From a8af38d209ecefcd9ab17670a18f445e95f575e2 Mon Sep 17 00:00:00 2001
From: Denis Kenzior <denkenz@gmail.com>
Date: Wed, 14 Oct 2009 16:03:36 -0500
Subject: [PATCH] Fix: Be more paranoid in checking DLC validity

---
 gatchat/gatmux.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/gatchat/gatmux.c b/gatchat/gatmux.c
index 424a5743..0b42ebcf 100644
--- a/gatchat/gatmux.c
+++ b/gatchat/gatmux.c
@@ -306,13 +306,19 @@ int g_at_mux_raw_write(GAtMux *mux, const void *data, int towrite)
 void g_at_mux_feed_dlc_data(GAtMux *mux, guint8 dlc,
 				const void *data, int tofeed)
 {
-	GAtMuxChannel *channel = mux->dlcs[dlc-1];
+	GAtMuxChannel *channel;
+
 	int written;
 	int offset;
 	int bit;
 
 	DBG("deliver_data: dlc: %d, channel: %p", dlc, channel);
 
+	if (dlc < 1 || dlc > MAX_CHANNELS)
+		return;
+
+	channel = mux->dlcs[dlc-1];
+
 	if (channel == NULL)
 		return;
 
@@ -330,11 +336,17 @@ void g_at_mux_feed_dlc_data(GAtMux *mux, guint8 dlc,
 
 void g_at_mux_set_dlc_status(GAtMux *mux, guint8 dlc, int status)
 {
+	GAtMuxChannel *channel;
+
 	DBG("Got status %d, for channel %d", status, channel);
 
 	if (dlc < 1 || dlc > MAX_CHANNELS)
 		return;
 
+	channel = mux->dlcs[dlc-1];
+	if (channel == NULL)
+		return;
+
 	if (status & G_AT_MUX_DLC_STATUS_RTR) {
 		GSList *l;