From: Ben Pfaff <blp@nicira.com>
Date: Mon, 11 Jan 2010 19:09:14 +0000 (-0800)
Subject: sflow: Avoid division by zero if sampling rate is 0.
X-Git-Tag: v0.99.1~1^2~8
X-Git-Url: http://git.onelab.eu/?a=commitdiff_plain;h=a68813c3dce6597c302c1d112f88b8020c4d2eba;p=sliver-openvswitch.git

sflow: Avoid division by zero if sampling rate is 0.

Reported by Justin Pettit.
---

diff --git a/ofproto/ofproto-sflow.c b/ofproto/ofproto-sflow.c
index 45c6c08ad..1815dd9d7 100644
--- a/ofproto/ofproto-sflow.c
+++ b/ofproto/ofproto-sflow.c
@@ -359,6 +359,13 @@ ofproto_sflow_set_options(struct ofproto_sflow *os,
     time_t now;
     int error;
 
+    if (!options->targets.n || !options->sampling_rate) {
+        /* No point in doing any work if there are no targets or nothing to
+         * sample. */
+        ofproto_sflow_clear(os);
+        return;
+    }
+
     options_changed = (!os->options
                        || !ofproto_sflow_options_equal(options, os->options));
 
@@ -371,7 +378,8 @@ ofproto_sflow_set_options(struct ofproto_sflow *os,
         error = collectors_create(&options->targets,
                                   SFL_DEFAULT_COLLECTOR_PORT, &os->collectors);
         if (os->collectors == NULL) {
-            VLOG_WARN_RL(&rl, "no configured collectors, sFlow disabled");
+            VLOG_WARN_RL(&rl, "no collectors could be initialized, "
+                         "sFlow disabled");
             ofproto_sflow_clear(os);
             return;
         }