We were handling chained scattergather lists with specialized code needlessly as the regular sg APIs handle them just fine. The code handling this also had an (unused) code path with a use-before-init error, flagged by Coverity.
Remove all special handling of chained sg and leave their handling to the regular sg APIs.
Signed-off-by: Gilad Ben-Yossef gilad@benyossef.com Cc: stable@vger.kernel.org # v4.19+ --- drivers/crypto/ccree/cc_buffer_mgr.c | 98 +++++++--------------------- 1 file changed, 22 insertions(+), 76 deletions(-)
diff --git a/drivers/crypto/ccree/cc_buffer_mgr.c b/drivers/crypto/ccree/cc_buffer_mgr.c index adef3cfa1251..7c92373df351 100644 --- a/drivers/crypto/ccree/cc_buffer_mgr.c +++ b/drivers/crypto/ccree/cc_buffer_mgr.c @@ -83,24 +83,17 @@ static void cc_copy_mac(struct device *dev, struct aead_request *req, */ static unsigned int cc_get_sgl_nents(struct device *dev, struct scatterlist *sg_list, - unsigned int nbytes, u32 *lbytes, - bool *is_chained) + unsigned int nbytes, u32 *lbytes) { unsigned int nents = 0;
while (nbytes && sg_list) { - if (sg_list->length) { - nents++; - /* get the number of bytes in the last entry */ - *lbytes = nbytes; - nbytes -= (sg_list->length > nbytes) ? - nbytes : sg_list->length; - sg_list = sg_next(sg_list); - } else { - sg_list = (struct scatterlist *)sg_page(sg_list); - if (is_chained) - *is_chained = true; - } + nents++; + /* get the number of bytes in the last entry */ + *lbytes = nbytes; + nbytes -= (sg_list->length > nbytes) ? + nbytes : sg_list->length; + sg_list = sg_next(sg_list); } dev_dbg(dev, "nents %d last bytes %d\n", nents, *lbytes); return nents; @@ -142,7 +135,7 @@ void cc_copy_sg_portion(struct device *dev, u8 *dest, struct scatterlist *sg, { u32 nents, lbytes;
- nents = cc_get_sgl_nents(dev, sg, end, &lbytes, NULL); + nents = cc_get_sgl_nents(dev, sg, end, &lbytes); sg_copy_buffer(sg, nents, (void *)dest, (end - to_skip + 1), to_skip, (direct == CC_SG_TO_BUF)); } @@ -314,40 +307,10 @@ static void cc_add_sg_entry(struct device *dev, struct buffer_array *sgl_data, sgl_data->num_of_buffers++; }
-static int cc_dma_map_sg(struct device *dev, struct scatterlist *sg, u32 nents, - enum dma_data_direction direction) -{ - u32 i, j; - struct scatterlist *l_sg = sg; - - for (i = 0; i < nents; i++) { - if (!l_sg) - break; - if (dma_map_sg(dev, l_sg, 1, direction) != 1) { - dev_err(dev, "dma_map_page() sg buffer failed\n"); - goto err; - } - l_sg = sg_next(l_sg); - } - return nents; - -err: - /* Restore mapped parts */ - for (j = 0; j < i; j++) { - if (!sg) - break; - dma_unmap_sg(dev, sg, 1, direction); - sg = sg_next(sg); - } - return 0; -} - static int cc_map_sg(struct device *dev, struct scatterlist *sg, unsigned int nbytes, int direction, u32 *nents, u32 max_sg_nents, u32 *lbytes, u32 *mapped_nents) { - bool is_chained = false; - if (sg_is_last(sg)) { /* One entry only case -set to DLLI */ if (dma_map_sg(dev, sg, 1, direction) != 1) { @@ -361,35 +324,21 @@ static int cc_map_sg(struct device *dev, struct scatterlist *sg, *nents = 1; *mapped_nents = 1; } else { /*sg_is_last*/ - *nents = cc_get_sgl_nents(dev, sg, nbytes, lbytes, - &is_chained); + *nents = cc_get_sgl_nents(dev, sg, nbytes, lbytes); if (*nents > max_sg_nents) { *nents = 0; dev_err(dev, "Too many fragments. current %d max %d\n", *nents, max_sg_nents); return -ENOMEM; } - if (!is_chained) { - /* In case of mmu the number of mapped nents might - * be changed from the original sgl nents - */ - *mapped_nents = dma_map_sg(dev, sg, *nents, direction); - if (*mapped_nents == 0) { - *nents = 0; - dev_err(dev, "dma_map_sg() sg buffer failed\n"); - return -ENOMEM; - } - } else { - /*In this case the driver maps entry by entry so it - * must have the same nents before and after map - */ - *mapped_nents = cc_dma_map_sg(dev, sg, *nents, - direction); - if (*mapped_nents != *nents) { - *nents = *mapped_nents; - dev_err(dev, "dma_map_sg() sg buffer failed\n"); - return -ENOMEM; - } + /* In case of mmu the number of mapped nents might + * be changed from the original sgl nents + */ + *mapped_nents = dma_map_sg(dev, sg, *nents, direction); + if (*mapped_nents == 0) { + *nents = 0; + dev_err(dev, "dma_map_sg() sg buffer failed\n"); + return -ENOMEM; } }
@@ -571,7 +520,6 @@ void cc_unmap_aead_request(struct device *dev, struct aead_request *req) struct crypto_aead *tfm = crypto_aead_reqtfm(req); struct cc_drvdata *drvdata = dev_get_drvdata(dev); u32 dummy; - bool chained; u32 size_to_unmap = 0;
if (areq_ctx->mac_buf_dma_addr) { @@ -636,15 +584,14 @@ void cc_unmap_aead_request(struct device *dev, struct aead_request *req) size_to_unmap += crypto_aead_ivsize(tfm);
dma_unmap_sg(dev, req->src, - cc_get_sgl_nents(dev, req->src, size_to_unmap, - &dummy, &chained), + cc_get_sgl_nents(dev, req->src, size_to_unmap, &dummy), DMA_BIDIRECTIONAL); if (req->src != req->dst) { dev_dbg(dev, "Unmapping dst sgl: req->dst=%pK\n", sg_virt(req->dst)); dma_unmap_sg(dev, req->dst, cc_get_sgl_nents(dev, req->dst, size_to_unmap, - &dummy, &chained), + &dummy), DMA_BIDIRECTIONAL); } if (drvdata->coherent && @@ -1022,7 +969,6 @@ static int cc_aead_chain_data(struct cc_drvdata *drvdata, unsigned int size_for_map = req->assoclen + req->cryptlen; struct crypto_aead *tfm = crypto_aead_reqtfm(req); u32 sg_index = 0; - bool chained = false; bool is_gcm4543 = areq_ctx->is_gcm4543; u32 size_to_skip = req->assoclen;
@@ -1043,7 +989,7 @@ static int cc_aead_chain_data(struct cc_drvdata *drvdata, size_for_map += (direct == DRV_CRYPTO_DIRECTION_ENCRYPT) ? authsize : 0; src_mapped_nents = cc_get_sgl_nents(dev, req->src, size_for_map, - &src_last_bytes, &chained); + &src_last_bytes); sg_index = areq_ctx->src_sgl->length; //check where the data starts while (sg_index <= size_to_skip) { @@ -1083,7 +1029,7 @@ static int cc_aead_chain_data(struct cc_drvdata *drvdata, }
dst_mapped_nents = cc_get_sgl_nents(dev, req->dst, size_for_map, - &dst_last_bytes, &chained); + &dst_last_bytes); sg_index = areq_ctx->dst_sgl->length; offset = size_to_skip;
@@ -1484,7 +1430,7 @@ int cc_map_hash_request_update(struct cc_drvdata *drvdata, void *ctx, dev_dbg(dev, " less than one block: curr_buff=%pK *curr_buff_cnt=0x%X copy_to=%pK\n", curr_buff, *curr_buff_cnt, &curr_buff[*curr_buff_cnt]); areq_ctx->in_nents = - cc_get_sgl_nents(dev, src, nbytes, &dummy, NULL); + cc_get_sgl_nents(dev, src, nbytes, &dummy); sg_copy_to_buffer(src, areq_ctx->in_nents, &curr_buff[*curr_buff_cnt], nbytes); *curr_buff_cnt += nbytes;