Bug 206055

Summary: Decoding an SVG off the main thread causes a crash
Product: WebKit Reporter: Chris Lord <clord>
Component: SVGAssignee: Chris Lord <clord>
Status: RESOLVED FIXED    
Severity: Normal CC: ap, cdumez, changseok, darin, dino, esprehn+autocc, ews-watchlist, fmalita, gyuyoung.kim, pdr, sabouhallawa, schenney, sergio, simon.fraser, webkit-bug-importer, zimmermann
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 183720    
Attachments:
Description Flags
Patch
none
Patch none

Chris Lord
Reported 2020-01-10 02:26:14 PST
If you decode an SVG off the main thread via ImageBitmap, this results in a crash. You can test this by enabling offscreen-canvas and running either of these two tests: imported/w3c/web-platform-tests/offscreen-canvas/drawing-images-to-the-canvas/2d.drawImage.svg.worker.html imported/w3c/web-platform-tests/offscreen-canvas/drawing-images-to-the-canvas/2d.drawImage.zerosource.image.worker.html
Attachments
Patch (6.74 KB, patch)
2021-04-30 05:09 PDT, Chris Lord 		no flags
DetailsFormatted DiffDiff
Patch (6.99 KB, patch)
2021-05-03 01:33 PDT, Chris Lord 		no flags
DetailsFormatted DiffDiff
Show Obsolete (1) View All Add attachment proposed patch, testcase, etc.
Simon Fraser (smfr)
Comment 1 2020-01-13 11:05:20 PST
None of the SVG code is thread safe. You'll need to bounce to the main thread for SVG.
Chris Lord
Comment 2 2021-04-30 05:09:54 PDT
Created attachment 427409 [details] Patch
Chris Lord
Comment 3 2021-04-30 06:40:10 PDT
Comment on attachment 427409 [details] Patch ImageBitmap obviously doesn't need an actual SVG document, it was only using Image to get the bitmap data. Instead, use BitmapImage directly and bypass the SVG and PDF document image loaders.
Darin Adler
Comment 4 2021-04-30 10:33:11 PDT
Comment on attachment 427409 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=427409&action=review > Source/WebCore/html/ImageBitmap.cpp:739 > + auto image = BitmapImage::create(&observer.get()); The better idiom here is observer.ptr(). > Source/WebCore/html/ImageBitmap.cpp:760 > + bitmapData->context().drawImage(image.get(), destRect, sourceRectangle.releaseReturnValue(), { interpolationQualityForResizeQuality(options.resizeQuality), imageOrientationForOrientation(options.imageOrientation) }); Not sure we need ".get()" here. Ref typically converts itself to a reference when passing it as an argument. > Source/WebCore/svg/graphics/SVGImage.cpp:83 > + ASSERT(isMainThread()); Consider also having this assertion in Image::create itself? The assertion without a comment seems a little mysterious; not that I’d want a long comment.
Chris Lord
Comment 5 2021-05-03 01:33:46 PDT
Created attachment 427544 [details] Patch
EWS
Comment 6 2021-05-03 02:29:58 PDT
Committed r276895 (237241@main): <https://commits.webkit.org/237241@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 427544 [details].
Radar WebKit Bug Importer
Comment 7 2021-05-03 02:30:18 PDT
<rdar://problem/77448836>
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