[postgis-users] GeomUnion() crashes backend?

[Hubert Fröhlich]

I tried, and it worked.
Thank you for the quick reaction.
> Ok, a simple exploit for the bug is:
> 
> 	SELECT geom_accum(NULL, NULL);
> 
> Fix is in CVS (pgis_1_0 branch).
> If you can try it that'd be nice.
> 
> --strk;
> 
> 
> On Mon, Nov 28, 2005 at 04:34:40PM +0100, strk at refractions.net wrote:
> 
>>I can reproduce the bug on Postgis-HEAD, PGSQL800.
>>accum(pgpoly) is enough, so it's not GEOS-related.
>>
>>One geometry is NULL, and that's the problem.
>>Tested on PGSQL7.3.4 everything works, so NULL
>>handling must have changed between PGSQL versions ..
>>
>>I'm checking this.
>>
>>--strk;
>>
>>
>>On Mon, Nov 28, 2005 at 03:11:41PM +0100, Hubert Fröhlich wrote:
>>
>>>Hi list,
>>>
>>>I am using Postgres on Linux boxes (SuSE 9.3 and 10.2); I use
>>>
>>>PostgreSQL 8.0.3, Geos 2.1.2, Postgis 1.0.2 combination on several HP 
>>>ProLiant ( Xeon and also Opteron) servers
>>>PostgreSQL 8.1.0, Geos 2.1.4, Postgis 1.0.4 combination on a pentium4 
>>>desktop.
>>>
>>>I am doing Postgis GeomUnion() on 3 polygons; 2 of them are relatively 
>>>large (npoints> 500), one of them is NULL (dont ask me why this is NULL!) .
>>>
>>>The dump is enclosed. (does the attachment get through the firewall? if 
>>>not, i can mail separately).
>>>
>>>When I try
>>>testpoly=# select geomunion(pgpoly) from testpoly2;
>>>server closed the connection unexpectedly
>>>        This probably means the server terminated abnormally
>>>        before or while processing the request.
>>>The connection to the server was lost. Attempting reset: Failed.
>>>
>>>I get a backend crash.
>>>
>>>What has happened?
>>>

-- 
Mit freundlichen Grüßen / With kind regards

Hubert Fröhlich

-------------------------------------------------------------------------------
Dr.-Ing. Hubert Fröhlich
Landesamt für Vermessung und Geoinformation
Alexandrastr. 4, D-80538 München, GERMANY
Tel. :+49 (0)89 / 2129 - 2980
Fax  :+49 (0)89 / 2129 - 2997
hubert dot froehlich at lvg dot bayern dot de