Re: [PATCH v3 2/7] crypto: aead - disallow en/decrypt for non-task or non-softirq context
From: Eric Biggers <ebiggers@kernel.org>
Date: 2021-05-12 21:08:10
Also in:
linux-crypto
On Wed, May 12, 2021 at 08:44:34PM +0200, Ard Biesheuvel wrote:
quoted hunk ↗ jump to hunk
In order to ensure that kernel mode SIMD routines will not need a scalar fallback if they run with softirqs disabled, disallow any use of the AEAD encrypt and decrypt routines from outside of task or softirq context. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> --- crypto/aead.c | 10 ++++++++++ 1 file changed, 10 insertions(+)diff --git a/crypto/aead.c b/crypto/aead.c index 16991095270d..b5304b3d3314 100644 --- a/crypto/aead.c +++ b/crypto/aead.c@@ -87,6 +87,11 @@ int crypto_aead_encrypt(struct aead_request *req) unsigned int cryptlen = req->cryptlen; int ret; + if (!(alg->cra_flags & CRYPTO_ALG_ASYNC) && + WARN_ONCE(!in_task() && !in_serving_softirq(), + "synchronous call from invalid context\n")) + return -EBUSY; + crypto_stats_get(alg); if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY;@@ -104,6 +109,11 @@ int crypto_aead_decrypt(struct aead_request *req) unsigned int cryptlen = req->cryptlen; int ret; + if (!(alg->cra_flags & CRYPTO_ALG_ASYNC) && + WARN_ONCE(!in_task() && !in_serving_softirq(), + "synchronous call from invalid context\n")) + return -EBUSY; + crypto_stats_get(alg); if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY;
This probably should go after crypto_stats_get() so that the error gets counted in the stats (if stats are enabled) -- analogous to how the ENOKEY error is counted. Likewise for the skcipher patch. - Eric _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel