Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Radim Krčmář:
 "ARM:
   - Lazy FPSIMD switching fixes
   - Really disable compat ioctls on architectures that don't want it
   - Disable compat on arm64 (it was never implemented...)
   - Rely on architectural requirements for GICV on GICv3
   - Detect bad alignments in unmap_stage2_range

  x86:
   - Add nested VM entry checks to avoid broken error recovery path
   - Minor documentation fix"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: fix KVM_CAP_HYPERV_TLBFLUSH paragraph number
  kvm: vmx: Nested VM-entry prereqs for event inj.
  KVM: arm64: Prevent KVM_COMPAT from being selected
  KVM: Enforce error in ioctl for compat tasks when !KVM_COMPAT
  KVM: arm/arm64: add WARN_ON if size is not PAGE_SIZE aligned in unmap_stage2_range
  KVM: arm64: Avoid mistaken attempts to save SVE state for vcpus
  KVM: arm64/sve: Fix SVE trap restoration for non-current tasks
  KVM: arm64: Don't mask softirq with IRQs disabled in vcpu_put()
  arm64: Introduce sysreg_clear_set()
  KVM: arm/arm64: Drop resource size check for GICV window

3 files changed, 79 insertions, 0 deletions

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 425e6b8b9547..6aa8499e1f62 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -114,6 +114,7 @@
 #define VMX_MISC_PREEMPTION_TIMER_RATE_MASK	0x0000001f
 #define VMX_MISC_SAVE_EFER_LMA			0x00000020
 #define VMX_MISC_ACTIVITY_HLT			0x00000040
+#define VMX_MISC_ZERO_LEN_INS			0x40000000
 
 /* VMFUNC functions */
 #define VMX_VMFUNC_EPTP_SWITCHING               0x00000001
@@ -351,11 +352,13 @@ enum vmcs_field {
 #define VECTORING_INFO_VALID_MASK       	INTR_INFO_VALID_MASK
 
 #define INTR_TYPE_EXT_INTR              (0 << 8) /* external interrupt */
+#define INTR_TYPE_RESERVED              (1 << 8) /* reserved */
 #define INTR_TYPE_NMI_INTR		(2 << 8) /* NMI */
 #define INTR_TYPE_HARD_EXCEPTION	(3 << 8) /* processor exception */
 #define INTR_TYPE_SOFT_INTR             (4 << 8) /* software interrupt */
 #define INTR_TYPE_PRIV_SW_EXCEPTION	(5 << 8) /* ICE breakpoint - undocumented */
 #define INTR_TYPE_SOFT_EXCEPTION	(6 << 8) /* software exception */
+#define INTR_TYPE_OTHER_EVENT           (7 << 8) /* other event */
 
 /* GUEST_INTERRUPTIBILITY_INFO flags. */
 #define GUEST_INTR_STATE_STI		0x00000001
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 559a12b6184d..1689f433f3a0 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1705,6 +1705,17 @@ static inline bool nested_cpu_has_vmwrite_any_field(struct kvm_vcpu *vcpu)
 		MSR_IA32_VMX_MISC_VMWRITE_SHADOW_RO_FIELDS;
 }
 
+static inline bool nested_cpu_has_zero_length_injection(struct kvm_vcpu *vcpu)
+{
+	return to_vmx(vcpu)->nested.msrs.misc_low & VMX_MISC_ZERO_LEN_INS;
+}
+
+static inline bool nested_cpu_supports_monitor_trap_flag(struct kvm_vcpu *vcpu)
+{
+	return to_vmx(vcpu)->nested.msrs.procbased_ctls_high &
+			CPU_BASED_MONITOR_TRAP_FLAG;
+}
+
 static inline bool nested_cpu_has(struct vmcs12 *vmcs12, u32 bit)
 {
 	return vmcs12->cpu_based_vm_exec_control & bit;
@@ -11620,6 +11631,62 @@ static int check_vmentry_prereqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
 	    !nested_cr3_valid(vcpu, vmcs12->host_cr3))
 		return VMXERR_ENTRY_INVALID_HOST_STATE_FIELD;
 
+	/*
+	 * From the Intel SDM, volume 3:
+	 * Fields relevant to VM-entry event injection must be set properly.
+	 * These fields are the VM-entry interruption-information field, the
+	 * VM-entry exception error code, and the VM-entry instruction length.
+	 */
+	if (vmcs12->vm_entry_intr_info_field & INTR_INFO_VALID_MASK) {
+		u32 intr_info = vmcs12->vm_entry_intr_info_field;
+		u8 vector = intr_info & INTR_INFO_VECTOR_MASK;
+		u32 intr_type = intr_info & INTR_INFO_INTR_TYPE_MASK;
+		bool has_error_code = intr_info & INTR_INFO_DELIVER_CODE_MASK;
+		bool should_have_error_code;
+		bool urg = nested_cpu_has2(vmcs12,
+					   SECONDARY_EXEC_UNRESTRICTED_GUEST);
+		bool prot_mode = !urg || vmcs12->guest_cr0 & X86_CR0_PE;
+
+		/* VM-entry interruption-info field: interruption type */
+		if (intr_type == INTR_TYPE_RESERVED ||
+		    (intr_type == INTR_TYPE_OTHER_EVENT &&
+		     !nested_cpu_supports_monitor_trap_flag(vcpu)))
+			return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
+		/* VM-entry interruption-info field: vector */
+		if ((intr_type == INTR_TYPE_NMI_INTR && vector != NMI_VECTOR) ||
+		    (intr_type == INTR_TYPE_HARD_EXCEPTION && vector > 31) ||
+		    (intr_type == INTR_TYPE_OTHER_EVENT && vector != 0))
+			return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
+		/* VM-entry interruption-info field: deliver error code */
+		should_have_error_code =
+			intr_type == INTR_TYPE_HARD_EXCEPTION && prot_mode &&
+			x86_exception_has_error_code(vector);
+		if (has_error_code != should_have_error_code)
+			return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
+		/* VM-entry exception error code */
+		if (has_error_code &&
+		    vmcs12->vm_entry_exception_error_code & GENMASK(31, 15))
+			return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
+		/* VM-entry interruption-info field: reserved bits */
+		if (intr_info & INTR_INFO_RESVD_BITS_MASK)
+			return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
+		/* VM-entry instruction length */
+		switch (intr_type) {
+		case INTR_TYPE_SOFT_EXCEPTION:
+		case INTR_TYPE_SOFT_INTR:
+		case INTR_TYPE_PRIV_SW_EXCEPTION:
+			if ((vmcs12->vm_entry_instruction_len > 15) ||
+			    (vmcs12->vm_entry_instruction_len == 0 &&
+			     !nested_cpu_has_zero_length_injection(vcpu)))
+				return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+		}
+	}
+
 	return 0;
 }
 
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 331993c49dae..257f27620bc2 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -110,6 +110,15 @@ static inline bool is_la57_mode(struct kvm_vcpu *vcpu)
 #endif
 }
 
+static inline bool x86_exception_has_error_code(unsigned int vector)
+{
+	static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
+			BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
+			BIT(PF_VECTOR) | BIT(AC_VECTOR);
+
+	return (1U << vector) & exception_has_error_code;
+}
+
 static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.walk_mmu == &vcpu->arch.nested_mmu;