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Subject[PATCH v3 2/8] dvb-frontends: ves1820: use 64-bit arithmetic instead of 32-bit
Add suffix ULL to constant 10 in order to give the compiler complete
information about the proper arithmetic to use. Notice that this
constant is used in a context that expects an expression of type
u64 (64 bits, unsigned).

The expression fpxin = state->config->xin * 10 is currently being
evaluated using 32-bit arithmetic.

Addresses-Coverity-ID: 200604 ("Unintentional integer overflow")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
Changes in v2:
- Update subject and changelog to better reflect the proposed code changes.
- Add suffix ULL to constant instead of casting a variable.

Changes in v3:
- Mention the specific Coverity report in the commit message.

drivers/media/dvb-frontends/ves1820.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/dvb-frontends/ves1820.c b/drivers/media/dvb-frontends/ves1820.c
index 1d89792..1760098 100644
--- a/drivers/media/dvb-frontends/ves1820.c
+++ b/drivers/media/dvb-frontends/ves1820.c
@@ -137,7 +137,7 @@ static int ves1820_set_symbolrate(struct ves1820_state *state, u32 symbolrate)
NDEC = 3;

/* yeuch! */
- fpxin = state->config->xin * 10;
+ fpxin = state->config->xin * 10ULL;
fptmp = fpxin; do_div(fptmp, 123);
if (symbolrate < fptmp)
SFIL = 1;
--
2.7.4
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