1 files changed, 384 insertions, 1 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c
index 59993fc9c0d7..21c5a37846ad 100644
--- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c
+++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c
@@ -3,7 +3,10 @@
 #include <test_progs.h>
 #include <network_helpers.h>
 #include "tailcall_poke.skel.h"
-
+#include "tailcall_bpf2bpf_hierarchy2.skel.h"
+#include "tailcall_bpf2bpf_hierarchy3.skel.h"
+#include "tailcall_freplace.skel.h"
+#include "tc_bpf2bpf.skel.h"
 
 /* test_tailcall_1 checks basic functionality by patching multiple locations
  * in a single program for a single tail call slot with nop->jmp, jmp->nop
@@ -1187,6 +1190,372 @@ out:
 	tailcall_poke__destroy(call);
 }
 
+static void test_tailcall_hierarchy_count(const char *which, bool test_fentry,
+					  bool test_fexit,
+					  bool test_fentry_entry)
+{
+	int err, map_fd, prog_fd, main_data_fd, fentry_data_fd, fexit_data_fd, i, val;
+	struct bpf_object *obj = NULL, *fentry_obj = NULL, *fexit_obj = NULL;
+	struct bpf_link *fentry_link = NULL, *fexit_link = NULL;
+	struct bpf_program *prog, *fentry_prog;
+	struct bpf_map *prog_array, *data_map;
+	int fentry_prog_fd;
+	char buff[128] = {};
+
+	LIBBPF_OPTS(bpf_test_run_opts, topts,
+		.data_in = buff,
+		.data_size_in = sizeof(buff),
+		.repeat = 1,
+	);
+
+	err = bpf_prog_test_load(which, BPF_PROG_TYPE_SCHED_CLS, &obj,
+				 &prog_fd);
+	if (!ASSERT_OK(err, "load obj"))
+		return;
+
+	prog = bpf_object__find_program_by_name(obj, "entry");
+	if (!ASSERT_OK_PTR(prog, "find entry prog"))
+		goto out;
+
+	prog_fd = bpf_program__fd(prog);
+	if (!ASSERT_GE(prog_fd, 0, "prog_fd"))
+		goto out;
+
+	if (test_fentry_entry) {
+		fentry_obj = bpf_object__open_file("tailcall_bpf2bpf_hierarchy_fentry.bpf.o",
+						   NULL);
+		if (!ASSERT_OK_PTR(fentry_obj, "open fentry_obj file"))
+			goto out;
+
+		fentry_prog = bpf_object__find_program_by_name(fentry_obj,
+							       "fentry");
+		if (!ASSERT_OK_PTR(prog, "find fentry prog"))
+			goto out;
+
+		err = bpf_program__set_attach_target(fentry_prog, prog_fd,
+						     "entry");
+		if (!ASSERT_OK(err, "set_attach_target entry"))
+			goto out;
+
+		err = bpf_object__load(fentry_obj);
+		if (!ASSERT_OK(err, "load fentry_obj"))
+			goto out;
+
+		fentry_link = bpf_program__attach_trace(fentry_prog);
+		if (!ASSERT_OK_PTR(fentry_link, "attach_trace"))
+			goto out;
+
+		fentry_prog_fd = bpf_program__fd(fentry_prog);
+		if (!ASSERT_GE(fentry_prog_fd, 0, "fentry_prog_fd"))
+			goto out;
+
+		prog_array = bpf_object__find_map_by_name(fentry_obj, "jmp_table");
+		if (!ASSERT_OK_PTR(prog_array, "find jmp_table"))
+			goto out;
+
+		map_fd = bpf_map__fd(prog_array);
+		if (!ASSERT_GE(map_fd, 0, "map_fd"))
+			goto out;
+
+		i = 0;
+		err = bpf_map_update_elem(map_fd, &i, &fentry_prog_fd, BPF_ANY);
+		if (!ASSERT_OK(err, "update jmp_table"))
+			goto out;
+
+		data_map = bpf_object__find_map_by_name(fentry_obj, ".bss");
+		if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
+				  "find data_map"))
+			goto out;
+
+	} else {
+		prog_array = bpf_object__find_map_by_name(obj, "jmp_table");
+		if (!ASSERT_OK_PTR(prog_array, "find jmp_table"))
+			goto out;
+
+		map_fd = bpf_map__fd(prog_array);
+		if (!ASSERT_GE(map_fd, 0, "map_fd"))
+			goto out;
+
+		i = 0;
+		err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+		if (!ASSERT_OK(err, "update jmp_table"))
+			goto out;
