iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[media] m88ts2022: fix 32bit overflow on filter calc

Browse Source 
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.max@gmail.com>
Tested-by: Nibble Max <nibble.max@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
This commit is contained in:
Antti Palosaari 2014-08-21 14:02:27 -03:00 committed by Mauro Carvalho Chehab
parent de3f2e2e0a
commit f538e08513
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/media/tuners/m88ts2022.c
View File

@ -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);