[webkit-changes] [WebKit/WebKit] 6ae064: Race condition in LibWebRTCVPXInternalVideoDecoder...

[Chris Dumez]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 6ae06410764e65994ee9d4c50e1811caa6348ddf
      https://github.com/WebKit/WebKit/commit/6ae06410764e65994ee9d4c50e1811caa6348ddf
  Author: Youenn Fablet <youenn at apple.com>
  Date:   2024-05-23 (Thu, 23 May 2024)

  Changed paths:
    A LayoutTests/http/wpt/webcodecs/copyTo-same-decoder-expected.txt
    A LayoutTests/http/wpt/webcodecs/copyTo-same-decoder.html
    M Source/WebCore/platform/libwebrtc/LibWebRTCVPXVideoDecoder.cpp

  Log Message:
  -----------
  Race condition in LibWebRTCVPXInternalVideoDecoder::pixelBufferPool leading to memory corruption
rdar://125957410

Reviewed by Chris Dumez.

Add a lock to make sure creation of the pixel buffer happens correctly.

* LayoutTests/http/wpt/webcodecs/copyTo-same-decoder-expected.txt: Added.
* LayoutTests/http/wpt/webcodecs/copyTo-same-decoder.html: Added.
* Source/WebCore/platform/libwebrtc/LibWebRTCVPXVideoDecoder.cpp:
(WebCore::LibWebRTCVPXInternalVideoDecoder::createPixelBuffer):
(WebCore::LibWebRTCVPXInternalVideoDecoder::Decoded):

Originally-landed-as: 272448.909 at safari-7618-branch (b50f1990af6e). rdar://128572002
Canonical link: https://commits.webkit.org/279196@main


  Commit: 7d0a50fadc7c19bf49866aaa29380fdc6f6738a5
      https://github.com/WebKit/WebKit/commit/7d0a50fadc7c19bf49866aaa29380fdc6f6738a5
  Author: Chris Dumez <cdumez at apple.com>
  Date:   2024-05-23 (Thu, 23 May 2024)

  Changed paths:
    M Source/WebCore/Modules/webaudio/AudioBuffer.cpp
    M Source/WebCore/Modules/webaudio/AudioBuffer.h
    M Source/WebCore/Modules/webaudio/AudioBufferSourceNode.cpp
    M Source/WebCore/Modules/webaudio/AudioBufferSourceNode.h

  Log Message:
  -----------
  [WebAudio] Use-after-free in WebCore::AudioBufferSourceNode::renderFromBuffer
https://bugs.webkit.org/show_bug.cgi?id=272607
rdar://126326144

Reviewed by Yusuke Suzuki.

The JS on the main thread can detach the AudioBuffer's channels while
it is being read by the audio rendering thread, causing use-after-frees.

In a previous fix attempt, we starting copying the AudioBuffer's channels
so that the audio thread would read a copy instead. However, the increased
memory usage resulted in increased jetsams on gaming sites.

As a temporary stop gap measure, this patch simply marks the AudioBuffer's
channels as non-detachable to prevent the issue. This is not quite spec
compliant but it addresses the security issue until we can implement the
specification correctly without causing jetsams.

* Source/WebCore/Modules/webaudio/AudioBuffer.cpp:
(WebCore::AudioBuffer::markBuffersAsNonDetachable):
* Source/WebCore/Modules/webaudio/AudioBuffer.h:
* Source/WebCore/Modules/webaudio/AudioBufferSourceNode.cpp:
(WebCore::AudioBufferSourceNode::acquireBufferContent):
(WebCore::AudioBufferSourceNode::setBufferForBindings):
(WebCore::AudioBufferSourceNode::startPlaying):
* Source/WebCore/Modules/webaudio/AudioBufferSourceNode.h:

Originally-landed-as: 272448.925 at safari-7618-branch (4201e96638f0). rdar://128572657
Canonical link: https://commits.webkit.org/279197@main


Compare: https://github.com/WebKit/WebKit/compare/14ea1c163233...7d0a50fadc7c

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