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BUG: KASAN: use-after-free in __list_add_valid_or_report+0x112/0x130 lib/list_debug.c:32
Read of size 8 at addr ffff888127cc4250 by task kworker/1:6/11928

CPU: 1 UID: 0 PID: 11928 Comm: kworker/1:6 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1d0 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:1245
 request_module_async+0x61/0x80 drivers/media/usb/em28xx/em28xx-cards.c:3660
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
 process_scheduled_works kernel/workqueue.c:3397 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x69a/0xc80 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:0xffff888127cc4000 pfn:0x127cc4
flags: 0x200000000000000(node=0|zone=2)
raw: 0200000000000000 dead000000000100 dead000000000122 0000000000000000
raw: ffff888127cc4000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x40cc0(GFP_KERNEL|__GFP_COMP), pid 28, tgid 28 (kworker/1:1), ts 1630092133719, free_ts 1630513166089
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1853
 prep_new_page mm/page_alloc.c:1861 [inline]
 get_page_from_freelist+0x20a5/0x3850 mm/page_alloc.c:3941
 __alloc_frozen_pages_noprof+0x273/0x28a0 mm/page_alloc.c:5221
 alloc_pages_mpol+0xe8/0x410 mm/mempolicy.c:2490
 ___kmalloc_large_node+0xe5/0x120 mm/slub.c:5237
 __kmalloc_large_node_noprof+0x1c/0x70 mm/slub.c:5268
 __do_kmalloc_node mm/slub.c:5284 [inline]
 __kmalloc_node_track_caller_noprof+0x584/0x800 mm/slub.c:5408
 kmemdup_noprof+0x29/0x60 mm/util.c:138
 kmemdup_noprof include/linux/fortify-string.h:763 [inline]
 em28xx_duplicate_dev drivers/media/usb/em28xx/em28xx-cards.c:3940 [inline]
 em28xx_usb_probe.cold+0x12bc/0x25f6 drivers/media/usb/em28xx/em28xx-cards.c:4308
 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:631 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:709
 __driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
page last free pid 28 tgid 28 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0x6d8/0xf60 mm/page_alloc.c:2938
 kref_put.constprop.0.isra.0+0x4d/0x6d include/linux/kref.h:65
 em28xx_usb_disconnect.cold+0x1b4/0x253 drivers/media/usb/em28xx/em28xx-cards.c:4430
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:621 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:613
 __device_release_driver drivers/base/dd.c:1352 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1375
 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:657
 device_del+0x376/0x9b0 drivers/base/core.c:3895
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
 hub_port_connect drivers/usb/core/hub.c:5407 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
 process_scheduled_works kernel/workqueue.c:3397 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x69a/0xc80 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:
 ffff888127cc4100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888127cc4180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888127cc4200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                 ^
 ffff888127cc4280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888127cc4300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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