Fuzzing: Add a test for QDateTime::fromString

This patch adds a basic fuzzing test for
QDateTime::fromString.

Task-number: QTBUG-87104
Pick-to: 5.15
Change-Id: Icc51386f06f6d4d2a4495734f7fa45de80c6e065
Reviewed-by: Robert Loehning <robert.loehning@qt.io>

2 files changed, 110 insertions, 0 deletions

diff --git a/tests/libfuzzer/corelib/time/qdatetime/fromstring/fromstring.pro b/tests/libfuzzer/corelib/time/qdatetime/fromstring/fromstring.pro
new file mode 100644
index 0000000000..631fcd71e4
--- /dev/null
+++ b/tests/libfuzzer/corelib/time/qdatetime/fromstring/fromstring.pro
@@ -0,0 +1,10 @@
+QT -= gui
+CONFIG -= app_bundle
+CONFIG += console
+SOURCES += main.cpp
+FUZZ_ENGINE = $$(LIB_FUZZING_ENGINE)
+isEmpty(FUZZ_ENGINE) {
+    QMAKE_LFLAGS += -fsanitize=fuzzer
+} else {
+    LIBS += $$FUZZ_ENGINE
+}
diff --git a/tests/libfuzzer/corelib/time/qdatetime/fromstring/main.cpp b/tests/libfuzzer/corelib/time/qdatetime/fromstring/main.cpp
new file mode 100644
index 0000000000..e41301bb55
--- /dev/null
+++ b/tests/libfuzzer/corelib/time/qdatetime/fromstring/main.cpp
@@ -0,0 +1,100 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QDateTime>
+
+static const QString formats[] = {
+    QStringLiteral("h"),
+    QStringLiteral("hh"),
+    QStringLiteral("H"),
+    QStringLiteral("HH"),
+    QStringLiteral("m"),
+    QStringLiteral("mm"),
+    QStringLiteral("s"),
+    QStringLiteral("ss"),
+    QStringLiteral("z"),
+    QStringLiteral("zzz"),
+    QStringLiteral("A"),
+    QStringLiteral("t"),
+    QStringLiteral("M/d/yyyy"),
+    QStringLiteral("M/d/yyyy hh:mm"),
+    QStringLiteral("M/d/yyyy hh:mm A"),
+    QStringLiteral("M/d/yyyy, hh:mm"),
+    QStringLiteral("M/d/yyyy, hh:mm A"),
+    QStringLiteral("MMM d yyyy"),
+    QStringLiteral("MMM d yyyy hh:mm"),
+    QStringLiteral("MMM d yyyy hh:mm:ss"),
+    QStringLiteral("MMM d yyyy, hh:mm"),
+    QStringLiteral("MMM d yyyy, hh:mm:ss"),
+    QStringLiteral("MMMM d yyyy"),
+    QStringLiteral("MMMM d yyyy hh:mm"),
+    QStringLiteral("MMMM d yyyy hh:mm:ss"),
+    QStringLiteral("MMMM d yyyy, hh:mm"),
+    QStringLiteral("MMMM d yyyy, hh:mm:ss"),
+    QStringLiteral("MMMM d yyyy, hh:mm:ss t"),
+    QStringLiteral("MMM d, yyyy"),
+    QStringLiteral("MMM d, yyyy hh:mm"),
+    QStringLiteral("MMM d, yyyy hh:mm:ss"),
+    QStringLiteral("MMMM d, yyyy"),
+    QStringLiteral("MMMM d, yyyy hh:mm"),
+    QStringLiteral("MMMM d, yyyy hh:mm:ss"),
+    QStringLiteral("MMMM d, yyyy hh:mm:ss t"),
+    QStringLiteral("d MMM yyyy"),
+    QStringLiteral("d MMM yyyy hh:mm"),
+    QStringLiteral("d MMM yyyy hh:mm:ss"),
+    QStringLiteral("d MMM yyyy, hh:mm"),
+    QStringLiteral("d MMM yyyy, hh:mm:ss"),
+    QStringLiteral("d MMMM yyyy"),
+    QStringLiteral("d MMMM yyyy hh:mm"),
+    QStringLiteral("d MMMM yyyy hh:mm:ss"),
+    QStringLiteral("d MMMM yyyy, hh:mm"),
+    QStringLiteral("d MMMM yyyy, hh:mm:ss"),
+    QStringLiteral("d MMM, yyyy"),
+    QStringLiteral("d MMM, yyyy hh:mm"),
+    QStringLiteral("d MMM, yyyy hh:mm:ss"),
+    QStringLiteral("d MMMM, yyyy"),
+    QStringLiteral("d MMMM, yyyy hh:mm"),
+    QStringLiteral("d MMMM, yyyy hh:mm:ss"),
+    QStringLiteral("yyyy-MM-ddThh:mm:ss.zt"),
+};
+
+// libFuzzer entry-point for testing QDateTimeParser
+extern "C" int LLVMFuzzerTestOneInput(const char *Data, size_t Size)
+{
+    const QString userString = QString::fromUtf8(Data, Size);
+
+    QDateTime::fromString(userString, Qt::TextDate);
+    QDateTime::fromString(userString, Qt::ISODate);
+    QDateTime::fromString(userString, Qt::RFC2822Date);
+    QDateTime::fromString(userString, Qt::ISODateWithMs);
+
+    for (const auto &format : formats) {
+        QDateTime::fromString(userString, format);
+    }
+    return 0;
+}