Fix UB in webp decode and memory leak in encoder

Ensure the ICC block is aligned before parsing and clear the writer
after we have initialized it.

Fixes: QTBUG-84267
Change-Id: I7e16ee7663dbe404b4819769deab7d9c9b6c8f20
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>
(cherry picked from commit b761ff58d6)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
This commit is contained in:
Allan Sandfeld Jensen 2020-05-18 13:51:09 +02:00 committed by Qt Cherry-pick Bot
parent ec15f82b67
commit 1a790ba615
1 changed files with 7 additions and 2 deletions

View File

@ -167,8 +167,11 @@ bool QWebpHandler::read(QImage *image)
// Read global meta-data chunks first // Read global meta-data chunks first
WebPChunkIterator metaDataIter; WebPChunkIterator metaDataIter;
if ((m_formatFlags & ICCP_FLAG) && WebPDemuxGetChunk(m_demuxer, "ICCP", 1, &metaDataIter)) { if ((m_formatFlags & ICCP_FLAG) && WebPDemuxGetChunk(m_demuxer, "ICCP", 1, &metaDataIter)) {
const QByteArray iccProfile = QByteArray::fromRawData(reinterpret_cast<const char *>(metaDataIter.chunk.bytes), QByteArray iccProfile = QByteArray::fromRawData(reinterpret_cast<const char *>(metaDataIter.chunk.bytes),
metaDataIter.chunk.size); metaDataIter.chunk.size);
// Ensure the profile is 4-byte aligned.
if (reinterpret_cast<qintptr>(iccProfile.constData()) & 0x3)
iccProfile.detach();
m_colorSpace = QColorSpace::fromIccProfile(iccProfile); m_colorSpace = QColorSpace::fromIccProfile(iccProfile);
// ### consider parsing EXIF and/or XMP metadata too. // ### consider parsing EXIF and/or XMP metadata too.
WebPDemuxReleaseChunkIterator(&metaDataIter); WebPDemuxReleaseChunkIterator(&metaDataIter);
@ -288,6 +291,7 @@ bool QWebpHandler::write(const QImage &image)
if (!WebPEncode(&config, &picture)) { if (!WebPEncode(&config, &picture)) {
qWarning() << "failed to encode webp picture, error code: " << picture.error_code; qWarning() << "failed to encode webp picture, error code: " << picture.error_code;
WebPPictureFree(&picture); WebPPictureFree(&picture);
WebPMemoryWriterClear(&writer);
return false; return false;
} }
@ -336,6 +340,7 @@ bool QWebpHandler::write(const QImage &image)
static_cast<size_t>(device()->write(reinterpret_cast<const char *>(writer.mem), writer.size))); static_cast<size_t>(device()->write(reinterpret_cast<const char *>(writer.mem), writer.size)));
} }
WebPPictureFree(&picture); WebPPictureFree(&picture);
WebPMemoryWriterClear(&writer);
return res; return res;
} }