Re: crash in hangul module + patch

[Owen Taylor <otaylor redhat com>]

On Thu, 2004-02-19 at 15:23, Radek Doulík wrote:
> On Thu, 2004-02-19 at 08:58 -0500, Owen Taylor wrote:
> 
> > On Thu, 2004-02-19 at 06:21, Radek Doulík wrote:
> > > Hi,
> > > 
> > > I am experiencing crashes in pango when rendering attached file (text.
> > > utf8). The crash happens in hangul module, where it access memory
> > > outside array (__jamo_to_ksc5601) boundaries.
> > > 
> > > While the attached patch checks the boundaries and avoid the crash, it
> > > probably doesn't fix the whole problem. I didn't look deeper into it,
> > > but it seems that pango_itemize should probably make 2 items instead of
> > > one with hangul shaper.
> > 
> > http://bugzilla.gnome.org/show_bug.cgi?id=129741
> > 
> > In general all shapers need to be handle any characters fed to them, at
> > least in a simplistic fashion because there is an actual need to feed
> > neutral characters such as white space, zero width marks, etc to the
> > shaper handling the adjacent text.
> > 
> > I'd really love it if someone could take a look at this bug and figure
> > out the right fix.
> 
> okie, why not to use my fix meanwhile, so it doesn't crash anymore? it
> may print some warning if necessary.

You patch will cause more subtle crashes by violating the constraint
that every input glyph must end up as part of a cluster; I think
this one is best solved right, which probably isn't even very hard.

Regards,
						Owen