[PATCH 2/5] KVM: nVMX: Verify the VMX controls MSRs with the global capability when setting VMX MSRs

From: Chenyi Qiang
Date: Fri Aug 28 2020 - 04:55:14 EST


When setting the nested VMX MSRs, verify it with the values in
vmcs_config.nested_vmx_msrs, which reflects the global capability of
VMX controls MSRs.

Signed-off-by: Chenyi Qiang <chenyi.qiang@xxxxxxxxx>
---
arch/x86/kvm/vmx/nested.c | 71 ++++++++++++++++++++++++++++-----------
1 file changed, 51 insertions(+), 20 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 6e0e71f4d45f..47bee53e235a 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -1234,7 +1234,7 @@ static int vmx_restore_vmx_basic(struct vcpu_vmx *vmx, u64 data)
BIT_ULL(49) | BIT_ULL(54) | BIT_ULL(55) |
/* reserved */
BIT_ULL(31) | GENMASK_ULL(47, 45) | GENMASK_ULL(63, 56);
- u64 vmx_basic = vmx->nested.msrs.basic;
+ u64 vmx_basic = vmcs_config.nested.basic;

if (!is_bitwise_subset(vmx_basic, data, feature_and_reserved))
return -EINVAL;
@@ -1265,24 +1265,24 @@ vmx_restore_control_msr(struct vcpu_vmx *vmx, u32 msr_index, u64 data)

switch (msr_index) {
case MSR_IA32_VMX_TRUE_PINBASED_CTLS:
- lowp = &vmx->nested.msrs.pinbased_ctls_low;
- highp = &vmx->nested.msrs.pinbased_ctls_high;
+ lowp = &vmcs_config.nested.pinbased_ctls_low;
+ highp = &vmcs_config.nested.pinbased_ctls_high;
break;
case MSR_IA32_VMX_TRUE_PROCBASED_CTLS:
- lowp = &vmx->nested.msrs.procbased_ctls_low;
- highp = &vmx->nested.msrs.procbased_ctls_high;
+ lowp = &vmcs_config.nested.procbased_ctls_low;
+ highp = &vmcs_config.nested.procbased_ctls_high;
break;
case MSR_IA32_VMX_TRUE_EXIT_CTLS:
- lowp = &vmx->nested.msrs.exit_ctls_low;
- highp = &vmx->nested.msrs.exit_ctls_high;
+ lowp = &vmcs_config.nested.exit_ctls_low;
+ highp = &vmcs_config.nested.exit_ctls_high;
break;
case MSR_IA32_VMX_TRUE_ENTRY_CTLS:
- lowp = &vmx->nested.msrs.entry_ctls_low;
- highp = &vmx->nested.msrs.entry_ctls_high;
+ lowp = &vmcs_config.nested.entry_ctls_low;
+ highp = &vmcs_config.nested.entry_ctls_high;
break;
case MSR_IA32_VMX_PROCBASED_CTLS2:
- lowp = &vmx->nested.msrs.secondary_ctls_low;
- highp = &vmx->nested.msrs.secondary_ctls_high;
+ lowp = &vmcs_config.nested.secondary_ctls_low;
+ highp = &vmcs_config.nested.secondary_ctls_high;
break;
default:
BUG();
@@ -1298,8 +1298,30 @@ vmx_restore_control_msr(struct vcpu_vmx *vmx, u32 msr_index, u64 data)
if (!is_bitwise_subset(supported, data, GENMASK_ULL(63, 32)))
return -EINVAL;

- *lowp = data;
- *highp = data >> 32;
+ switch (msr_index) {
+ case MSR_IA32_VMX_TRUE_PINBASED_CTLS:
+ vmx->nested.msrs.pinbased_ctls_low = data;
+ vmx->nested.msrs.pinbased_ctls_high = data >> 32;
+ break;
+ case MSR_IA32_VMX_TRUE_PROCBASED_CTLS:
+ vmx->nested.msrs.procbased_ctls_low = data;
+ vmx->nested.msrs.procbased_ctls_high = data >> 32;
+ break;
+ case MSR_IA32_VMX_TRUE_EXIT_CTLS:
+ vmx->nested.msrs.exit_ctls_low = data;
+ vmx->nested.msrs.exit_ctls_high = data >> 32;
+ break;
+ case MSR_IA32_VMX_TRUE_ENTRY_CTLS:
+ vmx->nested.msrs.entry_ctls_low = data;
+ vmx->nested.msrs.entry_ctls_high = data >> 32;
+ break;
+ case MSR_IA32_VMX_PROCBASED_CTLS2:
+ vmx->nested.msrs.secondary_ctls_low = data;
+ vmx->nested.msrs.secondary_ctls_high = data >> 32;
+ break;
+ default:
+ BUG();
+ }
return 0;
}

@@ -1313,8 +1335,8 @@ static int vmx_restore_vmx_misc(struct vcpu_vmx *vmx, u64 data)
GENMASK_ULL(13, 9) | BIT_ULL(31);
u64 vmx_misc;

- vmx_misc = vmx_control_msr(vmx->nested.msrs.misc_low,
- vmx->nested.msrs.misc_high);
+ vmx_misc = vmx_control_msr(vmcs_config.nested.misc_low,
+ vmcs_config.nested.misc_high);

if (!is_bitwise_subset(vmx_misc, data, feature_and_reserved_bits))
return -EINVAL;
@@ -1344,8 +1366,8 @@ static int vmx_restore_vmx_ept_vpid_cap(struct vcpu_vmx *vmx, u64 data)
{
u64 vmx_ept_vpid_cap;

- vmx_ept_vpid_cap = vmx_control_msr(vmx->nested.msrs.ept_caps,
- vmx->nested.msrs.vpid_caps);
+ vmx_ept_vpid_cap = vmx_control_msr(vmcs_config.nested.ept_caps,
+ vmcs_config.nested.vpid_caps);

/* Every bit is either reserved or a feature bit. */
if (!is_bitwise_subset(vmx_ept_vpid_cap, data, -1ULL))
@@ -1362,10 +1384,10 @@ static int vmx_restore_fixed0_msr(struct vcpu_vmx *vmx, u32 msr_index, u64 data)

switch (msr_index) {
case MSR_IA32_VMX_CR0_FIXED0:
- msr = &vmx->nested.msrs.cr0_fixed0;
+ msr = &vmcs_config.nested.cr0_fixed0;
break;
case MSR_IA32_VMX_CR4_FIXED0:
- msr = &vmx->nested.msrs.cr4_fixed0;
+ msr = &vmcs_config.nested.cr4_fixed0;
break;
default:
BUG();
@@ -1378,7 +1400,16 @@ static int vmx_restore_fixed0_msr(struct vcpu_vmx *vmx, u32 msr_index, u64 data)
if (!is_bitwise_subset(data, *msr, -1ULL))
return -EINVAL;

- *msr = data;
+ switch (msr_index) {
+ case MSR_IA32_VMX_CR0_FIXED0:
+ vmx->nested.msrs.cr0_fixed0 = data;
+ break;
+ case MSR_IA32_VMX_CR4_FIXED0:
+ vmx->nested.msrs.cr4_fixed0 = data;
+ break;
+ default:
+ BUG();
+ }
return 0;
}

--
2.17.1