From 2c531639deb5e3ddfd6e8123b82052b2d9fbc6e5 Mon Sep 17 00:00:00 2001 From: Prankur Gupta Date: Tue, 17 Aug 2021 15:42:20 -0700 Subject: [PATCH] bpf: Add support for {set|get} socket options from setsockopt BPF Add logic to call bpf_setsockopt() and bpf_getsockopt() from setsockopt BPF programs. An example use case is when the user sets the IPV6_TCLASS socket option, we would also like to change the tcp-cc for that socket. We don't have any use case for calling bpf_setsockopt() from supposedly read- only sys_getsockopt(), so it is made available to BPF_CGROUP_SETSOCKOPT only at this point. Signed-off-by: Prankur Gupta Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20210817224221.3257826-2-prankgup@fb.com --- kernel/bpf/cgroup.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 9f35928..8e9d99e 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -1873,6 +1873,14 @@ cg_sockopt_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_sk_storage_get_proto; case BPF_FUNC_sk_storage_delete: return &bpf_sk_storage_delete_proto; + case BPF_FUNC_setsockopt: + if (prog->expected_attach_type == BPF_CGROUP_SETSOCKOPT) + return &bpf_sk_setsockopt_proto; + return NULL; + case BPF_FUNC_getsockopt: + if (prog->expected_attach_type == BPF_CGROUP_SETSOCKOPT) + return &bpf_sk_getsockopt_proto; + return NULL; #endif #ifdef CONFIG_INET case BPF_FUNC_tcp_sock: -- 2.7.4