kernel: KVM: cmpxchg_gpte can write to pfns outside the userspace region

A flaw was found in KVM. When updating a guest's page table entry, vmpgoff was improperly used as the offset to get the page's pfn. As vaddr and vmpgoff are controllable by user-mode processes, this flaw allows unprivileged local users on the host to write outside the userspace region and...

Kernel: KVM: OOB memory access via mmio ring buffer

An out-of-bounds access issue was found in the way Linux kernel's KVM hypervisor implements the Coalesced MMIO write operation. It operates on an MMIO ring buffer 'struct kvmcoalescedmmio' object, wherein write indices 'ring-first' and 'ring-last' value could be supplied by a host user-space...