1 files changed, 96 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/subprogs.c b/tools/testing/selftests/bpf/prog_tests/subprogs.c
new file mode 100644
index 000000000000..903f35a9e62e
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/subprogs.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+#include <test_progs.h>
+#include "test_subprogs.skel.h"
+#include "test_subprogs_unused.skel.h"
+
+struct toggler_ctx {
+	int fd;
+	bool stop;
+};
+
+static void *toggle_jit_harden(void *arg)
+{
+	struct toggler_ctx *ctx = arg;
+	char two = '2';
+	char zero = '0';
+
+	while (!ctx->stop) {
+		lseek(ctx->fd, SEEK_SET, 0);
+		write(ctx->fd, &two, sizeof(two));
+		lseek(ctx->fd, SEEK_SET, 0);
+		write(ctx->fd, &zero, sizeof(zero));
+	}
+
+	return NULL;
+}
+
+static void test_subprogs_with_jit_harden_toggling(void)
+{
+	struct toggler_ctx ctx;
+	pthread_t toggler;
+	int err;
+	unsigned int i, loop = 10;
+
+	ctx.fd = open("/proc/sys/net/core/bpf_jit_harden", O_RDWR);
+	if (!ASSERT_GE(ctx.fd, 0, "open bpf_jit_harden"))
+		return;
+
+	ctx.stop = false;
+	err = pthread_create(&toggler, NULL, toggle_jit_harden, &ctx);
+	if (!ASSERT_OK(err, "new toggler"))
+		goto out;
+
+	/* Make toggler thread to run */
+	usleep(1);
+
+	for (i = 0; i < loop; i++) {
+		struct test_subprogs *skel = test_subprogs__open_and_load();
+
+		if (!ASSERT_OK_PTR(skel, "skel open"))
+			break;
+		test_subprogs__destroy(skel);
+	}
+
+	ctx.stop = true;
+	pthread_join(toggler, NULL);
+out:
+	close(ctx.fd);
+}
+
+static void test_subprogs_alone(void)
+{
+	struct test_subprogs *skel;
+	struct test_subprogs_unused *skel2;
+	int err;
+
+	skel = test_subprogs__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "skel_open"))
+		return;
+
+	err = test_subprogs__attach(skel);
+	if (!ASSERT_OK(err, "skel attach"))
+		goto cleanup;
+
+	usleep(1);
+
+	ASSERT_EQ(skel->bss->res1, 12, "res1");
+	ASSERT_EQ(skel->bss->res2, 17, "res2");
+	ASSERT_EQ(skel->bss->res3, 19, "res3");
+	ASSERT_EQ(skel->bss->res4, 36, "res4");
+
+	skel2 = test_subprogs_unused__open_and_load();
+	ASSERT_OK_PTR(skel2, "unused_progs_skel");
+	test_subprogs_unused__destroy(skel2);
+
+cleanup:
+	test_subprogs__destroy(skel);
+}
+
+void test_subprogs(void)
+{
+	if (test__start_subtest("subprogs_alone"))
+		test_subprogs_alone();
+	if (test__start_subtest("subprogs_and_jit_harden"))
+		test_subprogs_with_jit_harden_toggling();
+}