[CRYPTO] api: fix crypto_alloc_base() return value

This patch makes crypto_alloc_base() return proper return value.

- If kzalloc() failure happens within __crypto_alloc_tfm(),
  crypto_alloc_base() returns NULL. But crypto_alloc_base()
  is supposed to return error code as pointer. So this patch
  makes it return -ENOMEM in that case.

- crypto_alloc_base() is suppose to return -EINTR, if it is
  interrupted by signal. But it may not return -EINTR.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/api.c

@@ -331,7 +331,7 @@ struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 flags)
 	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, flags);
 	tfm = kzalloc(tfm_size, GFP_KERNEL);
 	if (tfm == NULL)
-		goto out;
+		goto out_err;
 
 	tfm->__crt_alg = alg;
 
@@ -355,6 +355,7 @@ cra_init_failed:
 	crypto_exit_ops(tfm);
 out_free_tfm:
 	kfree(tfm);
+out_err:
 	tfm = ERR_PTR(err);
 out:
 	return tfm;
@@ -414,14 +415,14 @@ struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
 		struct crypto_alg *alg;
 
 		alg = crypto_alg_mod_lookup(alg_name, type, mask);
-		err = PTR_ERR(alg);
-		tfm = ERR_PTR(err);
-		if (IS_ERR(alg))
+		if (IS_ERR(alg)) {
+			err = PTR_ERR(alg);
 			goto err;
+		}
 
 		tfm = __crypto_alloc_tfm(alg, 0);
 		if (!IS_ERR(tfm))
-			break;
+			return tfm;
 
 		crypto_mod_put(alg);
 		err = PTR_ERR(tfm);
@@ -433,9 +434,9 @@ err:
 			err = -EINTR;
 			break;
 		}
-	};
+	}
 
-	return tfm;
+	return ERR_PTR(err);
 }
 EXPORT_SYMBOL_GPL(crypto_alloc_base);