[postgis-devel] Possible server crash detected

[strk at refractions.net]

I've fixed the WKT parser to forbid EMPTY elements in multigeometries.
I think it makes sense. Also, if such objects are constructed with
any other mean I added some checks in the code to raise an error
rathern then crashing the backend. Crash tests welcome.

--strk;

On Tue, Apr 18, 2006 at 12:51:33PM +0200, strk at refractions.net wrote:
> Another note: MULTIPOINT(EMPTY) is interpreted as a 
> MULTIPOINT with a single, EMPTY element (which is converted
> internally to a COLLECTION, thus making it an invalid 
> representation).
> 
> I think you meant to really provide an EMPTY geometry, which
> is obtained by 'MULTIPOINT EMPTY'.
> 
> I think we should first fix the interpretation.
> 
> MULTIPOINT(EMPTY) should probably be the EMPTY geometry,
> whereas MULTIPOINT( ( EMPTY ) ) would be a multipoint
> with an EMPTY element [ possibly, *hopefully* :) unsupported ].
> 
> For a recent discussion about MULTIPOINT WKT format see:
> See: http://lists.jump-project.org/pipermail/jts-devel/2006-April/001572.html
> 
> --strk;
> 
> On Tue, Apr 18, 2006 at 12:15:25PM +0200, strk at refractions.net wrote:
> > I'm taking a look at this bug. Question really is: should we
> > allow EMPTY components in non-collection geometries ?
> > 
> > A simpler exploit for the bug is:
> > 
> > select summary('MULTIPOINT(EMPTY, 0 0)');
> > 
> > --strk;
> > 
> > On Mon, Apr 03, 2006 at 04:38:38PM +0200, Markus Schaber wrote:
> > > Hi, Strk,
> > > 
> > > strk at refractions.net wrote:
> > > > Confirmed on 1.1.2 as well.
> > > > Could you file a bug report please ?
> > > 
> > > http://postgis.refractions.net/bugs/bug.php?op=show&bugid=82&pos=20
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> 
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