1 files changed, 41 insertions, 17 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f37f0c72b22a..53d43d22a84b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3973,13 +3973,14 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		mutex_unlock(&kvm->lock);
 		break;
 	case KVM_XEN_HVM_CONFIG: {
+		struct kvm_xen_hvm_config xhc;
 		r = -EFAULT;
-		if (copy_from_user(&kvm->arch.xen_hvm_config, argp,
-				   sizeof(struct kvm_xen_hvm_config)))
+		if (copy_from_user(&xhc, argp, sizeof(xhc)))
 			goto out;
 		r = -EINVAL;
-		if (kvm->arch.xen_hvm_config.flags)
+		if (xhc.flags)
 			goto out;
+		memcpy(&kvm->arch.xen_hvm_config, &xhc, sizeof(xhc));
 		r = 0;
 		break;
 	}
@@ -4244,11 +4245,10 @@ static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt,
 	return X86EMUL_CONTINUE;
 }
 
-int kvm_read_guest_virt(struct x86_emulate_ctxt *ctxt,
+int kvm_read_guest_virt(struct kvm_vcpu *vcpu,
 			       gva_t addr, void *val, unsigned int bytes,
 			       struct x86_exception *exception)
 {
-	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
 	u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0;
 
 	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access,
@@ -4256,12 +4256,17 @@ int kvm_read_guest_virt(struct x86_emulate_ctxt *ctxt,
 }
 EXPORT_SYMBOL_GPL(kvm_read_guest_virt);
 
-static int kvm_read_guest_virt_system(struct x86_emulate_ctxt *ctxt,
-				      gva_t addr, void *val, unsigned int bytes,
-				      struct x86_exception *exception)
+static int emulator_read_std(struct x86_emulate_ctxt *ctxt,
+			     gva_t addr, void *val, unsigned int bytes,
+			     struct x86_exception *exception, bool system)
 {
 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, 0, exception);
+	u32 access = 0;
+
+	if (!system && kvm_x86_ops->get_cpl(vcpu) == 3)
+		access |= PFERR_USER_MASK;
+
+	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, exception);
 }
 
 static int kvm_read_guest_phys_system(struct x86_emulate_ctxt *ctxt,
@@ -4273,18 +4278,16 @@ static int kvm_read_guest_phys_system(struct x86_emulate_ctxt *ctxt,
 	return r < 0 ? X86EMUL_IO_NEEDED : X86EMUL_CONTINUE;
 }
 
-int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
-				       gva_t addr, void *val,
-				       unsigned int bytes,
-				       struct x86_exception *exception)
+static int kvm_write_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
+				      struct kvm_vcpu *vcpu, u32 access,
+				      struct x86_exception *exception)
 {
-	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
 	void *data = val;
 	int r = X86EMUL_CONTINUE;
 
 	while (bytes) {
 		gpa_t gpa =  vcpu->arch.walk_mmu->gva_to_gpa(vcpu, addr,
-							     PFERR_WRITE_MASK,
+							     access,
 							     exception);
 		unsigned offset = addr & (PAGE_SIZE-1);
 		unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset);
@@ -4305,6 +4308,27 @@ int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
 out:
 	return r;
 }
+
+static int emulator_write_std(struct x86_emulate_ctxt *ctxt, gva_t addr, void *val,
+			      unsigned int bytes, struct x86_exception *exception,
+			      bool system)
+{
+	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
+	u32 access = PFERR_WRITE_MASK;
+
+	if (!system && kvm_x86_ops->get_cpl(vcpu) == 3)
+		access |= PFERR_USER_MASK;
+
+	return kvm_write_guest_virt_helper(addr, val, bytes, vcpu,
+					   access, exception);
+}
+
+int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val,
+				unsigned int bytes, struct x86_exception *exception)
+{
+	return kvm_write_guest_virt_helper(addr, val, bytes, vcpu,
+					   PFERR_WRITE_MASK, exception);
+}
 EXPORT_SYMBOL_GPL(kvm_write_guest_virt_system);
 
 static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
@@ -5024,8 +5048,8 @@ static void emulator_set_hflags(struct x86_emulate_ctxt *ctxt, unsigned emul_fla
 static const struct x86_emulate_ops emulate_ops = {
 	.read_gpr            = emulator_read_gpr,
 	.write_gpr           = emulator_write_gpr,
-	.read_std            = kvm_read_guest_virt_system,
-	.write_std           = kvm_write_guest_virt_system,
+	.read_std            = emulator_read_std,
+	.write_std           = emulator_write_std,
 	.read_phys           = kvm_read_guest_phys_system,
 	.fetch               = kvm_fetch_guest_virt,
 	.read_emulated       = emulator_read_emulated,