From 1fab46f0decd226fcbae73b23d7f8ed478416fbb Mon Sep 17 00:00:00 2001 From: Oliver Endriss Date: Mon, 23 Jul 2007 21:00:36 -0300 Subject: [PATCH] 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: Oliver Endriss Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb/dvb-core/dvb_frontend.c | 46 +++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/drivers/media/dvb/dvb-core/dvb_frontend.c b/drivers/media/dvb/dvb-core/dvb_frontend.c index b6c7f66..384b5b8 100644 --- a/drivers/media/dvb/dvb-core/dvb_frontend.c +++ b/drivers/media/dvb/dvb-core/dvb_frontend.c @@ -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)); -- 2.7.4