diff options
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 6 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 28 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 34 |
3 files changed, 49 insertions, 19 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 0611dac70c25..302a4669c5a1 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1734,6 +1734,11 @@ static void svm_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt) vmcb_mark_dirty(svm->vmcb, VMCB_DT); } +static bool svm_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) +{ + return true; +} + void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) { struct vcpu_svm *svm = to_svm(vcpu); @@ -4596,6 +4601,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .set_segment = svm_set_segment, .get_cpl = svm_get_cpl, .get_cs_db_l_bits = kvm_get_cs_db_l_bits, + .is_valid_cr0 = svm_is_valid_cr0, .set_cr0 = svm_set_cr0, .is_valid_cr4 = svm_is_valid_cr4, .set_cr4 = svm_set_cr4, diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0841f9a34d1c..89744ee06101 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2894,6 +2894,15 @@ static void enter_rmode(struct kvm_vcpu *vcpu) struct vcpu_vmx *vmx = to_vmx(vcpu); struct kvm_vmx *kvm_vmx = to_kvm_vmx(vcpu->kvm); + /* + * KVM should never use VM86 to virtualize Real Mode when L2 is active, + * as using VM86 is unnecessary if unrestricted guest is enabled, and + * if unrestricted guest is disabled, VM-Enter (from L1) with CR0.PG=0 + * should VM-Fail and KVM should reject userspace attempts to stuff + * CR0.PG=0 when L2 is active. + */ + WARN_ON_ONCE(is_guest_mode(vcpu)); + vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_TR], VCPU_SREG_TR); vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_ES], VCPU_SREG_ES); vmx_get_segment(vcpu, &vmx->rmode.segs[VCPU_SREG_DS], VCPU_SREG_DS); @@ -3084,6 +3093,17 @@ void ept_save_pdptrs(struct kvm_vcpu *vcpu) #define CR3_EXITING_BITS (CPU_BASED_CR3_LOAD_EXITING | \ CPU_BASED_CR3_STORE_EXITING) +static bool vmx_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) +{ + if (is_guest_mode(vcpu)) + return nested_guest_cr0_valid(vcpu, cr0); + + if (to_vmx(vcpu)->nested.vmxon) + return nested_host_cr0_valid(vcpu, cr0); + + return true; +} + void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) { struct vcpu_vmx *vmx = to_vmx(vcpu); @@ -5027,18 +5047,11 @@ static int handle_set_cr0(struct kvm_vcpu *vcpu, unsigned long val) val = (val & ~vmcs12->cr0_guest_host_mask) | (vmcs12->guest_cr0 & vmcs12->cr0_guest_host_mask); - if (!nested_guest_cr0_valid(vcpu, val)) - return 1; - if (kvm_set_cr0(vcpu, val)) return 1; vmcs_writel(CR0_READ_SHADOW, orig_val); return 0; } else { - if (to_vmx(vcpu)->nested.vmxon && - !nested_host_cr0_valid(vcpu, val)) - return 1; - return kvm_set_cr0(vcpu, val); } } @@ -7744,6 +7757,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .set_segment = vmx_set_segment, .get_cpl = vmx_get_cpl, .get_cs_db_l_bits = vmx_get_cs_db_l_bits, + .is_valid_cr0 = vmx_is_valid_cr0, .set_cr0 = vmx_set_cr0, .is_valid_cr4 = vmx_is_valid_cr4, .set_cr4 = vmx_set_cr4, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 7e1e3bc74562..285ba12be8ce 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -876,6 +876,22 @@ out: } EXPORT_SYMBOL_GPL(load_pdptrs); +static bool kvm_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) +{ +#ifdef CONFIG_X86_64 + if (cr0 & 0xffffffff00000000UL) + return false; +#endif + + if ((cr0 & X86_CR0_NW) && !(cr0 & X86_CR0_CD)) + return false; + + if ((cr0 & X86_CR0_PG) && !(cr0 & X86_CR0_PE)) + return false; + + return static_call(kvm_x86_is_valid_cr0)(vcpu, cr0); +} + void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned long cr0) { if ((cr0 ^ old_cr0) & X86_CR0_PG) { @@ -898,20 +914,13 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) unsigned long old_cr0 = kvm_read_cr0(vcpu); unsigned long pdptr_bits = X86_CR0_CD | X86_CR0_NW | X86_CR0_PG; - cr0 |= X86_CR0_ET; - -#ifdef CONFIG_X86_64 - if (cr0 & 0xffffffff00000000UL) + if (!kvm_is_valid_cr0(vcpu, cr0)) return 1; -#endif - - cr0 &= ~CR0_RESERVED_BITS; - if ((cr0 & X86_CR0_NW) && !(cr0 & X86_CR0_CD)) - return 1; + cr0 |= X86_CR0_ET; - if ((cr0 & X86_CR0_PG) && !(cr0 & X86_CR0_PE)) - return 1; + /* Write to CR0 reserved bits are ignored, even on Intel. */ + cr0 &= ~CR0_RESERVED_BITS; #ifdef CONFIG_X86_64 if ((vcpu->arch.efer & EFER_LME) && !is_paging(vcpu) && @@ -10643,7 +10652,8 @@ static bool kvm_is_valid_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) return false; } - return kvm_is_valid_cr4(vcpu, sregs->cr4); + return kvm_is_valid_cr4(vcpu, sregs->cr4) && + kvm_is_valid_cr0(vcpu, sregs->cr0); } static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs, |