From: Gert Doering <gert@...1296...>
Date: Tue,  8 Nov 2016 10:44:02 +0100
Message-Id: <1478598242-23514-1-git-send-email-gert@...1296...>
Subject: [Openvpn-devel] [PATCH] Fix potential division by zero in
	shaper_reset()
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shaper_reset() is only ever called with "bytes_per_second" set to
a non-zero value - so the whole check "is it zero? if not, use
constrain_int() to make sure it is within bounds" is not needed ->
reduce check to just constrain_int() so even if somebody would
call shaper_reset(..., 0) it would not lead to a div-by-zero.

Found by Coverity.

Signed-off-by: Gert Doering <gert@...1296...>
---
 src/openvpn/shaper.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/openvpn/shaper.h b/src/openvpn/shaper.h
index afeb9c3..fa132c4 100644
--- a/src/openvpn/shaper.h
+++ b/src/openvpn/shaper.h
@@ -75,7 +75,7 @@ bool shaper_soonest_event (struct timeval *tv, int delay);
 static inline void
 shaper_reset (struct shaper *s, int bytes_per_second)
 {
-  s->bytes_per_second = bytes_per_second ? constrain_int (bytes_per_second, SHAPER_MIN, SHAPER_MAX) : 0;
+  s->bytes_per_second = constrain_int (bytes_per_second, SHAPER_MIN, SHAPER_MAX);
 
 #ifdef SHAPER_USE_FP
   s->factor = 1000000.0 / (double)s->bytes_per_second;
-- 
2.7.3