[PATCH net-next v2 6/6] bpf: Fix tcp_clamp_kern.c sample program
From: Lawrence Brakmo <hidden>
Date: 2017-11-11 06:20:00
Subsystem:
bpf [general] (safe dynamic programs and tools), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
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 <redacted>
---
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 d68eadd9..f4225c9 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;
--
2.9.5