Changeset 267412 in webkit

Timestamp:

Sep 22, 2020, 9:22:33 AM (6 years ago)

Author:

beidson@apple.com

Message:

Crashtracer inside PDFPlugin::createScrollbar.
<rdar://problem/69256031> and ​https://bugs.webkit.org/show_bug.cgi?id=216810

Reviewed by Tim Horton.

To quote Tim from r264945:
No new tests; timing is such that I can't reproduce without inserting
intentional delays into the main thread hops, which is further than
I'm willing to go for a test.

This is a speculative fix due to the aforementioned reproducibility issue.

• WebProcess/Plugins/PDF/PDFPlugin.mm:

(WebKit::PDFPlugin::installPDFDocument): With all the past fixes in place, its apparent

the plug-in HAS been torn down, and it's somewhat common to bypass the other "hasBeenDestroyed"
checks. So put an explicit check here followed by an explicit release assert.

Location:

trunk/Source/WebKit

Files:

• ChangeLog (modified) (1 diff)
• WebProcess/Plugins/PDF/PDFPlugin.mm (modified) (1 diff)

trunk/Source/WebKit/ChangeLog

@@ +1 @@
+2020-09-22  Brady Eidson  <beidson@apple.com>
+
+        Crashtracer inside PDFPlugin::createScrollbar.
+        <rdar://problem/69256031> and https://bugs.webkit.org/show_bug.cgi?id=216810
+
+        Reviewed by Tim Horton.
+
+        To quote Tim from r264945:
+        No new tests; timing is such that I can't reproduce without inserting
+        intentional delays into the main thread hops, which is further than
+        I'm willing to go for a test.
+
+        This is a speculative fix due to the aforementioned reproducibility issue.
+        
+        * WebProcess/Plugins/PDF/PDFPlugin.mm:
+        (WebKit::PDFPlugin::installPDFDocument): With all the past fixes in place, its apparent
+          the plug-in HAS been torn down, and it's somewhat common to bypass the other "hasBeenDestroyed"
+          checks. So put an explicit check here followed by an explicit release assert.
+
 2020-09-22  Brian Burg  <bburg@apple.com>
 

trunk/Source/WebKit/WebProcess/Plugins/PDF/PDFPlugin.mm

@@ -1586 +1586 @@
     LOG(IncrementalPDF, "Installing PDF document");
 
+    if (m_hasBeenDestroyed)
+        return;
+
+    // If we haven't been destroyed yet, there must still be a PluginController
+    RELEASE_ASSERT(controller());
+
 #if HAVE(INCREMENTAL_PDF_APIS)
     maybeClearHighLatencyDataProviderFlag();