From 36d5fe6a000790f56039afe26834265db0a3ad4c Mon Sep 17 00:00:00 2001 From: Zoltan Kiss Date: Wed, 26 Mar 2014 22:37:45 +0000 Subject: core, nfqueue, openvswitch: Orphan frags in skb_zerocopy and handle errors skb_zerocopy can copy elements of the frags array between skbs, but it doesn't orphan them. Also, it doesn't handle errors, so this patch takes care of that as well, and modify the callers accordingly. skb_tx_error() is also added to the callers so they will signal the failed delivery towards the creator of the skb. Signed-off-by: Zoltan Kiss Signed-off-by: David S. Miller --- net/core/skbuff.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) (limited to 'net/core/skbuff.c') diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 869c7afe3b07..97e5a2c3d947 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2127,25 +2127,31 @@ EXPORT_SYMBOL_GPL(skb_zerocopy_headlen); * * The `hlen` as calculated by skb_zerocopy_headlen() specifies the * headroom in the `to` buffer. + * + * Return value: + * 0: everything is OK + * -ENOMEM: couldn't orphan frags of @from due to lack of memory + * -EFAULT: skb_copy_bits() found some problem with skb geometry */ -void -skb_zerocopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen) +int +skb_zerocopy(struct sk_buff *to, struct sk_buff *from, int len, int hlen) { int i, j = 0; int plen = 0; /* length of skb->head fragment */ + int ret; struct page *page; unsigned int offset; BUG_ON(!from->head_frag && !hlen); /* dont bother with small payloads */ - if (len <= skb_tailroom(to)) { - skb_copy_bits(from, 0, skb_put(to, len), len); - return; - } + if (len <= skb_tailroom(to)) + return skb_copy_bits(from, 0, skb_put(to, len), len); if (hlen) { - skb_copy_bits(from, 0, skb_put(to, hlen), hlen); + ret = skb_copy_bits(from, 0, skb_put(to, hlen), hlen); + if (unlikely(ret)) + return ret; len -= hlen; } else { plen = min_t(int, skb_headlen(from), len); @@ -2163,6 +2169,11 @@ skb_zerocopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen) to->len += len + plen; to->data_len += len + plen; + if (unlikely(skb_orphan_frags(from, GFP_ATOMIC))) { + skb_tx_error(from); + return -ENOMEM; + } + for (i = 0; i < skb_shinfo(from)->nr_frags; i++) { if (!len) break; @@ -2173,6 +2184,8 @@ skb_zerocopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen) j++; } skb_shinfo(to)->nr_frags = j; + + return 0; } EXPORT_SYMBOL_GPL(skb_zerocopy); -- cgit v1.2.3 From 53d6471cef17262d3ad1c7ce8982a234244f68ec Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Thu, 27 Mar 2014 17:26:18 -0400 Subject: 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(-) (limited to 'net/core/skbuff.c') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e8eeebd49a98..daafd9561cbc 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 b1b0c8d4d7df..45fa2f11f84d 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 97e5a2c3d947..90b96a11b974 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); -- cgit v1.2.3