From c4ed8c66d79d707d89fe732ff5b97739edf1ba62 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Thu, 8 Oct 2009 19:38:10 -0300 Subject: V4L/DVB (13154): uvcvideo: Handle garbage at the end of streaming interface descriptors At least one 5986:0241 webcam model includes vendor-specific descriptors at the end of its streaming interface descriptors. Print an information UVC_TRACE_DESCR message and try to continue parsing the descriptors rather than bailing out with an error. Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/uvc/uvc_driver.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'drivers/media/video/uvc') diff --git a/drivers/media/video/uvc/uvc_driver.c b/drivers/media/video/uvc/uvc_driver.c index ebddf006a4f..307d3a6b739 100644 --- a/drivers/media/video/uvc/uvc_driver.c +++ b/drivers/media/video/uvc/uvc_driver.c @@ -426,7 +426,8 @@ static int uvc_parse_format(struct uvc_device *dev, /* Parse the frame descriptors. Only uncompressed, MJPEG and frame * based formats have frame descriptors. */ - while (buflen > 2 && buffer[2] == ftype) { + while (buflen > 2 && buffer[1] == USB_DT_CS_INTERFACE && + buffer[2] == ftype) { frame = &format->frame[format->nframes]; if (ftype != UVC_VS_FRAME_FRAME_BASED) n = buflen > 25 ? buffer[25] : 0; @@ -503,12 +504,14 @@ static int uvc_parse_format(struct uvc_device *dev, buffer += buffer[0]; } - if (buflen > 2 && buffer[2] == UVC_VS_STILL_IMAGE_FRAME) { + if (buflen > 2 && buffer[1] == USB_DT_CS_INTERFACE && + buffer[2] == UVC_VS_STILL_IMAGE_FRAME) { buflen -= buffer[0]; buffer += buffer[0]; } - if (buflen > 2 && buffer[2] == UVC_VS_COLORFORMAT) { + if (buflen > 2 && buffer[1] == USB_DT_CS_INTERFACE && + buffer[2] == UVC_VS_COLORFORMAT) { if (buflen < 6) { uvc_trace(UVC_TRACE_DESCR, "device %d videostreaming " "interface %d COLORFORMAT error\n", @@ -749,6 +752,11 @@ static int uvc_parse_streaming(struct uvc_device *dev, buffer += buffer[0]; } + if (buflen) + uvc_trace(UVC_TRACE_DESCR, "device %d videostreaming interface " + "%d has %u bytes of trailing descriptor garbage.\n", + dev->udev->devnum, alts->desc.bInterfaceNumber, buflen); + /* Parse the alternate settings to find the maximum bandwidth. */ for (i = 0; i < intf->num_altsetting; ++i) { struct usb_host_endpoint *ep; -- cgit v1.2.3