib/crc-itu-t.c:60 udf_finalize_lvid fs/udf/super.c:2057 [inline] udf_sync_fs+0x194/0x350 fs/udf/super.c:2413 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 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: 0033:0x7fc4c1c85c87 Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 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 b0 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007fffd37fd7e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fc4c1cdfc5a RCX: 00007fc4c1c85c87 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007fffd37fd8a0 RBP: 00007fffd37fd8a0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffd37fe960 R13: 00007fc4c1cdfc5a R14: 0000000000012aa5 R15: 0000000000000006 Allocated by task 4475: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 anon_vma_chain_alloc mm/rmap.c:138 [inline] anon_vma_clone+0xbd/0x4f0 mm/rmap.c:284 anon_vma_fork+0x7e/0x500 mm/rmap.c:347 dup_mmap kernel/fork.c:574 [inline] dup_mm kernel/fork.c:1466 [inline] copy_mm+0x9e3/0x1380 kernel/fork.c:1518 copy_process+0x17c6/0x3e00 kernel/fork.c:2290 kernel_clone+0x219/0x930 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2796 [inline] __se_sys_clone kernel/fork.c:2780 [inline] __x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780 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 Freed by task 4476: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 anon_vma_chain_free mm/rmap.c:143 [inline] unlink_anon_vmas+0x2c8/0x660 mm/rmap.c:417 free_pgtables+0x177/0x2a0 mm/memory.c:426 exit_mmap+0x39e/0x5f0 mm/mmap.c:3217 __mmput+0x115/0x3b0 kernel/fork.c:1127 exec_mmap+0x4d1/0x5c0 fs/exec.c:1035 begin_new_exec+0x7e8/0x1160 fs/exec.c:1293 load_elf_binary+0x98e/0x2890 fs/binfmt_elf.c:1001 search_binary_handler fs/exec.c:1742 [inline] exec_binprm fs/exec.c:1783 [inline] bprm_execve+0xa92/0x17d0 fs/exec.c:1852 do_execveat_common+0x51e/0x6d0 fs/exec.c:1957 do_execve fs/exec.c:2027 [inline] __do_sys_execve fs/exec.c:2103 [inline] __se_sys_execve fs/exec.c:2098 [inline] __x64_sys_execve+0x8e/0xa0 fs/exec.c:2098 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 The buggy address belongs to the object at ffff8880746d8000 which belongs to the cache anon_vma_chain of size 80 The buggy address is located 0 bytes inside of 80-byte region [ffff8880746d8000, ffff8880746d8050) The buggy address belongs to the page: page:ffffea0001d1b600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x746d8 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0001d1b7c0 0000000800000008 ffff888140007140 raw: 0000000000000000 0000000000240024 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12800(GFP_NOWAIT|__GFP_NOWARN|__GFP_NORETRY), pid 4066, ts 45009630611, free_ts 45004162686 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:5487 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x195/0x290 mm/slub.c:3238 anon_vma_chain_alloc mm/rmap.c:138 [inline] anon_vma_clone+0xbd/0x4f0 mm/rmap.c:284 anon_vma_fork+0x7e/0x500 mm/rmap.c:347 dup_mmap kernel/fork.c:574 [inline] dup_mm kernel/fork.c:1466 [inline] copy_mm+0x9e3/0x1380 kernel/fork.c:1518 copy_process+0x17c6/0x3e00 kernel/fork.c:2290 kernel_clone+0x219/0x930 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2796 [inline] __se_sys_clone kernel/fork.c:2780 [inline] __x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780 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_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:3218 __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: ffff8880746d7f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880746d7f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880746d8000: fa fb fb fb fb fb fb fb fb fb fc fc fc fc fa fb ^ ffff8880746d8080: fb fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb ffff8880746d8100: fb fb fb fb fb fb fc fc fc fc fa fb fb fb fb fb ==================================================================