From f805f59d1ea2f599516e183d753e4e0acc2ed721 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 18 Sep 2018 19:10:57 -0700 Subject: crypto: mxs-dcp - Remove VLA usage of skcipher In the quest to remove all stack VLA usage from the kernel[1], this replaces struct crypto_skcipher and SKCIPHER_REQUEST_ON_STACK() usage with struct crypto_sync_skcipher and SYNC_SKCIPHER_REQUEST_ON_STACK(), which uses a fixed stack size. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Signed-off-by: Kees Cook Signed-off-by: Herbert Xu --- drivers/crypto/mxs-dcp.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) (limited to 'drivers/crypto') diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c index a10c418d4e5c..430174be6f92 100644 --- a/drivers/crypto/mxs-dcp.c +++ b/drivers/crypto/mxs-dcp.c @@ -84,7 +84,7 @@ struct dcp_async_ctx { unsigned int hot:1; /* Crypto-specific context */ - struct crypto_skcipher *fallback; + struct crypto_sync_skcipher *fallback; unsigned int key_len; uint8_t key[AES_KEYSIZE_128]; }; @@ -376,10 +376,10 @@ static int mxs_dcp_block_fallback(struct ablkcipher_request *req, int enc) { struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req); struct dcp_async_ctx *ctx = crypto_ablkcipher_ctx(tfm); - SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback); + SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback); int ret; - skcipher_request_set_tfm(subreq, ctx->fallback); + skcipher_request_set_sync_tfm(subreq, ctx->fallback); skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL); skcipher_request_set_crypt(subreq, req->src, req->dst, req->nbytes, req->info); @@ -460,16 +460,16 @@ static int mxs_dcp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key, * but is supported by in-kernel software implementation, we use * software fallback. */ - crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); - crypto_skcipher_set_flags(actx->fallback, + crypto_sync_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); + crypto_sync_skcipher_set_flags(actx->fallback, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); - ret = crypto_skcipher_setkey(actx->fallback, key, len); + ret = crypto_sync_skcipher_setkey(actx->fallback, key, len); if (!ret) return 0; tfm->base.crt_flags &= ~CRYPTO_TFM_RES_MASK; - tfm->base.crt_flags |= crypto_skcipher_get_flags(actx->fallback) & + tfm->base.crt_flags |= crypto_sync_skcipher_get_flags(actx->fallback) & CRYPTO_TFM_RES_MASK; return ret; @@ -478,11 +478,10 @@ static int mxs_dcp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key, static int mxs_dcp_aes_fallback_init(struct crypto_tfm *tfm) { const char *name = crypto_tfm_alg_name(tfm); - const uint32_t flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK; struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm); - struct crypto_skcipher *blk; + struct crypto_sync_skcipher *blk; - blk = crypto_alloc_skcipher(name, 0, flags); + blk = crypto_alloc_sync_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(blk)) return PTR_ERR(blk); @@ -495,7 +494,7 @@ static void mxs_dcp_aes_fallback_exit(struct crypto_tfm *tfm) { struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm); - crypto_free_skcipher(actx->fallback); + crypto_free_sync_skcipher(actx->fallback); } /* -- cgit v1.2.3-59-g8ed1b