[PATCH v2 5/8] crypto: qce - Use a fallback for AES-CTR with a partial final block

[Bartosz Golaszewski]

ctr(aes) is registered with a block size of 1, so the crypto API hands
the driver requests whose length is not a multiple of the AES block
size. The crypto engine, however, stalls waiting for a full block of
input in that case, leaving the operation incomplete and failing the
request (and the crypto self-tests) with a hardware operation error.

Route AES-CTR requests with a partial final block to the software
fallback, which already handles the other cases the engine cannot.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: bb5c863b3d3c ("crypto: qce - fix ctr-aes-qce block, chunk sizes")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>
---
 drivers/crypto/qce/skcipher.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/crypto/qce/skcipher.c b/drivers/crypto/qce/skcipher.c
index 379b45d2cd952a39c387e84af71238b53f7737e9..cf34278da30b1ffccf230ed194faae2352cb8550 100644
--- a/drivers/crypto/qce/skcipher.c
+++ b/drivers/crypto/qce/skcipher.c
@@ -277,9 +277,12 @@ static int qce_skcipher_crypt(struct skcipher_request *req, int encrypt)
 	 * AES-XTS request with len > QCE_SECTOR_SIZE and
 	 * is not a multiple of it.(Revisit this condition to check if it is
 	 * needed in all versions of CE)
+	 * AES-CTR with a partial final block (the CE stalls waiting for a full
+	 * block of input).
 	 */
 	if (IS_AES(rctx->flags) &&
 	    ((keylen != AES_KEYSIZE_128 && keylen != AES_KEYSIZE_256) ||
+	    (IS_CTR(rctx->flags) && !IS_ALIGNED(req->cryptlen, AES_BLOCK_SIZE)) ||
 	    (IS_XTS(rctx->flags) && ((req->cryptlen <= aes_sw_max_len) ||
 	    (req->cryptlen > QCE_SECTOR_SIZE &&
 	    req->cryptlen % QCE_SECTOR_SIZE))))) {

-- 
2.47.3