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nSVM: Check addresses of MSR and IO permission maps

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According to section "Canonicalization and Consistency Checks" in APM vol 2,
the following guest state is illegal:

    "The MSR or IOIO intercept tables extend to a physical address that
     is greater than or equal to the maximum supported physical address."

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <20210412215611.110095-5-krish.sadhukhan@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Krish Sadhukhan 2021-04-12 17:56:08 -04:00 committed by Paolo Bonzini
parent 47903dc10e
commit ee695f22b5
1 changed files with 22 additions and 3 deletions
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25
arch/x86/kvm/svm/nested.c
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@ -215,7 +215,19 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
return true;
}
static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
/*
* Bits 11:0 of bitmap address are ignored by hardware
*/
static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size)
{
u64 addr = PAGE_ALIGN(pa);
return kvm_vcpu_is_legal_gpa(vcpu, addr) &&
kvm_vcpu_is_legal_gpa(vcpu, addr + size - 1);
}
static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu,
struct vmcb_control_area *control)
{
if (CC(!vmcb_is_intercept(control, INTERCEPT_VMRUN)))
return false;
@ -226,6 +238,13 @@ static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
if (CC((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && !npt_enabled))
return false;
if (CC(!nested_svm_check_bitmap_pa(vcpu, control->msrpm_base_pa,
MSRPM_SIZE)))
return false;
if (CC(!nested_svm_check_bitmap_pa(vcpu, control->iopm_base_pa,
IOPM_SIZE)))
return false;
return true;
}
@ -604,7 +623,7 @@ int nested_svm_vmrun(struct kvm_vcpu *vcpu)
nested_load_control_from_vmcb12(svm, &vmcb12->control);
if (!nested_vmcb_valid_sregs(vcpu, &vmcb12->save) ||
!nested_vmcb_check_controls(&svm->nested.ctl)) {
!nested_vmcb_check_controls(vcpu, &svm->nested.ctl)) {
vmcb12->control.exit_code = SVM_EXIT_ERR;
vmcb12->control.exit_code_hi = 0;
vmcb12->control.exit_info_1 = 0;
@ -1252,7 +1271,7 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
goto out_free;
ret = -EINVAL;
if (!nested_vmcb_check_controls(ctl))
if (!nested_vmcb_check_controls(vcpu, ctl))
goto out_free;
/*