Commit 0123be42 authored by Nadav Amit's avatar Nadav Amit Committed by Paolo Bonzini
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KVM: x86: Assertions to check no overrun in MSR lists 



Currently there is no check whether shared MSRs list overrun the allocated size
which can results in bugs. In addition there is no check that vmx->guest_msrs
has sufficient space to accommodate all the VMX msrs.  This patch adds the
assertions.

Signed-off-by: default avatarNadav Amit <namit@cs.technion.ac.il>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent d6e8c854

arch/x86/kvm/vmx.c

+2 −0
Original line number Diff line number Diff line
@@ -7608,6 +7608,8 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) 
		goto free_vcpu;



	vmx->guest_msrs = kmalloc(PAGE_SIZE, GFP_KERNEL);

	BUILD_BUG_ON(PAGE_SIZE / sizeof(struct shared_msr_entry) < NR_VMX_MSR);



	err = -ENOMEM;

	if (!vmx->guest_msrs) {

		goto uninit_vcpu;

arch/x86/kvm/x86.c

+1 −0
Original line number Diff line number Diff line
@@ -212,6 +212,7 @@ static void shared_msr_update(unsigned slot, u32 msr) 


void kvm_define_shared_msr(unsigned slot, u32 msr)

{

	BUG_ON(slot >= KVM_NR_SHARED_MSRS);

	if (slot >= shared_msrs_global.nr)

		shared_msrs_global.nr = slot + 1;

	shared_msrs_global.msrs[slot] = msr;