em28xx 8-1:0.0: Disconnecting em28xx #3
em28xx 8-1:0.0: Disconnecting em28xx
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BUG: KASAN: out-of-bounds in __list_del_entry_valid_or_report+0x1e1/0x200 lib/list_debug.c:65
Read of size 8 at addr ffff888055474258 by task kworker/1:0/29

CPU: 1 UID: 0 PID: 29 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 __list_del_entry_valid_or_report+0x1e1/0x200 lib/list_debug.c:65
 __list_del_entry_valid include/linux/list.h:124 [inline]
 __list_del_entry include/linux/list.h:215 [inline]
 list_del include/linux/list.h:229 [inline]
 em28xx_close_extension+0x10b/0x2b0 drivers/media/usb/em28xx/em28xx-core.c:1137
 em28xx_usb_disconnect+0x19d/0x610 drivers/media/usb/em28xx/em28xx-cards.c:4197
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:571 [inline]
 device_remove+0x122/0x170 drivers/base/dd.c:563
 __device_release_driver drivers/base/dd.c:1274 [inline]
 device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1297
 bus_remove_device+0x22f/0x420 drivers/base/bus.c:579
 device_del+0x396/0x9f0 drivers/base/core.c:3878
 usb_disable_device+0x355/0x7d0 drivers/usb/core/message.c:1418
 usb_disconnect+0x2e1/0x9c0 drivers/usb/core/hub.c:2344
 hub_port_connect drivers/usb/core/hub.c:5406 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x1c81/0x4fe0 drivers/usb/core/hub.c:5952
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888055474340 pfn:0x55474
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff888055474340 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x92c00(GFP_NOIO|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC), pid 66, tgid 66 (kworker/2:2), ts 103222128411, free_ts 103201305443
 create_dummy_stack mm/page_owner.c:94 [inline]
 register_dummy_stack+0x89/0xd0 mm/page_owner.c:100
 init_page_owner+0x48/0x7e0 mm/page_owner.c:118
 invoke_init_callbacks mm/page_ext.c:148 [inline]
 page_ext_init+0x703/0xb00 mm/page_ext.c:486
 mm_core_init+0x13c/0x220 mm/mm_init.c:2789
page last free pid 66 tgid 66 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895
 em28xx_free_device drivers/media/usb/em28xx/em28xx-cards.c:3566 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_usb_disconnect+0x4e0/0x610 drivers/media/usb/em28xx/em28xx-cards.c:4204
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:571 [inline]
 device_remove+0x122/0x170 drivers/base/dd.c:563
 __device_release_driver drivers/base/dd.c:1274 [inline]
 device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1297
 bus_remove_device+0x22f/0x420 drivers/base/bus.c:579
 device_del+0x396/0x9f0 drivers/base/core.c:3878
 usb_disable_device+0x355/0x7d0 drivers/usb/core/message.c:1418
 usb_disconnect+0x2e1/0x9c0 drivers/usb/core/hub.c:2344
 hub_port_connect drivers/usb/core/hub.c:5406 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x1c81/0x4fe0 drivers/usb/core/hub.c:5952
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888055474100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888055474180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888055474200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                       ^
 ffff888055474280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888055474300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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