[PATCH 3.16 276/305] USB: usbfs: fix potential infoleak in devio

Ben Hutchings
2016-08-14T18:13:49Z

From: Kangjie Lu <kangjielu@gmail.com>

commit 681fef8380eb818c0b845fca5d2ab1dcbab114ee upstream.

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>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/core/devio.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -1202,10 +1202,11 @@ static int proc_getdriver(struct usb_dev

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;