The header contains invalid characters

Edit: Found the problem! https://github.com/koajs/generic-session/issues/96#issuecomment-234743407

When running:

this.session.count = 12

This exception gets thrown:

  koa-generic-session set error: The header content contains invalid characters
      at ServerResponse.OutgoingMessage.setHeader (_http_outgoing.js:351:13)
      at Cookies.set (..project\node_modules\cookies\lib\cookies.js:100:13)
      at Object.options.sessionIdStore.set (..project\node_modules\koa-generic-session\lib\session.js:93:20)
      at Object.saveNow (..project\node_modules\koa-generic-session\lib\session.js:283:26)
      at next (native)
      at onFulfilled (..project\node_modules\co\index.js:65:19)
      at process._tickCallback (node.js:369:9)

These are the modules that I used:

koa v1.2.0
koa-generic-session v1.11.1
koa-router v5.4.0

Can be reproduced with the following application:

'use strict'

const koa = require('koa')

const router  = require('koa-router')()
const session = require('koa-generic-session')

const app = koa()

app.keys = ['key']
app.use(session())

router.get('/', function* () {
    this.session.count = 12
    this.body = 'test'
});

app.use(router.routes())

app.listen(3000)
console.log('listening on port 3000')

[nallown]

Looks like that it was a issue with the newer versions of node. It works fine with version 4.2.6 of node.

It might be worth checking out this change https://github.com/nodejs/node/commit/cf2b714b02 to add support for newer versions of node.

Edit: As a temporary solution you can run the node application with --security-revert=CVE-2016-2216

[nallown]

Updating koa to version 1.2.1 and koa-generic-session to version 1.11.3 fixed it.