In the Linux kernel, the following vulnerability has been resolved:
usb: acpi: Prevent null pointer dereference in usbacpiaddusb4devlink()
As demonstrated by the fix for updateportdevicestate, commit 12783c0b9e2c ("usb: core: Prevent null pointer dereference in updateportdevicestate"), usbhubtostructhub() can return NULL in certain scenarios, such as during hub driver unbind or teardown race conditions, even if the underlying usb_device structure exists.
Plus, all other places that call usbhubtostructhub() in the same file do check for NULL return values.
If usbhubtostructhub() returns NULL, the subsequent access to hub->ports[udev->portnum - 1] will cause a null pointer dereference.