diff --git a/src/discuss.ml b/src/discuss.ml
index 42b1d47..9ad3bc1 100644
--- a/src/discuss.ml
+++ b/src/discuss.ml
@@ -130,7 +130,4 @@ let post request =
         | Ok () -> pp_discussion (request, user_id, comrade_id)
         | Error e -> Utils.render e request
       end
-      | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-      | `Expired _ | `Many_tokens _ | `Missing_token _ | `Invalid_token _
-      | `Wrong_session _ | `Wrong_content_type ->
-        Dream.empty `Bad_Request )
+      | form -> Utils.handle_invalid_form form )
diff --git a/src/permap.ml b/src/permap.ml
index 254f36a..9051edd 100644
--- a/src/permap.ml
+++ b/src/permap.ml
@@ -30,10 +30,7 @@ let register_post request =
           (User.login ~login:nick ~password request)
       in
       render res request )
-  | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-  | `Many_tokens _ | `Missing_token _ | `Invalid_token _ | `Wrong_session _
-  | `Expired _ | `Wrong_content_type ->
-    Dream.empty `Bad_Request
+  | form -> Utils.handle_invalid_form form
 
 let login_get request = render (Login.f request) request
 
@@ -51,10 +48,7 @@ let login_post request =
       Dream.respond ~status:`See_Other
         ~headers:[ ("Location", url) ]
         "Logged in: Happy geo-posting!" )
-  | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-  | `Many_tokens _ | `Missing_token _ | `Invalid_token _ | `Wrong_session _
-  | `Expired _ | `Wrong_content_type ->
-    Dream.empty `Bad_Request
+  | form -> Utils.handle_invalid_form form
 
 let admin_get request =
   match Dream.session "user_id" request with
@@ -101,10 +95,7 @@ let admin_post request =
             Dream.respond ~status:`See_Other
               ~headers:[ ("Location", "/admin") ]
               "" )
-        | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-        | `Expired _ | `Many_tokens _ | `Missing_token _ | `Invalid_token _
-        | `Wrong_session _ | `Wrong_content_type ->
-          Dream.empty `Bad_Request )
+        | form -> Utils.handle_invalid_form form )
 
 let catalog request =
   let catalog_content =
@@ -132,10 +123,7 @@ let delete_post request =
           Dream.respond ~status:`See_Other
             ~headers:[ ("Location", "/") ]
             "Your post was deleted!" )
-      | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-      | `Expired _ | `Many_tokens _ | `Missing_token _ | `Invalid_token _
-      | `Wrong_session _ | `Wrong_content_type ->
-        Dream.empty `Bad_Request )
+      | form -> Utils.handle_invalid_form form )
 
 let report_get request =
   let post_id = Dream.param request "post_id" in
@@ -153,10 +141,7 @@ let report_post request =
         let post_id = Dream.param request "post_id" in
         let* () = Babillard.report ~user_id ~reason post_id in
         Ok "The post was reported!"
-      | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-      | `Expired _ | `Many_tokens _ | `Missing_token _ | `Invalid_token _
-      | `Wrong_session _ | `Wrong_content_type ->
-        Dream.empty `Bad_Request )
+      | form -> Utils.handle_invalid_form form )
 
 let user request =
   render (Result.fold ~ok:Fun.id ~error:Fun.id (User.list ())) request
@@ -205,10 +190,7 @@ let account_post request =
           let* () = User.update_password password user_id in
           Ok "Your password was updated!"
         else Error "Password confirmation does not match"
-      | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-      | `Many_tokens _ | `Missing_token _ | `Invalid_token _ | `Wrong_session _
-      | `Expired _ | `Wrong_content_type ->
-        Dream.empty `Bad_Request )
+      | form -> Utils.handle_invalid_form form )
 
 let profile_get request =
   Utils.logged_in_or_redirect request (fun user_id ->
@@ -246,6 +228,7 @@ let profile_post request =
       | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
       | `Many_tokens _ | `Missing_token _ | `Invalid_token _ | `Wrong_session _
       | `Expired _ | `Wrong_content_type -> (
+        (* TODO: why is this here ?! *)
         match%lwt Dream.multipart request with
         | `Ok [ ("file", file) ] -> (
           match User.upload_avatar file user_id with
@@ -254,10 +237,7 @@ let profile_post request =
               ~headers:[ ("Location", "/profile") ]
               "Your avatar was updated!"
           | Error e -> render e request )
-        | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-        | `Expired _ | `Many_tokens _ | `Missing_token _ | `Invalid_token _
-        | `Wrong_session _ | `Wrong_content_type ->
-          Dream.empty `Bad_Request ) )
+        | form -> Utils.handle_invalid_form form ) )
 
 let get_post_image ~thumbnail request =
   let id = Dream.param request "id" in
@@ -347,10 +327,7 @@ let babillard_post request =
               ~headers:[ ("Location", adress) ]
               "Your thread was posted!"
           | Error e -> render e request ) )
-      | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-      | `Expired _ | `Many_tokens _ | `Missing_token _ | `Invalid_token _
-      | `Wrong_session _ | `Wrong_content_type ->
-        Dream.empty `Bad_Request )
+      | form -> Utils.handle_invalid_form form )
 
 let thread_feed_get request =
   let thread_id = Dream.param request "thread_id" in
@@ -401,10 +378,7 @@ let reply_post request =
             ~headers:[ ("Location", adress) ]
             "Your reply was posted!"
         | Error e -> render e request )
-      | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
-      | `Expired _ | `Many_tokens _ | `Missing_token _ | `Invalid_token _
-      | `Wrong_session _ | `Wrong_content_type ->
-        Dream.empty `Bad_Request )
+      | form -> Utils.handle_invalid_form form )
 
 let error_template _error _debug_info response =
   let status = Dream.status response in
diff --git a/src/utils.ml b/src/utils.ml
index 4aae133..751b0d8 100644
--- a/src/utils.ml
+++ b/src/utils.ml
@@ -22,3 +22,9 @@ let logged_in_or_redirect request logged_in =
     let redirect_url = Format.sprintf "/login=?redirect=%s" target in
     Dream.respond ~status:`See_Other ~headers:[ ("Location", redirect_url) ] ""
   | Some user_id -> logged_in user_id
+
+let handle_invalid_form = function
+  | `Ok _ -> Dream.respond ~status:`Bad_Request "invalid form"
+  | `Many_tokens _ | `Missing_token _ | `Invalid_token _ | `Wrong_session _
+  | `Expired _ | `Wrong_content_type ->
+    Dream.empty `Bad_Request