[PATCH net-next 4/6] bpf: Fix tcp_cong_kern.c sample program

[Lawrence Brakmo <brakmo@fb.com>]

The program was returning -1 in some cases which is not allowed
by the verifier any longer.

Fixes: bb56d4449d8b ("bpf: Sample BPF program to set congestion control")
Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
---
 samples/bpf/tcp_cong_kern.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/samples/bpf/tcp_cong_kern.c b/samples/bpf/tcp_cong_kern.c
index dac15bc..ad0f1ba 100644
--- a/samples/bpf/tcp_cong_kern.c
+++ b/samples/bpf/tcp_cong_kern.c
@@ -39,8 +39,10 @@ int bpf_cong(struct bpf_sock_ops *skops)
 	 * if neither port numberis 55601
 	 */
 	if (bpf_ntohl(skops->remote_port) != 55601 &&
-	    skops->local_port != 55601)
-		return -1;
+	    skops->local_port != 55601) {
+		skops->reply = -1;
+		return 1;
+	}
 
 	op = (int) skops->op;
 
-- 
2.9.5