avoid uninitialised free of ldns_res
If an invalid rdclass was passed to getrrsetbyname() then
this would execute a free on an uninitialised pointer.
OpenSSH only ever calls this with a fixed and valid rdclass.
Reported by Joshua Rogers
diff --git a/openbsd-compat/getrrsetbyname-ldns.c b/openbsd-compat/getrrsetbyname-ldns.c
index 343720f..4647b62 100644
--- a/openbsd-compat/getrrsetbyname-ldns.c
+++ b/openbsd-compat/getrrsetbyname-ldns.c
@@ -69,7 +69,7 @@
struct rrsetinfo *rrset = NULL;
struct rdatainfo *rdata;
size_t len;
- ldns_resolver *ldns_res;
+ ldns_resolver *ldns_res = NULL;
ldns_rdf *domain = NULL;
ldns_pkt *pkt = NULL;
ldns_rr_list *rrsigs = NULL, *rrdata = NULL;