CBOR support: prevent overflowing QByteArray's max allocation

QByteArray doesn't like it.

Apply the same protection to QString, which we know uses the same
backend but uses elements twice as big. That means it can contain
slightly more than half as many elements, but exact half will suffice
for our needs.

Change-Id: Iaa63461109844e978376fffd15f9d4c7a9137856
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

1 files changed, 42 insertions, 10 deletions

diff --git a/tests/auto/corelib/serialization/qcborvalue/tst_qcborvalue.cpp b/tests/auto/corelib/serialization/qcborvalue/tst_qcborvalue.cpp
index 49bb9cc144..488771d059 100644
--- a/tests/auto/corelib/serialization/qcborvalue/tst_qcborvalue.cpp
+++ b/tests/auto/corelib/serialization/qcborvalue/tst_qcborvalue.cpp
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2018 Intel Corporation.
+** Copyright (C) 2020 Intel Corporation.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the QtCore module of the Qt Toolkit.
@@ -40,6 +40,8 @@
 #include <QtCore/qcborvalue.h>
 #include <QtTest>
 
+#include <QtCore/private/qbytearray_p.h>
+
 Q_DECLARE_METATYPE(QCborKnownTags)
 Q_DECLARE_METATYPE(QCborValue)
 Q_DECLARE_METATYPE(QCborValue::EncodingOptions)
@@ -102,6 +104,8 @@ private slots:
     void fromCborStreamReaderIODevice();
     void validation_data();
     void validation();
+    void hugeDeviceValidation_data();
+    void hugeDeviceValidation();
     void recursionLimit_data();
     void recursionLimit();
     void toDiagnosticNotation_data();
@@ -1689,10 +1693,17 @@ void tst_QCborValue::fromCborStreamReaderIODevice()
     fromCbor_common(doCheck);
 }
 
+#include "../cborlargedatavalidation.cpp"
+
 void tst_QCborValue::validation_data()
 {
+    // Add QCborStreamReader-specific limitations due to use of QByteArray and
+    // QString, which are allocated by QArrayData::allocate().
+    const qsizetype MaxInvalid = std::numeric_limits<QByteArray::size_type>::max();
+    const qsizetype MinInvalid = MaxByteArraySize + 1;
     addValidationColumns();
-    addValidationData();
+    addValidationData(MinInvalid);
+    addValidationLargeData(MinInvalid, MaxInvalid);
 
     // These tests say we have arrays and maps with very large item counts.
     // They are meant to ensure we don't pre-allocate a lot of memory
@@ -1700,28 +1711,49 @@ void tst_QCborValue::validation_data()
     // elements in the stream is only 2, so we should get an unexpected EOF
     // error. QCborValue internally uses 16 bytes per element, so we get to
     // 2 GB at 2^27 elements.
-    QTest::addRow("very-large-array-no-overflow") << raw("\x9a\x07\xff\xff\xff" "\0\0");
-    QTest::addRow("very-large-array-overflow1") << raw("\x9a\x40\0\0\0" "\0\0");
+    QTest::addRow("very-large-array-no-overflow") << raw("\x9a\x07\xff\xff\xff" "\0\0") << 0 << CborErrorUnexpectedEOF;
+    QTest::addRow("very-large-array-overflow1") << raw("\x9a\x40\0\0\0" "\0\0") << 0 << CborErrorUnexpectedEOF;
 
     // this makes sure we don't accidentally clip to 32-bit: sending 2^32+2 elements
-    QTest::addRow("very-large-array-overflow2") << raw("\x9b\0\0\0\1""\0\0\0\2" "\0\0");
+    QTest::addRow("very-large-array-overflow2") << raw("\x9b\0\0\0\1""\0\0\0\2" "\0\0") << 0 << CborErrorDataTooLarge;
 }
 
 void tst_QCborValue::validation()
 {
     QFETCH(QByteArray, data);
+    QFETCH(CborError, expectedError);
+    QCborError error = { QCborError::Code(expectedError) };
 
-    QCborParserError error;
-    QCborValue decoded = QCborValue::fromCbor(data, &error);
-    QVERIFY(error.error != QCborError{});
+    QCborParserError parserError;
+    QCborValue decoded = QCborValue::fromCbor(data, &parserError);
+    QCOMPARE(parserError.error, error);
 
     if (data.startsWith('\x81')) {
         // decode without the array prefix
-        decoded = QCborValue::fromCbor(data.mid(1), &error);
-        QVERIFY(error.error != QCborError{});
+        char *ptr = const_cast<char *>(data.constData());
+        QByteArray mid = QByteArray::fromRawData(ptr + 1, data.size() - 1);
+        decoded = QCborValue::fromCbor(mid, &parserError);
+        QCOMPARE(parserError.error, error);
     }
 }
 
+void tst_QCborValue::hugeDeviceValidation_data()
+{
+    addValidationHugeDevice(MaxByteArraySize + 1, MaxStringSize + 1);
+}
+
+void tst_QCborValue::hugeDeviceValidation()
+{
+    QFETCH(QSharedPointer<QIODevice>, device);
+    QFETCH(CborError, expectedError);
+    QCborError error = { QCborError::Code(expectedError) };
+
+    device->open(QIODevice::ReadOnly | QIODevice::Unbuffered);
+    QCborStreamReader reader(device.data());
+    QCborValue decoded = QCborValue::fromCbor(reader);
+    QCOMPARE(reader.lastError(), error);
+}
+
 void tst_QCborValue::recursionLimit_data()
 {
     constexpr int RecursionAttempts = 4096;