[tor-bugs] #6539 [Firefox Patch Issues]: Image cache isolation causes assert crash in debug builds (and other cases?)

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#6539: Image cache isolation causes assert crash in debug builds (and other
cases?)
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 Reporter:  mikeperry                         |          Owner:  mikeperry
     Type:  defect                            |         Status:  new      
 Priority:  major                             |      Milestone:           
Component:  Firefox Patch Issues              |        Version:           
 Keywords:  MikePerry201211d tbb-linkability  |         Parent:  #6528    
   Points:                                    |   Actualpoints:  3        
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Comment(by mcs):

 We fixed several issues but some remain.  Here is what we fixed:

 (1) Added NS_ADDREF() in imgLoader::FindEntryProperties() (accidentally
 removed?)
 (2) Fixed imgLoader::SetHasProxies() to use the new key format.
 (3) Modified imgLoader::GetCacheKey() to not use the new partitioned key
 format for chrome:// images.
 (4) Added some assertions and NULL checks for safety.
 (5) Renamed some parameters for clarity (e.g., key -> imgURI).

 I will attach a patch that shows the above changes.  Stability is much
 improved.

 Change (3) is necessary because the firstPartyURI is NULL when loading
 images referenced by some internal pages such as the bookmarks or history
 sidebars.  Unfortunately, we still see NULL firstPartyURI values for some
 internal image loads such as:
    moz-anno:favicon:http://www.mozilla.org/media/img/firefox/favicon.png
 (when referenced by the history sidebar).

 So -- is the intent that firstPartyURI will always be non-NULL inside the
 image cache?  If so, we need to determine why
 ThirdPartyUtil::GetFirstPartyURI() fails in some cases.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/6539#comment:14>
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