From: Giovanni Cabiddu giovanni.cabiddu@intel.com
[ Upstream commit 1731160ff7c7bbb11bb1aacb14dd25e18d522779 ]
Set to zero the context buffers containing the DH key before they are freed. This is a defense in depth measure that avoids keys to be recovered from memory in case the system is compromised between the free of the buffer and when that area of memory (containing keys) gets overwritten.
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 Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Sasha Levin sashal@kernel.org --- 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 b0b78445418b..5633f9df3b6f 100644 --- a/drivers/crypto/qat/qat_common/qat_asym_algs.c +++ b/drivers/crypto/qat/qat_common/qat_asym_algs.c @@ -420,14 +420,17 @@ 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; }