gistendscan() forgot to free so->giststate.

This oversight led to a massive memory leak --- upwards of 10KB per tuple
--- during creation-time verification of an exclusion constraint based on a
GIST index.  In most other scenarios it'd just be a leak of 10KB that would
be recovered at end of query, so not too significant; though perhaps the
leak would be noticeable in a situation where a GIST index was being used
in a nestloop inner indexscan.  In any case, it's a real leak of long
standing, so patch all supported branches.  Per report from Harald Fuchs.

diff --git a/src/backend/access/gist/gistscan.c b/src/backend/access/gist/gistscan.c
index aed3e95b4e3401dc314094b4b3b5aba8877cb148..aa9f2c036bca87f78da042c71433ce5c2b8abb0d 100644 (file)
--- a/src/backend/access/gist/gistscan.c
+++ b/src/backend/access/gist/gistscan.c
@@ -135,12 +135,15 @@ gistendscan(PG_FUNCTION_ARGS)
        {
                gistfreestack(so->stack);
                if (so->giststate != NULL)
+               {
                        freeGISTstate(so->giststate);
+                       pfree(so->giststate);
+               }
                /* drop pins on buffers -- we aren't holding any locks */
                if (BufferIsValid(so->curbuf))
                        ReleaseBuffer(so->curbuf);
                MemoryContextDelete(so->tempCxt);
-               pfree(scan->opaque);
+               pfree(so);
        }
 
        PG_RETURN_VOID();