pppd：memory leaks occurs when Demand-dial,please conform!

[wuleping]

pppd , demand.c , demand_conf()
When it never dials up ok, every demand-dial will apply a memory,but never free.
framemax = PPP_MRU;
framemax += PPP_HDRLEN + PPP_FCSLEN;
frame = malloc(framemax);

suggestion:
if (NULL == frame)
{
frame = malloc(framemax);
}

[paulusmack]

demand_conf() is only called once at program startup, not every time there is demand for the link, so there is no leak.