Messages in this thread | | | From | Rusty Russell <> | Subject | Re: [RFC v2 1/7] integrity: added digest calculation function | Date | Mon, 20 Aug 2012 12:29:33 +0930 |
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On Wed, 15 Aug 2012 21:43:06 +0300, Dmitry Kasatkin <dmitry.kasatkin@intel.com> wrote: > + } else { > + struct { > + struct shash_desc shash; > + char ctx[crypto_shash_descsize(tfm)]; > + } desc;
Linus had a rant a while ago about using variable-sized stack vars in the kernel (can't find a reference right now, sorry).
The problem is that either you know there's a limit to crypto_shash_descsize(), in which case you can just use this here, or you don't know, in which case, this risks a stack oveflow.
Cheers, Rusty.
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