+
+		data_map = bpf_object__find_map_by_name(obj, ".bss");
+		if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
+				  "find data_map"))
+			goto out;
+	}
+
+	if (test_fentry) {
+		fentry_obj = bpf_object__open_file("tailcall_bpf2bpf_fentry.bpf.o",
+						   NULL);
+		if (!ASSERT_OK_PTR(fentry_obj, "open fentry_obj file"))
+			goto out;
+
+		prog = bpf_object__find_program_by_name(fentry_obj, "fentry");
+		if (!ASSERT_OK_PTR(prog, "find fentry prog"))
+			goto out;
+
+		err = bpf_program__set_attach_target(prog, prog_fd,
+						     "subprog_tail");
+		if (!ASSERT_OK(err, "set_attach_target subprog_tail"))
+			goto out;
+
+		err = bpf_object__load(fentry_obj);
+		if (!ASSERT_OK(err, "load fentry_obj"))
+			goto out;
+
+		fentry_link = bpf_program__attach_trace(prog);
+		if (!ASSERT_OK_PTR(fentry_link, "attach_trace"))
+			goto out;
+	}
+
+	if (test_fexit) {
+		fexit_obj = bpf_object__open_file("tailcall_bpf2bpf_fexit.bpf.o",
+						  NULL);
+		if (!ASSERT_OK_PTR(fexit_obj, "open fexit_obj file"))
+			goto out;
+
+		prog = bpf_object__find_program_by_name(fexit_obj, "fexit");
+		if (!ASSERT_OK_PTR(prog, "find fexit prog"))
+			goto out;
+
+		err = bpf_program__set_attach_target(prog, prog_fd,
+						     "subprog_tail");
+		if (!ASSERT_OK(err, "set_attach_target subprog_tail"))
+			goto out;
+
+		err = bpf_object__load(fexit_obj);
+		if (!ASSERT_OK(err, "load fexit_obj"))
+			goto out;
+
+		fexit_link = bpf_program__attach_trace(prog);
+		if (!ASSERT_OK_PTR(fexit_link, "attach_trace"))
+			goto out;
+	}
+
+	err = bpf_prog_test_run_opts(prog_fd, &topts);
+	ASSERT_OK(err, "tailcall");
+	ASSERT_EQ(topts.retval, 1, "tailcall retval");
+
+	main_data_fd = bpf_map__fd(data_map);
+	if (!ASSERT_GE(main_data_fd, 0, "main_data_fd"))
+		goto out;
+
+	i = 0;
+	err = bpf_map_lookup_elem(main_data_fd, &i, &val);
+	ASSERT_OK(err, "tailcall count");
+	ASSERT_EQ(val, 34, "tailcall count");
+
+	if (test_fentry) {
+		data_map = bpf_object__find_map_by_name(fentry_obj, ".bss");
+		if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
+				  "find tailcall_bpf2bpf_fentry.bss map"))
+			goto out;
+
+		fentry_data_fd = bpf_map__fd(data_map);
+		if (!ASSERT_GE(fentry_data_fd, 0,
+				  "find tailcall_bpf2bpf_fentry.bss map fd"))
+			goto out;
+
+		i = 0;
+		err = bpf_map_lookup_elem(fentry_data_fd, &i, &val);
+		ASSERT_OK(err, "fentry count");
+		ASSERT_EQ(val, 68, "fentry count");
+	}
+
+	if (test_fexit) {
+		data_map = bpf_object__find_map_by_name(fexit_obj, ".bss");
+		if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
+				  "find tailcall_bpf2bpf_fexit.bss map"))
+			goto out;
+
+		fexit_data_fd = bpf_map__fd(data_map);
+		if (!ASSERT_GE(fexit_data_fd, 0,
+				  "find tailcall_bpf2bpf_fexit.bss map fd"))
+			goto out;
+
+		i = 0;
+		err = bpf_map_lookup_elem(fexit_data_fd, &i, &val);
+		ASSERT_OK(err, "fexit count");
+		ASSERT_EQ(val, 68, "fexit count");
+	}
+
+	i = 0;
+	err = bpf_map_delete_elem(map_fd, &i);
+	if (!ASSERT_OK(err, "delete_elem from jmp_table"))
+		goto out;
+
+	err = bpf_prog_test_run_opts(prog_fd, &topts);
+	ASSERT_OK(err, "tailcall");
+	ASSERT_EQ(topts.retval, 1, "tailcall retval");
+
+	i = 0;
+	err = bpf_map_lookup_elem(main_data_fd, &i, &val);
+	ASSERT_OK(err, "tailcall count");
+	ASSERT_EQ(val, 35, "tailcall count");
+
+	if (test_fentry) {
+		i = 0;
+		err = bpf_map_lookup_elem(fentry_data_fd, &i, &val);
+		ASSERT_OK(err, "fentry count");
