Changeset 271467 in webkit

Timestamp:

Jan 13, 2021, 3:19:23 PM (6 years ago)

Author:

jiewen_tan@apple.com

Message:

Crash at SOAuthorizationSession::dismissViewController
​https://bugs.webkit.org/show_bug.cgi?id=220482
<rdar://problem/72375494>

Reviewed by Darin Adler.

A crash report suggests that SOAuthorizationSession::dismissViewController could crash at evaluating m_page.
This could only happen if the SOAuthorizationSession object is freed. The stack trace starts with callbacks
from NSNotificationCenter, which capture a RefPtr of the SOAuthorizationSession object and should guarantee
the lifetime of the object. So it contradicts the crash report.

One of the possible explanations is that the RefPtr is somehow over-released within NSNotificationCenter since
it's not thread-safe. To fix that, the RefPtr can be made thread-safe.

No tests.

• UIProcess/Cocoa/SOAuthorization/SOAuthorizationSession.mm:

(WebKit::SOAuthorizationSession::dismissViewController):

Location:

trunk/Source/WebKit

Files:

• ChangeLog (modified) (1 diff)
• UIProcess/Cocoa/SOAuthorization/SOAuthorizationSession.h (modified) (2 diffs)

trunk/Source/WebKit/ChangeLog

@@ +1 @@
+2021-01-13  Jiewen Tan  <jiewen_tan@apple.com>
+
+        Crash at SOAuthorizationSession::dismissViewController
+        https://bugs.webkit.org/show_bug.cgi?id=220482
+        <rdar://problem/72375494>
+
+        Reviewed by Darin Adler.
+
+        A crash report suggests that SOAuthorizationSession::dismissViewController could crash at evaluating m_page.
+        This could only happen if the SOAuthorizationSession object is freed. The stack trace starts with callbacks
+        from NSNotificationCenter, which capture a RefPtr of the SOAuthorizationSession object and should guarantee
+        the lifetime of the object. So it contradicts the crash report.
+
+        One of the possible explanations is that the RefPtr is somehow over-released within NSNotificationCenter since
+        it's not thread-safe. To fix that, the RefPtr can be made thread-safe.
+
+        No tests.
+
+        * UIProcess/Cocoa/SOAuthorization/SOAuthorizationSession.mm:
+        (WebKit::SOAuthorizationSession::dismissViewController):
+
 2021-01-13  Wenson Hsieh  <wenson_hsieh@apple.com>
 

trunk/Source/WebKit/UIProcess/Cocoa/SOAuthorization/SOAuthorizationSession.h

@@ -30 +30 @@
 #include <pal/spi/cocoa/AppSSOSPI.h>
 #include <wtf/Forward.h>
-#include <wtf/RefCounted.h>
 #include <wtf/RetainPtr.h>
+#include <wtf/ThreadSafeRefCounted.h>
 #include <wtf/WeakObjCPtr.h>
 #include <wtf/WeakPtr.h>
@@ -52 +52 @@
 
 // A session will only be executed once.
-class SOAuthorizationSession : public RefCounted<SOAuthorizationSession>, public CanMakeWeakPtr<SOAuthorizationSession> {
+class SOAuthorizationSession : public ThreadSafeRefCounted<SOAuthorizationSession, WTF::DestructionThread::MainRunLoop>, public CanMakeWeakPtr<SOAuthorizationSession> {
 public:
     enum class InitiatingAction : uint8_t {