Commit 38a08644 authored by Hans de Goede's avatar Hans de Goede Committed by Greg Kroah-Hartman
Browse files

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

commit b4f17a488ae2e09bfcf95c0e0b4219c246f1116a upstream.

While reading the config parsing code I noticed this check is missing, without
this check config->desc.wTotalLength can end up with a value larger then the
dev->rawdescriptors length for the config, and when userspace then tries to
get the rawdescriptors bad things may happen.
Signed-off-by: default avatarHans de Goede <>
Signed-off-by: default avatarGreg Kroah-Hartman <>
parent e200d6be
......@@ -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);
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