From 6ec82562ffc6f297d0de36d65776cff8e5704867 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 6 May 2010 00:53:53 -0700
Subject: [PATCH] veth: Dont kfree_skb() after dev_forward_skb()
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In case of congestion, netif_rx() frees the skb, so we must assume
dev_forward_skb() also consume skb.
Bug introduced by commit 445409602c092
(veth: move loopback logic to common location)
We must change dev_forward_skb() to always consume skb, and veth to not
double free it.
Bug report : http://marc.info/?l=linux-netdev&m=127310770900442&w=3
Reported-by: MartÃn Ferrari <martin.ferrari@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/veth.c | 1 -
net/core/dev.c | 11 +++++------
2 files changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index f9f0730b53d5..5ec542dd5b50 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -187,7 +187,6 @@ tx_drop:
return NETDEV_TX_OK;
rx_drop:
- kfree_skb(skb);
rcv_stats->rx_dropped++;
return NETDEV_TX_OK;
}
diff --git a/net/core/dev.c b/net/core/dev.c
index f769098774b7..264137fce3a2 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1451,7 +1451,7 @@ static inline void net_timestamp(struct sk_buff *skb)
*
* return values:
* NET_RX_SUCCESS (no congestion)
- * NET_RX_DROP (packet was dropped)
+ * NET_RX_DROP (packet was dropped, but freed)
*
* dev_forward_skb can be used for injecting an skb from the
* start_xmit function of one device into the receive queue
@@ -1465,12 +1465,11 @@ int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
{
skb_orphan(skb);
- if (!(dev->flags & IFF_UP))
- return NET_RX_DROP;
-
- if (skb->len > (dev->mtu + dev->hard_header_len))
+ if (!(dev->flags & IFF_UP) ||
+ (skb->len > (dev->mtu + dev->hard_header_len))) {
+ kfree_skb(skb);
return NET_RX_DROP;
-
+ }
skb_set_dev(skb, dev);
skb->tstamp.tv64 = 0;
skb->pkt_type = PACKET_HOST;
--
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