Description
In the Linux kernel, the following vulnerability has been resolved:
usb: dwc2: gadget: Fix spin_lock/unlock mismatch in dwc2_hsotg_udc_stop()
dwc2_gadget_exit_clock_gating() internally calls call_gadget() macro,
which expects hsotg->lock to be held since it does spin_unlock/spin_lock
around the gadget driver callback invocation.
However, dwc2_hsotg_udc_stop() calls dwc2_gadget_exit_clock_gating()
without holding the lock. This leads to:
- spin_unlock on a lock that is not held (undefined behavior)
- The lock remaining held after dwc2_gadget_exit_clock_gating() returns,
causing a deadlock when spin_lock_irqsave() is called later in the
same function.
Fix this by acquiring hsotg->lock before calling
dwc2_gadget_exit_clock_gating() and releasing it afterwards, which
satisfies the locking requirement of the call_gadget() macro.