[ovs-dev] [PATCH v2 08/11] datapath: meter: Use 64-bit arithmetic instead of 32-bit

Greg Rose gvrose8192 at gmail.com
Wed Feb 7 15:49:58 UTC 2018


From: "Gustavo A. R. Silva" <gustavo at embeddedor.com>

Upstream commit:
    commit 5b7789e8fa8f353ad8f2c44de2385cb161b22d32
    Author: Gustavo A. R. Silva <gustavo at embeddedor.com>
    Date:   Tue Jan 30 22:55:33 2018 -0600

    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>
    Signed-off-by: David S. Miller <davem at davemloft.net>

Signed-off-by: Greg Rose <gvrose8192 at gmail.com>
---
 datapath/meter.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/datapath/meter.c b/datapath/meter.c
index d36870b..f9e8f12 100644
--- a/datapath/meter.c
+++ b/datapath/meter.c
@@ -498,7 +498,7 @@ 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)
-- 
1.8.3.1



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