MLK-14765: Fix DCP Aes timeout issues when used with CTS

The DCP driver does not obey cryptlen, when doing CTS this results in
passing to hardware input stream lengths which are not multiple of
block size. This causes the hw to misbehave. Also not honoring
cryptlen makes CTS fail. A check was introduced to prevent future
erroneous stream lengths from reaching the hardware. Code which is
splitting the input stream in internal DCP pages was changed to obey
cryptlen.

Signed-off-by: Radu Solea <radu.solea@nxp.com>

1 files changed, 25 insertions, 2 deletions

diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c
index 151ea655c398..dec79a084b09 100644
--- a/drivers/crypto/mxs-dcp.c
+++ b/drivers/crypto/mxs-dcp.c
@@ -236,6 +236,12 @@ static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
 	dma_addr_t dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
 					     DCP_BUF_SZ, DMA_FROM_DEVICE);
 
+	if (actx->fill % AES_BLOCK_SIZE) {
+		dev_err(sdcp->dev, "Invalid block size!\n");
+		ret = -EINVAL;
+		goto aes_done_run;
+	}
+
 	/* Fill in the DMA descriptor. */
 	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
 		    MXS_DCP_CONTROL0_INTERRUPT |
@@ -265,6 +271,7 @@ static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
 
 	ret = mxs_dcp_start_dma(actx);
 
+aes_done_run:
 	dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
 			 DMA_TO_DEVICE);
 	dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
@@ -291,13 +298,15 @@ static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
 
 	uint8_t *out_tmp, *src_buf, *dst_buf = NULL;
 	uint32_t dst_off = 0;
+	uint32_t last_out_len = 0;
 
 	uint8_t *key = sdcp->coh->aes_key;
 
 	int ret = 0;
 	int split = 0;
-	unsigned int i, len, clen, rem = 0;
+	unsigned int i, len, clen, rem = 0, tlen = 0;
 	int init = 0;
+	bool limit_hit = false;
 
 	actx->fill = 0;
 
@@ -316,6 +325,11 @@ static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
 	for_each_sg(req->src, src, nents, i) {
 		src_buf = sg_virt(src);
 		len = sg_dma_len(src);
+		tlen += len;
+		limit_hit = tlen > req->nbytes;
+
+		if (limit_hit)
+			len = req->nbytes - (tlen - len);
 
 		do {
 			if (actx->fill + len > out_off)
@@ -332,13 +346,15 @@ static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
 			 * If we filled the buffer or this is the last SG,
 			 * submit the buffer.
 			 */
-			if (actx->fill == out_off || sg_is_last(src)) {
+			if (actx->fill == out_off || sg_is_last(src) ||
+				limit_hit) {
 				ret = mxs_dcp_run_aes(actx, req, init);
 				if (ret)
 					return ret;
 				init = 0;
 
 				out_tmp = out_buf;
+				last_out_len = actx->fill;
 				while (dst && actx->fill) {
 					if (!split) {
 						dst_buf = sg_virt(dst);
@@ -361,6 +377,13 @@ static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
 				}
 			}
 		} while (len);
+
+		if (limit_hit)
+			break;
+	}
+	if (last_out_len >= AES_BLOCK_SIZE) {
+		memcpy(req->info, out_buf+(last_out_len-AES_BLOCK_SIZE),
+		       AES_BLOCK_SIZE);
 	}
 
 	return ret;