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 skcipher encrypt and decrypt routines from outside of task or softirq context. Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> --- crypto/skcipher.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/crypto/skcipher.c b/crypto/skcipher.c index 93fdacf49697..9bce5350008b 100644 --- a/crypto/skcipher.c +++ b/crypto/skcipher.c @@ -625,6 +625,11 @@ int crypto_skcipher_encrypt(struct skcipher_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_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY; @@ -642,6 +647,11 @@ int crypto_skcipher_decrypt(struct skcipher_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_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY; -- 2.20.1
