From 703417a76090f582eab470b124420b8b6e5d1e92 Mon Sep 17 00:00:00 2001
From: Giovanni Campagna <gcampagna@src.gnome.org>
Date: Sun, 26 Aug 2012 14:54:02 +0200
Subject: [PATCH] ShellUserVerifier: fix cancellation

Ensure that all async callbacks check and ignore G_IO_ERROR_CANCELLED.
Ensure that all runs of authentication have their own GCancellable, so
that .begin() can be called multiple times on the same user verifier.
Check for fingerprint reader when beginning authentication, and not
when reset by GDM.

https://bugzilla.gnome.org/show_bug.cgi?id=682544
---
 js/gdm/util.js        | 54 +++++++++++++++++++++++++++++--------------
 js/ui/unlockDialog.js |  1 +
 2 files changed, 38 insertions(+), 17 deletions(-)

diff --git a/js/gdm/util.js b/js/gdm/util.js
index d07d1b2e5..d2e537a4c 100644
--- a/js/gdm/util.js
+++ b/js/gdm/util.js
@@ -79,18 +79,17 @@ const ShellUserVerifier = new Lang.Class({
 
         this._settings = new Gio.Settings({ schema: LOGIN_SCREEN_SCHEMA });
 
-        this._cancellable = new Gio.Cancellable();
-
         this._fprintManager = new Fprint.FprintManager();
-        this._checkForFingerprintReader();
-
         this._realmManager = new Realmd.Manager();
     },
 
     begin: function(userName, hold) {
+        this._cancellable = new Gio.Cancellable();
         this._hold = hold;
         this._userName = userName;
 
+        this._checkForFingerprintReader();
+
         if (userName) {
             // If possible, reauthenticate an already running session,
             // so any session specific credentials get updated appropriately
@@ -102,15 +101,18 @@ const ShellUserVerifier = new Lang.Class({
     },
 
     cancel: function() {
-        this._cancellable.cancel();
+        if (this._cancellable)
+            this._cancellable.cancel();
 
         if (this._userVerifier)
             this._userVerifier.call_cancel_sync(null);
-        this._cancellable = new Gio.Cancellable();
     },
 
     clear: function() {
-        this._cancellable.cancel();
+        if (this._cancellable) {
+            this._cancellable.cancel();
+            this._cancellable = null;
+        }
 
         if (this._userVerifier) {
             this._userVerifier.run_dispose();
@@ -144,11 +146,12 @@ const ShellUserVerifier = new Lang.Class({
             this._hold.release();
         } catch (e) {
             if (this._reauthOnly) {
+                if (e.matches(Gio.IOErrorEnum, Gio.IOErrorEnum.CANCELLED))
+                    return;
+
                 logError(e, 'Failed to open reauthentication channel');
-
-                this._hold.release();
                 this.emit('verification-failed');
-
+                this._hold.release();
                 return;
             }
 
@@ -159,10 +162,14 @@ const ShellUserVerifier = new Lang.Class({
     },
 
     _userVerifierGot: function(client, result) {
-        this._userVerifier = client.get_user_verifier_finish(result);
+        try {
+            this._userVerifier = client.get_user_verifier_finish(result);
+        } catch(e if e.matches(Gio.IOErrorEnum, Gio.ErrorEnum.CANCELLED)) {
+            return;
+        }
+
         this._connectSignals();
         this._beginVerification();
-
         this._hold.release();
     },
 
@@ -184,7 +191,12 @@ const ShellUserVerifier = new Lang.Class({
                                                                 this._userName,
                                                                 this._cancellable,
                                                                 Lang.bind(this, function(obj, result) {
-                obj.call_begin_verification_for_user_finish(result);
+                try {
+                    obj.call_begin_verification_for_user_finish(result);
+                } catch(e if e.matches(Gio.IOErrorEnum, Gio.IOErrorEnum.CANCELLED)) {
+                    return;
+                }
+
                 this._hold.release();
             }));
 
@@ -195,7 +207,12 @@ const ShellUserVerifier = new Lang.Class({
                                                                     this._userName,
                                                                     this._cancellable,
                                                                     Lang.bind(this, function(obj, result) {
-                    obj.call_begin_verification_for_user_finish(result);
+                    try {
+                        obj.call_begin_verification_for_user_finish(result);
+                    } catch(e if e.matches(Gio.IOErrorEnum, Gio.IOErrorEnum.CANCELLED)) {
+                        return;
+                    }
+
                     this._hold.release();
                 }));
             }
@@ -203,7 +220,12 @@ const ShellUserVerifier = new Lang.Class({
             this._userVerifier.call_begin_verification(PASSWORD_SERVICE_NAME,
                                                        this._cancellable,
                                                        Lang.bind(this, function(obj, result) {
-                obj.call_begin_verification_finish(result);
+                try {
+                    obj.call_begin_verification_finish(result);
+                } catch(e if e.matches(Gio.IOErrorEnum, Gio.IOErrorEnum.CANCELLED)) {
+                    return;
+                }
+
                 this._hold.release();
             }));
         }
@@ -271,8 +293,6 @@ const ShellUserVerifier = new Lang.Class({
         this._userVerifier.run_dispose();
         this._userVerifier = null;
 
-        this._checkForFingerprintReader();
-
         this.emit('reset');
     },
 
diff --git a/js/ui/unlockDialog.js b/js/ui/unlockDialog.js
index a4d666dab..da10cecc1 100644
--- a/js/ui/unlockDialog.js
+++ b/js/ui/unlockDialog.js
@@ -166,6 +166,7 @@ const UnlockDialog = new Lang.Class({
     },
 
     _reset: function() {
+        this._userVerifier.clear();
         this._userVerifier.begin(this._userName, new Batch.Hold());
     },