From: Olivier Goffart <ogoffart@woboq.com>
Date: Tue, 28 Mar 2017 13:11:58 +0000 (+0200)
Subject: AccountState: Attempt to fix a crash
X-Git-Tag: archive/raspbian/3.16.7-1_deb13u1+rpi1~1^2~773^2~29
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=85afa4788b7ad16d1959a9660ba16b4393601345;p=nextcloud-desktop.git

AccountState: Attempt to fix a crash

Backtrace from the crash reporter:

Crash: EXCEPTION_ACCESS_VIOLATION_READ at 0x21
  File "qcoreapplication.cpp", line 1281, in QCoreApplication::postEvent
  File "qobject.cpp", line 2125, in QObject::deleteLater
  File "connectionvalidator.cpp", line 240, in OCC::ConnectionValidator::reportResult
  File "connectionvalidator.cpp", line 206, in OCC::ConnectionValidator::slotAuthFailed
  File "moc_connectionvalidator.cpp", line 127, in OCC::ConnectionValidator::qt_static_metacall
  File "qobject.cpp", line 3716, in QMetaObject::activate
  File "moc_networkjobs.cpp", line 653, in OCC::PropfindJob::finishedWithError
  File "networkjobs.cpp", line 570, in OCC::PropfindJob::finished

I believe the problem is caused because 'this' was deleted in ConnectionValidator::reportResult
as the signal connectionResult gets emited. The AccountState::slotConnectionValidatorResult
slot does indeed call slotInvalidCredentials which might call {Shibboleth,Http}Credentials::fetchFromKeychain
which might emit fetched directly, which will call AccountState::slotCredentialsFetched
which deletes the _connectionValidator

So use deleteLater when deleting the _connectionValidator, hoping this helps
---

diff --git a/src/gui/accountstate.cpp b/src/gui/accountstate.cpp
index 38bae16a9..fb2dc5360 100644
--- a/src/gui/accountstate.cpp
+++ b/src/gui/accountstate.cpp
@@ -281,9 +281,12 @@ void AccountState::slotCredentialsFetched(AbstractCredentials* credentials)
 
     _waitingForNewCredentials = false;
 
-    // When new credentials become available we always want to restart the
-    // connection validation, even if it's currently running.
-    delete _connectionValidator;
+    if (_connectionValidator) {
+        // When new credentials become available we always want to restart the
+        // connection validation, even if it's currently running.
+        _connectionValidator->deleteLater();
+        _connectionValidator = 0;
+    }
 
     checkConnectivity();
 }
@@ -298,9 +301,12 @@ void AccountState::slotCredentialsAsked(AbstractCredentials* credentials)
         return;
     }
 
-    // When new credentials become available we always want to restart the
-    // connection validation, even if it's currently running.
-    delete _connectionValidator;
+    if (_connectionValidator) {
+        // When new credentials become available we always want to restart the
+        // connection validation, even if it's currently running.
+        _connectionValidator->deleteLater();
+        _connectionValidator = 0;
+    }
 
     checkConnectivity();
 }