From 53d6471cef17262d3ad1c7ce8982a234244f68ec Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Thu, 27 Mar 2014 17:26:18 -0400 Subject: [PATCH] net: Account for all vlan headers in skb_mac_gso_segment skb_network_protocol() already accounts for multiple vlan headers that may be present in the skb. However, skb_mac_gso_segment() doesn't know anything about it and assumes that skb->mac_len is set correctly to skip all mac headers. That may not always be the case. If we are simply forwarding the packet (via bridge or macvtap), all vlan headers may not be accounted for. A simple solution is to allow skb_network_protocol to return the vlan depth it has calculated. This way skb_mac_gso_segment will correctly skip all mac headers. Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- include/linux/netdevice.h | 2 +- net/core/dev.c | 13 +++++++++---- net/core/skbuff.c | 3 ++- 3 files changed, 12 insertions(+), 6 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e8eeebd..daafd95 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3014,7 +3014,7 @@ struct sk_buff *skb_gso_segment(struct sk_buff *skb, netdev_features_t features) { return __skb_gso_segment(skb, features, true); } -__be16 skb_network_protocol(struct sk_buff *skb); +__be16 skb_network_protocol(struct sk_buff *skb, int *depth); static inline bool can_checksum_protocol(netdev_features_t features, __be16 protocol) diff --git a/net/core/dev.c b/net/core/dev.c index b1b0c8d..45fa2f1 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2286,7 +2286,7 @@ out: } EXPORT_SYMBOL(skb_checksum_help); -__be16 skb_network_protocol(struct sk_buff *skb) +__be16 skb_network_protocol(struct sk_buff *skb, int *depth) { __be16 type = skb->protocol; int vlan_depth = ETH_HLEN; @@ -2313,6 +2313,8 @@ __be16 skb_network_protocol(struct sk_buff *skb) vlan_depth += VLAN_HLEN; } + *depth = vlan_depth; + return type; } @@ -2326,12 +2328,13 @@ struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb, { struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); struct packet_offload *ptype; - __be16 type = skb_network_protocol(skb); + int vlan_depth = skb->mac_len; + __be16 type = skb_network_protocol(skb, &vlan_depth); if (unlikely(!type)) return ERR_PTR(-EINVAL); - __skb_pull(skb, skb->mac_len); + __skb_pull(skb, vlan_depth); rcu_read_lock(); list_for_each_entry_rcu(ptype, &offload_base, list) { @@ -2498,8 +2501,10 @@ static netdev_features_t harmonize_features(struct sk_buff *skb, const struct net_device *dev, netdev_features_t features) { + int tmp; + if (skb->ip_summed != CHECKSUM_NONE && - !can_checksum_protocol(features, skb_network_protocol(skb))) { + !can_checksum_protocol(features, skb_network_protocol(skb, &tmp))) { features &= ~NETIF_F_ALL_CSUM; } else if (illegal_highdma(dev, skb)) { features &= ~NETIF_F_SG; diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 97e5a2c..90b96a1 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2879,8 +2879,9 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, int err = -ENOMEM; int i = 0; int pos; + int dummy; - proto = skb_network_protocol(head_skb); + proto = skb_network_protocol(head_skb, &dummy); if (unlikely(!proto)) return ERR_PTR(-EINVAL); -- 2.7.4