crypto: rsa-pkcs1pad - only allow with rsa

commit 9b30430ea356f237945e52f8a3a42158877bd5a9 upstream.

The pkcs1pad template can be instantiated with an arbitrary akcipher
algorithm, which doesn't make sense; it is specifically an RSA padding
scheme.  Make it check that the underlying algorithm really is RSA.

Fixes: 3d5b1ecdea6f ("crypto: rsa - RSA padding algorithm")
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/crypto/rsa-pkcs1pad.c b/crypto/rsa-pkcs1pad.c
index 8ac3e73e8ea65121a9ccfbe9e598d757f426e933..1b354578142583a46fb47aa81048e9a8dd0ac88c 100644 (file)
--- a/crypto/rsa-pkcs1pad.c
+++ b/crypto/rsa-pkcs1pad.c
@@ -621,6 +621,11 @@ static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
 
        rsa_alg = crypto_spawn_akcipher_alg(&ctx->spawn);
 
+       if (strcmp(rsa_alg->base.cra_name, "rsa") != 0) {
+               err = -EINVAL;
+               goto err_free_inst;
+       }
+
        err = -ENAMETOOLONG;
        hash_name = crypto_attr_alg_name(tb[2]);
        if (IS_ERR(hash_name)) {