syzbot

usb 4-1: USB disconnect, device number 13
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BUG: KMSAN: uninit-value in usb_unbind_interface+0x3a2/0xdd0 drivers/usb/core/driver.c:423
CPU: 0 PID: 11864 Comm: kworker/0:4 Not tainted 5.3.0-rc7+ #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+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x13a/0x2b0 mm/kmsan/kmsan_report.c:108
 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:250
 adu_disconnect+0x302/0x360 drivers/usb/misc/adutux.c:774
 usb_unbind_interface+0x3a2/0xdd0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1120 [inline]
 device_release_driver_internal+0x911/0xd20 drivers/base/dd.c:1151
 device_release_driver+0x4b/0x60 drivers/base/dd.c:1174
 bus_remove_device+0x4bf/0x670 drivers/base/bus.c:556
 device_del+0xcd5/0x1d10 drivers/base/core.c:2339
 usb_disable_device+0x567/0x1150 drivers/usb/core/message.c:1241
 usb_disconnect+0x51e/0xd60 drivers/usb/core/hub.c:2199
 hub_port_connect drivers/usb/core/hub.c:4949 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x3fd0/0x72f0 drivers/usb/core/hub.c:5441
 process_one_work+0x1572/0x1ef0 kernel/workqueue.c:2269
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2415
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:150 [inline]
 kmsan_internal_poison_shadow+0x53/0x100 mm/kmsan/kmsan.c:134
 kmsan_slab_free+0x8d/0x100 mm/kmsan/kmsan_hooks.c:123
 slab_free_freelist_hook mm/slub.c:1472 [inline]
 slab_free mm/slub.c:3038 [inline]
 kfree+0x4c1/0x2db0 mm/slub.c:3980
 adu_delete drivers/usb/misc/adutux.c:151 [inline]
 adu_release+0x95f/0xa50 drivers/usb/misc/adutux.c:332
 __fput+0x4c9/0xba0 fs/file_table.c:280
 ____fput+0x37/0x40 fs/file_table.c:313
 task_work_run+0x22e/0x2a0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xf29/0x3aa0 kernel/exit.c:881
 do_group_exit+0x18a/0x320 kernel/exit.c:985
 __do_sys_exit_group+0x21/0x30 kernel/exit.c:996
 __se_sys_exit_group+0x14/0x20 kernel/exit.c:994
 __x64_sys_exit_group+0x1d/0x20 kernel/exit.c:994
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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