[lwip-devel] Assertion fails in dns.c after PPP interface is down

[Michael Waeber]

If the ppp netif is shut down, e.g. because of a GPRS connection loss,
the DNS server address is set to the unspecified address (0.0.0.0) in
ppp.c cdns(). If a client application calls dns_gethostbyname() the
assertion in dns_send() is triggered:

>  LWIP_ASSERT("dns server has no IP address set",
!ip_addr_isany(&dns_servers[entry->server_idx]));

I think, if no DNS server is configured, dns_gethostbyname() should
succeed with "not found". Proposal patch attached.

Regards
Michael

dns.patch
Description: Text document