diff options
-rw-r--r-- | include/linux/skbuff.h | 3 | ||||
-rw-r--r-- | net/core/dev.c | 5 | ||||
-rw-r--r-- | net/ipv4/ip_output.c | 1 | ||||
-rw-r--r-- | net/openvswitch/datapath.c | 5 | ||||
-rw-r--r-- | net/xfrm/xfrm_output.c | 2 |
5 files changed, 11 insertions, 5 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 4307e20a4a4a..1f17abe23725 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3320,7 +3320,8 @@ struct skb_gso_cb { int encap_level; __u16 csum_start; }; -#define SKB_GSO_CB(skb) ((struct skb_gso_cb *)(skb)->cb) +#define SKB_SGO_CB_OFFSET 32 +#define SKB_GSO_CB(skb) ((struct skb_gso_cb *)((skb)->cb + SKB_SGO_CB_OFFSET)) static inline int skb_tnl_header_len(const struct sk_buff *inner_skb) { diff --git a/net/core/dev.c b/net/core/dev.c index a42b232805a5..185a3398c651 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2479,6 +2479,8 @@ static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) * * It may return NULL if the skb requires no segmentation. This is * only possible when GSO is used for verifying header integrity. + * + * Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb. */ struct sk_buff *__skb_gso_segment(struct sk_buff *skb, netdev_features_t features, bool tx_path) @@ -2493,6 +2495,9 @@ struct sk_buff *__skb_gso_segment(struct sk_buff *skb, return ERR_PTR(err); } + BUILD_BUG_ON(SKB_SGO_CB_OFFSET + + sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb)); + SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb); SKB_GSO_CB(skb)->encap_level = 0; diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index fe16f418e775..51573f8a39bc 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -235,6 +235,7 @@ static int ip_finish_output_gso(struct sock *sk, struct sk_buff *skb) * from host network stack. */ features = netif_skb_features(skb); + BUILD_BUG_ON(sizeof(*IPCB(skb)) > SKB_SGO_CB_OFFSET); segs = skb_gso_segment(skb, features & ~NETIF_F_GSO_MASK); if (IS_ERR_OR_NULL(segs)) { kfree_skb(skb); diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index 27e14962b504..b3fe02a2339e 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -337,12 +337,10 @@ static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb, unsigned short gso_type = skb_shinfo(skb)->gso_type; struct sw_flow_key later_key; struct sk_buff *segs, *nskb; - struct ovs_skb_cb ovs_cb; int err; - ovs_cb = *OVS_CB(skb); + BUILD_BUG_ON(sizeof(*OVS_CB(skb)) > SKB_SGO_CB_OFFSET); segs = __skb_gso_segment(skb, NETIF_F_SG, false); - *OVS_CB(skb) = ovs_cb; if (IS_ERR(segs)) return PTR_ERR(segs); if (segs == NULL) @@ -360,7 +358,6 @@ static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb, /* Queue all of the segments. */ skb = segs; do { - *OVS_CB(skb) = ovs_cb; if (gso_type & SKB_GSO_UDP && skb != segs) key = &later_key; diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c index fbcedbe33190..5097dce5b916 100644 --- a/net/xfrm/xfrm_output.c +++ b/net/xfrm/xfrm_output.c @@ -153,6 +153,8 @@ static int xfrm_output_gso(struct sock *sk, struct sk_buff *skb) { struct sk_buff *segs; + BUILD_BUG_ON(sizeof(*IPCB(skb)) > SKB_SGO_CB_OFFSET); + BUILD_BUG_ON(sizeof(*IP6CB(skb)) > SKB_SGO_CB_OFFSET); segs = skb_gso_segment(skb, 0); kfree_skb(skb); if (IS_ERR(segs)) |