Changeset 246525 in webkit

Timestamp:

Jun 17, 2019 5:14:59 PM (5 years ago)

Author:

achristensen@apple.com

Message:

Fix iOS crash when starting loads with no active DocumentLoader
​https://bugs.webkit.org/show_bug.cgi?id=187360
<rdar://problem/29389084>

Reviewed by Geoff Garen.

When FrameLoader::activeDocumentLoader returns null in the ResourceLoader constructor,
on iOS we will dereference it to ask if it has a frame in an early return in init.
Let's not. If we don't have a DocumentLoader, we don't have a frame and should fail.

Crash reports indicate this crash is related to Beacon and other uses of LoaderStrategy::startPingLoad,
but attempts to make a unit test to reproduce the crash were unsuccessful.

• loader/ResourceLoader.cpp:

(WebCore::ResourceLoader::init):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• loader/ResourceLoader.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2019-06-17  Alex Christensen  <achristensen@webkit.org>
+
+        Fix iOS crash when starting loads with no active DocumentLoader
+        https://bugs.webkit.org/show_bug.cgi?id=187360
+        <rdar://problem/29389084>
+
+        Reviewed by Geoff Garen.
+
+        When FrameLoader::activeDocumentLoader returns null in the ResourceLoader constructor,
+        on iOS we will dereference it to ask if it has a frame in an early return in init.
+        Let's not.  If we don't have a DocumentLoader, we don't have a frame and should fail.
+
+        Crash reports indicate this crash is related to Beacon and other uses of LoaderStrategy::startPingLoad,
+        but attempts to make a unit test to reproduce the crash were unsuccessful.
+
+        * loader/ResourceLoader.cpp:
+        (WebCore::ResourceLoader::init):
+
 2019-06-17  Robin Morisset  <rmorisset@apple.com>
 

trunk/Source/WebCore/loader/ResourceLoader.cpp

@@ -120 +120 @@
 void ResourceLoader::init(ResourceRequest&& clientRequest, CompletionHandler<void(bool)>&& completionHandler)
 {
+#if PLATFORM(IOS_FAMILY)
+    if (!m_documentLoader) {
+        // We should always have a DocumentLoader at this point, but crash reports indicate that it is sometimes null.
+        // See https://bugs.webkit.org/show_bug.cgi?id=187360
+        ASSERT_NOT_REACHED();
+        return completionHandler(false);
+    }
+#endif
     ASSERT(!m_handle);
     ASSERT(m_request.isNull());