From: Avi Kivity <avi@qumranet.com>
Date: Wed, 7 Mar 2007 11:11:17 +0000 (+0200)
Subject: KVM: Future-proof argument-less ioctls
X-Git-Tag: v2.6.22-rc1~1008^2~47
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f0fe510864a4520a85dfa35ae14f5f376c56efc7;p=linux-2.6

KVM: Future-proof argument-less ioctls

Some ioctls ignore their arguments.  By requiring them to be zero now,
we allow a nonzero value to have some special meaning in the future.

Signed-off-by: Avi Kivity <avi@qumranet.com>
---

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index cba0b87c34..ba7f43a445 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -2169,6 +2169,9 @@ static long kvm_vcpu_ioctl(struct file *filp,
 
 	switch (ioctl) {
 	case KVM_RUN:
+		r = -EINVAL;
+		if (arg)
+			goto out;
 		r = kvm_vcpu_ioctl_run(vcpu, vcpu->run);
 		break;
 	case KVM_GET_REGS: {
@@ -2440,9 +2443,15 @@ static long kvm_dev_ioctl(struct file *filp,
 
 	switch (ioctl) {
 	case KVM_GET_API_VERSION:
+		r = -EINVAL;
+		if (arg)
+			goto out;
 		r = KVM_API_VERSION;
 		break;
 	case KVM_CREATE_VM:
+		r = -EINVAL;
+		if (arg)
+			goto out;
 		r = kvm_dev_ioctl_create_vm();
 		break;
 	case KVM_GET_MSR_INDEX_LIST: {