From 874e163759f27e0a9988c5d1f4605e3f25564fd2 Mon Sep 17 00:00:00 2001 From: Gilad Ben-Yossef Date: Thu, 18 Apr 2019 16:39:04 +0300 Subject: [PATCH] crypto: ccree - don't map MAC key on stack The MAC hash key might be passed to us on stack. Copy it to a slab buffer before mapping to gurantee proper DMA mapping. Signed-off-by: Gilad Ben-Yossef Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu --- drivers/crypto/ccree/cc_hash.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/drivers/crypto/ccree/cc_hash.c b/drivers/crypto/ccree/cc_hash.c index 36e9fb4141f8..a6abe4e3bb0e 100644 --- a/drivers/crypto/ccree/cc_hash.c +++ b/drivers/crypto/ccree/cc_hash.c @@ -69,6 +69,7 @@ struct cc_hash_alg { struct hash_key_req_ctx { u32 keylen; dma_addr_t key_dma_addr; + u8 *key; }; /* hash per-session context */ @@ -742,13 +743,20 @@ static int cc_hash_setkey(struct crypto_ahash *ahash, const u8 *key, ctx->key_params.keylen = keylen; ctx->key_params.key_dma_addr = 0; ctx->is_hmac = true; + ctx->key_params.key = NULL; if (keylen) { + ctx->key_params.key = kmemdup(key, keylen, GFP_KERNEL); + if (!ctx->key_params.key) + return -ENOMEM; + ctx->key_params.key_dma_addr = - dma_map_single(dev, (void *)key, keylen, DMA_TO_DEVICE); + dma_map_single(dev, (void *)ctx->key_params.key, keylen, + DMA_TO_DEVICE); if (dma_mapping_error(dev, ctx->key_params.key_dma_addr)) { dev_err(dev, "Mapping key va=0x%p len=%u for DMA failed\n", - key, keylen); + ctx->key_params.key, keylen); + kzfree(ctx->key_params.key); return -ENOMEM; } dev_dbg(dev, "mapping key-buffer: key_dma_addr=%pad keylen=%u\n", @@ -899,6 +907,9 @@ out: dev_dbg(dev, "Unmapped key-buffer: key_dma_addr=%pad keylen=%u\n", &ctx->key_params.key_dma_addr, ctx->key_params.keylen); } + + kzfree(ctx->key_params.key); + return rc; } @@ -925,11 +936,16 @@ static int cc_xcbc_setkey(struct crypto_ahash *ahash, ctx->key_params.keylen = keylen; + ctx->key_params.key = kmemdup(key, keylen, GFP_KERNEL); + if (!ctx->key_params.key) + return -ENOMEM; + ctx->key_params.key_dma_addr = - dma_map_single(dev, (void *)key, keylen, DMA_TO_DEVICE); + dma_map_single(dev, ctx->key_params.key, keylen, DMA_TO_DEVICE); if (dma_mapping_error(dev, ctx->key_params.key_dma_addr)) { dev_err(dev, "Mapping key va=0x%p len=%u for DMA failed\n", key, keylen); + kzfree(ctx->key_params.key); return -ENOMEM; } dev_dbg(dev, "mapping key-buffer: key_dma_addr=%pad keylen=%u\n", @@ -981,6 +997,8 @@ static int cc_xcbc_setkey(struct crypto_ahash *ahash, dev_dbg(dev, "Unmapped key-buffer: key_dma_addr=%pad keylen=%u\n", &ctx->key_params.key_dma_addr, ctx->key_params.keylen); + kzfree(ctx->key_params.key); + return rc; } -- 2.30.2