linux-kernel - Re: [PATCH] crypto: do not free algorithm before using

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Message-ID: <20181129065711.7renu7xnxzp7sr2d@gondor.apana.org.au>
Date:   Thu, 29 Nov 2018 14:57:11 +0800
From:   Herbert Xu <herbert@...dor.apana.org.au>
To:     Pan Bian <bianpan2016@....com>
Cc:     "David S. Miller" <davem@...emloft.net>,
        linux-crypto@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] crypto: do not free algorithm before using

On Thu, Nov 22, 2018 at 06:00:16PM +0800, Pan Bian wrote:
> In multiple functions, the algorithm fields are read after its reference
> is dropped through crypto_mod_put. In this case, the algorithm memory
> may be freed, resulting in use-after-free bugs. This patch delays the
> put operation until the algorithm is never used.
> 
> Signed-off-by: Pan Bian <bianpan2016@....com>

Patch applied.  Thanks!

BTW, this problem exists in almost every other skcipher template,
e.g., in ctr.  Are you working on a fix for them too?

Cheers,
-- 
Email: Herbert Xu <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt