SERVER-48631 Do not allow renameCollection to create collection which begins with '.'

2 files changed, 7 insertions, 2 deletions

diff --git a/jstests/core/rename.js b/jstests/core/rename.js
index 3d31a85d390..08d254bbe29 100644
--- a/jstests/core/rename.js
+++ b/jstests/core/rename.js
@@ -65,6 +65,11 @@ assert.throws(function() {
     db.jstests_rename.renameCollection({fail: "fail fail fail"});
 }, [], "renameCollection should fail when passed a garbage object");
 
+// Users should not be able to create a collection beginning with '.' through renameCollection.
+// Auth suites throw InvalidNamespace and others throw IllegalOperation error.
+assert.commandFailedWithCode(b.renameCollection(".foo"),
+                             [ErrorCodes.InvalidNamespace, ErrorCodes.IllegalOperation]);
+
 db.jstests_rename_d.drop();
 db.jstests_rename_e.drop();
 
diff --git a/src/mongo/db/ops/insert.cpp b/src/mongo/db/ops/insert.cpp
index 207df06bca0..7f27be6d6bd 100644
--- a/src/mongo/db/ops/insert.cpp
+++ b/src/mongo/db/ops/insert.cpp
@@ -184,9 +184,9 @@ Status userAllowedCreateNS(const NamespaceString& ns) {
         return Status(ErrorCodes::InvalidNamespace, str::stream() << "Invalid namespace: " << ns);
     }
 
-    if (ns.ns().find('$') != std::string::npos) {
+    if (!NamespaceString::validCollectionName(ns.coll())) {
         return Status(ErrorCodes::InvalidNamespace,
-                      str::stream() << "Cannot create a namespace containing '$': " << ns);
+                      str::stream() << "Invalid collection name: " << ns.coll());
     }
 
     if (serverGlobalParams.clusterRole == ClusterRole::ConfigServer && !ns.isOnInternalDb()) {