From 5c331fc8c19e181bffab46e9d18e1637cdc47170 Mon Sep 17 00:00:00 2001 From: Ang Way Chuang Date: Thu, 27 May 2010 02:02:09 -0300 Subject: [PATCH] V4L/DVB: dvb-core: Fix ULE decapsulation bug Fix ULE decapsulation bug when less than 4 bytes of ULE SNDU is packed into the remaining bytes of a MPEG2-TS frame ULE (Unidirectional Lightweight Encapsulation RFC 4326) decapsulation code has a bug that incorrectly treats ULE SNDU packed into the remaining 2 or 3 bytes of a MPEG2-TS frame as having invalid pointer field on the subsequent MPEG2-TS frame. Signed-off-by: Ang Way Chuang Acked-by: Jarod Wilson Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb/dvb-core/dvb_net.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/media/dvb/dvb-core/dvb_net.c b/drivers/media/dvb/dvb-core/dvb_net.c index f6dac2b..6c3a8a0 100644 --- a/drivers/media/dvb/dvb-core/dvb_net.c +++ b/drivers/media/dvb/dvb-core/dvb_net.c @@ -351,6 +351,7 @@ static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len ) const u8 *ts, *ts_end, *from_where = NULL; u8 ts_remain = 0, how_much = 0, new_ts = 1; struct ethhdr *ethh = NULL; + bool error = false; #ifdef ULE_DEBUG /* The code inside ULE_DEBUG keeps a history of the last 100 TS cells processed. */ @@ -460,10 +461,16 @@ static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len ) /* Drop partly decoded SNDU, reset state, resync on PUSI. */ if (priv->ule_skb) { - dev_kfree_skb( priv->ule_skb ); + error = true; + dev_kfree_skb(priv->ule_skb); + } + + if (error || priv->ule_sndu_remain) { dev->stats.rx_errors++; dev->stats.rx_frame_errors++; + error = false; } + reset_ule(priv); priv->need_pusi = 1; continue; @@ -535,6 +542,7 @@ static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len ) from_where += 2; } + priv->ule_sndu_remain = priv->ule_sndu_len + 2; /* * State of current TS: * ts_remain (remaining bytes in the current TS cell) @@ -544,6 +552,7 @@ static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len ) */ switch (ts_remain) { case 1: + priv->ule_sndu_remain--; priv->ule_sndu_type = from_where[0] << 8; priv->ule_sndu_type_1 = 1; /* first byte of ule_type is set. */ ts_remain -= 1; from_where += 1; @@ -557,6 +566,7 @@ static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len ) default: /* complete ULE header is present in current TS. */ /* Extract ULE type field. */ if (priv->ule_sndu_type_1) { + priv->ule_sndu_type_1 = 0; priv->ule_sndu_type |= from_where[0]; from_where += 1; /* points to payload start. */ ts_remain -= 1; -- 2.7.4