crypto: sun4i-ss - do not allocate backup IV on requests

Instead of allocate memory on each requests, it is easier to
pre-allocate buffer for backup IV.
This made error path easier.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c
index dec79fa..10fe9f7 100644 (file)
--- a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c
+++ b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c
@@ -20,7 +20,6 @@ static int noinline_for_stack sun4i_ss_opti_poll(struct skcipher_request *areq)
        unsigned int ivsize = crypto_skcipher_ivsize(tfm);
        struct sun4i_cipher_req_ctx *ctx = skcipher_request_ctx(areq);
        u32 mode = ctx->mode;
-       void *backup_iv = NULL;
        /* when activating SS, the default FIFO space is SS_RX_DEFAULT(32) */
        u32 rx_cnt = SS_RX_DEFAULT;
        u32 tx_cnt = 0;
@@ -48,10 +47,8 @@ static int noinline_for_stack sun4i_ss_opti_poll(struct skcipher_request *areq)
        }
 
        if (areq->iv && ivsize > 0 && mode & SS_DECRYPTION) {
-               backup_iv = kzalloc(ivsize, GFP_KERNEL);
-               if (!backup_iv)
-                       return -ENOMEM;
-               scatterwalk_map_and_copy(backup_iv, areq->src, areq->cryptlen - ivsize, ivsize, 0);
+               scatterwalk_map_and_copy(ctx->backup_iv, areq->src,
+                                        areq->cryptlen - ivsize, ivsize, 0);
        }
 
        if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN4I_SS_DEBUG)) {
@@ -134,8 +131,8 @@ static int noinline_for_stack sun4i_ss_opti_poll(struct skcipher_request *areq)
 
        if (areq->iv) {
                if (mode & SS_DECRYPTION) {
-                       memcpy(areq->iv, backup_iv, ivsize);
-                       kfree_sensitive(backup_iv);
+                       memcpy(areq->iv, ctx->backup_iv, ivsize);
+                       memzero_explicit(ctx->backup_iv, ivsize);
                } else {
                        scatterwalk_map_and_copy(areq->iv, areq->dst, areq->cryptlen - ivsize,
                                                 ivsize, 0);
@@ -199,7 +196,6 @@ static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
        unsigned int ileft = areq->cryptlen;
        unsigned int oleft = areq->cryptlen;
        unsigned int todo;
-       void *backup_iv = NULL;
        struct sg_mapping_iter mi, mo;
        unsigned long pi = 0, po = 0; /* progress for in and out */
        bool miter_err;
@@ -244,10 +240,8 @@ static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
                return sun4i_ss_cipher_poll_fallback(areq);
 
        if (areq->iv && ivsize > 0 && mode & SS_DECRYPTION) {
-               backup_iv = kzalloc(ivsize, GFP_KERNEL);
-               if (!backup_iv)
-                       return -ENOMEM;
-               scatterwalk_map_and_copy(backup_iv, areq->src, areq->cryptlen - ivsize, ivsize, 0);
+               scatterwalk_map_and_copy(ctx->backup_iv, areq->src,
+                                        areq->cryptlen - ivsize, ivsize, 0);
        }
 
        if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN4I_SS_DEBUG)) {
@@ -384,8 +378,8 @@ static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
        }
        if (areq->iv) {
                if (mode & SS_DECRYPTION) {
-                       memcpy(areq->iv, backup_iv, ivsize);
-                       kfree_sensitive(backup_iv);
+                       memcpy(areq->iv, ctx->backup_iv, ivsize);
+                       memzero_explicit(ctx->backup_iv, ivsize);
                } else {
                        scatterwalk_map_and_copy(areq->iv, areq->dst, areq->cryptlen - ivsize,
                                                 ivsize, 0);

diff --git a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h
index 0fee6f4..ba59c7a 100644 (file)
--- a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h
+++ b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h
@@ -183,6 +183,7 @@ struct sun4i_tfm_ctx {
 
 struct sun4i_cipher_req_ctx {
        u32 mode;
+       u8 backup_iv[AES_BLOCK_SIZE];
        struct skcipher_request fallback_req;   // keep at the end
 };