// SPDX-License-Identifier: GPL-2.0 #include <test_progs.h> #include <network_helpers.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 * and jmp->jmp rewrites. Also checks for nop->nop. */ static void test_tailcall_1(void) { int err, map_fd, prog_fd, main_fd, i, j; struct bpf_map *prog_array; struct bpf_program *prog; struct bpf_object *obj; char prog_name[32]; 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("tailcall1.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } for (i = 0; i < bpf_map__max_entries(prog_array); i++) { err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, i, "tailcall retval"); err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; } err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 3, "tailcall retval"); for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_OK(topts.retval, "tailcall retval"); for (i = 0; i < bpf_map__max_entries(prog_array); i++) { j = bpf_map__max_entries(prog_array) - 1 - i; snprintf(prog_name, sizeof(prog_name), "classifier_%d", j); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } for (i = 0; i < bpf_map__max_entries(prog_array); i++) { j = bpf_map__max_entries(prog_array) - 1 - i; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, j, "tailcall retval"); err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; } err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 3, "tailcall retval"); for (i = 0; i < bpf_map__max_entries(prog_array); i++) { err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err >= 0 || errno != ENOENT)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 3, "tailcall retval"); } out: bpf_object__close(obj); } /* test_tailcall_2 checks that patching multiple programs for a single * tail call slot works. It also jumps through several programs and tests * the tail call limit counter. */ static void test_tailcall_2(void) { int err, map_fd, prog_fd, main_fd, i; struct bpf_map *prog_array; struct bpf_program *prog; struct bpf_object *obj; char prog_name[32]; 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("tailcall2.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 2, "tailcall retval"); i = 2; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 1, "tailcall retval"); i = 0; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 3, "tailcall retval"); out: bpf_object__close(obj); } static void test_tailcall_count(const char *which) { int err, map_fd, prog_fd, main_fd, data_fd, i, val; struct bpf_map *prog_array, *data_map; struct bpf_program *prog; struct bpf_object *obj; 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 (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; prog = bpf_object__find_program_by_name(obj, "classifier_0"); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; i = 0; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 1, "tailcall retval"); data_map = bpf_object__find_map_by_name(obj, "tailcall.bss"); if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map))) return; data_fd = bpf_map__fd(data_map); if (CHECK_FAIL(map_fd < 0)) return; i = 0; err = bpf_map_lookup_elem(data_fd, &i, &val); ASSERT_OK(err, "tailcall count"); ASSERT_EQ(val, 33, "tailcall count"); i = 0; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_OK(topts.retval, "tailcall retval"); out: bpf_object__close(obj); } /* test_tailcall_3 checks that the count value of the tail call limit * enforcement matches with expectations. JIT uses direct jump. */ static void test_tailcall_3(void) { test_tailcall_count("tailcall3.bpf.o"); } /* test_tailcall_6 checks that the count value of the tail call limit * enforcement matches with expectations. JIT uses indirect jump. */ static void test_tailcall_6(void) { test_tailcall_count("tailcall6.bpf.o"); } /* test_tailcall_4 checks that the kernel properly selects indirect jump * for the case where the key is not known. Latter is passed via global * data to select different targets we can compare return value of. */ static void test_tailcall_4(void) { int err, map_fd, prog_fd, main_fd, data_fd, i; struct bpf_map *prog_array, *data_map; struct bpf_program *prog; struct bpf_object *obj; static const int zero = 0; char buff[128] = {}; char prog_name[32]; LIBBPF_OPTS(bpf_test_run_opts, topts, .data_in = buff, .data_size_in = sizeof(buff), .repeat = 1, ); err = bpf_prog_test_load("tailcall4.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; data_map = bpf_object__find_map_by_name(obj, "tailcall.bss"); if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map))) return; data_fd = bpf_map__fd(data_map); if (CHECK_FAIL(map_fd < 0)) return; for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } for (i = 0; i < bpf_map__max_entries(prog_array); i++) { err = bpf_map_update_elem(data_fd, &zero, &i, BPF_ANY); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, i, "tailcall retval"); } for (i = 0; i < bpf_map__max_entries(prog_array); i++) { err = bpf_map_update_elem(data_fd, &zero, &i, BPF_ANY); if (CHECK_FAIL(err)) goto out; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 3, "tailcall retval"); } out: bpf_object__close(obj); } /* test_tailcall_5 probes similarly to test_tailcall_4 that the kernel generates * an indirect jump when the keys are const but different from different branches. */ static void test_tailcall_5(void) { int err, map_fd, prog_fd, main_fd, data_fd, i, key[] = { 1111, 1234, 5678 }; struct bpf_map *prog_array, *data_map; struct bpf_program *prog; struct bpf_object *obj; static const int zero = 0; char buff[128] = {}; char prog_name[32]; LIBBPF_OPTS(bpf_test_run_opts, topts, .data_in = buff, .data_size_in = sizeof(buff), .repeat = 1, ); err = bpf_prog_test_load("tailcall5.