1 files changed, 65 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/string_kfuncs.c b/tools/testing/selftests/bpf/prog_tests/string_kfuncs.c
new file mode 100644
index 000000000000..35af8044d059
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/string_kfuncs.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2025 Red Hat, Inc.*/
+#include <test_progs.h>
+#include "string_kfuncs_success.skel.h"
+#include "string_kfuncs_failure1.skel.h"
+#include "string_kfuncs_failure2.skel.h"
+#include <sys/mman.h>
+
+static const char * const test_cases[] = {
+	"strcmp",
+	"strchr",
+	"strchrnul",
+	"strnchr",
+	"strrchr",
+	"strlen",
+	"strnlen",
+	"strspn_str",
+	"strspn_accept",
+	"strcspn_str",
+	"strcspn_reject",
+	"strstr",
+	"strnstr",
+};
+
+void run_too_long_tests(void)
+{
+	struct string_kfuncs_failure2 *skel;
+	struct bpf_program *prog;
+	char test_name[256];
+	int err, i;
+
+	skel = string_kfuncs_failure2__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "string_kfuncs_failure2__open_and_load"))
+		return;
+
+	memset(skel->bss->long_str, 'a', sizeof(skel->bss->long_str));
+
+	for (i = 0; i < ARRAY_SIZE(test_cases); i++) {
+		sprintf(test_name, "test_%s_too_long", test_cases[i]);
+		if (!test__start_subtest(test_name))
+			continue;
+
+		prog = bpf_object__find_program_by_name(skel->obj, test_name);
+		if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
+			goto cleanup;
+
+		LIBBPF_OPTS(bpf_test_run_opts, topts);
+		err = bpf_prog_test_run_opts(bpf_program__fd(prog), &topts);
+		if (!ASSERT_OK(err, "bpf_prog_test_run"))
+			goto cleanup;
+
+		ASSERT_EQ(topts.retval, -E2BIG, "reading too long string fails with -E2BIG");
+	}
+
+cleanup:
+	string_kfuncs_failure2__destroy(skel);
+}
+
+void test_string_kfuncs(void)
+{
+	RUN_TESTS(string_kfuncs_success);
+	RUN_TESTS(string_kfuncs_failure1);
+
+	run_too_long_tests();
+}