KVM: nVMX: check for invalid hdr.vmx.flags

hdr.vmx.flags is meant for future extensions to the ABI, rejecting
invalid flags is necessary to avoid broken half-loads of the
nVMX state.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2020-07-27 08:55:09 -04:00
parent 0f02bd0ade
commit 5e105c88ab
2 changed files with 16 additions and 0 deletions

View File

@ -6079,6 +6079,9 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu,
~(KVM_STATE_NESTED_SMM_GUEST_MODE | KVM_STATE_NESTED_SMM_VMXON))
return -EINVAL;
if (kvm_state->hdr.vmx.flags & ~KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE)
return -EINVAL;
/*
* SMM temporarily disables VMX, so we cannot be in guest mode,
* nor can VMLAUNCH/VMRESUME be pending. Outside SMM, SMM flags

View File

@ -146,6 +146,11 @@ void test_vmx_nested_state(struct kvm_vm *vm)
state->hdr.vmx.smm.flags = 1;
test_nested_state_expect_einval(vm, state);
/* Invalid flags are rejected. */
set_default_vmx_state(state, state_sz);
state->hdr.vmx.flags = ~0;
test_nested_state_expect_einval(vm, state);
/* It is invalid to have vmxon_pa == -1ull and vmcs_pa != -1ull. */
set_default_vmx_state(state, state_sz);
state->hdr.vmx.vmxon_pa = -1ull;
@ -206,6 +211,14 @@ void test_vmx_nested_state(struct kvm_vm *vm)
state->flags = 0;
test_nested_state(vm, state);
/* Invalid flags are rejected, even if no VMCS loaded. */
set_default_vmx_state(state, state_sz);
state->size = sizeof(*state);
state->flags = 0;
state->hdr.vmx.vmcs12_pa = -1;
state->hdr.vmx.flags = ~0;
test_nested_state_expect_einval(vm, state);
/* vmxon_pa cannot be the same address as vmcs_pa. */
set_default_vmx_state(state, state_sz);
state->hdr.vmx.vmxon_pa = 0;