Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-05-31

The following pull-request contains BPF updates for your *net-next* tree.

Lots of exciting new features in the first PR of this developement cycle!
The main changes are:

1) misc verifier improvements, from Alexei.

2) bpftool can now convert btf to valid C, from Andrii.

3) verifier can insert explicit ZEXT insn when requested by 32-bit JITs.
   This feature greatly improves BPF speed on 32-bit architectures. From Jiong.

4) cgroups will now auto-detach bpf programs. This fixes issue of thousands
   bpf programs got stuck in dying cgroups. From Roman.

5) new bpf_send_signal() helper, from Yonghong.

6) cgroup inet skb programs can signal CN to the stack, from Lawrence.

7) miscellaneous cleanups, from many developers.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 11 deletions

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index d8f2a22c6ff7..ceca5285d9b4 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -287,16 +287,9 @@ static int ip_finish_output_gso(struct net *net, struct sock *sk,
 	return ret;
 }
 
-static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+static int __ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	unsigned int mtu;
-	int ret;
-
-	ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb);
-	if (ret) {
-		kfree_skb(skb);
-		return ret;
-	}
 
 #if defined(CONFIG_NETFILTER) && defined(CONFIG_XFRM)
 	/* Policy lookup after SNAT yielded a new policy */
@@ -315,18 +308,37 @@ static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *sk
 	return ip_finish_output2(net, sk, skb);
 }
 
+static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+	int ret;
+
+	ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb);
+	switch (ret) {
+	case NET_XMIT_SUCCESS:
+		return __ip_finish_output(net, sk, skb);
+	case NET_XMIT_CN:
+		return __ip_finish_output(net, sk, skb) ? : ret;
+	default:
+		kfree_skb(skb);
+		return ret;
+	}
+}
+
 static int ip_mc_finish_output(struct net *net, struct sock *sk,
 			       struct sk_buff *skb)
 {
 	int ret;
 
 	ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb);
-	if (ret) {
+	switch (ret) {
+	case NET_XMIT_SUCCESS:
+		return dev_loopback_xmit(net, sk, skb);
+	case NET_XMIT_CN:
+		return dev_loopback_xmit(net, sk, skb) ? : ret;
+	default:
 		kfree_skb(skb);
 		return ret;
 	}
-
-	return dev_loopback_xmit(net, sk, skb);
 }
 
 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb)