usb: config->desc.bLength may not exceed amount of data returned by the device

[~andy/linux] / drivers / usb / core / config.c

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 7199adccf44488dc487641de2a085361bdaa0041..a6b2cabe7930eff53504448ab36d48b8786f3f98 100644 (file)
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -424,7 +424,8 @@ static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 
        memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
        if (config->desc.bDescriptorType != USB_DT_CONFIG ||
-           config->desc.bLength < USB_DT_CONFIG_SIZE) {
+           config->desc.bLength < USB_DT_CONFIG_SIZE ||
+           config->desc.bLength > size) {
                dev_err(ddev, "invalid descriptor for config index %d: "
                    "type = 0x%X, length = %d\n", cfgidx,
                    config->desc.bDescriptorType, config->desc.bLength);