diff options
| -rw-r--r-- | sound/usb/midi2.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/sound/usb/midi2.c b/sound/usb/midi2.c index 2785600d2312..04aeb9052f13 100644 --- a/sound/usb/midi2.c +++ b/sound/usb/midi2.c @@ -496,15 +496,17 @@ static void *find_usb_ms_endpoint_descriptor(struct usb_host_endpoint *hostep, while (extralen > 3) { struct usb_ms_endpoint_descriptor *ms_ep = (struct usb_ms_endpoint_descriptor *)extra; + int length = ms_ep->bLength; - if (ms_ep->bLength > 3 && + if (!length || length > extralen) + break; + + if (length > 3 && ms_ep->bDescriptorType == USB_DT_CS_ENDPOINT && ms_ep->bDescriptorSubtype == subtype) return ms_ep; - if (!extra[0]) - break; - extralen -= extra[0]; - extra += extra[0]; + extralen -= length; + extra += length; } return NULL; } |