+		ASSERT_EQ(val, 70, "fentry count");
+	}
+
+	if (test_fexit) {
+		i = 0;
+		err = bpf_map_lookup_elem(fexit_data_fd, &i, &val);
+		ASSERT_OK(err, "fexit count");
+		ASSERT_EQ(val, 70, "fexit count");
+	}
+
+out:
+	bpf_link__destroy(fentry_link);
+	bpf_link__destroy(fexit_link);
+	bpf_object__close(fentry_obj);
+	bpf_object__close(fexit_obj);
+	bpf_object__close(obj);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_1 checks that the count value of the tail
+ * call limit enforcement matches with expectations when tailcalls are preceded
+ * with two bpf2bpf calls.
+ *
+ *         subprog --tailcall-> entry
+ * entry <
+ *         subprog --tailcall-> entry
+ */
+static void test_tailcall_bpf2bpf_hierarchy_1(void)
+{
+	test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
+				      false, false, false);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_fentry checks that the count value of the
+ * tail call limit enforcement matches with expectations when tailcalls are
+ * preceded with two bpf2bpf calls, and the two subprogs are traced by fentry.
+ */
+static void test_tailcall_bpf2bpf_hierarchy_fentry(void)
+{
+	test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
+				      true, false, false);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_fexit checks that the count value of the tail
+ * call limit enforcement matches with expectations when tailcalls are preceded
+ * with two bpf2bpf calls, and the two subprogs are traced by fexit.
+ */
+static void test_tailcall_bpf2bpf_hierarchy_fexit(void)
+{
+	test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
+				      false, true, false);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_fentry_fexit checks that the count value of
+ * the tail call limit enforcement matches with expectations when tailcalls are
+ * preceded with two bpf2bpf calls, and the two subprogs are traced by both
+ * fentry and fexit.
+ */
+static void test_tailcall_bpf2bpf_hierarchy_fentry_fexit(void)
+{
+	test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
+				      true, true, false);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_fentry_entry checks that the count value of
+ * the tail call limit enforcement matches with expectations when tailcalls are
+ * preceded with two bpf2bpf calls in fentry.
+ */
+static void test_tailcall_bpf2bpf_hierarchy_fentry_entry(void)
+{
+	test_tailcall_hierarchy_count("tc_dummy.bpf.o", false, false, true);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_2 checks that the count value of the tail
+ * call limit enforcement matches with expectations:
+ *
+ *         subprog_tail0 --tailcall-> classifier_0 -> subprog_tail0
+ * entry <
+ *         subprog_tail1 --tailcall-> classifier_1 -> subprog_tail1
+ */
+static void test_tailcall_bpf2bpf_hierarchy_2(void)
+{
+	RUN_TESTS(tailcall_bpf2bpf_hierarchy2);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_3 checks that the count value of the tail
+ * call limit enforcement matches with expectations:
+ *
+ *                                   subprog with jmp_table0 to classifier_0
+ * entry --tailcall-> classifier_0 <
+ *                                   subprog with jmp_table1 to classifier_0
+ */
+static void test_tailcall_bpf2bpf_hierarchy_3(void)
+{
+	RUN_TESTS(tailcall_bpf2bpf_hierarchy3);
+}
+
+/* test_tailcall_freplace checks that the attached freplace prog is OK to
+ * update the prog_array map.
