Update session_ticket.c to add support for zero length session tickets returned from the server

check that ticket_len > 0 prior to calling gnutls_realloc_fast

Signed-off-by: Rod Rivers <5981058-rrivers2@users.noreply.gitlab.com>

1 files changed, 10 insertions, 8 deletions

diff --git a/lib/ext/session_ticket.c b/lib/ext/session_ticket.c
index c854d9c2a9..8d4595821a 100644
--- a/lib/ext/session_ticket.c
+++ b/lib/ext/session_ticket.c
@@ -787,15 +787,17 @@ int _gnutls_recv_new_session_ticket(gnutls_session_t session)
 		ret = GNUTLS_E_MEMORY_ERROR;
 		goto error;
 	}
-	priv->session_ticket =
-	    gnutls_realloc_fast(priv->session_ticket, ticket_len);
-	if (!priv->session_ticket) {
-		gnutls_free(priv);
-		gnutls_assert();
-		ret = GNUTLS_E_MEMORY_ERROR;
-		goto error;
+	if (ticket_len > 0) {
+		priv->session_ticket =
+		    gnutls_realloc_fast(priv->session_ticket, ticket_len);
+		if (!priv->session_ticket) {
+			gnutls_free(priv);
+			gnutls_assert();
+			ret = GNUTLS_E_MEMORY_ERROR;
+			goto error;
+		}
+		memcpy(priv->session_ticket, p, ticket_len);
 	}
-	memcpy(priv->session_ticket, p, ticket_len);
 	priv->session_ticket_len = ticket_len;
 	epriv = priv;