Title: [278306] trunk/Source/WebCore
- Revision
- 278306
- Author
- cdu...@apple.com
- Date
- 2021-06-01 07:56:04 -0700 (Tue, 01 Jun 2021)
Log Message
Fix thread safety issues in MediaElementAudioSourceNode
https://bugs.webkit.org/show_bug.cgi?id=226475
Reviewed by Youenn Fablet.
Adopt thread safety analysis annotations in MediaElementAudioSourceNode and fix
bugs found by clang. In particular, the following issues were fixed:
- setFormat() was modifying m_muted / m_sourceNumberOfChannels / m_sourceSampleRate
on the main thread without locking, even though those data members are accessed
from the rendering thread.
- process() was accessing m_muted / m_sourceNumberOfChannels / m_sourceSampleRate
on the rendering thread *before* locking.
* Modules/webaudio/MediaElementAudioSourceNode.cpp:
(WebCore::MediaElementAudioSourceNode::setFormat):
(WebCore::MediaElementAudioSourceNode::process):
* Modules/webaudio/MediaElementAudioSourceNode.h:
Modified Paths
Diff
Modified: trunk/Source/WebCore/ChangeLog (278305 => 278306)
--- trunk/Source/WebCore/ChangeLog 2021-06-01 13:58:23 UTC (rev 278305)
+++ trunk/Source/WebCore/ChangeLog 2021-06-01 14:56:04 UTC (rev 278306)
@@ -1,3 +1,23 @@
+2021-06-01 Chris Dumez <cdu...@apple.com>
+
+ Fix thread safety issues in MediaElementAudioSourceNode
+ https://bugs.webkit.org/show_bug.cgi?id=226475
+
+ Reviewed by Youenn Fablet.
+
+ Adopt thread safety analysis annotations in MediaElementAudioSourceNode and fix
+ bugs found by clang. In particular, the following issues were fixed:
+ - setFormat() was modifying m_muted / m_sourceNumberOfChannels / m_sourceSampleRate
+ on the main thread without locking, even though those data members are accessed
+ from the rendering thread.
+ - process() was accessing m_muted / m_sourceNumberOfChannels / m_sourceSampleRate
+ on the rendering thread *before* locking.
+
+ * Modules/webaudio/MediaElementAudioSourceNode.cpp:
+ (WebCore::MediaElementAudioSourceNode::setFormat):
+ (WebCore::MediaElementAudioSourceNode::process):
+ * Modules/webaudio/MediaElementAudioSourceNode.h:
+
2021-06-01 Antti Koivisto <an...@apple.com>
Rename ComplexLineLayout to LegacyLineLayout
Modified: trunk/Source/WebCore/Modules/webaudio/MediaElementAudioSourceNode.cpp (278305 => 278306)
--- trunk/Source/WebCore/Modules/webaudio/MediaElementAudioSourceNode.cpp 2021-06-01 13:58:23 UTC (rev 278305)
+++ trunk/Source/WebCore/Modules/webaudio/MediaElementAudioSourceNode.cpp 2021-06-01 14:56:04 UTC (rev 278306)
@@ -83,6 +83,10 @@
void MediaElementAudioSourceNode::setFormat(size_t numberOfChannels, float sourceSampleRate)
{
auto protectedThis = makeRef(*this);
+
+ // Synchronize with process().
+ Locker locker { m_processLock };
+
m_muted = wouldTaintOrigin();
if (numberOfChannels != m_sourceNumberOfChannels || sourceSampleRate != m_sourceSampleRate) {
@@ -97,9 +101,6 @@
m_sourceNumberOfChannels = numberOfChannels;
m_sourceSampleRate = sourceSampleRate;
- // Synchronize with process().
- Locker locker { m_processLock };
-
if (sourceSampleRate != sampleRate()) {
double scaleFactor = sourceSampleRate / sampleRate();
m_multiChannelResampler = makeUnique<MultiChannelResampler>(scaleFactor, numberOfChannels, AudioUtilities::renderQuantumSize, std::bind(&MediaElementAudioSourceNode::provideInput, this, std::placeholders::_1, std::placeholders::_2));
@@ -150,11 +151,6 @@
{
AudioBus* outputBus = output(0)->bus();
- if (m_muted || !m_sourceNumberOfChannels || !m_sourceSampleRate) {
- outputBus->zero();
- return;
- }
-
// Use tryLock() to avoid contention in the real-time audio thread.
// If we fail to acquire the lock then the HTMLMediaElement must be in the middle of
// reconfiguring its playback engine, so we output silence in this case.
@@ -165,7 +161,8 @@
}
Locker locker { AdoptLock, m_processLock };
- if (m_sourceNumberOfChannels != outputBus->numberOfChannels()) {
+
+ if (m_muted || !m_sourceNumberOfChannels || !m_sourceSampleRate || m_sourceNumberOfChannels != outputBus->numberOfChannels()) {
outputBus->zero();
return;
}
Modified: trunk/Source/WebCore/Modules/webaudio/MediaElementAudioSourceNode.h (278305 => 278306)
--- trunk/Source/WebCore/Modules/webaudio/MediaElementAudioSourceNode.h 2021-06-01 13:58:23 UTC (rev 278305)
+++ trunk/Source/WebCore/Modules/webaudio/MediaElementAudioSourceNode.h 2021-06-01 14:56:04 UTC (rev 278306)
@@ -72,11 +72,11 @@
Ref<HTMLMediaElement> m_mediaElement;
Lock m_processLock;
- unsigned m_sourceNumberOfChannels { 0 };
- double m_sourceSampleRate { 0 };
- bool m_muted { false };
+ unsigned m_sourceNumberOfChannels WTF_GUARDED_BY_LOCK(m_processLock) { 0 };
+ double m_sourceSampleRate WTF_GUARDED_BY_LOCK(m_processLock) { 0 };
+ bool m_muted WTF_GUARDED_BY_LOCK(m_processLock) { false };
- std::unique_ptr<MultiChannelResampler> m_multiChannelResampler;
+ std::unique_ptr<MultiChannelResampler> m_multiChannelResampler WTF_GUARDED_BY_LOCK(m_processLock);
};
} // namespace WebCore
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