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 <nibble....@gmail.com>
Cc: <sta...@kernel.org>
Signed-off-by: Antti Palosaari <cr...@iki.fi>
---
 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 40c42de..7a62097 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);
 
-- 
http://palosaari.fi/

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