USB: idmouse: fix NULL-deref at probe

BugLink: http://bugs.launchpad.net/bugs/1677600
commit b0addd3fa6bcd119be9428996d5d4522479ab240 upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

diff --git a/drivers/usb/misc/idmouse.c b/drivers/usb/misc/idmouse.c
index 4e38683c653cf3b9dc614b2b3f4f1cf721cfac14..6d4e7578571085130ec7a476b73f6173194819fd 100644 (file)
--- a/drivers/usb/misc/idmouse.c
+++ b/drivers/usb/misc/idmouse.c
@@ -346,6 +346,9 @@ static int idmouse_probe(struct usb_interface *interface,
        if (iface_desc->desc.bInterfaceClass != 0x0A)
                return -ENODEV;
 
+       if (iface_desc->desc.bNumEndpoints < 1)
+               return -ENODEV;
+
        /* allocate memory for our device state and initialize it */
        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
        if (dev == NULL)