USB: usbfs: fix potential infoleak in devio

The stack object “ci” has a total size of 8 bytes. Its last 3 bytes
are padding bytes which are not initialized and leaked to userland
via “copy_to_user”.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 681fef8380eb818c0b845fca5d2ab1dcbab114ee)
CVE-2016-4482
BugLink: https://bugs.launchpad.net/bugs/1578493
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index 38ae877c46e3124eb07c2a46ddd33bc66ac54d93..3ffb01ff654978a9aa7f5ba62317a23a95aecade 100644 (file)
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -1203,10 +1203,11 @@ static int proc_getdriver(struct usb_dev_state *ps, void __user *arg)
 
 static int proc_connectinfo(struct usb_dev_state *ps, void __user *arg)
 {
-       struct usbdevfs_connectinfo ci = {
-               .devnum = ps->dev->devnum,
-               .slow = ps->dev->speed == USB_SPEED_LOW
-       };
+       struct usbdevfs_connectinfo ci;
+
+       memset(&ci, 0, sizeof(ci));
+       ci.devnum = ps->dev->devnum;
+       ci.slow = ps->dev->speed == USB_SPEED_LOW;
 
        if (copy_to_user(arg, &ci, sizeof(ci)))
                return -EFAULT;