On Fri, May 06, 2022 at 03:38:59PM +0100, Giovanni Cabiddu wrote:

Set to zero the DH context buffers containing the DH key before they are freed. This is to make sure keys are not leaked out by a subsequent memory allocation.

Cc: stable@vger.kernel.org Fixes: c9839143ebbf ("crypto: qat - Add DH support") Signed-off-by: Giovanni Cabiddu giovanni.cabiddu@intel.com Reviewed-by: Adam Guerin adam.guerin@intel.com Reviewed-by: Wojciech Ziemba wojciech.ziemba@intel.com

---

drivers/crypto/qat/qat_common/qat_asym_algs.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/drivers/crypto/qat/qat_common/qat_asym_algs.c b/drivers/crypto/qat/qat_common/qat_asym_algs.c index d75eb77c9fb9..25bbd22085c3 100644 --- a/drivers/crypto/qat/qat_common/qat_asym_algs.c +++ b/drivers/crypto/qat/qat_common/qat_asym_algs.c @@ -421,14 +421,17 @@ static int qat_dh_set_params(struct qat_dh_ctx *ctx, struct dh *params) static void qat_dh_clear_ctx(struct device *dev, struct qat_dh_ctx *ctx) { if (ctx->g) {

• memset(ctx->g, 0, ctx->p_size);
  

  dma_free_coherent(dev, ctx->p_size, ctx->g, ctx->dma_g); ctx->g = NULL; } if (ctx->xa) {

• memset(ctx->xa, 0, ctx->p_size);
  

  dma_free_coherent(dev, ctx->p_size, ctx->xa, ctx->dma_xa); ctx->xa = NULL; } if (ctx->p) {

• memset(ctx->p, 0, ctx->p_size);
  

  dma_free_coherent(dev, ctx->p_size, ctx->p, ctx->dma_p); ctx->p = NULL; }

-- 2.35.1

As I just wrote, I do not think you need this. If you do, please explain what you are trying to protect the kernel from here. Itself?

thanks,

greg k-h