fixed potential invalid memory read in openpgpsdk

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@8486 b45a01b8-16f6-495d-af2f-9b41ad6348cc

openpgpsdk/src/openpgpsdk/create.c

@@ -1211,6 +1211,12 @@ ops_write_literal_data_from_file(const char *filename,
         n=read(fd,buf,1024);
         if (!n)
             break;
+        if (n == -1)
+        {
+            close(fd);
+            ops_memory_free(mem);
+            return ops_false;
+        }
         ops_memory_add(mem, &buf[0], n);
         }
     close(fd);