[PATCH 1/8] rtl2832: fix potential integer overflow in rtl2832_set_frontend

From: Gustavo A. R. Silva
Date: Mon Jan 29 2018 - 19:52:06 EST


Cast dev->pdata->clk to u64 in order to avoid a potential integer
overflow. This variable is being used in a context that expects
an expression of type u64.

Addresses-Coverity-ID: 1271223 ("Unintentional integer overflow")
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
drivers/media/dvb-frontends/rtl2832.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index 94bf5b7..eefc301 100644
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -498,7 +498,7 @@ static int rtl2832_set_frontend(struct dvb_frontend *fe)
* RSAMP_RATIO = floor(CrystalFreqHz * 7 * pow(2, 22)
* / ConstWithBandwidthMode)
*/
- num = dev->pdata->clk * 7;
+ num = (u64)dev->pdata->clk * 7;
num *= 0x400000;
num = div_u64(num, bw_mode);
resamp_ratio = num & 0x3ffffff;
@@ -511,7 +511,7 @@ static int rtl2832_set_frontend(struct dvb_frontend *fe)
* / (CrystalFreqHz * 7))
*/
num = bw_mode << 20;
- num2 = dev->pdata->clk * 7;
+ num2 = (u64)dev->pdata->clk * 7;
num = div_u64(num, num2);
num = -num;
cfreq_off_ratio = num & 0xfffff;
--
2.7.4