SERVER-42312 disallow validate cmd during rollback and recovering states

jstests/noPassthrough/standalone_replication_recovery.js

@@ -79,6 +79,9 @@ node = rst.start(node, {noReplSet: true, setParameter: {logComponentVerbosity: l
 reconnect(node);
 assertDocsInColl(node, []);
 
+// Test that we can run the validate command on a standalone.
+assert.commandWorked(node.getDB(dbName).runCommand({"validate": collName}));
+
 jsTestLog("Test that on restart with the flag set we play recovery.");
 node = rst.restart(node, {
     noReplSet: true,
@@ -87,6 +90,9 @@ node = rst.restart(node, {
 reconnect(node);
 assertDocsInColl(node, [3, 4, 5]);
 
+// Test that we can run the validate command on a standalone that recovered.
+assert.commandWorked(node.getDB(dbName).runCommand({"validate": collName}));
+
 jsTestLog("Test that we go into read-only mode.");
 assert.commandFailedWithCode(getColl(node).insert({_id: 1}), ErrorCodes.IllegalOperation);
 

jstests/replsets/validate_fails_during_rollback.js

@@ -0,0 +1,38 @@
+/*
+ * This test makes sure the 'validate' command fails correctly during rollback.
+ */
+(function() {
+"use strict";
+
+load("jstests/replsets/libs/rollback_test.js");
+
+const dbName = "test";
+const collName = "coll";
+
+// Set up Rollback Test.
+let rollbackTest = new RollbackTest();
+
+let rollbackNode = rollbackTest.transitionToRollbackOperations();
+
+assert.commandWorked(rollbackNode.adminCommand(
+    {configureFailPoint: "rollbackHangAfterTransitionToRollback", mode: "alwaysOn"}));
+
+// Start rollback.
+rollbackTest.transitionToSyncSourceOperationsBeforeRollback();
+rollbackTest.transitionToSyncSourceOperationsDuringRollback();
+
+// Wait for rollback to hang.
+checkLog.contains(rollbackNode, "rollbackHangAfterTransitionToRollback fail point enabled.");
+
+// Try to run the validate command on the rollback node. This should fail with a NotMaster error.
+assert.commandFailedWithCode(rollbackNode.getDB(dbName).runCommand({"validate": collName}),
+                             ErrorCodes.NotMasterOrSecondary);
+
+assert.commandWorked(rollbackNode.adminCommand(
+    {configureFailPoint: "rollbackHangAfterTransitionToRollback", mode: "off"}));
+
+rollbackTest.transitionToSteadyStateOperations();
+
+// Check the replica set.
+rollbackTest.stop();
+}());

src/mongo/db/catalog/collection_validation.cpp

@@ -397,6 +397,12 @@ Status validate(OperationContext* opCtx,
     // constructor fail the cmd, as opposed to returning OK with valid:false.
     ValidateState validateState(opCtx, nss, background, fullValidate);
 
+    const auto replCoord = repl::ReplicationCoordinator::get(opCtx);
+    // Check whether we are allowed to read from this node after acquiring our locks. If we are
+    // in a state where we cannot read, we should not run validate.
+    uassertStatusOK(replCoord->checkCanServeReadsFor(
+        opCtx, nss, ReadPreferenceSetting::get(opCtx).canRunOnSecondary()));
+
     try {
         std::map<std::string, int64_t> numIndexKeysPerIndex;
         ValidateResultsMap indexNsResultsMap;

src/mongo/db/commands/validate.cpp

@@ -97,6 +97,10 @@ public:
         return true;
     }
 
+    bool maintenanceOk() const override {
+        return false;
+    }
+
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) const {