diff mbox series

[v2,4/9] crypto: aead - disallow en/decrypt for non-task or non-softirq context

Message ID 20210302090118.30666-5-ardb@kernel.org (mailing list archive)
State Not Applicable
Delegated to: Herbert Xu
Headers show
Series running kernel mode SIMD with softirqs disabled | expand

Commit Message

Ard Biesheuvel March 2, 2021, 9:01 a.m. UTC
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 mbox series

Patch

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;