In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-v2: Check for non-NULL vCPU in vgicv2parseattr() vgicv2parseattr() is responsible for finding the vCPU that matches the user-provided CPUID, which (of course) may not be valid. If the ID is invalid, kvmgetvcpubyid() returns NULL, which isn't handled gracefully. Similar to the GICv3 uaccess flow, check that kvmgetvcpubyid() actually returns something and fail the ioctl if not.