From f538e085138e519e25ae0828bd6c6e7492ce8ca4 Mon Sep 17 00:00:00 2001 From: Antti Palosaari Date: Thu, 21 Aug 2014 14:02:27 -0300 Subject: [PATCH] [media] m88ts2022: fix 32bit overflow on filter calc Maximum satellite symbol rate used is 45000000Sps which overflows when multiplied by 135. As final calculation result is fraction, we could use mult_frac macro in order to keep calculation inside 32 bit number limits and prevent overflow. Original bug and fix was provided by Nibble Max. I decided to implement it differently as it is now. Reported-by: Nibble Max Tested-by: Nibble Max Cc: Signed-off-by: Antti Palosaari Signed-off-by: Mauro Carvalho Chehab --- drivers/media/tuners/m88ts2022.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/tuners/m88ts2022.c b/drivers/media/tuners/m88ts2022.c index 40c42dec721b..7a62097aa9ea 100644 --- a/drivers/media/tuners/m88ts2022.c +++ b/drivers/media/tuners/m88ts2022.c @@ -314,7 +314,7 @@ static int m88ts2022_set_params(struct dvb_frontend *fe) div_min = gdiv28 * 78 / 100; div_max = clamp_val(div_max, 0U, 63U); - f_3db_hz = c->symbol_rate * 135UL / 200UL; + f_3db_hz = mult_frac(c->symbol_rate, 135, 200); f_3db_hz += 2000000U + (frequency_offset_khz * 1000U); f_3db_hz = clamp(f_3db_hz, 7000000U, 40000000U); -- 2.20.1