From 03e982eed419da37e9cac1d759097dbe10447190 Mon Sep 17 00:00:00 2001 From: Lawrence Brakmo Date: Fri, 10 Nov 2017 22:19:55 -0800 Subject: [PATCH] bpf: Fix tcp_clamp_kern.c sample program The program was returning -1 in some cases which is not allowed by the verifier any longer. Fixes: 390ee7e29fc8 ("bpf: enforce return code for cgroup-bpf programs") Signed-off-by: Lawrence Brakmo Signed-off-by: David S. Miller --- samples/bpf/tcp_clamp_kern.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/samples/bpf/tcp_clamp_kern.c b/samples/bpf/tcp_clamp_kern.c index d68eadd9ca2d..f4225c9d2c0c 100644 --- a/samples/bpf/tcp_clamp_kern.c +++ b/samples/bpf/tcp_clamp_kern.c @@ -41,8 +41,10 @@ int bpf_clamp(struct bpf_sock_ops *skops) /* For testing purposes, only execute rest of BPF program * if neither port numberis 55601 */ - if (bpf_ntohl(skops->remote_port) != 55601 && skops->local_port != 55601) - return -1; + if (bpf_ntohl(skops->remote_port) != 55601 && skops->local_port != 55601) { + skops->reply = -1; + return 0; + } op = (int) skops->op; @@ -66,9 +68,9 @@ int bpf_clamp(struct bpf_sock_ops *skops) /* Set sndbuf and rcvbuf of active connections */ rv = bpf_setsockopt(skops, SOL_SOCKET, SO_SNDBUF, &bufsize, sizeof(bufsize)); - rv = rv*100 + bpf_setsockopt(skops, SOL_SOCKET, - SO_RCVBUF, &bufsize, - sizeof(bufsize)); + rv += bpf_setsockopt(skops, SOL_SOCKET, + SO_RCVBUF, &bufsize, + sizeof(bufsize)); break; case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: rv = bpf_setsockopt(skops, SOL_TCP, @@ -80,12 +82,12 @@ int bpf_clamp(struct bpf_sock_ops *skops) rv = bpf_setsockopt(skops, SOL_TCP, TCP_BPF_SNDCWND_CLAMP, &clamp, sizeof(clamp)); - rv = rv*100 + bpf_setsockopt(skops, SOL_SOCKET, - SO_SNDBUF, &bufsize, - sizeof(bufsize)); - rv = rv*100 + bpf_setsockopt(skops, SOL_SOCKET, - SO_RCVBUF, &bufsize, - sizeof(bufsize)); + rv += bpf_setsockopt(skops, SOL_SOCKET, + SO_SNDBUF, &bufsize, + sizeof(bufsize)); + rv += bpf_setsockopt(skops, SOL_SOCKET, + SO_RCVBUF, &bufsize, + sizeof(bufsize)); break; default: rv = -1;