From: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Date: Mon, 19 Oct 2026 16:46:06 +0200
Subject: [PATCH v12 2/4] crypto: qce - Use a fallback for AES-CTR with a
 partial final block
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Message-Id: <20261019-qce-fixes-skcipher-v12-2-046e6be9bd83@oss.qualcomm.com>
References: <20261019-qce-fixes-skcipher-v12-0-046e6be9bd83@oss.qualcomm.com>
In-Reply-To: <20261019-qce-fixes-skcipher-v12-0-046e6be9bd83@oss.qualcomm.com>
To: Bartosz Golaszewski <brgl@kernel.org>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>,
        Eneas U de Queiroz <cotequeiroz@gmail.com>,
        Kuldeep Singh <kuldeep.singh@oss.qualcomm.com>,
        Eric Biggers <ebiggers@kernel.org>,
        Demi Marie Obenour <demiobenour@gmail.com>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konradybcio@kernel.org>,
        Russell King <linux@armlinux.org.uk>, Abel Vesa <abelvesa@kernel.org>
Cc: linux-crypto@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>,
        stable@vger.kernel.org, Pankaj Patil <pankaj.patil@oss.qualcomm.com>

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@vger.kernel.org
Fixes: bb5c863b3d3c ("crypto: qce - fix ctr-aes-qce block, chunk sizes")
Tested-by: Kuldeep Singh <kuldeep.singh@oss.qualcomm.com>
Tested-by: Pankaj Patil <pankaj.patil@oss.qualcomm.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 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 d9a5b255015341e741515bdfd6ff54bd3b24f1e3..8d4cd1d08c0e9d78f044057ecb45e5aa8b9a40a3 100644
--- a/drivers/crypto/qce/skcipher.c
+++ b/drivers/crypto/qce/skcipher.c
@@ -248,9 +248,12 @@ 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