Bug 38684

Summary: Incorrect RenderPath object size when large coordinate values encountered
Product: WebKit Reporter: W. James MacLean <wjmaclean>
Component: SVGAssignee: Nobody <webkit-unassigned>
Status: RESOLVED INVALID    
Severity: Normal CC: krit, simon.fraser, zimmermann
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: All   
OS: OS X 10.5   
Bug Depends on:    
Bug Blocks: 25645    
Attachments:
Description Flags
SVG File with large coordinate values none

W. James MacLean
Reported 2010-05-06 13:32:05 PDT
Steps to Reproduce: Render the attached SVG file (mask-excessive-malloc.svg, from the existing layout tests directory) Actual output: dumping the render tree gives layer at (0,0) size 800x600 RenderView at (0,0) size 800x600 layer at (0,0) size 800x600 RenderSVGRoot {svg} at (0,0) size 800x600 RenderSVGResourceMasker {mask} [id="mask"] [maskUnits=objectBoundingBox] [maskContentUnits=userSpaceOnUse] RenderPath {rect} at (0,0) size 0x0 [fill={[type=SOLID] [color=#FFFFFF]}] [data="M0.00,0.00 L2147483648.00,0.00 L2147483648.00,2147483648.00 L0.00,2147483648.00 Z"] RenderPath {path} at (200,200) size 100x200 [fill={[type=SOLID] [color=#0000FF]}] [data="M200.00,200.00 L300.00,200.00 L300.00,400.00 L200.00,400.00 Z"] [masker="mask"] RenderSVGResourceMasker {mask} at (190,180) size 214748364800.00x429496729600.00 Expected output: the render tree should look like (note size of first RenderPath object): layer at (0,0) size 800x600 RenderView at (0,0) size 800x600 layer at (0,0) size 800x600 RenderSVGRoot {svg} at (0,0) size 800x600 RenderSVGResourceMasker {mask} [id="mask"] [maskUnits=objectBoundingBox] [maskContentUnits=userSpaceOnUse] RenderPath {rect} at (0,0) size 800x600 [fill={[type=SOLID] [color=#FFFFFF]}] [data="M0.00,0.00 L2147483648.00,0.00 L2147483648.00,2147483648.00 L0.00,2147483648.00 Z"] RenderPath {path} at (200,200) size 100x200 [fill={[type=SOLID] [color=#0000FF]}] [data="M200.00,200.00 L300.00,200.00 L300.00,400.00 L200.00,400.00 Z"] [masker="mask"] RenderSVGResourceMasker {mas Chromium 5.0.395.0 (46220) Additional information: The underlying cause appears to be an unsafe float-> int conversion in FloatRect::enclosingIntRect, where static_cast<int> is used on a float outside the range representable by int.
Attachments
SVG File with large coordinate values (289 bytes, image/svg+xml)
2010-05-06 13:33 PDT, W. James MacLean 		no flags
Details
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W. James MacLean
Comment 1 2010-05-06 13:33:16 PDT
Created attachment 55290 [details] SVG File with large coordinate values
Alexey Proskuryakov
Comment 2 2010-05-07 15:15:34 PDT
*** Bug 38680 has been marked as a duplicate of this bug. ***
Alexey Proskuryakov
Comment 3 2010-05-07 15:16:18 PDT
An explanation of why this is wrong from duplicate: If you modify mask-excessive-malloc.svg so the rect has dimensions in the range of int, and dump the results render tree, you will find the size of the RenderPath (line 6) is 800x600, not 0x0. I.e. it clips to the size of the view port. If you fix the float -> int conversions so that values greater than the max int 2147483647 are clipped to 2147483647 (which is one reasonable approach), then the size will be computed as 800x600. The 0x0 size seems to occur when very large positive floats get erroneously converted to -2147483648, which gets clipped to 0 for lengths such as height and width.
Nikolas Zimmermann
Comment 4 2010-07-09 07:25:31 PDT
Changed component to SVG, so it shows up in my all-svg-bugs search.
Dirk Schulze
Comment 5 2016-10-12 05:43:45 PDT
We changed that a long time ago and this particular test passes and we actually do have a test for it in the repo. However, there might be still problems with huge values. Instead you should use viewBox, transform or similar ways to upscale.
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