network: enable EDNS for DNS queries to support large responses

stek29 · edsiper · commit 7a524696f991 · 2025-07-14T13:32:52.000-06:00
Always set ARES_FLAG_EDNS to handle DNS responses >512 bytes. Fixes: #10588 Signed-off-by: Viktor Oreshkin <imselfish@stek29.rocks>
diff --git a/src/flb_network.c b/src/flb_network.c
@@ -1092,8 +1092,9 @@ static struct flb_dns_lookup_context *flb_net_dns_lookup_context_create(
 
     optmask = ARES_OPT_FLAGS;
 
+    opts.flags = ARES_FLAG_EDNS;
     if (dns_mode == FLB_DNS_USE_TCP) {
-        opts.flags = ARES_FLAG_USEVC;
+        opts.flags |= ARES_FLAG_USEVC;
     }
 
     *result = ares_init_options((ares_channel *) &lookup_context->ares_channel,

Original file line number	Diff line number	Diff line change
`@@ -1092,8 +1092,9 @@ static struct flb_dns_lookup_context *flb_net_dns_lookup_context_create(`
`1092`	`1092`
`1093`	`1093`	`optmask = ARES_OPT_FLAGS;`
`1094`	`1094`
	`1095`	`+ opts.flags = ARES_FLAG_EDNS;`
`1095`	`1096`	`if (dns_mode == FLB_DNS_USE_TCP) {`
`1096`		`- opts.flags = ARES_FLAG_USEVC;`
	`1097`	`+ opts.flags \|= ARES_FLAG_USEVC;`
`1097`	`1098`	`}`
`1098`	`1099`
`1099`	`1100`	`result = ares_init_options((ares_channel ) &lookup_context->ares_channel,`