moc: Fix a crash with malformed input

Do not increment 'data' past the buffer in case of invalid token.

Remove the left over qDebug so we can make a test.

Task-number: QTBUG-54609
Change-Id: I8f0dd3381fbdea3f07d3c05c9a44a16d92538117
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@theqtcompany.com>

src/tools/moc/preprocessor.cpp

@@ -188,7 +188,8 @@ Symbols Preprocessor::tokenize(const QByteArray& input, int lineNum, Preprocesso
                 token = keywords[state].ident;
 
             if (token == NOTOKEN) {
-                ++data;
+                if (*data)
+                    ++data;
                 // an error really, but let's ignore this input
                 // to not confuse moc later. However in pre-processor
                 // only mode let's continue.
@@ -361,7 +362,6 @@ Symbols Preprocessor::tokenize(const QByteArray& input, int lineNum, Preprocesso
                     ++data;
                     continue;
                 }
-
                 int nextindex = pp_keywords[state].next;
                 int next = 0;
                 if (*data == pp_keywords[state].defchar)
@@ -380,7 +380,8 @@ Symbols Preprocessor::tokenize(const QByteArray& input, int lineNum, Preprocesso
 
             switch (token) {
             case NOTOKEN:
-                ++data;
+                if (*data)
+                    ++data;
                 break;
             case PP_DEFINE:
                 mode = PrepareDefine;
@@ -1251,7 +1252,6 @@ void Preprocessor::parseDefineArguments(Macro *m)
                     error("missing ')' in macro argument list");
                 break;
             } else if (!is_identifier(l.constData(), l.length())) {
-                qDebug() << l;
                 error("Unexpected character in macro argument list.");
             }
         }

tests/auto/tools/moc/tst_moc.cpp

@@ -1935,6 +1935,13 @@ void tst_Moc::warnings_data()
         << 1
         << QString("IGNORE_ALL_STDOUT")
         << QString(":2: Error: Macro invoked with too few parameters for a use of '#'");
+
+    QTest::newRow("QTBUG-54609: crash on invalid input")
+        << QByteArray::fromBase64("EAkJCQkJbGFzcyBjbGFzcyBiYWkcV2kgTUEKcGYjZGVmaW5lIE1BKFEs/4D/FoQ=")
+        << QStringList()
+        << 1
+        << QString("IGNORE_ALL_STDOUT")
+        << QString(":-1: Error: Unexpected character in macro argument list.");
 }
 
 void tst_Moc::warnings()
@@ -1950,7 +1957,7 @@ void tst_Moc::warnings()
 
 #ifdef Q_CC_MSVC
     // for some reasons, moc compiled with MSVC uses a different output format
-    QRegExp lineNumberRe(":(\\d+):");
+    QRegExp lineNumberRe(":(-?\\d+):");
     lineNumberRe.setMinimal(true);
     expectedStdErr.replace(lineNumberRe, "(\\1):");
 #endif