[3.16.y-ckt stable] Patch "[media] m88ts2022: fix 32bit overflow on filter calc" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

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

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt2.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From e8df0d9fae7b2e420673a7af866cc4d5e20ec5d3 Mon Sep 17 00:00:00 2001
From: Antti Palosaari <crope at iki.fi>
Date: Thu, 21 Aug 2014 14:02:27 -0300
Subject: [media] m88ts2022: fix 32bit overflow on filter calc

commit f538e085138e519e25ae0828bd6c6e7492ce8ca4 upstream.

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 at gmail.com>
Tested-by: Nibble Max <nibble.max at gmail.com>
Signed-off-by: Antti Palosaari <crope at iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab at samsung.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 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);

--
2.1.0