[PATCH v3 11/12] crypto: ti - Terminate DMA on all error paths in AEAD to clear descriptors

[T Pratham]

dmaengine_prep_slave_sg() allocates a DMA descriptor which is freed on
either successful dmaengine_submit() or on dmaengine_terminate_sync().

The error paths after descriptor allocation was not clearing them,
leaving the descriptors orphaned and leaking memory in case of failure.
Add terminate calls in dthe_aead_run() to appropriately clean the DMA
descriptors.

Fixes: 37b902c603042 ("crypto: ti - Add support for AES-GCM in DTHEv2 driver")
Signed-off-by: T Pratham <t-pratham@xxxxxx>
---
 drivers/crypto/ti/dthev2-aes.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/ti/dthev2-aes.c b/drivers/crypto/ti/dthev2-aes.c
index 10073bbeca113..a034c1c8f20ed 100644
--- a/drivers/crypto/ti/dthev2-aes.c
+++ b/drivers/crypto/ti/dthev2-aes.c
@@ -912,6 +912,7 @@ static int dthe_aead_run(struct crypto_engine *engine, void *areq)
 
 	struct device *tx_dev, *rx_dev;
 	struct dma_async_tx_descriptor *desc_in, *desc_out, *desc_aad_out;
+	bool cleanup_tx_chan = false;
 
 	int ret;
 	int err;
@@ -1012,13 +1013,15 @@ static int dthe_aead_run(struct crypto_engine *engine, void *areq)
 		src_nents = sg_nents_for_len(src, cryptlen);
 		if (src_nents < 0) {
 			ret = src_nents;
-			goto aead_dma_prep_aad_err;
+			cleanup_tx_chan = (assoclen != 0);
+			goto aead_dma_map_src_err;
 		}
 		src_mapped_nents = dma_map_sg(tx_dev, src, src_nents, src_dir);
 		if (src_mapped_nents == 0) {
 			dev_err(dev_data->dev, "Failed to map ciphertext src for TX\n");
 			ret = -EINVAL;
-			goto aead_dma_prep_aad_err;
+			cleanup_tx_chan = (assoclen != 0);
+			goto aead_dma_map_src_err;
 		}
 
 		/* Prepare DMA descriptors for ciphertext TX */
@@ -1028,6 +1031,7 @@ static int dthe_aead_run(struct crypto_engine *engine, void *areq)
 		if (!desc_out) {
 			dev_err(dev_data->dev, "Ciphertext TX prep_slave_sg() failed\n");
 			ret = -EINVAL;
+			cleanup_tx_chan = (assoclen != 0);
 			goto aead_dma_prep_src_err;
 		}
 
@@ -1036,12 +1040,14 @@ static int dthe_aead_run(struct crypto_engine *engine, void *areq)
 			dst_nents = sg_nents_for_len(dst, cryptlen);
 			if (dst_nents < 0) {
 				ret = dst_nents;
+				cleanup_tx_chan = true;
 				goto aead_dma_prep_src_err;
 			}
 			dst_mapped_nents = dma_map_sg(rx_dev, dst, dst_nents, dst_dir);
 			if (dst_mapped_nents == 0) {
 				dev_err(dev_data->dev, "Failed to map ciphertext dst for RX\n");
 				ret = -EINVAL;
+				cleanup_tx_chan = true;
 				goto aead_dma_prep_src_err;
 			}
 		} else {
@@ -1056,6 +1062,7 @@ static int dthe_aead_run(struct crypto_engine *engine, void *areq)
 		if (!desc_in) {
 			dev_err(dev_data->dev, "Ciphertext RX prep_slave_sg() failed\n");
 			ret = -EINVAL;
+			cleanup_tx_chan = true;
 			goto aead_dma_prep_dst_err;
 		}
 
@@ -1145,6 +1152,10 @@ static int dthe_aead_run(struct crypto_engine *engine, void *areq)
 aead_dma_prep_src_err:
 	if (cryptlen != 0)
 		dma_unmap_sg(tx_dev, src, src_nents, src_dir);
+aead_dma_map_src_err:
+	/* Free any descriptor prepared on dma_aes_tx but never submitted */
+	if (cleanup_tx_chan)
+		dmaengine_terminate_sync(dev_data->dma_aes_tx);
 aead_dma_prep_aad_err:
 	if (assoclen != 0)
 		dma_unmap_sg(tx_dev, aad_sg, aad_nents, aad_dir);
-- 
2.34.1