Problem with Memory Leak

Hi

I am having memory leaking problem and here is the result shown from valgrind:


==1706== 1,270 bytes in 5 blocks are still reachable in loss record 353 of 426
==1706==    at 0x4C20809: malloc (vg_replace_malloc.c:149)
==1706==    by 0x5D3F431: strdup (in /lib64/libc-2.5.so)
==1706==    by 0x109484E0: PQsendQuery (in /usr/lib64/libpq.so.5.2)


Here is my source code:

static PGresult *get_pg_result(char *sql) {


    PGresult *res=NULL;
     PGresult *final_res=NULL;
    PGconn* conn = NULL;

    int ret = 0;

    db_con_t* connection_node = get_connection();


    if (connection_node == NULL) {
        free(sql);
         return  NULL;
    }




    conn = connection_node->conn;
        if (PQstatus(conn) != CONNECTION_OK){
                PQfinish(conn);
                return NULL;
        }

            ret = PQsendQuery(conn, sql);
                if (1 != ret) {


             switch_safe_free(sql);
            release_connection(connection_node);
                       return NULL;
            }

           while ((res = PQgetResult(conn))) {


                   final_res = res;
           }







    free(sql);
    return final_res;
}