+ */
+static void test_tailcall_freplace(void)
+{
+	struct tailcall_freplace *freplace_skel = NULL;
+	struct bpf_link *freplace_link = NULL;
+	struct bpf_program *freplace_prog;
+	struct tc_bpf2bpf *tc_skel = NULL;
+	int prog_fd, map_fd;
+	char buff[128] = {};
+	int err, key;
+
+	LIBBPF_OPTS(bpf_test_run_opts, topts,
+		    .data_in = buff,
+		    .data_size_in = sizeof(buff),
+		    .repeat = 1,
+	);
+
+	freplace_skel = tailcall_freplace__open();
+	if (!ASSERT_OK_PTR(freplace_skel, "tailcall_freplace__open"))
+		return;
+
+	tc_skel = tc_bpf2bpf__open_and_load();
+	if (!ASSERT_OK_PTR(tc_skel, "tc_bpf2bpf__open_and_load"))
+		goto out;
+
+	prog_fd = bpf_program__fd(tc_skel->progs.entry_tc);
+	freplace_prog = freplace_skel->progs.entry_freplace;
+	err = bpf_program__set_attach_target(freplace_prog, prog_fd, "subprog");
+	if (!ASSERT_OK(err, "set_attach_target"))
+		goto out;
+
+	err = tailcall_freplace__load(freplace_skel);
+	if (!ASSERT_OK(err, "tailcall_freplace__load"))
+		goto out;
+
+	freplace_link = bpf_program__attach_freplace(freplace_prog, prog_fd,
+						     "subprog");
+	if (!ASSERT_OK_PTR(freplace_link, "attach_freplace"))
+		goto out;
+
+	map_fd = bpf_map__fd(freplace_skel->maps.jmp_table);
+	prog_fd = bpf_program__fd(freplace_prog);
+	key = 0;
+	err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY);
+	if (!ASSERT_OK(err, "update jmp_table"))
+		goto out;
+
+	prog_fd = bpf_program__fd(tc_skel->progs.entry_tc);
+	err = bpf_prog_test_run_opts(prog_fd, &topts);
+	ASSERT_OK(err, "test_run");
+	ASSERT_EQ(topts.retval, 34, "test_run retval");
+
+out:
+	bpf_link__destroy(freplace_link);
+	tc_bpf2bpf__destroy(tc_skel);
+	tailcall_freplace__destroy(freplace_skel);
+}
+
 void test_tailcalls(void)
 {
 	if (test__start_subtest("tailcall_1"))
@@ -1223,4 +1592,18 @@ void test_tailcalls(void)
 		test_tailcall_bpf2bpf_fentry_entry();
 	if (test__start_subtest("tailcall_poke"))
 		test_tailcall_poke();
+	if (test__start_subtest("tailcall_bpf2bpf_hierarchy_1"))
+		test_tailcall_bpf2bpf_hierarchy_1();
+	if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fentry"))
+		test_tailcall_bpf2bpf_hierarchy_fentry();
+	if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fexit"))
+		test_tailcall_bpf2bpf_hierarchy_fexit();
+	if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fentry_fexit"))
+		test_tailcall_bpf2bpf_hierarchy_fentry_fexit();
+	if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fentry_entry"))
+		test_tailcall_bpf2bpf_hierarchy_fentry_entry();
+	test_tailcall_bpf2bpf_hierarchy_2();
+	test_tailcall_bpf2bpf_hierarchy_3();
+	if (test__start_subtest("tailcall_freplace"))
+		test_tailcall_freplace();
 }