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From:   Thara Gopinath <thara.gopinath@linaro.org>
To:     agross@kernel.org, bjorn.andersson@linaro.org,
        herbert@gondor.apana.org.au, davem@davemloft.net,
        robh+dt@kernel.org, sboyd@kernel.org, mturquette@baylibre.com
Cc:     linux-arm-msm@vger.kernel.org, linux-crypto@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-clk@vger.kernel.org
Subject: [PATCH 4/6] drivers:crypto:qce: Fix SHA result buffer corruption issues.
Date:   Tue, 17 Nov 2020 08:47:12 -0500
Message-Id: <20201117134714.3456446-5-thara.gopinath@linaro.org>
In-Reply-To: <20201117134714.3456446-1-thara.gopinath@linaro.org>
References: <20201117134714.3456446-1-thara.gopinath@linaro.org>
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Partial hash was being copied into the final result buffer without the
entire message block processed. Depending on how the end user processes
this result buffer, errors vary from result buffer corruption to result
buffer poisoing. Fix this issue by ensuring that only the final hash value
is copied into the result buffer.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
---
 drivers/crypto/qce/sha.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/qce/sha.c b/drivers/crypto/qce/sha.c
index 87be96a0b0bb..61c418c12345 100644
--- a/drivers/crypto/qce/sha.c
+++ b/drivers/crypto/qce/sha.c
@@ -48,7 +48,7 @@ static void qce_ahash_done(void *data)
 	dma_unmap_sg(qce->dev, &rctx->result_sg, 1, DMA_FROM_DEVICE);
 
 	memcpy(rctx->digest, result->auth_iv, digestsize);
-	if (req->result)
+	if (req->result && rctx->last_blk)
 		memcpy(req->result, result->auth_iv, digestsize);
 
 	rctx->byte_count[0] = cpu_to_be32(result->auth_byte_count[0]);
-- 
2.25.1