From 3ee50c896d712dc2fc8f34c2cd1918d035e74045 Mon Sep 17 00:00:00 2001 From: Eneas U de Queiroz Date: Fri, 20 Dec 2019 16:02:15 -0300 Subject: [PATCH] crypto: qce - save a sg table slot for result buf When ctr-aes-qce is used for gcm-mode, an extra sg entry for the authentication tag is present, causing trouble when the qce driver prepares the dst-results sg table for dma. It computes the number of entries needed with sg_nents_for_len, leaving out the tag entry. Then it creates a sg table with that number plus one, used to store a result buffer. When copying the sg table, there's no limit to the number of entries copied, so the extra slot is filled with the authentication tag sg. When the driver tries to add the result sg, the list is full, and it returns EINVAL. By limiting the number of sg entries copied to the dest table, the slot for the result buffer is guaranteed to be unused. Signed-off-by: Eneas U de Queiroz Signed-off-by: Herbert Xu --- drivers/crypto/qce/dma.c | 6 ++++-- drivers/crypto/qce/dma.h | 3 ++- drivers/crypto/qce/skcipher.c | 4 ++-- 3 files changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/crypto/qce/dma.c b/drivers/crypto/qce/dma.c index 40a5921..7da893d 100644 --- a/drivers/crypto/qce/dma.c +++ b/drivers/crypto/qce/dma.c @@ -47,7 +47,8 @@ void qce_dma_release(struct qce_dma_data *dma) } struct scatterlist * -qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl) +qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl, + int max_ents) { struct scatterlist *sg = sgt->sgl, *sg_last = NULL; @@ -60,12 +61,13 @@ qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl) if (!sg) return ERR_PTR(-EINVAL); - while (new_sgl && sg) { + while (new_sgl && sg && max_ents) { sg_set_page(sg, sg_page(new_sgl), new_sgl->length, new_sgl->offset); sg_last = sg; sg = sg_next(sg); new_sgl = sg_next(new_sgl); + max_ents--; } return sg_last; diff --git a/drivers/crypto/qce/dma.h b/drivers/crypto/qce/dma.h index 1e25a9e..ed25a0d 100644 --- a/drivers/crypto/qce/dma.h +++ b/drivers/crypto/qce/dma.h @@ -42,6 +42,7 @@ int qce_dma_prep_sgs(struct qce_dma_data *dma, struct scatterlist *sg_in, void qce_dma_issue_pending(struct qce_dma_data *dma); int qce_dma_terminate_all(struct qce_dma_data *dma); struct scatterlist * -qce_sgtable_add(struct sg_table *sgt, struct scatterlist *sg_add); +qce_sgtable_add(struct sg_table *sgt, struct scatterlist *sg_add, + int max_ents); #endif /* _DMA_H_ */ diff --git a/drivers/crypto/qce/skcipher.c b/drivers/crypto/qce/skcipher.c index e4f6d87..a9ae356 100644 --- a/drivers/crypto/qce/skcipher.c +++ b/drivers/crypto/qce/skcipher.c @@ -95,13 +95,13 @@ qce_skcipher_async_req_handle(struct crypto_async_request *async_req) sg_init_one(&rctx->result_sg, qce->dma.result_buf, QCE_RESULT_BUF_SZ); - sg = qce_sgtable_add(&rctx->dst_tbl, req->dst); + sg = qce_sgtable_add(&rctx->dst_tbl, req->dst, rctx->dst_nents - 1); if (IS_ERR(sg)) { ret = PTR_ERR(sg); goto error_free; } - sg = qce_sgtable_add(&rctx->dst_tbl, &rctx->result_sg); + sg = qce_sgtable_add(&rctx->dst_tbl, &rctx->result_sg, 1); if (IS_ERR(sg)) { ret = PTR_ERR(sg); goto error_free; -- 2.7.4