From: Kees Cook Subject: [PATCH crypto-next 12/23] crypto: ccp - Remove VLA usage of skcipher Date: Tue, 18 Sep 2018 19:10:49 -0700 Message-ID: <20180919021100.3380-13-keescook@chromium.org> References: <20180919021100.3380-1-keescook@chromium.org> Cc: Kees Cook , Tom Lendacky , Gary Hook , Ard Biesheuvel , Eric Biggers , linux-crypto , Linux Kernel Mailing List To: Herbert Xu Return-path: In-Reply-To: <20180919021100.3380-1-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org 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 Cc: Tom Lendacky Cc: Gary Hook Signed-off-by: Kees Cook --- drivers/crypto/ccp/ccp-crypto-aes-xts.c | 13 +++++++------ drivers/crypto/ccp/ccp-crypto.h | 2 +- 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/crypto/ccp/ccp-crypto-aes-xts.c b/drivers/crypto/ccp/ccp-crypto-aes-xts.c index 94b5bcf5b628..ca4630b8395f 100644 --- a/drivers/crypto/ccp/ccp-crypto-aes-xts.c +++ b/drivers/crypto/ccp/ccp-crypto-aes-xts.c @@ -102,7 +102,7 @@ static int ccp_aes_xts_setkey(struct crypto_ablkcipher *tfm, const u8 *key, ctx->u.aes.key_len = key_len / 2; sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len); - return crypto_skcipher_setkey(ctx->u.aes.tfm_skcipher, key, key_len); + return crypto_sync_skcipher_setkey(ctx->u.aes.tfm_skcipher, key, key_len); } static int ccp_aes_xts_crypt(struct ablkcipher_request *req, @@ -151,12 +151,13 @@ static int ccp_aes_xts_crypt(struct ablkcipher_request *req, (ctx->u.aes.key_len != AES_KEYSIZE_256)) fallback = 1; if (fallback) { - SKCIPHER_REQUEST_ON_STACK(subreq, ctx->u.aes.tfm_skcipher); + SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, + ctx->u.aes.tfm_skcipher); /* Use the fallback to process the request for any * unsupported unit sizes or key sizes */ - skcipher_request_set_tfm(subreq, ctx->u.aes.tfm_skcipher); + skcipher_request_set_sync_tfm(subreq, ctx->u.aes.tfm_skcipher); skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL); skcipher_request_set_crypt(subreq, req->src, req->dst, @@ -203,12 +204,12 @@ static int ccp_aes_xts_decrypt(struct ablkcipher_request *req) static int ccp_aes_xts_cra_init(struct crypto_tfm *tfm) { struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); - struct crypto_skcipher *fallback_tfm; + struct crypto_sync_skcipher *fallback_tfm; ctx->complete = ccp_aes_xts_complete; ctx->u.aes.key_len = 0; - fallback_tfm = crypto_alloc_skcipher("xts(aes)", 0, + fallback_tfm = crypto_alloc_sync_skcipher("xts(aes)", 0, CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(fallback_tfm)) { @@ -226,7 +227,7 @@ static void ccp_aes_xts_cra_exit(struct crypto_tfm *tfm) { struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); - crypto_free_skcipher(ctx->u.aes.tfm_skcipher); + crypto_free_sync_skcipher(ctx->u.aes.tfm_skcipher); } static int ccp_register_aes_xts_alg(struct list_head *head, diff --git a/drivers/crypto/ccp/ccp-crypto.h b/drivers/crypto/ccp/ccp-crypto.h index b9fd090c46c2..28819e11db96 100644 --- a/drivers/crypto/ccp/ccp-crypto.h +++ b/drivers/crypto/ccp/ccp-crypto.h @@ -88,7 +88,7 @@ static inline struct ccp_crypto_ahash_alg * /***** AES related defines *****/ struct ccp_aes_ctx { /* Fallback cipher for XTS with unsupported unit sizes */ - struct crypto_skcipher *tfm_skcipher; + struct crypto_sync_skcipher *tfm_skcipher; /* Cipher used to generate CMAC K1/K2 keys */ struct crypto_cipher *tfm_cipher; -- 2.17.1