felix/bpf: fix err handling in bpf_program_attach_cgroup

As the error is encoded in the link pointer, it it not NULL in case of an error.
projectcalico · Jan 26, 2022 · bd9ec65 · bd9ec65
1 parent 00a16bf
commit bd9ec65
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/felix/bpf/libbpf/libbpf_api.h b/felix/bpf/libbpf/libbpf_api.h
@@ -139,8 +139,10 @@ struct bpf_link *bpf_program_attach_cgroup(struct bpf_object *obj, int cgroup_fd
 		goto out;
 	}
 
-	if (!(link = bpf_program__attach_cgroup(prog, cgroup_fd))) {
-		err = libbpf_get_error(link);
+	link = bpf_program__attach_cgroup(prog, cgroup_fd);
+	err = libbpf_get_error(link);
+	if (err) {
+		link = NULL;
 		goto out;
 	}