[media] dvb_demux: Transport stream continuity check fix

This patch avoids incrementing continuity counter
demux->cnt_storage[pid] for TS packets without payload in accordance
with ISO /IEC 13818-1.

[mchehab@redhat.com: unmangle whitespacing and fix CodingStyle.
 Also checked ISO/IEC spec: patch is according with it]
Reviewed-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: John Smith <johns90812@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/dvb-core/dvb_demux.c b/drivers/media/dvb-core/dvb_demux.c
index d319717..71641b2 100644 (file)
--- a/drivers/media/dvb-core/dvb_demux.c
+++ b/drivers/media/dvb-core/dvb_demux.c
@@ -440,20 +440,22 @@ static void dvb_dmx_swfilter_packet(struct dvb_demux *demux, const u8 *buf)
                if (!dvb_demux_feed_err_pkts)
                        return;
        } else /* if TEI bit is set, pid may be wrong- skip pkt counter */
-       if (demux->cnt_storage && dvb_demux_tscheck) {
-               /* check pkt counter */
-               if (pid < MAX_PID) {
-                       if ((buf[3] & 0xf) != demux->cnt_storage[pid])
-                               dprintk_tscheck("TS packet counter mismatch. "
-                                               "PID=0x%x expected 0x%x "
-                                               "got 0x%x\n",
+               if (demux->cnt_storage && dvb_demux_tscheck) {
+                       /* check pkt counter */
+                       if (pid < MAX_PID) {
+                               if (buf[3] & 0x10)
+                                       demux->cnt_storage[pid] =
+                                               (demux->cnt_storage[pid] + 1) & 0xf;
+
+                               if ((buf[3] & 0xf) != demux->cnt_storage[pid]) {
+                                       dprintk_tscheck("TS packet counter mismatch. PID=0x%x expected 0x%x got 0x%x\n",
                                                pid, demux->cnt_storage[pid],
                                                buf[3] & 0xf);
-
-                       demux->cnt_storage[pid] = ((buf[3] & 0xf) + 1)&0xf;
+                                       demux->cnt_storage[pid] = buf[3] & 0xf;
+                               }
+                       }
+                       /* end check */
                }
-               /* end check */
-       }
 
        list_for_each_entry(feed, &demux->feed_list, list_head) {
                if ((feed->pid != pid) && (feed->pid != 0x2000))