Paperclip gem is crashing the user's session in Rails -

i have found similar questions that, mine little bit different.
(paperclip 3.4.1, rails 3.2.12, ruby 1.9.3p392, using pow 0.40)

here model:

class smoke < activerecord::base    [...]    attr_accessible :latitude, :longitude, :description, :picture    validates_length_of :description, :minimum => 2, :maximum => 256, :allow_blank => true   validates_presence_of :latitude, :longitude    scope :with_picture, where("picture_file_name not null")    belongs_to :user   has_many :comments, :dependent => :destroy   has_many :smoke_reports, :dependent => :destroy    has_attached_file :picture,     :default_url => "/assets/missing/:style.jpg",     :styles => { :thumb => ["55x55", :jpg], :medium => ["500x500", :jpg], :original => ["800x800", :jpg] },     :storage => :s3,     :bucket => 'my-bucket-dev',     :path => "/:class/:style/:id.:extension",     :url => ":s3_domain_url",     :s3_credentials => {       :access_key_id => 'mys3credentials',       :secret_access_key => 'mys3credentials'   }    validates_attachment_size :picture,     :less_than => 2.megabytes    validates_attachment_content_type :picture,     :content_type => /^image\/(jpg|jpeg|pjpeg|png|x-png)$/,     :message => "invalid image type. jpg/jpeg or png accepted."    [...]  end 

where '[...]' omitted unrelated stuffs.

when validates_attachment_size or validates_attachment_content_type gives fail, error occur , session data cleaned (even login).

that's appears in application logs, check it:

started post "/smokes" 127.0.0.1 @ 2013-05-14 23:48:38 -0300 processing smokescontroller#create html warning: can't verify csrf token authenticity redirected http://weedmap.dev/login filter chain halted :deny_unlogged_users rendered or redirected completed 302 found in 9ms (activerecord: 2.4ms) 

and follow log shows when uploaded file pass trough these 2 validation methods. error appears when file not validate. check:

started post "/smokes" 127.0.0.1 @ 2013-05-14 23:33:33 -0300 processing smokescontroller#create html   parameters: {"utf8"=>"✓", "authenticity_token"=>"du+9ccvazixbbecccwr1z4izfqhxpiht6xpvcs/q3tc=", "latitude"=>"58.81374171570781", "longitude"=>"77.87109375", "picture"=>#<actiondispatch::http::uploadedfile:0x007f9f9c17e330 @original_filename="untitled-1.jpg", @content_type="image/jpeg", @headers="content-disposition: form-data; name=\"picture\"; filename=\"untitled-1.jpg\"\r\ncontent-type: image/jpeg\r\n", @tempfile=#<file:/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/rackmultipart20130514-59252-1xbz3zf>>, "description"=>"", "commit"=>"create"}   user load (0.8ms)  select "users".* "users" "users"."id" = 1 limit 1 command :: identify -format '%wx%h,%[exif:orientation]' '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an.jpg[0]' command :: convert '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an.jpg[0]' -auto-orient -resize "800x800" '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an20130514-59252-l87c43.jpg' command :: identify -format '%wx%h,%[exif:orientation]' '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an20130514-59252-l87c4320130514-59252-km9don.jpg[0]' command :: convert '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an20130514-59252-l87c4320130514-59252-km9don.jpg[0]' -auto-orient -resize "55x55" '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an20130514-59252-l87c4320130514-59252-km9don20130514-59252-4r2p3r.jpg' command :: identify -format '%wx%h,%[exif:orientation]' '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an20130514-59252-l87c4320130514-59252-km9don.jpg[0]' command :: convert '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an20130514-59252-l87c4320130514-59252-km9don.jpg[0]' -auto-orient -resize "500x500" '/var/folders/6n/2zzqcbfd1c51xz1phh8sz17h0000gn/t/untitled-120130514-59252-bu86an20130514-59252-l87c4320130514-59252-km9don20130514-59252-1byzja6.jpg'    (0.2ms)  begin   sql (1.1ms)  insert "smokes" ("created_at", "description", "latitude", "longitude", "picture_content_type", "picture_file_name", "picture_file_size", "picture_updated_at", "updated_at", "user_id") values ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10) returning "id"  [["created_at", wed, 15 may 2013 02:33:33 utc +00:00], ["description", ""], ["latitude", 58.81374171570781], ["longitude", 77.87109375], ["picture_content_type", "image/jpeg"], ["picture_file_name", "untitled-1.jpg"], ["picture_file_size", 8623], ["picture_updated_at", wed, 15 may 2013 02:33:33 utc +00:00], ["updated_at", wed, 15 may 2013 02:33:33 utc +00:00], ["user_id", nil]]   sql (0.7ms)  insert "versions" ("created_at", "event", "ip", "item_id", "item_type", "object", "whodunnit") values ($1, $2, $3, $4, $5, $6, $7) returning "id"  [["created_at", wed, 15 may 2013 02:33:33 utc +00:00], ["event", "create"], ["ip", "127.0.0.1"], ["item_id", 17], ["item_type", "smoke"], ["object", nil], ["whodunnit", #<user id: 1, name: "fernando schuindt", email: "f.schuindtcs@gmail.com", password_digest: nil, created_at: "2013-05-07 23:23:42", updated_at: "2013-05-10 06:18:41", external_provider: true, avatar_setup: 3>]] [paperclip] saving attachments. [paperclip] saving /smokes/original/17.jpg [aws s3 200 2.147466 0 retries] put_object(:acl=>:public_read,:bucket_name=>"weedsquare-dev",:content_length=>8623,:content_type=>"image/jpeg",:data=>paperclip::fileadapter: untitled-120130514-59252-bu86an20130514-59252-l87c43.jpg,:key=>"smokes/original/17.jpg")  

i pretty lost. help?

update:

here part of smokescontroller:

class smokescontroller < applicationcontroller    before_filter :deny_unlogged_users, :except => [:new, :show, :count, :refresh_profile]   before_filter :only_ajax, :only => [:new, :count, :refresh_profile]   before_filter :only_with_smoke_params, :only => [:create]    [...]    def create     @user = current_user     @smoke = smoke.new     @smoke.latitude = params[:latitude]     @smoke.longitude = params[:longitude]     @smoke.picture = params[:picture]     @smoke.description = params[:description]     if @smoke.save       @user.smokes << @smoke       redirect_to @smoke     else       render 'new'     end   end    [...]  end 

update 2:

talking on #rubyonrails@freenode.net asked me form. realized setting authenticity_token manually can see here. form_tag doing automatically. (the rails default don't knew)

anyway, here form, , still same error, same thing:

  <div id="new-smoke-form">     <%= form_tag '/smokes', :multipart => true, :method => "post" %>       <%= hidden_field_tag 'latitude', @smoke.latitude %>       <%= hidden_field_tag 'longitude', @smoke.longitude %>       <div id="new-smoke-picture">         <p>upload picture (optional):</p>         <%= file_field_tag 'picture' %>         <div class="clear">         </div>       </div>       <div id="new-smoke-description">         <p>talk it:</p>         <div id="new-smoke-remain" class="new-smoke-remain">256</div>         <%= text_area_tag 'description', nil, :class => "new-smoke-textarea", :id => "new-smoke-textarea" %>       </div>       <%= submit_tag "create", :class => "new-smoke-button" %>     <% end %>   </div> 

i getting mad.

i came across issue today, looks it's issue pow rather paperclip, related this: https://github.com/37signals/pow/issues/125

i've managed working using pow port proxy webrick instead of rack app, helps too.