Canvas context allocation fails because "Total canvas memory use exce…

…eds the maximum limit"

https://bugs.webkit.org/show_bug.cgi?id=195325
rdar://48609162

Reviewed by Geoff Garen.

Some pages that use a lot of transient canvas memory can hit our
artificial limits even when they are no longer referencing canvases.
This happens because we don't instantly reclaim memory when we
drop the reference, and instead have to wait for garbage collection.
This problem can also continue between page refreshes.

The limit was introduced many many releases ago when devices had
less memory, and it was more common to accidentally jetsam a page
if you used too much canvas memory. After some internal and external
discussion we've decided to remove the canvas limit and just let the page
follow the same memory restrictions as all other Web features.

This might mean more pages crash (jetsam) than break.

* LayoutTests/fast/canvas/canvas-too-large-to-draw-expected.txt: Removed.
* LayoutTests/fast/canvas/canvas-too-large-to-draw.html: Removed.
* Source/WebCore/html/CanvasBase.cpp:
(WebCore::CanvasBase::allocateImageBuffer const):
(WebCore::CanvasBase::maxActivePixelMemory): Deleted.
(WebCore::CanvasBase::setMaxPixelMemoryForTesting): Deleted.
* Source/WebCore/html/CanvasBase.h:
* Source/WebCore/html/HTMLCanvasElement.cpp:
(WebCore::HTMLCanvasElement::createContext2d):
* Source/WebCore/testing/Internals.cpp:
(WebCore::Internals::resetToConsistentState):
(WebCore::Internals::avoidIOSurfaceSizeCheckInWebProcess):
(WebCore::Internals::setMaxCanvasPixelMemory): Deleted.
* Source/WebCore/testing/Internals.idl:
* Source/WebKit/GPUProcess/graphics/RemoteRenderingBackend.cpp:
(WebKit::RemoteRenderingBackend::getPixelBufferForImageBufferWithNewMemory):

Canonical link: https://commits.webkit.org/265628@main

LayoutTests/fast/canvas/canvas-crash.html

@@ -11,10 +11,8 @@
 
 function canvastest()
 {
-    if (window.internals) {
-        window.internals.setMaxCanvasPixelMemory(16384 * 16384 * 4);
+    if (window.internals)
         window.internals.setMaxCanvasArea(13951 * 11138);
-    }
     var ctx = document.getCSSCanvasContext("2d", "canvastest", 13951, 11138);
     ctx.putImageData(ctx.getImageData(1431655766, document.getElementById("a").appendChild(document.createElement("media")).clientWidth, 4096, -1024), 128, -65535, 127, -2147483648, 2147483647, -2147483648);
 

LayoutTests/fast/canvas/canvas-skia-excessive-size.html

@@ -11,10 +11,8 @@
     if (window.testRunner)
         testRunner.dumpAsText();
 
-    if (window.internals) {
-        window.internals.setMaxCanvasPixelMemory(16384 * 16384 * 4);
+    if (window.internals)
         window.internals.setMaxCanvasArea(134217728);
-    }
 
     var canvas = document.getElementById("bigCanvas");
     var width = canvas.width;

LayoutTests/fast/canvas/large-getImageData.html

@@ -8,10 +8,8 @@
 var width = 4096;
 var height = 4097;
 
-if (window.internals) {
-    window.internals.setMaxCanvasPixelMemory(width * height * 4);
+if (window.internals)
     window.internals.setMaxCanvasArea(width * height);
-}
 
 var canvas = document.createElement('canvas');
 canvas.width = width;

LayoutTests/platform/wincairo/TestExpectations

@@ -2257,7 +2257,6 @@ webgl/2.0.0/conformance2/rendering/fs-color-type-mismatch-color-buffer-type.html
 webgl/2.0.0/conformance2/state/gl-object-get-calls.html [ Skip ] # Timeout Failure Pass
 webgl/2.0.0/conformance2/textures/misc/tex-image-with-bad-args-from-dom-elements.html [ Skip ] # Timeout
 webgl/2.0.0/conformance2/transform_feedback/transform_feedback.html [ Skip ] # Timeout and flaky
-webgl/webgl-oom-paint-document-no-crash.html [ Skip ]
 workers/bomb.html [ Skip ] # Timeout
 
 # This test is crashing on Buildbot. Skipping this test makes the subsequent test crash. Not sure which preceding test is the root cause.

Source/WebCore/html/CanvasBase.cpp

@@ -61,7 +61,6 @@ const InterpolationQuality defaultInterpolationQuality = InterpolationQuality::D
 #endif
 
 static std::optional<size_t> maxCanvasAreaForTesting;
-static std::optional<size_t> maxActivePixelMemoryForTesting;
 
 CanvasBase::CanvasBase(IntSize size, const std::optional<NoiseInjectionHashSalt>& noiseHashSalt)
     : m_size(size)
@@ -138,29 +137,6 @@ size_t CanvasBase::externalMemoryCost() const
     return m_imageBuffer->externalMemoryCost();
 }
 
-size_t CanvasBase::maxActivePixelMemory()
-{
-    if (maxActivePixelMemoryForTesting)
-        return *maxActivePixelMemoryForTesting;
-
-    static size_t maxPixelMemory;
-    static std::once_flag onceFlag;
-    std::call_once(onceFlag, [] {
-#if PLATFORM(IOS_FAMILY)
-        maxPixelMemory = ramSize() / 4;
-#else
-        maxPixelMemory = std::max(ramSize() / 4, 2151 * MB);
-#endif
-    });
-
-    return maxPixelMemory;
-}
-
-void CanvasBase::setMaxPixelMemoryForTesting(std::optional<size_t> size)
-{
-    maxActivePixelMemoryForTesting = size;
-}
-
 static inline size_t maxCanvasArea()
 {
     if (maxCanvasAreaForTesting)
@@ -349,14 +325,6 @@ RefPtr<ImageBuffer> CanvasBase::allocateImageBuffer(bool usesDisplayListDrawing,
         return nullptr;
     }
 
