From 920ae57c147de7a53a9d47d2171be7c10d5e845c Mon Sep 17 00:00:00 2001
From: Ke Wen <kwen@nvidia.com>
Date: Tue, 16 Jul 2019 08:41:56 -0700
Subject: [PATCH] Fix #224: prevent number of IB devices from going out of
 bound

---
 src/transport/net_ib.cc | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/transport/net_ib.cc b/src/transport/net_ib.cc
index 43d8e35..c8eb6d5 100644
--- a/src/transport/net_ib.cc
+++ b/src/transport/net_ib.cc
@@ -112,13 +112,13 @@ ncclResult_t ncclIbInit(ncclDebugLogger_t logFunction) {
 
       if (ncclSuccess != wrap_ibv_get_device_list(&devices, &nIbDevs)) return ncclInternalError;
 
-      for (int d=0; d<nIbDevs; d++) {
+      for (int d=0; d<nIbDevs && ncclNIbDevs<MAX_IB_DEVS; d++) {
         struct ibv_context * context;
         if (ncclSuccess != wrap_ibv_open_device(&context, devices[d]) || context == NULL) {
           WARN("NET/IB : Unable to open device %s", devices[d]->name);
           continue;
         }
-        int found = 0;
+        int nPorts = 0;
         struct ibv_device_attr devAttr;
         memset(&devAttr, 0, sizeof(devAttr));
         if (ncclSuccess != wrap_ibv_query_device(context, &devAttr)) {
@@ -148,10 +148,10 @@ ncclResult_t ncclIbInit(ncclDebugLogger_t logFunction) {
           ncclIbDevs[ncclNIbDevs].context = context;
           strncpy(ncclIbDevs[ncclNIbDevs].devName, devices[d]->name, MAXNAMESIZE);
           ncclNIbDevs++;
-          found++;
+          nPorts++;
           pthread_create(&ncclIbAsyncThread, NULL, ncclIbAsyncThreadMain, context);
         }
-        if (found == 0 && ncclSuccess != wrap_ibv_close_device(context)) { return ncclInternalError; }
+        if (nPorts == 0 && ncclSuccess != wrap_ibv_close_device(context)) { return ncclInternalError; }
       }
       if (nIbDevs && (ncclSuccess != wrap_ibv_free_device_list(devices))) { return ncclInternalError; };
     }