On 64 bit systems the agp_info struct has a hole between ->agp_mode and
->aper_base.  We need to clear it to avoid leaking stack information to
userspace.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/char/agp/frontend.c b/drivers/char/agp/frontend.c
index 2e04433..3fbce33 100644
--- a/drivers/char/agp/frontend.c
+++ b/drivers/char/agp/frontend.c
@@ -729,6 +729,7 @@ static int agpioc_info_wrap(struct agp_file_private *priv, void __user *arg)
 
 	agp_copy_info(agp_bridge, &kerninfo);
 
+	memset(&userinfo, 0, sizeof(userinfo));
 	userinfo.version.major = kerninfo.version.major;
 	userinfo.version.minor = kerninfo.version.minor;
 	userinfo.bridge_id = kerninfo.device->vendor |