ldns_rdf2buffer_str_wks never return when WKS record includes port number 65528 or higher

NLnetLabs / ldns

LDNS is a DNS library that facilitates DNS tool programming

https://nlnetlabs.nl/ldns

BSD 3-Clause "New" or "Revised" License

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ldns_rdf2buffer_str_wks never return when WKS record includes port number 65528 or higher #95

Closed yuuki-w closed 4 years ago

yuuki-w commented 4 years ago

When a WKS record has services which port number is over 65528, ldns_rdf2buffer_str_wks never return.

In host2str.c:841 (in 1.7.1)

 822     uint16_t current_service;
// ...
 840     for (current_service = 0;
 841          current_service < (ldns_rdf_size(rdf)-1)*8; current_service++) {

In this case, (ldns_rdf_size(rdf)-1)* 8 is 65536 but the variable current_service is uint16_t so overflows after checking port 65535, the condition never become false.

wtoorop commented 4 years ago

Perfect. Thanks!

wtoorop commented 4 years ago

I mean good catch :). The perfect is for PR #96