crypto: ccp - 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

Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Gary Hook <gary.hook@amd.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/ccp/ccp-crypto-aes-xts.c b/drivers/crypto/ccp/ccp-crypto-aes-xts.c
index 94b5bcf..ca4630b 100644 (file)
--- 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 b9fd090..28819e1 100644 (file)
--- 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;