Bug 90984 - Potential _cairo_bentley_ottmann_tessellate_rectangular_traps bug
Summary: Potential _cairo_bentley_ottmann_tessellate_rectangular_traps bug
Status: RESOLVED MOVED
Alias: None
Product: cairo
Classification: Unclassified
Component: general (show other bugs)
Version: unspecified
Hardware: Other All
: medium normal
Assignee: Chris Wilson
QA Contact: cairo-bugs mailing list
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2015-06-15 19:16 UTC by Tom Klein
Modified: 2018-08-25 13:39 UTC (History)
1 user (show)

See Also:
i915 platform:
i915 features:


Attachments
_cairo_bentley_ottmann_tessellate_rectangular_traps patch (912 bytes, text/plain)
2015-06-15 19:16 UTC, Tom Klein
Details

Description Tom Klein 2015-06-15 19:16:26 UTC
Created attachment 116523 [details]
_cairo_bentley_ottmann_tessellate_rectangular_traps patch

This is being reported with reference to firefox bug 853889: https://bugzilla.mozilla.org/show_bug.cgi?id=853889

As explained in that bug, using firefox's old version of cairo, there's a bug related to _cairo_bentley_ottmann_tessellate_rectangular_traps:
if more than one trap is passed in then it's guaranteed that the returned traps will have their left edge to the left of their right edge, but if only one trap is passed in then the function always returns without doing anything.

I don't think that bug is reproducible with current cairo code (all current calls to _cairo_bentley_ottmann_tessellate_rectangular_traps appear to be guarded by traps.has_intersections checks, which I think implies more than one trap), but it seems like it's still a potential hole for a future bug, and I see a similar hole in _cairo_bentley_ottmann_tessellate_boxes has been fixed already.
Comment 1 Chris Wilson 2015-06-16 09:50:24 UTC
Looks fine.
Comment 2 GitLab Migration User 2018-08-25 13:39:10 UTC
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/cairo/cairo/issues/118.


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