1 files changed, 333 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/sockopt_multi.c b/tools/testing/selftests/bpf/prog_tests/sockopt_multi.c
new file mode 100644
index 000000000..7f5659349
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/sockopt_multi.c
@@ -0,0 +1,333 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+#include "cgroup_helpers.h"
+
+static int prog_attach(struct bpf_object *obj, int cgroup_fd, const char *title, const char *name)
+{
+	enum bpf_attach_type attach_type;
+	enum bpf_prog_type prog_type;
+	struct bpf_program *prog;
+	int err;
+
+	err = libbpf_prog_type_by_name(title, &prog_type, &attach_type);
+	if (err) {
+		log_err("Failed to deduct types for %s BPF program", title);
+		return -1;
+	}
+
+	prog = bpf_object__find_program_by_name(obj, name);
+	if (!prog) {
+		log_err("Failed to find %s BPF program", name);
+		return -1;
+	}
+
+	err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd,
+			      attach_type, BPF_F_ALLOW_MULTI);
+	if (err) {
+		log_err("Failed to attach %s BPF program", name);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int prog_detach(struct bpf_object *obj, int cgroup_fd, const char *title, const char *name)
+{
+	enum bpf_attach_type attach_type;
+	enum bpf_prog_type prog_type;
+	struct bpf_program *prog;
+	int err;
+
+	err = libbpf_prog_type_by_name(title, &prog_type, &attach_type);
+	if (err)
+		return -1;
+
+	prog = bpf_object__find_program_by_name(obj, name);
+	if (!prog)
+		return -1;
+
+	err = bpf_prog_detach2(bpf_program__fd(prog), cgroup_fd,
+			       attach_type);
+	if (err)
+		return -1;
+
+	return 0;
+}
+
+static int run_getsockopt_test(struct bpf_object *obj, int cg_parent,
+			       int cg_child, int sock_fd)
+{
+	socklen_t optlen;
+	__u8 buf;
+	int err;
+
+	/* Set IP_TOS to the expected value (0x80). */
+
+	buf = 0x80;
+	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+	if (err < 0) {
+		log_err("Failed to call setsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (err) {
+		log_err("Failed to call getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	if (buf != 0x80) {
+		log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf);
+		err = -1;
+		goto detach;
+	}
+
+	/* Attach child program and make sure it returns new value:
+	 * - kernel:      -> 0x80
+	 * - child:  0x80 -> 0x90
+	 */
+
+	err = prog_attach(obj, cg_child, "cgroup/getsockopt", "_getsockopt_child");
+	if (err)
+		goto detach;
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (err) {
+		log_err("Failed to call getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	if (buf != 0x90) {
+		log_err("Unexpected getsockopt 0x%x != 0x90", buf);
+		err = -1;
+		goto detach;
+	}
+
+	/* Attach parent program and make sure it returns new value:
+	 * - kernel:      -> 0x80
+	 * - child:  0x80 -> 0x90
+	 * - parent: 0x90 -> 0xA0
+	 */
+
+	err = prog_attach(obj, cg_parent, "cgroup/getsockopt", "_getsockopt_parent");
+	if (err)
+		goto detach;
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (err) {
+		log_err("Failed to call getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	if (buf != 0xA0) {
+		log_err("Unexpected getsockopt 0x%x != 0xA0", buf);
+		err = -1;
+		goto detach;
+	}
+
+	/* Setting unexpected initial sockopt should return EPERM:
+	 * - kernel: -> 0x40
+	 * - child:  unexpected 0x40, EPERM
+	 * - parent: unexpected 0x40, EPERM
+	 */
+
+	buf = 0x40;
+	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+	if (err < 0) {
+		log_err("Failed to call setsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (!err) {
+		log_err("Unexpected success from getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	/* Detach child program and make sure we still get EPERM:
+	 * - kernel: -> 0x40
+	 * - parent: unexpected 0x40, EPERM
+	 */
+
+	err = prog_detach(obj, cg_child, "cgroup/getsockopt", "_getsockopt_child");
