ST_CurveToLine sometimes crashes server

[robe]

What steps will reproduce the problem? 1.

SELECT 'ST_CurveToLine GCSet3D: Start Testing GEOMETRYCOLLECTION';

BEGIN; SELECT ST_AsEWKT(ST_CurveToLine(foo1.the_geom))

FROM ((SELECT

ST_Collect(ST_Collect(ST_SetSRID(ST_MakePoint(i,j,m),4326),ST_SetSRID(ST_MakePolygon(ST_AddPoint(ST_AddPoint(ST_MakeLine(ST_MakePoint(i+m,j,m),ST_MakePoint(j+m,i-m,m)),ST_MakePoint(i,j,m)),ST_MakePointM(i+m,j,m))),4326)))

As the_geom

FROM generate_series(-10,50,20) As i

CROSS JOIN generate_series(50,70, 20) As j CROSS JOIN generate_series(1,2) As m GROUP BY m)) As foo1;

COMMIT; SELECT 'ST_CurveToLine GCSet3D: End Testing GEOMETRYCOLLECTION';

What is the expected output? It should do nothing and just return what I input since input contains no curves.

What do you see instead? psql:torturetest.sql:157312: server closed the connection unexpectedly

This probably means the server terminated abnormally before or while processing the request.

psql:torturetest.sql:157312: connection to server was lost

Haven't test on 1.3 but assume same issue exists

[mcayland]

Here's the preliminary backtrace:

(gdb) bt #0 0x000000000067c68a in pfree () #1 0x00007ffa773e502b in lwgeom_release (lwgeom=0xb7f420) at lwgeom.c:332 #2 0x00007ffa773df079 in LWGEOM_curve_segmentize () from /home/pg83/rel-8.3.5/lib/postgresql/postgis-1.4.so #3 0x00000000005294bd in ExecMakeFunctionResult () #4 0x0000000000527615 in ExecEvalFuncArgs () #5 0x0000000000529433 in ExecMakeFunctionResult () #6 0x00000000005273ce in ExecProject () #7 0x000000000052d1df in ExecScan () #8 0x00000000005268e8 in ExecProcNode () #9 0x0000000000524905 in ExecutorRun () #10 0x00000000005be5a0 in PortalRunSelect () #11 0x00000000005bfc09 in PortalRun () #12 0x00000000005baeac in exec_simple_query () #13 0x00000000005bc3d7 in PostgresMain () #14 0x00000000005907b2 in ServerLoop () #15 0x0000000000591494 in PostmasterMain () #16 0x0000000000546b48 in main () (gdb) frame 1 #1 0x00007ffa773e502b in lwgeom_release (lwgeom=0xb7f420) at lwgeom.c:332 332 lwfree(lwgeom→bbox); Current language: auto; currently c (gdb)

I suspect it's probably related to some geometries having bboxs and some not…

ATB,

Mark.

[mleslie]

Distilled the test case down to:

SELECT ST_CurveToLine('GEOMETRYCOLLECTION(POINT(-10 50))'::geometry);

Effects both 1.3 branch and trunk.

[mcayland]

Arrgh! I've worked out what's happening here: basically pglwgeom_serialize() alters its input geometry which should be a total no-no. The fix should be to remove this horrible piece of code from pglwgeom_serialize:

#if POSTGIS_AUTOCACHE_BBOX

if ( ! in→bbox && is_worth_caching_lwgeom_bbox(in) ) {

lwgeom_addBBOX(in);

}

#endif

and then go around the rest of the codebase fixing up any callers that require it.

ATB,

Mark.

[pramsey]

Fixed in trunk at r3807. Fixed in 1.3 at r3808.

[robe]

I renabled this test in torture script and doesn't seem to crash anymore. Haven't tested on 1.3 though. I'll test that tomorrow.

[pramsey]

<i>(No comment was entered for this change.)</i>

[pramsey]

No news is good news.

[robe]

Well I haven't tested this on 1.3.6 but crashes server on 1.3.5 production and 1.4.0 SVN (at least on Windows).

SELECT ST_CurveToLine(ST_GeomFromText('CIRCULARSTRING(4 4,4 5,4 8)'))

[robe]

Pushing this to 1.4.1 - I don't think its worthwhile holding up 1.3.6 for this and the original problem with teh original test cases works now.

[robe]

This one by the way is still an open issue. Crashes server.

[mcayland]

Another curve crasher that hasn't been resolved by Mark's patch Let's get this resolved ASAP…

[mcayland]

Fixed in 1.4 in r4271 and trunk in r4272. Colinearity in the circle points was detected, however the check was missing for the NULL pointer being returned in this case. If the points are detected as colinear, then the current behaviour is to simply append the circle points to the LINESTRING as standard points.

Again, I don't feel the need to backpatch to 1.3 due to the existing curve-related bugs that won't get fixed in that branch.

ATB,

Mark.

[robe]

Seems fine to me