From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
Date: Fri, 15 Nov 2013 08:54:26 +0000 (+0100)
Subject: check for a valid blocksize prior to entering loop
X-Git-Tag: gnutls_3_3_0pre0~596
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=33cda206abc5f77d7797902fcea9297e47db4c8d;p=thirdparty%2Fgnutls.git

check for a valid blocksize prior to entering loop
---

diff --git a/lib/gnutls_state.c b/lib/gnutls_state.c
index a609fb97a5..231e6b0b64 100644
--- a/lib/gnutls_state.c
+++ b/lib/gnutls_state.c
@@ -777,13 +777,13 @@ P_hash(gnutls_mac_algorithm_t algorithm,
 	int output_bytes, result;
 	const mac_entry_st *me = mac_to_entry(algorithm);
 
-	if (seed_size > MAX_SEED_SIZE || total_bytes <= 0) {
+	blocksize = _gnutls_mac_get_algo_len(me);
+
+	if (seed_size > MAX_SEED_SIZE || total_bytes <= 0 || blocksize == 0) {
 		gnutls_assert();
 		return GNUTLS_E_INTERNAL_ERROR;
 	}
 
-	blocksize = _gnutls_mac_get_algo_len(me);
-
 	output_bytes = 0;
 	do {
 		output_bytes += blocksize;