+	if (err) {
+		log_err("Failed to detach child program");
+		goto detach;
+	}
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (!err) {
+		log_err("Unexpected success from getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	/* Set initial value to the one the parent program expects:
+	 * - kernel:      -> 0x90
+	 * - parent: 0x90 -> 0xA0
+	 */
+
+	buf = 0x90;
+	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+	if (err < 0) {
+		log_err("Failed to call setsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (err) {
+		log_err("Failed to call getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	if (buf != 0xA0) {
+		log_err("Unexpected getsockopt 0x%x != 0xA0", buf);
+		err = -1;
+		goto detach;
+	}
+
+detach:
+	prog_detach(obj, cg_child, "cgroup/getsockopt", "_getsockopt_child");
+	prog_detach(obj, cg_parent, "cgroup/getsockopt", "_getsockopt_parent");
+
+	return err;
+}
+
+static int run_setsockopt_test(struct bpf_object *obj, int cg_parent,
+			       int cg_child, int sock_fd)
+{
+	socklen_t optlen;
+	__u8 buf;
+	int err;
+
+	/* Set IP_TOS to the expected value (0x80). */
+
+	buf = 0x80;
+	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+	if (err < 0) {
+		log_err("Failed to call setsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (err) {
+		log_err("Failed to call getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	if (buf != 0x80) {
+		log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf);
+		err = -1;
+		goto detach;
+	}
+
+	/* Attach child program and make sure it adds 0x10. */
+
+	err = prog_attach(obj, cg_child, "cgroup/setsockopt", "_setsockopt");
+	if (err)
+		goto detach;
+
+	buf = 0x80;
+	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+	if (err < 0) {
+		log_err("Failed to call setsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (err) {
+		log_err("Failed to call getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	if (buf != 0x80 + 0x10) {
+		log_err("Unexpected getsockopt 0x%x != 0x80 + 0x10", buf);
+		err = -1;
+		goto detach;
+	}
+
+	/* Attach parent program and make sure it adds another 0x10. */
+
+	err = prog_attach(obj, cg_parent, "cgroup/setsockopt", "_setsockopt");
+	if (err)
+		goto detach;
+
+	buf = 0x80;
+	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+	if (err < 0) {
+		log_err("Failed to call setsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	buf = 0x00;
+	optlen = 1;
+	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+	if (err) {
+		log_err("Failed to call getsockopt(IP_TOS)");
+		goto detach;
+	}
+
+	if (buf != 0x80 + 2 * 0x10) {
+		log_err("Unexpected getsockopt 0x%x != 0x80 + 2 * 0x10", buf);
+		err = -1;
+		goto detach;
+	}
+
+detach:
+	prog_detach(obj, cg_child, "cgroup/setsockopt", "_setsockopt");
+	prog_detach(obj, cg_parent, "cgroup/setsockopt", "_setsockopt");
+
+	return err;
+}
+
+void test_sockopt_multi(void)
+{
+	int cg_parent = -1, cg_child = -1;
+	struct bpf_object *obj = NULL;
+	int sock_fd = -1;
+	int err = -1;
+
+	cg_parent = test__join_cgroup("/parent");
+	if (!ASSERT_GE(cg_parent, 0, "join_cgroup /parent"))
+		goto out;
+
+	cg_child = test__join_cgroup("/parent/child");
+	if (!ASSERT_GE(cg_child, 0, "join_cgroup /parent/child"))
+		goto out;
+
+	obj = bpf_object__open_file("sockopt_multi.bpf.o", NULL);
+	if (!ASSERT_OK_PTR(obj, "obj_load"))
+		goto out;
+
+	err = bpf_object__load(obj);
+	if (!ASSERT_OK(err, "obj_load"))
+		goto out;
+
+	sock_fd = socket(AF_INET, SOCK_STREAM, 0);
+	if (!ASSERT_GE(sock_fd, 0, "socket"))
+		goto out;
+
+	ASSERT_OK(run_getsockopt_test(obj, cg_parent, cg_child, sock_fd), "getsockopt_test");
+	ASSERT_OK(run_setsockopt_test(obj, cg_parent, cg_child, sock_fd), "setsockopt_test");
+
+out:
+	close(sock_fd);
+	bpf_object__close(obj);
+	close(cg_child);
+	close(cg_parent);
+}