Re: [patch] Fix BZ #17916 fopen unbounded stack usage for ccs= modes

[Paul Pluzhnikov <ppluzhnikov at gmail dot com>]

On Sun, Feb 22, 2015 at 12:59 PM, Florian Weimer <fw@deneb.enyo.de> wrote:

Thanks for the review.

>> Attached patch fixes BZ #17916 fopen unbounded stack usage for ccs= modes
>> Tested on Linux/x86_64, no failures.
>
> This should have a test case.

I am not sure how to test for unbounded stack use.
I've added a test for humungous ccs= value.

> There is a missing NULL check on the malloc result.  I don't think the
> alloca optimization makes sense because this functionality is used so
> rarely, and the function allocates on the heap anyway.  Just use
> malloc unconditionally; it will result in smaller code.

Done.

2015-02-22  Paul Pluzhnikov  <ppluzhnikov@google.com>

        [BZ #17916]
        * libio/fileops.c (_IO_new_file_fopen): Limit stack use
        * libio/tst-fopenloc.c (do_test): Add a large ccs= test




-- 
Paul Pluzhnikov

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