-    // Make sure we don't use more pixel memory than the system can support.
-    auto checkedRequestedPixelMemory = (4 * checkedArea) + activePixelMemory();
-    if (checkedRequestedPixelMemory.hasOverflowed() || checkedRequestedPixelMemory > maxActivePixelMemory()) {
-        auto message = makeString("Total canvas memory use exceeds the maximum limit (", maxActivePixelMemory() / 1024 / 1024, " MB).");
-        scriptExecutionContext()->addConsoleMessage(MessageSource::JS, MessageLevel::Warning, message);
-        return nullptr;
-    }
-
     unsigned area = checkedArea.value();
     if (!area)
         return nullptr;

Source/WebCore/html/CanvasBase.h

@@ -125,8 +125,6 @@ class CanvasBase {
     bool shouldAccelerate(const IntSize&) const;
     bool shouldAccelerate(unsigned area) const;
 
-    WEBCORE_EXPORT static size_t maxActivePixelMemory();
-    WEBCORE_EXPORT static void setMaxPixelMemoryForTesting(std::optional<size_t>);
     WEBCORE_EXPORT static void setMaxCanvasAreaForTesting(std::optional<size_t>);
 
     virtual void queueTaskKeepingObjectAlive(TaskSource, Function<void()>&&) = 0;

Source/WebCore/html/HTMLCanvasElement.cpp

@@ -347,14 +347,6 @@ CanvasRenderingContext2D* HTMLCanvasElement::createContext2d(const String& type,
     ASSERT_UNUSED(HTMLCanvasElement::is2dType(type), type);
     ASSERT(!m_context);
 
-    // Make sure we don't use more pixel memory than the system can support.
-    size_t requestedPixelMemory = 4 * width() * height();
-    if (activePixelMemory() + requestedPixelMemory > maxActivePixelMemory()) {
-        auto message = makeString("Total canvas memory use exceeds the maximum limit (", maxActivePixelMemory() / 1024 / 1024, " MB).");
-        document().addConsoleMessage(MessageSource::JS, MessageLevel::Warning, message);
-        return nullptr;
-    }
-
     m_context = CanvasRenderingContext2D::create(*this, WTFMove(settings), document().inQuirksMode());
 
 #if USE(IOSURFACE_CANVAS_BACKING_STORE)

Source/WebCore/testing/Internals.cpp

@@ -651,7 +651,6 @@ void Internals::resetToConsistentState(Page& page)
     WebCore::MediaRecorder::setCustomPrivateRecorderCreator(nullptr);
 #endif
 
-    CanvasBase::setMaxPixelMemoryForTesting(std::nullopt);
     CanvasBase::setMaxCanvasAreaForTesting(std::nullopt);
     LocalDOMWindow::overrideTransientActivationDurationForTesting(std::nullopt);
 
@@ -6507,11 +6506,6 @@ void Internals::setMockWebAuthenticationConfiguration(const MockWebAuthenticatio
 }
 #endif
 
-void Internals::setMaxCanvasPixelMemory(unsigned size)
-{
-    CanvasBase::setMaxPixelMemoryForTesting(size);
-}
-
 void Internals::setMaxCanvasArea(unsigned size)
 {
     CanvasBase::setMaxCanvasAreaForTesting(size);
@@ -7077,7 +7071,6 @@ void Internals::avoidIOSurfaceSizeCheckInWebProcess(HTMLCanvasElement& element)
         return;
     page->settings().setMaximumAccelerated2dCanvasSize(UINT_MAX);
     CanvasBase::setMaxCanvasAreaForTesting(UINT_MAX);
-    CanvasBase::setMaxPixelMemoryForTesting(UINT_MAX);
     element.setAvoidIOSurfaceSizeCheckInWebProcessForTesting();
 }
 

Source/WebCore/testing/Internals.idl

@@ -1068,7 +1068,6 @@ typedef (FetchRequest or FetchResponse) FetchObject;
 
     undefined markContextAsInsecure();
 
-    undefined setMaxCanvasPixelMemory(unsigned long size);
     undefined setMaxCanvasArea(unsigned long size);
 
     [Conditional=VIDEO] readonly attribute NowPlayingState nowPlayingState;

Source/WebKit/GPUProcess/graphics/RemoteRenderingBackend.cpp

@@ -279,7 +279,6 @@ void RemoteRenderingBackend::getPixelBufferForImageBufferWithNewMemory(Rendering
     m_getPixelBufferSharedMemory = nullptr;
     auto sharedMemory = WebKit::SharedMemory::map(WTFMove(handle), WebKit::SharedMemory::Protection::ReadWrite);
     MESSAGE_CHECK(sharedMemory, "Shared memory could not be mapped.");
-    MESSAGE_CHECK(sharedMemory->size() <= HTMLCanvasElement::maxActivePixelMemory(), "Shared memory too big.");
     m_getPixelBufferSharedMemory = WTFMove(sharedMemory);
     getPixelBufferForImageBuffer(imageBuffer, WTFMove(destinationFormat), WTFMove(srcRect), WTFMove(completionHandler));
 }