Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto fixes from Herbert Xu:
 "This push fixes the following issues:

   - buffer overread in RSA

   - potential use after free in algif_aead.

   - error path null pointer dereference in af_alg

   - forbid combinations such as hmac(hmac(sha3)) which may crash

   - crash in salsa20 due to incorrect API usage"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: salsa20 - fix blkcipher_walk API usage
  crypto: hmac - require that the underlying hash algorithm is unkeyed
  crypto: af_alg - fix NULL pointer dereference in
  crypto: algif_aead - fix reference counting of null skcipher
  crypto: rsa - fix buffer overread when stripping leading zeroes

arch/x86/crypto/salsa20_glue.c

@@ -59,13 +59,6 @@ static int encrypt(struct blkcipher_desc *desc,
 
 	salsa20_ivsetup(ctx, walk.iv);
 
-	if (likely(walk.nbytes == nbytes))
-	{
-		salsa20_encrypt_bytes(ctx, walk.src.virt.addr,
-				      walk.dst.virt.addr, nbytes);
-		return blkcipher_walk_done(desc, &walk, 0);
-	}
-
 	while (walk.nbytes >= 64) {
 		salsa20_encrypt_bytes(ctx, walk.src.virt.addr,
 				      walk.dst.virt.addr,

crypto/af_alg.c

@@ -672,14 +672,15 @@ void af_alg_free_areq_sgls(struct af_alg_async_req *areq)
 	}
 
 	tsgl = areq->tsgl;
-	for_each_sg(tsgl, sg, areq->tsgl_entries, i) {
-		if (!sg_page(sg))
-			continue;
-		put_page(sg_page(sg));
-	}
+	if (tsgl) {
+		for_each_sg(tsgl, sg, areq->tsgl_entries, i) {
+			if (!sg_page(sg))
+				continue;
+			put_page(sg_page(sg));
+		}
 
-	if (areq->tsgl && areq->tsgl_entries)
 		sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl));
+	}
 }
 EXPORT_SYMBOL_GPL(af_alg_free_areq_sgls);
 

crypto/algif_aead.c

@@ -503,6 +503,7 @@ static void aead_release(void *private)
 	struct aead_tfm *tfm = private;
 
 	crypto_free_aead(tfm->aead);
+	crypto_put_default_null_skcipher2();
 	kfree(tfm);
 }
 
@@ -535,7 +536,6 @@ static void aead_sock_destruct(struct sock *sk)
 	unsigned int ivlen = crypto_aead_ivsize(tfm);
 
 	af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
-	crypto_put_default_null_skcipher2();
 	sock_kzfree_s(sk, ctx->iv, ivlen);
 	sock_kfree_s(sk, ctx, ctx->len);
 	af_alg_release_parent(sk);

crypto/hmac.c

@@ -195,11 +195,15 @@ static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb)
 	salg = shash_attr_alg(tb[1], 0, 0);
 	if (IS_ERR(salg))
 		return PTR_ERR(salg);
+	alg = &salg->base;
 
+	/* The underlying hash algorithm must be unkeyed */
 	err = -EINVAL;
+	if (crypto_shash_alg_has_setkey(salg))
+		goto out_put_alg;
+
 	ds = salg->digestsize;
 	ss = salg->statesize;
-	alg = &salg->base;
 	if (ds > alg->cra_blocksize ||
 	    ss < alg->cra_blocksize)
 		goto out_put_alg;

crypto/rsa_helper.c

@@ -30,7 +30,7 @@ int rsa_get_n(void *context, size_t hdrlen, unsigned char tag,
 		return -EINVAL;
 
 	if (fips_enabled) {
-		while (!*ptr && n_sz) {
+		while (n_sz && !*ptr) {
 			ptr++;
 			n_sz--;
 		}

crypto/salsa20_generic.c

@@ -188,13 +188,6 @@ static int encrypt(struct blkcipher_desc *desc,
 
 	salsa20_ivsetup(ctx, walk.iv);
 
-	if (likely(walk.nbytes == nbytes))
-	{
-		salsa20_encrypt_bytes(ctx, walk.dst.virt.addr,
-				      walk.src.virt.addr, nbytes);
-		return blkcipher_walk_done(desc, &walk, 0);
-	}
-
 	while (walk.nbytes >= 64) {
 		salsa20_encrypt_bytes(ctx, walk.dst.virt.addr,
 				      walk.src.virt.addr,

crypto/shash.c

@@ -25,11 +25,12 @@
 
 static const struct crypto_type crypto_shash_type;
 
-static int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
-			   unsigned int keylen)
+int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
+		    unsigned int keylen)
 {
 	return -ENOSYS;
 }
+EXPORT_SYMBOL_GPL(shash_no_setkey);
 
 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
 				  unsigned int keylen)

include/crypto/internal/hash.h

@@ -82,6 +82,14 @@ int ahash_register_instance(struct crypto_template *tmpl,
 			    struct ahash_instance *inst);
 void ahash_free_instance(struct crypto_instance *inst);
 
+int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
+		    unsigned int keylen);
+
+static inline bool crypto_shash_alg_has_setkey(struct shash_alg *alg)
+{
+	return alg->setkey != shash_no_setkey;
+}
+
 int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
 			    struct hash_alg_common *alg,
 			    struct crypto_instance *inst);