[lwip-devel] Use of LWIP_ERROR in dhcp.c

[Craig McQueen]

I see in dhcp.c, there is use of LWIP_ERROR when checking values in the DHCP 
message from the server. Eg in dhcp_parse_reply():

    LWIP_ERROR("len == 4", len == 4, return ERR_VAL;);

But LWIP_ERROR() is equivalent to an assert(), and will cause an infinite loop 
(and probably watchdog reset). So LWIP_ERROR() isn't suitable to use when 
parsing protocol data, is it? Otherwise, an attacker could cause a system reset 
by sending malformed data to the device.

-- 
Craig McQueen