From c776f7d37b6bf3663c838b2d2223f8ec1b523b12 Mon Sep 17 00:00:00 2001 From: Gilad Ben-Yossef Date: Thu, 18 Apr 2019 16:39:00 +0300 Subject: crypto: ccree - make AEAD sgl iterator well behaved Fix some scatter list interation code was not handling scatter lists being shorter than expected in a graceful manner. Signed-off-by: Gilad Ben-Yossef Signed-off-by: Herbert Xu --- drivers/crypto/ccree/cc_buffer_mgr.c | 55 +++++++++++------------------------- 1 file changed, 17 insertions(+), 38 deletions(-) diff --git a/drivers/crypto/ccree/cc_buffer_mgr.c b/drivers/crypto/ccree/cc_buffer_mgr.c index 86e498bee0bb..fa625bdde3f9 100644 --- a/drivers/crypto/ccree/cc_buffer_mgr.c +++ b/drivers/crypto/ccree/cc_buffer_mgr.c @@ -659,11 +659,9 @@ static int cc_aead_chain_assoc(struct cc_drvdata *drvdata, { struct aead_req_ctx *areq_ctx = aead_request_ctx(req); int rc = 0; - u32 mapped_nents = 0; - struct scatterlist *current_sg = req->src; + int mapped_nents = 0; struct crypto_aead *tfm = crypto_aead_reqtfm(req); - unsigned int sg_index = 0; - u32 size_of_assoc = areq_ctx->assoclen; + unsigned int size_of_assoc = areq_ctx->assoclen; struct device *dev = drvdata_to_dev(drvdata); if (areq_ctx->is_gcm4543) @@ -684,26 +682,10 @@ static int cc_aead_chain_assoc(struct cc_drvdata *drvdata, goto chain_assoc_exit; } - //iterate over the sgl to see how many entries are for associated data - //it is assumed that if we reach here , the sgl is already mapped - sg_index = current_sg->length; - //the first entry in the scatter list contains all the associated data - if (sg_index > size_of_assoc) { - mapped_nents++; - } else { - while (sg_index <= size_of_assoc) { - current_sg = sg_next(current_sg); - /* if have reached the end of the sgl, then this is - * unexpected - */ - if (!current_sg) { - dev_err(dev, "reached end of sg list. unexpected\n"); - return -EINVAL; - } - sg_index += current_sg->length; - mapped_nents++; - } - } + mapped_nents = sg_nents_for_len(req->src, size_of_assoc); + if (mapped_nents < 0) + return mapped_nents; + if (mapped_nents > LLI_MAX_NUM_OF_ASSOC_DATA_ENTRIES) { dev_err(dev, "Too many fragments. current %d max %d\n", mapped_nents, LLI_MAX_NUM_OF_ASSOC_DATA_ENTRIES); @@ -898,6 +880,7 @@ static int cc_aead_chain_data(struct cc_drvdata *drvdata, u32 sg_index = 0; bool is_gcm4543 = areq_ctx->is_gcm4543; u32 size_to_skip = areq_ctx->assoclen; + struct scatterlist *sgl; if (is_gcm4543) size_to_skip += crypto_aead_ivsize(tfm); @@ -920,15 +903,13 @@ static int cc_aead_chain_data(struct cc_drvdata *drvdata, sg_index = areq_ctx->src_sgl->length; //check where the data starts while (sg_index <= size_to_skip) { + src_mapped_nents--; offset -= areq_ctx->src_sgl->length; - areq_ctx->src_sgl = sg_next(areq_ctx->src_sgl); - //if have reached the end of the sgl, then this is unexpected - if (!areq_ctx->src_sgl) { - dev_err(dev, "reached end of sg list. unexpected\n"); - return -EINVAL; - } + sgl = sg_next(areq_ctx->src_sgl); + if (!sgl) + break; + areq_ctx->src_sgl = sgl; sg_index += areq_ctx->src_sgl->length; - src_mapped_nents--; } if (src_mapped_nents > LLI_MAX_NUM_OF_DATA_ENTRIES) { dev_err(dev, "Too many fragments. current %d max %d\n", @@ -962,15 +943,13 @@ static int cc_aead_chain_data(struct cc_drvdata *drvdata, //check where the data starts while (sg_index <= size_to_skip) { + dst_mapped_nents--; offset -= areq_ctx->dst_sgl->length; - areq_ctx->dst_sgl = sg_next(areq_ctx->dst_sgl); - //if have reached the end of the sgl, then this is unexpected - if (!areq_ctx->dst_sgl) { - dev_err(dev, "reached end of sg list. unexpected\n"); - return -EINVAL; - } + sgl = sg_next(areq_ctx->dst_sgl); + if (!sgl) + break; + areq_ctx->dst_sgl = sgl; sg_index += areq_ctx->dst_sgl->length; - dst_mapped_nents--; } if (dst_mapped_nents > LLI_MAX_NUM_OF_DATA_ENTRIES) { dev_err(dev, "Too many fragments. current %d max %d\n", -- cgit v1.2.3