crypto: skcipher - Make skcipher_walk src.virt.addr const

Mark the src.virt.addr field in struct skcipher_walk as a pointer
to const data.  This guarantees that the user won't modify the data
which should be done through dst.virt.addr to ensure that flushing
is done when necessary.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

5 files changed, 22 insertions, 22 deletions

diff --git a/crypto/ctr.c b/crypto/ctr.c
index 73c0d6e53b2f..97a947b0a876 100644
--- a/crypto/ctr.c
+++ b/crypto/ctr.c
@@ -33,7 +33,7 @@ static void crypto_ctr_crypt_final(struct skcipher_walk *walk,
 	u8 *ctrblk = walk->iv;
 	u8 tmp[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
 	u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1);
-	u8 *src = walk->src.virt.addr;
+	const u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	unsigned int nbytes = walk->nbytes;
 
@@ -50,7 +50,7 @@ static int crypto_ctr_crypt_segment(struct skcipher_walk *walk,
 		   crypto_cipher_alg(tfm)->cia_encrypt;
 	unsigned int bsize = crypto_cipher_blocksize(tfm);
 	u8 *ctrblk = walk->iv;
-	u8 *src = walk->src.virt.addr;
+	const u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	unsigned int nbytes = walk->nbytes;
 
@@ -77,20 +77,20 @@ static int crypto_ctr_crypt_inplace(struct skcipher_walk *walk,
 	unsigned int bsize = crypto_cipher_blocksize(tfm);
 	unsigned long alignmask = crypto_cipher_alignmask(tfm);
 	unsigned int nbytes = walk->nbytes;
+	u8 *dst = walk->dst.virt.addr;
 	u8 *ctrblk = walk->iv;
-	u8 *src = walk->src.virt.addr;
 	u8 tmp[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
 	u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1);
 
 	do {
 		/* create keystream */
 		fn(crypto_cipher_tfm(tfm), keystream, ctrblk);
-		crypto_xor(src, keystream, bsize);
+		crypto_xor(dst, keystream, bsize);
 
 		/* increment counter in counterblock */
 		crypto_inc(ctrblk, bsize);
 
-		src += bsize;
+		dst += bsize;
 	} while ((nbytes -= bsize) >= bsize);
 
 	return nbytes;
diff --git a/crypto/lrw.c b/crypto/lrw.c
index e216fbf2b786..391ae0f7641f 100644
--- a/crypto/lrw.c
+++ b/crypto/lrw.c
@@ -167,7 +167,7 @@ static int lrw_xor_tweak(struct skcipher_request *req, bool second_pass)
 
 	while (w.nbytes) {
 		unsigned int avail = w.nbytes;
-		be128 *wsrc;
+		const be128 *wsrc;
 		be128 *wdst;
 
 		wsrc = w.src.virt.addr;
diff --git a/crypto/pcbc.c b/crypto/pcbc.c
index cbfb3ac14b3a..9d2e56d6744a 100644
--- a/crypto/pcbc.c
+++ b/crypto/pcbc.c
@@ -22,8 +22,8 @@ static int crypto_pcbc_encrypt_segment(struct skcipher_request *req,
 				       struct crypto_cipher *tfm)
 {
 	int bsize = crypto_cipher_blocksize(tfm);
+	const u8 *src = walk->src.virt.addr;
 	unsigned int nbytes = walk->nbytes;
-	u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	u8 * const iv = walk->iv;
 
@@ -45,17 +45,17 @@ static int crypto_pcbc_encrypt_inplace(struct skcipher_request *req,
 {
 	int bsize = crypto_cipher_blocksize(tfm);
 	unsigned int nbytes = walk->nbytes;
-	u8 *src = walk->src.virt.addr;
+	u8 *dst = walk->dst.virt.addr;
 	u8 * const iv = walk->iv;
 	u8 tmpbuf[MAX_CIPHER_BLOCKSIZE];
 
 	do {
-		memcpy(tmpbuf, src, bsize);
-		crypto_xor(iv, src, bsize);
-		crypto_cipher_encrypt_one(tfm, src, iv);
-		crypto_xor_cpy(iv, tmpbuf, src, bsize);
+		memcpy(tmpbuf, dst, bsize);
+		crypto_xor(iv, dst, bsize);
+		crypto_cipher_encrypt_one(tfm, dst, iv);
+		crypto_xor_cpy(iv, tmpbuf, dst, bsize);
 
-		src += bsize;
+		dst += bsize;
 	} while ((nbytes -= bsize) >= bsize);
 
 	return nbytes;
@@ -89,8 +89,8 @@ static int crypto_pcbc_decrypt_segment(struct skcipher_request *req,
 				       struct crypto_cipher *tfm)
 {
 	int bsize = crypto_cipher_blocksize(tfm);
+	const u8 *src = walk->src.virt.addr;
 	unsigned int nbytes = walk->nbytes;
-	u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	u8 * const iv = walk->iv;
 
@@ -112,17 +112,17 @@ static int crypto_pcbc_decrypt_inplace(struct skcipher_request *req,
 {
 	int bsize = crypto_cipher_blocksize(tfm);
 	unsigned int nbytes = walk->nbytes;
-	u8 *src = walk->src.virt.addr;
+	u8 *dst = walk->dst.virt.addr;
 	u8 * const iv = walk->iv;
 	u8 tmpbuf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(u32));
 
 	do {
-		memcpy(tmpbuf, src, bsize);
-		crypto_cipher_decrypt_one(tfm, src, src);
-		crypto_xor(src, iv, bsize);
-		crypto_xor_cpy(iv, src, tmpbuf, bsize);
+		memcpy(tmpbuf, dst, bsize);
+		crypto_cipher_decrypt_one(tfm, dst, dst);
+		crypto_xor(dst, iv, bsize);
+		crypto_xor_cpy(iv, dst, tmpbuf, bsize);
 
-		src += bsize;
+		dst += bsize;
 	} while ((nbytes -= bsize) >= bsize);
 
 	return nbytes;
diff --git a/crypto/xctr.c b/crypto/xctr.c
index 6ed9c85ededa..9c536ab6d2e5 100644
--- a/crypto/xctr.c
+++ b/crypto/xctr.c
@@ -78,7 +78,7 @@ static int crypto_xctr_crypt_inplace(struct skcipher_walk *walk,
 		   crypto_cipher_alg(tfm)->cia_encrypt;
 	unsigned long alignmask = crypto_cipher_alignmask(tfm);
 	unsigned int nbytes = walk->nbytes;
-	u8 *data = walk->src.virt.addr;
+	u8 *data = walk->dst.virt.addr;
 	u8 tmp[XCTR_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
 	u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1);
 	__le32 ctr32 = cpu_to_le32(byte_ctr / XCTR_BLOCKSIZE + 1);
diff --git a/crypto/xts.c b/crypto/xts.c
index 821060ede2cf..31529c9ef08f 100644
--- a/crypto/xts.c
+++ b/crypto/xts.c
@@ -99,7 +99,7 @@ static int xts_xor_tweak(struct skcipher_request *req, bool second_pass,
 
 	while (w.nbytes) {
 		unsigned int avail = w.nbytes;
-		le128 *wsrc;
+		const le128 *wsrc;
 		le128 *wdst;
 
 		wsrc = w.src.virt.addr;