Apply preempt_rt patch-4.9-rt1.patch.xz

[zynq/linux.git] / net / core / filter.c

diff --git a/net/core/filter.c b/net/core/filter.c
index 00351cdf7d0c3f5fe1657e02b96b7a90891e0385..b86e9681a88ee4db46ea66fb74c3f0ec0bf6f110 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1628,11 +1628,24 @@ static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
        return dev_forward_skb(dev, skb);
 }
 
+static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
+                                     struct sk_buff *skb)
+{
+       int ret = ____dev_forward_skb(dev, skb);
+
+       if (likely(!ret)) {
+               skb->dev = dev;
+               ret = netif_rx(skb);
+       }
+
+       return ret;
+}
+
 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
 {
        int ret;
 
-       if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
+       if (unlikely(xmit_rec_read() > XMIT_RECURSION_LIMIT)) {
                net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
                kfree_skb(skb);
                return -ENETDOWN;
@@ -1640,13 +1653,58 @@ static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
 
        skb->dev = dev;
 
-       __this_cpu_inc(xmit_recursion);
+       xmit_rec_inc();
        ret = dev_queue_xmit(skb);
-       __this_cpu_dec(xmit_recursion);
+       xmit_rec_dec();
 
        return ret;
 }
 
+static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
+                                u32 flags)
+{
+       /* skb->mac_len is not set on normal egress */
+       unsigned int mlen = skb->network_header - skb->mac_header;
+
+       __skb_pull(skb, mlen);
+
+       /* At ingress, the mac header has already been pulled once.
+        * At egress, skb_pospull_rcsum has to be done in case that
+        * the skb is originated from ingress (i.e. a forwarded skb)
+        * to ensure that rcsum starts at net header.
+        */
+       if (!skb_at_tc_ingress(skb))
+               skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
+       skb_pop_mac_header(skb);
+       skb_reset_mac_len(skb);
+       return flags & BPF_F_INGRESS ?
+              __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
+}
+
+static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
+                                u32 flags)
+{
+       bpf_push_mac_rcsum(skb);
+       return flags & BPF_F_INGRESS ?
+              __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
+}
+
+static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
+                         u32 flags)
+{
+       switch (dev->type) {
+       case ARPHRD_TUNNEL:
+       case ARPHRD_TUNNEL6:
+       case ARPHRD_SIT:
+       case ARPHRD_IPGRE:
+       case ARPHRD_VOID:
+       case ARPHRD_NONE:
+               return __bpf_redirect_no_mac(skb, dev, flags);
+       default:
+               return __bpf_redirect_common(skb, dev, flags);
+       }
+}
+
 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
 {
        struct net_device *dev;
@@ -1675,10 +1733,7 @@ BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
                return -ENOMEM;
        }
 
-       bpf_push_mac_rcsum(clone);
-
-       return flags & BPF_F_INGRESS ?
-              __bpf_rx_skb(dev, clone) : __bpf_tx_skb(dev, clone);
+       return __bpf_redirect(clone, dev, flags);
 }
 
 static const struct bpf_func_proto bpf_clone_redirect_proto = {
@@ -1722,10 +1777,7 @@ int skb_do_redirect(struct sk_buff *skb)
                return -EINVAL;
        }
 
-       bpf_push_mac_rcsum(skb);
-
-       return ri->flags & BPF_F_INGRESS ?
-              __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
+       return __bpf_redirect(skb, dev, ri->flags);
 }
 
 static const struct bpf_func_proto bpf_redirect_proto = {