Bug 105218 – [ANGLE] Use of uninitialized memory in ArrayBoundsClamper

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Max Vujovic]

TIntermBinary::addIndexClamp is uninitialized when the compile flag SH_CLAMP_INDIRECT_ARRAY_BOUNDS is not set. Then, addIndexClamp is used in OutputGLSLBase. CSS Shaders needs to do a first validation pass without the SH_CLAMP_INDIRECT_ARRAY_BOUNDS flag and its effects. However, sometimes addIndexClamp is true, which inserts clamping code that causes the a shader to fail compilation at the WebGL level.

Patch coming up.

[Max Vujovic]

Created attachment 179808 [details]
Patch

Style bot never likes ANGLE changes, so please ignore her.

[WebKit Review Bot]

Attachment 179808 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/ThirdParty/ANGLE/ChangeLog', u'Sour..." exit_code: 1
Source/ThirdParty/ANGLE/src/compiler/intermediate.h:392:  Missing space inside { }.  [whitespace/braces] [5]
Total errors found: 1 in 2 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Dean Jackson]

We should make sure this gets back to ANGLE.

Unfortunately I cannot contribute to ANGLE under its current license, but any code changes in WebKit are available under a BSD license. So Max, maybe you could contribute this and the original array clamper?

[Max Vujovic]

Thanks for the review!

(In reply to comment #3)
> We should make sure this gets back to ANGLE.
> 
> Unfortunately I cannot contribute to ANGLE under its current license, but any code changes in WebKit are available under a BSD license. So Max, maybe you could contribute this and the original array clamper?

Yes, definitely. I can do that.

If there's no hurry right now, I'll plan on doing it early January when I get back from holiday break.

[Build Bot]

Comment on attachment 179808 [details]
Patch

Attachment 179808 [details] did not pass mac-ews (mac):
Output: http://queues.webkit.org/results/15371922

New failing tests:
inspector/profiler/heap-snapshot.html

[Max Vujovic]

Created attachment 179960 [details]
Patch

EWS failure seems unrelated. Running it again to double check.

[WebKit Review Bot]

Attachment 179960 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/ThirdParty/ANGLE/ChangeLog', u'Sour..." exit_code: 1
Source/ThirdParty/ANGLE/src/compiler/intermediate.h:392:  Missing space inside { }.  [whitespace/braces] [5]
Total errors found: 1 in 2 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Max Vujovic]

Comment on attachment 179960 [details]
Patch

Bots are green. Setting cq+.

[WebKit Review Bot]

Comment on attachment 179960 [details]
Patch

Rejecting attachment 179960 [details] from commit-queue.

Failed to run "['/mnt/git/webkit-commit-queue/Tools/Scripts/webkit-patch', '--status-host=queues.webkit.org', '-..." exit_code: 1

/mnt/git/webkit-commit-queue/Source/ThirdParty/ANGLE/ChangeLog neither lists a valid reviewer nor contains the string "Unreviewed" or "Rubber stamp" (case insensitive).

Full output: http://queues.webkit.org/results/15418181

[Max Vujovic]

Created attachment 179983 [details]
Patch

Add reviewer entry in ChangeLog.

[WebKit Review Bot]

Attachment 179983 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/ThirdParty/ANGLE/ChangeLog', u'Sour..." exit_code: 1
Source/ThirdParty/ANGLE/src/compiler/intermediate.h:392:  Missing space inside { }.  [whitespace/braces] [5]
Total errors found: 1 in 2 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[WebKit Review Bot]

Comment on attachment 179983 [details]
Patch

Clearing flags on attachment: 179983

Committed r138048: <http://trac.webkit.org/changeset/138048>

[WebKit Review Bot]

All reviewed patches have been landed.  Closing bug.