While the IPA driver in Android for MSM, Firefox OS for MSM, and QRD Android before 2017-08-31 is processing IOCTL commands there is no mutex lock of allocated memory. If one thread sends an ioctl cmd IPA_IOC_QUERY_RT_TBL_INDEX while another sends an ioctl cmd IPA_IOC_DEL_RT_RULE, a use-after-free condition may occur.