SERVER-21447 reject configs with protocolversions other than 0 and 1

2 files changed, 19 insertions, 4 deletions

diff --git a/src/mongo/db/repl/replica_set_config.cpp b/src/mongo/db/repl/replica_set_config.cpp
index 106e8329473..2e83b80a000 100644
--- a/src/mongo/db/repl/replica_set_config.cpp
+++ b/src/mongo/db/repl/replica_set_config.cpp
@@ -422,10 +422,10 @@ Status ReplicaSetConfig::validate() const {
         }
     }
 
-    if (_protocolVersion < 0 || _protocolVersion > std::numeric_limits<int>::max()) {
+    if (_protocolVersion != 0 && _protocolVersion != 1) {
         return Status(ErrorCodes::BadValue,
                       str::stream() << kProtocolVersionFieldName << " field value of "
-                                    << _protocolVersion << " is out of range");
+                                    << _protocolVersion << " is not 1 or 0");
     }
 
     if (_configServer) {
diff --git a/src/mongo/db/repl/replica_set_config_test.cpp b/src/mongo/db/repl/replica_set_config_test.cpp
index 5ec17940e65..4e264f34046 100644
--- a/src/mongo/db/repl/replica_set_config_test.cpp
+++ b/src/mongo/db/repl/replica_set_config_test.cpp
@@ -89,7 +89,7 @@ TEST(ReplicaSetConfig, ParseLargeConfigAndCheckAccessors) {
                                                                    << "localhost:12345"
                                                                    << "tags" << BSON("NYC"
                                                                                      << "NY")))
-        << "protocolVersion" << 2 << "settings"
+        << "protocolVersion" << 1 << "settings"
         << BSON("getLastErrorDefaults" << BSON("w"
                                                << "majority") << "getLastErrorModes"
                                        << BSON("eastCoast" << BSON("NYC" << 1)) << "chainingAllowed"
@@ -108,7 +108,7 @@ TEST(ReplicaSetConfig, ParseLargeConfigAndCheckAccessors) {
     ASSERT_EQUALS(Seconds(5), config.getHeartbeatInterval());
     ASSERT_EQUALS(Seconds(120), config.getHeartbeatTimeoutPeriod());
     ASSERT_EQUALS(Milliseconds(10), config.getElectionTimeoutPeriod());
-    ASSERT_EQUALS(2, config.getProtocolVersion());
+    ASSERT_EQUALS(1, config.getProtocolVersion());
 }
 
 TEST(ReplicaSetConfig, MajorityCalculationThreeVotersNoArbiters) {
@@ -645,6 +645,21 @@ TEST(ReplicaSetConfig, ParseFailsWithNonExistentGetLastErrorModesConstraintTag)
     ASSERT_EQUALS(ErrorCodes::NoSuchKey, status);
 }
 
+TEST(ReplicaSetConfig, ValidateFailsWithBadProtocolVersion) {
+    ReplicaSetConfig config;
+    Status status = config.initialize(BSON("_id"
+                                           << "rs0"
+                                           << "protocolVersion" << 3 << "version" << 1 << "members"
+                                           << BSON_ARRAY(BSON("_id" << 0 << "host"
+                                                                    << "localhost:12345")
+                                                         << BSON("_id" << 1 << "host"
+                                                                       << "localhost:54321"))));
+    ASSERT_OK(status);
+
+    status = config.validate();
+    ASSERT_EQUALS(ErrorCodes::BadValue, status);
+}
+
 TEST(ReplicaSetConfig, ValidateFailsWithDuplicateMemberId) {
     ReplicaSetConfig config;
     Status status = config.initialize(BSON("_id"