http: fix rawHeaders exceeding maxHeadersCount limit

Fixes: #61284
PR-URL: #61285
Reviewed-By: Tim Perry <pimterry@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

Author: Meltedd

lib/_http_common.js

@@ -59,9 +59,11 @@ const MAX_HEADER_PAIRS = 2000;
 // called to process trailing HTTP headers.
 functionparserOnHeaders(headers,url){
 // Once we exceeded headers limit - stop collecting them
-if(this.maxHeaderPairs<=0||
-this._headers.length<this.maxHeaderPairs){
+constcapacity=this.maxHeaderPairs-this._headers.length;
+if(this.maxHeaderPairs<=0||capacity>=headers.length){
 this._headers.push(...headers);
+}elseif(capacity>0){
+this._headers.push(...headers.slice(0,capacity));
 }
 this._url+=url;
 }

test/parallel/test-http-rawheaders-limit.js

@@ -0,0 +1,26 @@
+'use strict';
+constcommon=require('../common');
+constassert=require('assert');
+consthttp=require('http');
+constnet=require('net');
+
+constserver=http.createServer(common.mustCall((req,res)=>{
+constlimit=server.maxHeadersCount*2;
+assert.ok(req.rawHeaders.length<=limit,
+`rawHeaders.length (${req.rawHeaders.length}) exceeds limit (${limit})`);
+res.end();
+server.close();
+}));
+
+server.maxHeadersCount=50;
+
+server.listen(0,common.mustCall(()=>{
+constport=server.address().port;
+constheaders=Array.from({length: 65},(_,i)=>`X-${i}:v`).join('\r\n');
+constreq=`GET / HTTP/1.1\r\nHost: localhost\r\n${headers}\r\n\r\n`;
+
+net.createConnection(port,'localhost',function(){
+this.write(req);
+this.once('data',()=>this.end());
+});
+}));