On Tue, Aug 3, 2021 at 2:25 AM Corentin Labbe [off-list ref] wrote:

Le Mon, Jul 26, 2021 at 11:27:12PM +0800, Dongliang Mu a écrit :

quoted

In sun8i_ce_hash_run, all the dma_mmap_sg/single will cause memory leak
due to no corresponding unmap operation if errors happen.

Fix this by adding error handling part for all the dma_mmap_sg/single.

I think it could be better worded, error handling is already there (but bad).

Sure. How about "Fix this by freeing the objects allocated by
dma_mmap_sg/single when errors occur."?

quoted

Fixes: 56f6d5aee88d ("crypto: sun8i-ce - support hash algorithms")
Signed-off-by: Dongliang Mu <redacted>
---
 .../crypto/allwinner/sun8i-ce/sun8i-ce-hash.c | 28 +++++++++----------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-hash.c b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-hash.c
index 88194718a806..d454ad99deee 100644
--- a/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-hash.c
+++ b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-hash.c

@@ -286,16 +286,14 @@ int sun8i_ce_hash_run(struct crypto_engine *engine, void *breq)

      /* the padding could be up to two block. */
      buf = kzalloc(bs * 2, GFP_KERNEL | GFP_DMA);
-     if (!buf) {
-             err = -ENOMEM;
-             goto theend;

Please keep all goto error for being consistent.

OK, no problem.

BTW, usually for the 1st malloc failure, I prefer returning with errno directly.

quoted

-     }
+     if (!buf)
+             return -ENOMEM;
      bf = (__le32 *)buf;

      result = kzalloc(digestsize, GFP_KERNEL | GFP_DMA);
      if (!result) {
-             err = -ENOMEM;
-             goto theend;
+             kfree(buf);
+             return -ENOMEM;
      }

      flow = rctx->flow;

@@ -321,7 +319,7 @@ int sun8i_ce_hash_run(struct crypto_engine *engine, void *breq)
      if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
              dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
              err = -EINVAL;
-             goto theend;
+             goto err_result;
      }

      len = areq->nbytes;

@@ -334,7 +332,7 @@ int sun8i_ce_hash_run(struct crypto_engine *engine, void *breq)
      if (len > 0) {
              dev_err(ce->dev, "remaining len %d\n", len);
              err = -EINVAL;
-             goto theend;
+             goto err_unmap_sg;
      }
      addr_res = dma_map_single(ce->dev, result, digestsize, DMA_FROM_DEVICE);
      cet->t_dst[0].addr = cpu_to_le32(addr_res);

@@ -342,7 +340,7 @@ int sun8i_ce_hash_run(struct crypto_engine *engine, void *breq)
      if (dma_mapping_error(ce->dev, addr_res)) {
              dev_err(ce->dev, "DMA map dest\n");
              err = -EINVAL;
-             goto theend;
+             goto err_unmap_sg;
      }

      byte_count = areq->nbytes;

@@ -392,7 +390,7 @@ int sun8i_ce_hash_run(struct crypto_engine *engine, void *breq)
      if (dma_mapping_error(ce->dev, addr_pad)) {
              dev_err(ce->dev, "DMA error on padding SG\n");
              err = -EINVAL;
-             goto theend;
+             goto err_addr_res;
      }

      if (ce->variant->hash_t_dlen_in_bits)

@@ -405,15 +403,15 @@ int sun8i_ce_hash_run(struct crypto_engine *engine, void *breq)
      err = sun8i_ce_run_task(ce, flow, crypto_tfm_alg_name(areq->base.tfm));

      dma_unmap_single(ce->dev, addr_pad, j * 4, DMA_TO_DEVICE);
+err_addr_res:
+     dma_unmap_single(ce->dev, addr_res, digestsize, DMA_FROM_DEVICE);
+err_unmap_sg:
      dma_unmap_sg(ce->dev, areq->src, sg_nents(areq->src),
                   DMA_TO_DEVICE);
-     dma_unmap_single(ce->dev, addr_res, digestsize, DMA_FROM_DEVICE);
-
-
      memcpy(areq->result, result, algt->alg.hash.halg.digestsize);

The result should be copied only when everything is ok. Please add a "if (!err)"

Sure.

Thanks for your work
Regards

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