From: Jouni Malinen <j@w1.fi>
Date: Sat, 6 Dec 2014 16:34:23 +0000 (+0200)
Subject: TLS: Reorder length bounds checking to avoid static analyzer warning
X-Git-Tag: hostap_2_4~902
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7d043641044566f08e059774caab50fc93290dcf;p=thirdparty%2Fhostap.git

TLS: Reorder length bounds checking to avoid static analyzer warning

For some reason, "pos + len > end" is not clear enough, but "len > end -
pos" is recognized. Use that to get rid of a false positive from a
static analyzer (CID 72697).

Signed-off-by: Jouni Malinen <j@w1.fi>
---

diff --git a/src/tls/tlsv1_server_read.c b/src/tls/tlsv1_server_read.c
index 728e13725..310966c2d 100644
--- a/src/tls/tlsv1_server_read.c
+++ b/src/tls/tlsv1_server_read.c
@@ -626,7 +626,7 @@ static int tls_process_client_key_exchange_dh(
 	dh_yc_len = WPA_GET_BE16(pos);
 	dh_yc = pos + 2;
 
-	if (dh_yc + dh_yc_len > end) {
+	if (dh_yc_len > end - dh_yc) {
 		tlsv1_server_log(conn, "Client public value overflow (length %d)",
 				 dh_yc_len);
 		tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,