Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1fab46f0 authored by Oliver Endriss's avatar Oliver Endriss Committed by Mauro Carvalho Chehab
Browse files

V4L/DVB (5935): dvb_frontend: Range check of frequency and symbol rate 



Add range check of frequency and symbol rate to the FE_SET_FRONTEND ioctl.

This will also avoid a divide-by zero exception in the stv0297 driver,
if symbol rate is set to 0.

Signed-off-by: default avatarOliver Endriss <o.endriss@gmx.de>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@infradead.org>
parent 36c15f8e

drivers/media/dvb/dvb-core/dvb_frontend.c

+46 −0
Original line number Diff line number Diff line
@@ -697,6 +697,47 @@ static int dvb_frontend_start(struct dvb_frontend *fe) 
	return 0;

}



static int dvb_frontend_check_parameters(struct dvb_frontend *fe,

				struct dvb_frontend_parameters *parms)

{

	/* range check: frequency */

	if ((fe->ops.info.frequency_min &&

	     parms->frequency < fe->ops.info.frequency_min) ||

	    (fe->ops.info.frequency_max &&

	     parms->frequency > fe->ops.info.frequency_max)) {

		printk(KERN_WARNING "DVB: frontend %u frequency %u out of range (%u..%u)\n",

		       fe->dvb->num, parms->frequency,

		       fe->ops.info.frequency_min, fe->ops.info.frequency_max);

		return -EINVAL;

	}



	/* range check: symbol rate */

	if (fe->ops.info.type == FE_QPSK) {

		if ((fe->ops.info.symbol_rate_min &&

		     parms->u.qpsk.symbol_rate < fe->ops.info.symbol_rate_min) ||

		    (fe->ops.info.symbol_rate_max &&

		     parms->u.qpsk.symbol_rate > fe->ops.info.symbol_rate_max)) {

			printk(KERN_WARNING "DVB: frontend %u symbol rate %u out of range (%u..%u)\n",

			       fe->dvb->num, parms->u.qpsk.symbol_rate,

			       fe->ops.info.symbol_rate_min, fe->ops.info.symbol_rate_max);

			return -EINVAL;

		}



	} else if (fe->ops.info.type == FE_QAM) {

		if ((fe->ops.info.symbol_rate_min &&

		     parms->u.qam.symbol_rate < fe->ops.info.symbol_rate_min) ||

		    (fe->ops.info.symbol_rate_max &&

		     parms->u.qam.symbol_rate > fe->ops.info.symbol_rate_max)) {

			printk(KERN_WARNING "DVB: frontend %u symbol rate %u out of range (%u..%u)\n",

			       fe->dvb->num, parms->u.qam.symbol_rate,

			       fe->ops.info.symbol_rate_min, fe->ops.info.symbol_rate_max);

			return -EINVAL;

		}

	}



	return 0;

}



static int dvb_frontend_ioctl(struct inode *inode, struct file *file,

			unsigned int cmd, void *parg)

{
@@ -883,6 +924,11 @@ static int dvb_frontend_ioctl(struct inode *inode, struct file *file, 
	case FE_SET_FRONTEND: {

		struct dvb_frontend_tune_settings fetunesettings;



		if (dvb_frontend_check_parameters(fe, parg) < 0) {

			err = -EINVAL;

			break;

		}



		memcpy (&fepriv->parameters, parg,

			sizeof (struct dvb_frontend_parameters));