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Date:   Wed, 19 May 2021 19:29:30 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        ebiggers@kernel.org, will@kernel.org, kernel-team@android.com
Subject: Re: [PATCH v4 2/7] crypto: aead - disallow en/decrypt for non-task
 or non-softirq context
Message-ID: <20210519112930.sgy3trqczyfok7mn@gondor.apana.org.au>
References: <20210519112239.33664-1-ardb@kernel.org>
 <20210519112239.33664-3-ardb@kernel.org>
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On Wed, May 19, 2021 at 01:22:34PM +0200, Ard Biesheuvel wrote:
>
>  	crypto_stats_get(alg);
> -	if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY)
> +	if (!(alg->cra_flags & CRYPTO_ALG_ASYNC) &&
> +	    WARN_ONCE(!in_task() && !in_serving_softirq(),
> +		      "synchronous call from invalid context\n"))
> +		ret = -EBUSY;

I don't think we've ever supported crypto in hard IRQ contexts.
So this should be done regardless of ASYNC.

Then again, do we really need this since the assumption has
always been that the crypto API can only be invoked in user or
softirq context?

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