[PATCH] Reintroduce proper returning of -EFAULT to hiddev.c

One of my earlier patches backed out a change that fixed all
copy_to_user calls to properly return -EFAULT if needed. This puts the
change back in.

drivers/usb/input/hiddev.c

@@ -399,10 +399,12 @@ static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd
 		dinfo.product = dev->descriptor.idProduct;
 		dinfo.version = dev->descriptor.bcdDevice;
 		dinfo.num_applications = hid->maxapplication;
-		return copy_to_user((void *) arg, &dinfo, sizeof(dinfo));
+		if (copy_to_user((void *) arg, &dinfo, sizeof(dinfo)))
+			return -EFAULT;
 
 	case HIDIOCGFLAG:
-		return put_user(list->flags, (int *) arg);
+		if (put_user(list->flags, (int *) arg))
+			return -EFAULT;
 
 	case HIDIOCSFLAG:
 		{
@@ -488,7 +490,8 @@ static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd
 
 		rinfo.num_fields = report->maxfield;
 
-		return copy_to_user((void *) arg, &rinfo, sizeof(rinfo));
+		if (copy_to_user((void *) arg, &rinfo, sizeof(rinfo)))
+			return -EFAULT;
 
 	case HIDIOCGFIELDINFO:
 		if (copy_from_user(&finfo, (void *) arg, sizeof(finfo)))
@@ -518,7 +521,8 @@ static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd
 		finfo.unit_exponent = field->unit_exponent;
 		finfo.unit = field->unit;
 
-		return copy_to_user((void *) arg, &finfo, sizeof(finfo));
+		if (copy_to_user((void *) arg, &finfo, sizeof(finfo)))
+			return -EFAULT;
 
 	case HIDIOCGUCODE:
 		if (copy_from_user(&uref, (void *) arg, sizeof(uref)))
@@ -538,7 +542,8 @@ static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd
 
 		uref.usage_code = field->usage[uref.usage_index].hid;
 
-		return copy_to_user((void *) arg, &uref, sizeof(uref));
+		if (copy_to_user((void *) arg, &uref, sizeof(uref)))
+			return -EFAULT;
 
 	case HIDIOCGUSAGE:
 	case HIDIOCSUSAGE:
@@ -570,7 +575,8 @@ static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd
 		switch (cmd) {
 			case HIDIOCGUSAGE:
 				uref.value = field->value[uref.usage_index];
-				return copy_to_user((void *) arg, &uref, sizeof(uref));
+				if (copy_to_user((void *) arg, &uref, sizeof(uref)))
+					return -EFAULT;
 				return 0;
 
 			case HIDIOCSUSAGE: