usb 5-1: USB disconnect, device number 5
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BUG: KASAN: use-after-free in __media_entity_remove_links+0x134/0x160 drivers/media/mc/mc-entity.c:779
Read of size 8 at addr ffff8881cf96b920 by task kworker/0:3/4573

CPU: 0 PID: 4573 Comm: kworker/0:3 Not tainted 5.6.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xef/0x16e lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x314 mm/kasan/report.c:374
 __kasan_report.cold+0x37/0x77 mm/kasan/report.c:506
 kasan_report+0xe/0x20 mm/kasan/common.c:641
 __media_entity_remove_links+0x134/0x160 drivers/media/mc/mc-entity.c:779
 __media_device_unregister_entity+0x187/0x300 drivers/media/mc/mc-device.c:596
 media_device_unregister_entity+0x49/0x70 drivers/media/mc/mc-device.c:688
 v4l2_device_unregister_subdev+0x257/0x380 drivers/media/v4l2-core/v4l2-device.c:283
 v4l2_device_unregister drivers/media/v4l2-core/v4l2-device.c:100 [inline]
 v4l2_device_unregister+0x139/0x220 drivers/media/v4l2-core/v4l2-device.c:88
 uvc_unregister_video+0x11a/0x210 drivers/media/usb/uvc/uvc_driver.c:1957
 uvc_disconnect+0xbc/0x160 drivers/media/usb/uvc/uvc_driver.c:2270
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436
 __device_release_driver drivers/base/dd.c:1137 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1168
 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533
 device_del+0x481/0xd30 drivers/base/core.c:2677
 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237
 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2211
 hub_port_connect drivers/usb/core/hub.c:5046 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5335 [inline]
 port_event drivers/usb/core/hub.c:5481 [inline]
 hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5563
 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264
 worker_thread+0x96/0xe20 kernel/workqueue.c:2410
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 4574:
 save_stack+0x1b/0x80 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:515 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:488
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 media_add_link+0x47/0x180 drivers/media/mc/mc-entity.c:592
 media_create_pad_link+0x1fb/0x530 drivers/media/mc/mc-entity.c:684
 uvc_mc_create_links drivers/media/usb/uvc/uvc_entity.c:50 [inline]
 uvc_mc_register_entities+0x468/0x77a drivers/media/usb/uvc/uvc_entity.c:114
 uvc_register_chains drivers/media/usb/uvc/uvc_driver.c:2103 [inline]
 uvc_probe.cold+0x205c/0x2a51 drivers/media/usb/uvc/uvc_driver.c:2229
 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374
 really_probe+0x290/0xac0 drivers/base/dd.c:551
 driver_probe_device+0x223/0x350 drivers/base/dd.c:724
 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
 __device_attach+0x217/0x390 drivers/base/dd.c:897
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0x1459/0x1bf0 drivers/base/core.c:2500
 usb_set_configuration+0xe47/0x17d0 drivers/usb/core/message.c:2023
 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241
 usb_probe_device+0xd9/0x230 drivers/usb/core/driver.c:272
 really_probe+0x290/0xac0 drivers/base/dd.c:551
 driver_probe_device+0x223/0x350 drivers/base/dd.c:724
 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
 __device_attach+0x217/0x390 drivers/base/dd.c:897
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0x1459/0x1bf0 drivers/base/core.c:2500
 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2548
 hub_port_connect drivers/usb/core/hub.c:5195 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5335 [inline]
 port_event drivers/usb/core/hub.c:5481 [inline]
 hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5563
 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264
 process_scheduled_works kernel/workqueue.c:2326 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Freed by task 4573:
 save_stack+0x1b/0x80 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:337 [inline]
 __kasan_slab_free+0x117/0x160 mm/kasan/common.c:476
 slab_free_hook mm/slub.c:1444 [inline]
 slab_free_freelist_hook mm/slub.c:1477 [inline]
 slab_free mm/slub.c:3024 [inline]
 kfree+0xd5/0x300 mm/slub.c:3976
 __media_entity_remove_link+0x28c/0x660 drivers/media/mc/mc-entity.c:622
 __media_entity_remove_links+0x86/0x160 drivers/media/mc/mc-entity.c:780
 __media_device_unregister_entity+0x187/0x300 drivers/media/mc/mc-device.c:596
 media_device_unregister_entity+0x49/0x70 drivers/media/mc/mc-device.c:688
 v4l2_device_unregister_subdev+0x257/0x380 drivers/media/v4l2-core/v4l2-device.c:283
 v4l2_device_unregister drivers/media/v4l2-core/v4l2-device.c:100 [inline]
 v4l2_device_unregister+0x139/0x220 drivers/media/v4l2-core/v4l2-device.c:88
 uvc_unregister_video+0x11a/0x210 drivers/media/usb/uvc/uvc_driver.c:1957
 uvc_disconnect+0xbc/0x160 drivers/media/usb/uvc/uvc_driver.c:2270
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436
 __device_release_driver drivers/base/dd.c:1137 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1168
 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533
 device_del+0x481/0xd30 drivers/base/core.c:2677
 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237
 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2211
 hub_port_connect drivers/usb/core/hub.c:5046 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5335 [inline]
 port_event drivers/usb/core/hub.c:5481 [inline]
 hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5563
 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264
 worker_thread+0x96/0xe20 kernel/workqueue.c:2410
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff8881cf96b900
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 32 bytes inside of
 96-byte region [ffff8881cf96b900, ffff8881cf96b960)
The buggy address belongs to the page:
page:ffffea00073e5ac0 refcount:1 mapcount:0 mapping:ffff8881da002f00 index:0x0
flags: 0x200000000000200(slab)
raw: 0200000000000200 0000000000000000 0000000100000001 ffff8881da002f00
raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881cf96b800: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff8881cf96b880: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff8881cf96b900: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                               ^
 ffff8881cf96b980: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff8881cf96ba00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
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