The Google Project Zero employee Jann Horn sees dangers from device-specific kernel adjustments in Android and demands a rethink from the manufacturers.Reading time:1 min.Save in pocketreadPrint viewread comments32posts
The German security researcher Jann Horn, who currently works for Google’s Project Zero and was involved in the discovery of the processor gaps Specter and Meltdown, criticized Android device manufacturers in a blog post . According to his statement, their device-specific changes to the kernel cause security gaps that could be avoided if the manufacturers would instead either pack these adaptations into userspace drivers or incorporate them into the upstream branch.
According to the current status, the manufacturers of Android smartphones and tablets can make specific adjustments to the Android kernel from Google for the respective device. However, this code is often a source of vulnerabilities and malware vulnerabilities. To reduce this risk, Google is now installing additional security functions. Android meanwhile limits access to these manufacturer-specific device drivers to selected software processes. Modern Android smartphones also access the hardware through specially designated so-called helper processes, which together form the hardware abstraction layer (HAL).
Standard interfaces provide more security
In order to further increase security, Jann Horn suggests that manufacturers will no longer make such accesses using their own drivers in future, but will instead use more secure interfaces. Examples include the user space driver framework VFIO (Virtual Function I / O), which was introduced in 2012 with Linux 3.6 , and access via / dev / bus / usb / for USB devices. As a side effect, this would also make it easier to install kernel updates on the devices, because long-lasting user space interfaces are used and fewer kernel APIs, which change from time to time.