From b40863c667c16b7a73d4f034a8eab67029b5b15a Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 18 Sep 2012 20:44:49 +0000 Subject: [PATCH] net: more accurate network taps in transmit path dev_queue_xmit_nit() should be called right before ndo_start_xmit() calls or we might give wrong packet contents to taps users : Packet checksum can be changed, or packet can be linearized or segmented, and segments partially sent for the later case. Also a memory allocation can fail and packet never really hit the driver entry point. Reported-by: Jamie Gloudon Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/dev.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index dcc673d0674c..52cd1d7f004a 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2213,9 +2213,6 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, if (dev->priv_flags & IFF_XMIT_DST_RELEASE) skb_dst_drop(skb); - if (!list_empty(&ptype_all)) - dev_queue_xmit_nit(skb, dev); - features = netif_skb_features(skb); if (vlan_tx_tag_present(skb) && @@ -2250,6 +2247,9 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, } } + if (!list_empty(&ptype_all)) + dev_queue_xmit_nit(skb, dev); + skb_len = skb->len; rc = ops->ndo_start_xmit(skb, dev); trace_net_dev_xmit(skb, rc, dev, skb_len); @@ -2272,6 +2272,9 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, if (dev->priv_flags & IFF_XMIT_DST_RELEASE) skb_dst_drop(nskb); + if (!list_empty(&ptype_all)) + dev_queue_xmit_nit(nskb, dev); + skb_len = nskb->len; rc = ops->ndo_start_xmit(nskb, dev); trace_net_dev_xmit(nskb, rc, dev, skb_len); -- GitLab