KVM: Fix xsave and xcr save/restore memory leak

We allocate temporary kernel buffers for these structures, but never free them.
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/x86.c

@@ -2437,6 +2437,8 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 	void __user *argp = (void __user *)arg;
 	int r;
 	struct kvm_lapic_state *lapic = NULL;
+	struct kvm_xsave *xsave = NULL;
+	struct kvm_xcrs *xcrs = NULL;
 
 	switch (ioctl) {
 	case KVM_GET_LAPIC: {
@@ -2632,8 +2634,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_GET_XSAVE: {
-		struct kvm_xsave *xsave;
-
 		xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xsave)
@@ -2648,8 +2648,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_SET_XSAVE: {
-		struct kvm_xsave *xsave;
-
 		xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xsave)
@@ -2663,8 +2661,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_GET_XCRS: {
-		struct kvm_xcrs *xcrs;
-
 		xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xcrs)
@@ -2680,8 +2676,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_SET_XCRS: {
-		struct kvm_xcrs *xcrs;
-
 		xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
 		r = -ENOMEM;
 		if (!xcrs)
@@ -2700,6 +2694,8 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 	}
 out:
 	kfree(lapic);
+	kfree(xsave);
+	kfree(xcrs);
 	return r;
 }