[cairo-bugs] [Bug 90120] New: Image compositor can pass invalid coordinates to pixman_fill()

bugzilla-daemon at freedesktop.org bugzilla-daemon at freedesktop.org
Mon Apr 20 14:34:18 PDT 2015


            Bug ID: 90120
           Summary: Image compositor can pass invalid coordinates to
           Product: cairo
           Version: unspecified
          Hardware: Other
                OS: All
            Status: NEW
          Severity: normal
          Priority: medium
         Component: general
          Assignee: chris at chris-wilson.co.uk
          Reporter: federico at gnome.org
        QA Contact: cairo-bugs at cairographics.org

See https://bugzilla.gnome.org/show_bug.cgi?id=744391 for where this comes

Summary: librsvg gets an SVG generated through fuzz-testing, and passes big
coordinates that give problems to Cairo.  In turn, Cairo ends up passing
invalid coordinates to pixman_fill(), which does an out-of-bounds write.

Pixman doesn't validate the arguments passed to pixman_fill().

Given that Cairo's problems with big coordinates and fixed-point overflow are
Hard To Fix(tm), we can make Cairo at least responsible for not passing invalid
coordinates to pixman's low-level machinery.

The attached patch takes care of the call to pixman_fill() from this particular
code path.  I haven't gotten reports of other invalid calls to pixman_fill()
from Cairo/librsvg.

You are receiving this mail because:
You are the QA Contact for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.cairographics.org/archives/cairo-bugs/attachments/20150420/8d268518/attachment.html>

More information about the cairo-bugs mailing list