[ovs-dev] [PATCH] openvswitch: meter: Use 64-bit arithmetic instead of 32-bit

Gustavo A. R. Silva gustavo at embeddedor.com
Wed Jan 31 04:55:33 UTC 2018


Add suffix LL to constant 1000 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 long long int (64 bits, signed).

The expression (band->burst_size + band->rate) * 1000 is currently
being evaluated using 32-bit arithmetic.

Addresses-Coverity-ID: 1461563 ("Unintentional integer overflow")
Signed-off-by: Gustavo A. R. Silva <gustavo at embeddedor.com>
---
 net/openvswitch/meter.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/openvswitch/meter.c b/net/openvswitch/meter.c
index 3fbfc78..04b9428 100644
--- a/net/openvswitch/meter.c
+++ b/net/openvswitch/meter.c
@@ -488,7 +488,7 @@ bool ovs_meter_execute(struct datapath *dp, struct sk_buff *skb,
 		long long int max_bucket_size;
 
 		band = &meter->bands[i];
-		max_bucket_size = (band->burst_size + band->rate) * 1000;
+		max_bucket_size = (band->burst_size + band->rate) * 1000LL;
 
 		band->bucket += delta_ms * band->rate;
 		if (band->bucket > max_bucket_size)
-- 
2.7.4



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