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 39e7d32bf29173829fb94bc5933440478d3a24f7..d954581e3aa8189f15dea2edcae1dcde76fdc675 100644 (file)
--- a/src/backend/access/gist/gistscan.c
+++ b/src/backend/access/gist/gistscan.c
@@ -236,14 +236,17 @@ gistendscan(PG_FUNCTION_ARGS)
        gistfreestack(so->stack);
        gistfreestack(so->markstk);
        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);
        if (BufferIsValid(so->markbuf))
            ReleaseBuffer(so->markbuf);
        MemoryContextDelete(so->tempCxt);
-       pfree(scan->opaque);
+       pfree(so);
    }
 
    PG_RETURN_VOID();