539686 - [HTML5] tests/content/base/test/test_CSP.html fails

Status: RESOLVED FIXED

(Core :: DOM: HTML Parser, defect, P1)

Description

[Henri Sivonen (:hsivonen)]

tests/content/base/test/test_CSP.html fails with:
img_bad test: http://example.org/tests/content/base/test/file_CSP.sjs?testid=img_bad&type=img/png allowed by csp - got false, expected true

Comment 1

[Henri Sivonen (:hsivonen)]

The test was backed out.

Comment 2

[Sid Stamm [:geekboy or :sstamm]]

This was caused by an <img> tag not being closed properly.  I changed the test from this:

<img src="URI" />

to this:

<img src="URI"></img>

And the test passed. Additionally, changing the tag to have no closing tag:

<img src="URI">

Also caused the test to fail. The reason the test was failing is not clear, but I believe it has something to do with a malformed tag ignoring results from nsIContentPolicys.  We will be checking this test in again (but I will fix it to play nice with the current html5 parser). 

The <img> tag is defined as a "void element" by HTML5 (http://www.w3.org/TR/html5/syntax.html#void-elements), which means it doesn't require a closing tag.  Because adding a closing tag makes this test succeed, I think there might be a bug in the parser.

I'll try to create a reduced testcase for this, since I don't think it's a problem isolated to CSP or our test case.

Comment 3

[Henri Sivonen (:hsivonen)]

(In reply to comment #2)
> This was caused by an <img> tag not being closed properly.  I changed the test
> from this:
> 
> <img src="URI" />
> 
> to this:
> 
> <img src="URI"></img>
> 
> And the test passed.

I see <img ... /> only in file_CSP_main.html, but it seems to me that file gets loaded via XHR on the server side and never directly into e.g. an iframe. Does the file get mangled before it reaches the HTML5 parser?

As far as I can tell, <img>, <img/>, <img /> and <img></img> all create the same DOM in the HTML5 parser.

Comment 4

[Sid Stamm [:geekboy or :sstamm]]

The XHR (which is just there to provide the CSP HTTP header) doesn't seem to mangle the file at all.  I just verified that the content served is the same as the source.  

One thing that's kind of strange is reproducing the failure doesn't work all the time.  It seems re-running the tests after switching the parser on makes them pass:

1.  Launch CSP tests:
  TEST_PATH=content/base/test/test_CSP.html make -C $OBJDIR mochitest-plain
2.  Watch the 16 tests pass
3.  Load about:config in a new tab and toggle html5.enabled to true
4.  Reload the test page, watch the one test fail.
5.  Reload the test page, watch all 16 pass.

So now I'm confused...

Comment 5

[Sid Stamm [:geekboy or :sstamm]]

It appears that content policies weren't always consulted when preloading images.  This revision seems to have fixed the problem.  I no longer see the broken unit test using the steps in comment 4.

http://hg.mozilla.org/mozilla-central/rev/02135cbe7432