Bug 187121 – WebKitLegacy: Can trigger recursive loads triggering debug assertions

• Status: RESOLVED
• Resolution: FIXED
• Component: WebKit Misc.

[Brent Fulgham]

While investigating Bug 187008 I found that some WebKitLegacy clients trigger recursive loads while cancelling the loading of web content into a WebView.

This has the following impacts:

1. FrameLoader::continueLoadAfterNavigationPolicy gets entered with a nullptr Policy Document Loader as well as a nullptr Provisional Document Loader. If we continue in this state, we hit a ton of assertions, and eventually crash with a nullptr exception. If we return early, the cancel and alternate page load complete properly.

2. WebFrameLoaderClient::dispatchDidStartProvisionalLoad can be re-entered which triggers a set of assertions and eventually a nullptr dereference. If we keep track of whether we have started a load on the current client object, and return early in those cases, the cancel and alternate page load complete properly.

[Brent Fulgham]

<rdar://problem/41259430>

[Brent Fulgham]

Created attachment 343765 [details]
Patch

[EWS Watchlist]

Comment on attachment 343765 [details]
Patch

Attachment 343765 [details] did not pass win-ews (win):
Output: https://webkit-queues.webkit.org/results/8365540

New failing tests:
http/tests/security/canvas-remote-read-remote-video-blocked-no-crossorigin.html

[EWS Watchlist]

Created attachment 343783 [details]
Archive of layout-test-results from ews202 for win-future

The attached test failures were seen while running run-webkit-tests on the win-ews.
Bot: ews202  Port: win-future  Platform: CYGWIN_NT-6.1-2.9.0-0.318-5-3-x86_64-64bit

[Chris Dumez]

Created attachment 343934 [details]
Patch

[EWS Watchlist]

Comment on attachment 343934 [details]
Patch

Attachment 343934 [details] did not pass win-ews (win):
Output: https://webkit-queues.webkit.org/results/8387296

New failing tests:
http/tests/security/local-video-source-from-remote.html

[EWS Watchlist]

Created attachment 343949 [details]
Archive of layout-test-results from ews200 for win-future

The attached test failures were seen while running run-webkit-tests on the win-ews.
Bot: ews200  Port: win-future  Platform: CYGWIN_NT-6.1-2.9.0-0.318-5-3-x86_64-64bit

[Brent Fulgham]

Comment on attachment 343934 [details]
Patch

r=me

[WebKit Commit Bot]

Comment on attachment 343934 [details]
Patch

Clearing flags on attachment: 343934

Committed r233374: <https://trac.webkit.org/changeset/233374>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.