usb: usb_get_configuration() obeys authorization

If called and the device is not authorized to be used, then we don't
allow reading the configurations.

Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index cb69aa1e02e8762913e1d68901fb64495b68d8d0..1a8edcee7f303af3d1f3a5c6931ca5f9a7620dc0 100644 (file)
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -507,18 +507,30 @@ void usb_destroy_configuration(struct usb_device *dev)
 }
 
 
-// hub-only!! ... and only in reset path, or usb_new_device()
-// (used by real hubs and virtual root hubs)
+/*
+ * Get the USB config descriptors, cache and parse'em
+ *
+ * hub-only!! ... and only in reset path, or usb_new_device()
+ * (used by real hubs and virtual root hubs)
+ *
+ * NOTE: if this is a WUSB device and is not authorized, we skip the
+ *       whole thing. A non-authorized USB device has no
+ *       configurations.
+ */
 int usb_get_configuration(struct usb_device *dev)
 {
        struct device *ddev = &dev->dev;
        int ncfg = dev->descriptor.bNumConfigurations;
-       int result = -ENOMEM;
+       int result = 0;
        unsigned int cfgno, length;
        unsigned char *buffer;
        unsigned char *bigbuffer;
        struct usb_config_descriptor *desc;
 
+       cfgno = 0;
+       if (dev->authorized == 0)       /* Not really an error */
+               goto out_not_authorized;
+       result = -ENOMEM;
        if (ncfg > USB_MAXCONFIG) {
                dev_warn(ddev, "too many configurations: %d, "
                    "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
@@ -545,14 +557,15 @@ int usb_get_configuration(struct usb_device *dev)
                goto err2;
        desc = (struct usb_config_descriptor *)buffer;
 
-       for (cfgno = 0; cfgno < ncfg; cfgno++) {
+       result = 0;
+       for (; cfgno < ncfg; cfgno++) {
                /* We grab just the first descriptor so we know how long
                 * the whole configuration is */
                result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
                    buffer, USB_DT_CONFIG_SIZE);
                if (result < 0) {
                        dev_err(ddev, "unable to read config index %d "
-                           "descriptor/%s\n", cfgno, "start");
+                           "descriptor/%s: %d\n", cfgno, "start", result);
                        dev_err(ddev, "chopping to %d config(s)\n", cfgno);
                        dev->descriptor.bNumConfigurations = cfgno;
                        break;
@@ -599,6 +612,7 @@ int usb_get_configuration(struct usb_device *dev)
 
 err:
        kfree(buffer);
+out_not_authorized:
        dev->descriptor.bNumConfigurations = cfgno;
 err2:
        if (result == -ENOMEM)