From: Dr. Stephen Henson <steve@openssl.org>
Date: Mon, 9 Mar 2015 23:16:33 +0000 (+0000)
Subject: Reject invalid PSS parameters.
X-Git-Tag: OpenSSL_1_1_0-pre1~1512
X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff_plain;h=09f06923e636019c39c807cb59c481375e720556

Reject invalid PSS parameters.

Fix a bug where invalid PSS parameters are not rejected resulting in a
NULL pointer exception. This can be triggered during certificate
verification so could be a DoS attack against a client or a server
enabling client authentication.

Thanks to Brian Carpenter for reporting this issues.

CVE-2015-0208

Reviewed-by: Tim Hudson <tjh@openssl.org>
---

diff --git a/crypto/rsa/rsa_ameth.c b/crypto/rsa/rsa_ameth.c
index 5e8701ac0a..6f4c104858 100644
--- a/crypto/rsa/rsa_ameth.c
+++ b/crypto/rsa/rsa_ameth.c
@@ -703,9 +703,10 @@ static int rsa_item_verify(EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
         RSAerr(RSA_F_RSA_ITEM_VERIFY, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
         return -1;
     }
-    if (rsa_pss_to_ctx(ctx, NULL, sigalg, pkey))
+    if (rsa_pss_to_ctx(ctx, NULL, sigalg, pkey) > 0) {
         /* Carry on */
         return 2;
+    }
     return -1;
 }