RFR: 8267314: Loading some animated GIFs fails with ArrayIndexOutOfBoundsException: Index 4096 out of bounds for length 4096 [v2]

[Ambarish Rapte]

On Fri, 21 May 2021 19:24:19 GMT, Jose Pereda <jpereda at openjdk.org> wrote:

>> This PR limits the `tableIndex` value, used by the LZWDecoder algorithm in `GIFImageLoader2`, to avoid a potential AIOOB exception that happens on some animated GIFs, to the maximum size of the tables used (4096). 
>> 
>> In some occasions loading an animated GIF like the one used in the included test, doesn't throw such exception, because we `allow partially loaded animated images` in `ImageStorage`, but only a few frames are loaded.
>> 
>> In theory, greater values of such index would operate over completely full tables, so there is no need to add new values in this case, and therefore, there is no risk in limiting the value to 4096.
>> 
>> This PR will prevent the exception and all the frames should load. The included test passes now (and fails loading only 10 frames out of 44 without the proposed fix).
>
> Jose Pereda has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Modify test to avoid online resources

Looks good to me. Did sanity check by loading different sized gif images.

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Marked as reviewed by arapte (Reviewer).

PR: https://git.openjdk.java.net/jfx/pull/513