> The problematic bit is, I think, 's' in babel_handle_update can be NULL > because nothing ensures the babel_source for a particular neighbour > actually exists here:
s will be passed to babel_is_feasible, which returns true if s is null. Later on, s is only used if feasible is false, in which case it cannot be null. See RFC 8966 Section 3.5.1: a route advertisement carrying the quintuple (prefix, plen, router-id, seqno, metric) is feasible if one of the following conditions holds: • ... • no entry exists in the source table indexed by (prefix, plen, router-id); • ... I agree that the code is a little too subtle for comfort. > Perhaps find should just be replaced by babel_get_source here? babel_get_source sets the seqno to an arbitrary value (0), so it should only be used if it is immediately followed by an assignment to s->seqno. A better API would be to pass the seqno to babel_get_source. (I haven't looked at it in detail, but the code in babel_send_update_ looks incorrect to me, by the way: it's comparing seqnos as integers, where it should be doing comparisons modulo 2¹⁶, as defined in Section 3.2.1. Toke?) -- Juliusz