sending values from javascript into ruby injection

index.html.erb

<input type="button" onclick="myfunction()" value="NEWEdit" />

<script language="javascript" type="text/javascript">

$(function() {
  $(document).on('click', '#edit', function() {
    $('#he').text($('#posts').data('count'));

  });
});

</script>

<div id="posts" data-count="<%= params[:count] %>">
<h2 id='he'></h2>
<input type="button" id="edit" value="NEWEdit" />

post_controller.rb

class PostsController < ApplicationController
  # GET /posts
  # GET /posts.json
  def index
    @posts = Post.all
    @val=params[:count].to_i

    respond_to do |format|
      format.html # index.html.erb
      format.json { render :json => @posts }
    end
  end