usb: core: fix information leak to userland

Structure usbdevfs_connectinfo is copied to userland with padding byted
after "slow" field uninitialized.  It leads to leaking of contents of
kernel stack memory.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index f1aaff6202a5..045bb4b823e1 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -965,10 +965,11 @@ static int proc_getdriver(struct dev_state *ps, void __user *arg)
 
 static int proc_connectinfo(struct dev_state *ps, void __user *arg)
 {
-        struct usbdevfs_connectinfo ci;
+        struct usbdevfs_connectinfo ci = {
+                .devnum = ps->dev->devnum,
+                .slow = ps->dev->speed == USB_SPEED_LOW
+        };
 
-        ci.devnum = ps->dev->devnum;
-        ci.slow = ps->dev->speed == USB_SPEED_LOW;
         if (copy_to_user(arg, &ci, sizeof(ci)))
                 return -EFAULT;
         return 0;