SERVER-36239: MatchExpression parser should reject a $text query that is not operating on the top level document

(cherry picked from commit fbd991a76e141a2744b18f3f9954f345136bba6b)

2 files changed, 29 insertions, 0 deletions

diff --git a/src/mongo/db/matcher/expression_parser.cpp b/src/mongo/db/matcher/expression_parser.cpp
index 461f82fc736..3b0c14e6e84 100644
--- a/src/mongo/db/matcher/expression_parser.cpp
+++ b/src/mongo/db/matcher/expression_parser.cpp
@@ -427,6 +427,11 @@ StatusWithMatchExpression parseText(StringData name,
                                     const ExtensionsCallback* extensionsCallback,
                                     MatchExpressionParser::AllowedFeatureSet allowedFeatures,
                                     DocumentParseLevel currentLevel) {
+    if (currentLevel == DocumentParseLevel::kUserSubDocument) {
+        return {
+            Status(ErrorCodes::BadValue, "$text can only be applied to the top-level document")};
+    }
+
     if ((allowedFeatures & MatchExpressionParser::AllowedFeatures::kText) == 0u) {
         return {Status(ErrorCodes::BadValue, "$text is not allowed in this context")};
     }
diff --git a/src/mongo/db/matcher/expression_parser_test.cpp b/src/mongo/db/matcher/expression_parser_test.cpp
index d2bcd91a1b4..73011b914c6 100644
--- a/src/mongo/db/matcher/expression_parser_test.cpp
+++ b/src/mongo/db/matcher/expression_parser_test.cpp
@@ -285,6 +285,30 @@ TEST(MatchExpressionParserTest, TextParsesSuccessfullyWhenAllowed) {
             .getStatus());
 }
 
+TEST(MatchExpressionParserTest, TextFailsToParseIfNotTopLevel) {
+    auto query = fromjson("{a: {$text: {$search: 'str'}}}");
+    boost::intrusive_ptr<ExpressionContextForTest> expCtx(new ExpressionContextForTest());
+    ASSERT_NOT_OK(
+        MatchExpressionParser::parse(
+            query, expCtx, ExtensionsCallbackNoop(), MatchExpressionParser::AllowedFeatures::kText)
+            .getStatus());
+}
+
+TEST(MatchExpressionParserTest, TextWithinElemMatchFailsToParse) {
+    auto query = fromjson("{a: {$elemMatch: {$text: {$search: 'str'}}}}");
+    boost::intrusive_ptr<ExpressionContextForTest> expCtx(new ExpressionContextForTest());
+    ASSERT_NOT_OK(
+        MatchExpressionParser::parse(
+            query, expCtx, ExtensionsCallbackNoop(), MatchExpressionParser::AllowedFeatures::kText)
+            .getStatus());
+
+    query = fromjson("{a: {$elemMatch: {$elemMatch: {$text: {$search: 'str'}}}}}");
+    ASSERT_NOT_OK(
+        MatchExpressionParser::parse(
+            query, expCtx, ExtensionsCallbackNoop(), MatchExpressionParser::AllowedFeatures::kText)
+            .getStatus());
+}
+
 TEST(MatchExpressionParserTest, WhereFailsToParseWhenDisallowed) {
     auto query = fromjson("{$where: 'this.a == this.b'}");
     boost::intrusive_ptr<ExpressionContextForTest> expCtx(new ExpressionContextForTest());