SERVER-18111 Forbid most user operations against "system.profile"

Forbids user writes to "system.profile".  Notably, this also prevents
"system.profile" from being used as a source or target from
renameCollection.

Creation, drop, and capped conversion of "system.profile" remain
allowed.

2 files changed, 16 insertions, 3 deletions

diff --git a/src/mongo/db/ops/insert.cpp b/src/mongo/db/ops/insert.cpp
index 715895830da..38a2a478043 100644
--- a/src/mongo/db/ops/insert.cpp
+++ b/src/mongo/db/ops/insert.cpp
@@ -141,6 +141,14 @@ namespace mongo {
     }
 
     Status userAllowedWriteNS( StringData db, StringData coll ) {
+        if ( coll == "system.profile" ) {
+            return Status( ErrorCodes::BadValue,
+                           str::stream() << "cannot write to '" << db << ".system.profile'" );
+        }
+        return userAllowedCreateNS( db, coll );
+    }
+
+    Status userAllowedCreateNS( StringData db, StringData coll ) {
         // validity checking
 
         if ( db.size() == 0 )
diff --git a/src/mongo/db/ops/insert.h b/src/mongo/db/ops/insert.h
index c62985f2ec3..f55f8e80ea6 100644
--- a/src/mongo/db/ops/insert.h
+++ b/src/mongo/db/ops/insert.h
@@ -41,12 +41,17 @@ namespace mongo {
 
 
     /**
-     * check if this is a collection _any_ user can write to
-     * does NOT to permission checking, that is elsewhere
-     * for example, can't write to foo.system.bar
+     * Returns Status::OK() if this namespace is valid for user write operations.  If not, returns
+     * an error Status.
      */
     Status userAllowedWriteNS( StringData db, StringData coll );
     Status userAllowedWriteNS( StringData ns );
     Status userAllowedWriteNS( const NamespaceString& ns );
 
+    /**
+     * Returns Status::OK() if the namespace described by (db, coll) is valid for user create
+     * operations.  If not, returns an error Status.
+     */
+    Status userAllowedCreateNS( StringData db, StringData coll );
+
 }