crypto: qat - fix parameter check in aead encryption

Commit Message

Giovanni Cabiddu May 27, 2020, 10:18 p.m. UTC

Return -EINVAL if the input digest size and/or cipher
length is zero or the cipher length is not multiple of a block.
These additional parameter checks prevent an undefined device behaviour.

Signed-off-by: Giovanni Cabiddu <[e-mail]>
---
 drivers/crypto/qat/qat_common/qat_algs.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

Comments

Herbert Xu June 12, 2020, 3:28 a.m. UTC | #1

On Wed, May 27, 2020 at 11:18:52PM +0100, Giovanni Cabiddu wrote:
> Return -EINVAL if the input digest size and/or cipher
> length is zero or the cipher length is not multiple of a block.
> These additional parameter checks prevent an undefined device behaviour.

But a zero-length encryption is valid for AEAD.  If this triggers
an issue in the hardware, then you must fallback to software rather
than rejecting it.

Cheers,

Patch

diff --git a/drivers/crypto/qat/qat_common/qat_algs.c b/drivers/crypto/qat/qat_common/qat_algs.c
index 9df4aebf37ca..00e10a4d578a 100644
--- a/drivers/crypto/qat/qat_common/qat_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_algs.c
@@ -825,8 +825,15 @@  static int qat_alg_aead_dec(struct aead_request *areq)
 	struct icp_qat_fw_la_auth_req_params *auth_param;
 	struct icp_qat_fw_la_bulk_req *msg;
 	int digst_size = crypto_aead_authsize(aead_tfm);
+	u32 cipher_length = areq->cryptlen - digst_size;
 	int ret, ctr = 0;
 
+	if (!digst_size || !areq->cryptlen || !cipher_length)
+		return -EINVAL;
+
+	if (cipher_length % AES_BLOCK_SIZE != 0)
+		return -EINVAL;
+
 	ret = qat_alg_sgl_to_bufl(ctx->inst, areq->src, areq->dst, qat_req);
 	if (unlikely(ret))
 		return ret;
@@ -840,7 +847,7 @@  static int qat_alg_aead_dec(struct aead_request *areq)
 	qat_req->req.comn_mid.src_data_addr = qat_req->buf.blp;
 	qat_req->req.comn_mid.dest_data_addr = qat_req->buf.bloutp;
 	cipher_param = (void *)&qat_req->req.serv_specif_rqpars;
-	cipher_param->cipher_length = areq->cryptlen - digst_size;
+	cipher_param->cipher_length = cipher_length;
 	cipher_param->cipher_offset = areq->assoclen;
 	memcpy(cipher_param->u.cipher_IV_array, areq->iv, AES_BLOCK_SIZE);
 	auth_param = (void *)((uint8_t *)cipher_param + sizeof(*cipher_param));
@@ -869,6 +876,12 @@  static int qat_alg_aead_enc(struct aead_request *areq)
 	uint8_t *iv = areq->iv;
 	int ret, ctr = 0;
 
+	if (!areq->cryptlen)
+		return -EINVAL;
+
+	if (areq->cryptlen % AES_BLOCK_SIZE != 0)
+		return -EINVAL;
+
 	ret = qat_alg_sgl_to_bufl(ctx->inst, areq->src, areq->dst, qat_req);
 	if (unlikely(ret))
 		return ret;