Quoting Nikita Zhandarovich (2023-12-01 13:49:29)
> Macro dma_map_sg() may return 0 on error. This patch enables
> checks in case of the macro failure and ensures unmapping of
> previously mapped buffers with dma_unmap_sg().
>
> Found by Linux Verification Center (linuxtesting.org) with static
> analysis tool SVACE.
>
> Fixes: 49186a7d9e46 ("crypto: inside_secure - Avoid dma map if size is zero")
> Signed-off-by: Nikita Zhandarovich <n.zhandarovich@xxxxxxxxxx>
Reviewed-by: Antoine Tenart <atenart@xxxxxxxxxx>
Thanks!
Antoine
> ---
> v2: remove extra level of parentheses and
> change return error code from -ENOMEM to EIO
> per Antoine Tenart's <atenart@xxxxxxxxxx> suggestion
>
> drivers/crypto/inside-secure/safexcel_cipher.c | 19 +++++++++++--------
> 1 file changed, 11 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/crypto/inside-secure/safexcel_cipher.c b/drivers/crypto/inside-secure/safexcel_cipher.c
> index 272c28b5a088..b83818634ae4 100644
> --- a/drivers/crypto/inside-secure/safexcel_cipher.c
> +++ b/drivers/crypto/inside-secure/safexcel_cipher.c
> @@ -742,9 +742,9 @@ static int safexcel_send_req(struct crypto_async_request *base, int ring,
> max(totlen_src, totlen_dst));
> return -EINVAL;
> }
> - if (sreq->nr_src > 0)
> - dma_map_sg(priv->dev, src, sreq->nr_src,
> - DMA_BIDIRECTIONAL);
> + if (sreq->nr_src > 0 &&
> + !dma_map_sg(priv->dev, src, sreq->nr_src, DMA_BIDIRECTIONAL))
> + return -EIO;
> } else {
> if (unlikely(totlen_src && (sreq->nr_src <= 0))) {
> dev_err(priv->dev, "Source buffer not large enough (need %d bytes)!",
> @@ -752,8 +752,9 @@ static int safexcel_send_req(struct crypto_async_request *base, int ring,
> return -EINVAL;
> }
>
> - if (sreq->nr_src > 0)
> - dma_map_sg(priv->dev, src, sreq->nr_src, DMA_TO_DEVICE);
> + if (sreq->nr_src > 0 &&
> + !dma_map_sg(priv->dev, src, sreq->nr_src, DMA_TO_DEVICE))
> + return -EIO;
>
> if (unlikely(totlen_dst && (sreq->nr_dst <= 0))) {
> dev_err(priv->dev, "Dest buffer not large enough (need %d bytes)!",
> @@ -762,9 +763,11 @@ static int safexcel_send_req(struct crypto_async_request *base, int ring,
> goto unmap;
> }
>
> - if (sreq->nr_dst > 0)
> - dma_map_sg(priv->dev, dst, sreq->nr_dst,
> - DMA_FROM_DEVICE);
> + if (sreq->nr_dst > 0 &&
> + !dma_map_sg(priv->dev, dst, sreq->nr_dst, DMA_FROM_DEVICE)) {
> + ret = -EIO;
> + goto unmap;
> + }
> }
>
> memcpy(ctx->base.ctxr->data, ctx->key, ctx->key_len);
>
