==================================================================
BUG: KASAN: use-after-free in __list_add_valid_or_report+0x112/0x130 lib/list_debug.c:32
Read of size 8 at addr ffff888116a10250 by task kworker/1:5/9855

CPU: 1 UID: 0 PID: 9855 Comm: kworker/1:5 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events request_module_async
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 __list_add_valid_or_report+0x112/0x130 lib/list_debug.c:32
 __list_add_valid include/linux/list.h:96 [inline]
 __list_add include/linux/list.h:158 [inline]
 list_add_tail include/linux/list.h:191 [inline]
 em28xx_init_extension+0x48/0x200 drivers/media/usb/em28xx/em28xx-core.c:1114
 request_module_async+0x61/0x80 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888116a10140 pfn:0x116a10
flags: 0x200000000000000(node=0|zone=2)
page_type: f0(buddy)
raw: 0200000000000000 ffffea000414cd88 ffffea0004c8b188 0000000000000000
raw: ffff888116a10140 0000000000000001 00000000f0000000 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 0x440dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO|__GFP_COMP), pid 16027, tgid 16027 (syz-executor), ts 2279088375536, free_ts 2281241095842
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0xf10/0x39f0 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x273/0x2860 mm/page_alloc.c:5250
 alloc_pages_mpol+0xe8/0x410 mm/mempolicy.c:2484
 alloc_frozen_pages_noprof mm/mempolicy.c:2555 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2575
 pagetable_alloc_noprof include/linux/mm.h:3404 [inline]
 __pte_alloc_one_noprof include/asm-generic/pgalloc.h:76 [inline]
 pte_alloc_one+0x1c/0x3d0 arch/x86/mm/pgtable.c:18
 __pte_alloc+0x6d/0x3e0 mm/memory.c:466
 copy_pte_range mm/memory.c:1250 [inline]
 copy_pmd_range mm/memory.c:1405 [inline]
 copy_pud_range mm/memory.c:1442 [inline]
 copy_p4d_range mm/memory.c:1466 [inline]
 copy_page_range+0x1698/0x2760 mm/memory.c:1552
 dup_mmap+0xcb9/0x1f30 mm/mmap.c:1841
 dup_mm kernel/fork.c:1531 [inline]
 copy_mm kernel/fork.c:1583 [inline]
 copy_process+0x424b/0x7820 kernel/fork.c:2223
 kernel_clone+0xfc/0x9a0 kernel/fork.c:2653
 __do_sys_clone+0xd9/0x120 kernel/fork.c:2794
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0x7b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 14 tgid 14 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0x7b1/0xfb0 mm/page_alloc.c:2978
 __pagetable_free include/linux/mm.h:3414 [inline]
 pagetable_free include/linux/mm.h:3438 [inline]
 pagetable_dtor_free include/linux/mm.h:3537 [inline]
 __tlb_remove_table include/asm-generic/tlb.h:221 [inline]
 __tlb_remove_table_free mm/mmu_gather.c:228 [inline]
 tlb_remove_table_rcu+0x2cf/0x380 mm/mmu_gather.c:291
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869
 handle_softirqs+0x1de/0x9d0 kernel/softirq.c:622
 run_ksoftirqd kernel/softirq.c:1063 [inline]
 run_ksoftirqd+0x38/0x60 kernel/softirq.c:1055
 smpboot_thread_fn+0x3d3/0xaa0 kernel/smpboot.c:160
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888116a10100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888116a10180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888116a10200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                 ^
 ffff888116a10280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888116a10300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================