From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Fri, 23 Sep 2011 06:19:46 +0000 Subject: [patch] agp: potential info leak in compat_agpioc_info_wrap() Message-Id: <20110923061945.GC4387@elgon.mountain> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: David Airlie Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Smatch has a new check for Rosenberg type information leaks where structs are copied to the user with uninitialized stack data in them. The agp_info32 struct has a 4 byte hole in it so we need to clear that before copying it to userspace. struct agp_info32 { struct agp_version version; /* 0 0 */ /* XXX 4 bytes hole, try to pack */ u32 bridge_id; /* 4 4 */ Signed-off-by: Dan Carpenter diff --git a/drivers/char/agp/compat_ioctl.c b/drivers/char/agp/compat_ioctl.c index a48e05b..0509497 100644 --- a/drivers/char/agp/compat_ioctl.c +++ b/drivers/char/agp/compat_ioctl.c @@ -42,6 +42,8 @@ static int compat_agpioc_info_wrap(struct agp_file_private *priv, void __user *a 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 |