bpf: Expose socket storage to BPF_PROG_TYPE_CGROUP_SOCK
This lets us use socket storage from the following hooks:
* BPF_CGROUP_INET_SOCK_CREATE
* BPF_CGROUP_INET_SOCK_RELEASE
* BPF_CGROUP_INET4_POST_BIND
* BPF_CGROUP_INET6_POST_BIND
Using existing 'bpf_sk_storage_get_proto' doesn't work because
second argument is ARG_PTR_TO_SOCKET. Even though
BPF_PROG_TYPE_CGROUP_SOCK hooks operate on 'struct bpf_sock',
the verifier still considers it as a PTR_TO_CTX.
That's why I'm adding another 'bpf_sk_storage_get_cg_sock_proto'
definition strictly for BPF_PROG_TYPE_CGROUP_SOCK which accepts
ARG_PTR_TO_CTX which is really 'struct sock' for this program type.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200729003104.1280813-1-sdf@google.com
diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
index eafcd15..d3377c9 100644
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -944,6 +944,16 @@ const struct bpf_func_proto bpf_sk_storage_get_proto = {
.arg4_type = ARG_ANYTHING,
};
+const struct bpf_func_proto bpf_sk_storage_get_cg_sock_proto = {
+ .func = bpf_sk_storage_get,
+ .gpl_only = false,
+ .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_CTX, /* context is 'struct sock' */
+ .arg3_type = ARG_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg4_type = ARG_ANYTHING,
+};
+
const struct bpf_func_proto bpf_sk_storage_delete_proto = {
.func = bpf_sk_storage_delete,
.gpl_only = false,