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; data_map = bpf_object__find_map_by_name(obj, "tailcall.bss"); if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map))) return; data_fd = bpf_map__fd(data_map); if (CHECK_FAIL(map_fd < 0)) return; for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } for (i = 0; i < bpf_map__max_entries(prog_array); i++) { err = bpf_map_update_elem(data_fd, &zero, &key[i], BPF_ANY); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, i, "tailcall retval"); } for (i = 0; i < bpf_map__max_entries(prog_array); i++) { err = bpf_map_update_elem(data_fd, &zero, &key[i], BPF_ANY); if (CHECK_FAIL(err)) goto out; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 3, "tailcall retval"); } out: bpf_object__close(obj); } /* test_tailcall_bpf2bpf_1 purpose is to make sure that tailcalls are working * correctly in correlation with BPF subprograms */ static void test_tailcall_bpf2bpf_1(void) { int err, map_fd, prog_fd, main_fd, i; struct bpf_map *prog_array; struct bpf_program *prog; struct bpf_object *obj; char prog_name[32]; LIBBPF_OPTS(bpf_test_run_opts, topts, .data_in = &pkt_v4, .data_size_in = sizeof(pkt_v4), .repeat = 1, ); err = bpf_prog_test_load("tailcall_bpf2bpf1.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; /* nop -> jmp */ for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 1, "tailcall retval"); /* jmp -> nop, call subprog that will do tailcall */ i = 1; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_OK(topts.retval, "tailcall retval"); /* make sure that subprog can access ctx and entry prog that * called this subprog can properly return */ i = 0; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, sizeof(pkt_v4) * 2, "tailcall retval"); out: bpf_object__close(obj); } /* test_tailcall_bpf2bpf_2 checks that the count value of the tail call limit * enforcement matches with expectations when tailcall is preceded with * bpf2bpf call. */ static void test_tailcall_bpf2bpf_2(void) { int err, map_fd, prog_fd, main_fd, data_fd, i, val; struct bpf_map *prog_array, *data_map; struct bpf_program *prog; struct bpf_object *obj; 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("tailcall_bpf2bpf2.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; prog = bpf_object__find_program_by_name(obj, "classifier_0"); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; i = 0; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 1, "tailcall retval"); data_map = bpf_object__find_map_by_name(obj, "tailcall.bss"); if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map))) return; data_fd = bpf_map__fd(data_map); if (CHECK_FAIL(map_fd < 0)) return; i = 0; err = bpf_map_lookup_elem(data_fd, &i, &val); ASSERT_OK(err, "tailcall count"); ASSERT_EQ(val, 33, "tailcall count"); i = 0; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_OK(topts.retval, "tailcall retval"); out: bpf_object__close(obj); } /* test_tailcall_bpf2bpf_3 checks that non-trivial amount of stack (up to * 256 bytes) can be used within bpf subprograms that have the tailcalls * in them */ static void test_tailcall_bpf2bpf_3(void) { int err, map_fd, prog_fd, main_fd, i; struct bpf_map *prog_array; struct bpf_program *prog; struct bpf_object *obj; char prog_name[32]; LIBBPF_OPTS(bpf_test_run_opts, topts, .data_in = &pkt_v4, .data_size_in = sizeof(pkt_v4), .repeat = 1, ); err = bpf_prog_test_load("tailcall_bpf2bpf3.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, sizeof(pkt_v4) * 3, "tailcall retval"); i = 1; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, sizeof(pkt_v4), "tailcall retval"); i = 0; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, sizeof(pkt_v4) * 2, "tailcall retval"); out: bpf_object__close(obj); } #include "tailcall_bpf2bpf4.skel.h" /* test_tailcall_bpf2bpf_4 checks that tailcall counter is correctly preserved * across tailcalls combined with bpf2bpf calls. for making sure that tailcall * counter behaves correctly, bpf program will go through following flow: * * entry -> entry_subprog -> tailcall0 -> bpf_func0 -> subprog0 -> * -> tailcall1 -> bpf_func1 -> subprog1 -> tailcall2 -> bpf_func2 -> * subprog2 [here bump global counter] --------^ * * We go through first two tailcalls and start counting from the subprog2 where * the loop begins. At the end of the test make sure that the global counter is * equal to 31, because tailcall counter includes the first two tailcalls * whereas global counter is incremented only on loop presented on flow above. * * The noise parameter is used to insert bpf_map_update calls into the logic * to force verifier to patch instructions. This allows us to ensure jump * logic remains correct with instruction movement. */ static void test_tailcall_bpf2bpf_4(bool noise) { int err, map_fd, prog_fd, main_fd, data_fd, i; struct tailcall_bpf2bpf4__bss val; struct bpf_map *prog_array, *data_map; struct bpf_program *prog; struct bpf_object *obj; char prog_name[32]; LIBBPF_OPTS(bpf_test_run_opts, topts, .data_in = &pkt_v4, .data_size_in = sizeof(pkt_v4), .repeat = 1, ); err = bpf_prog_test_load("tailcall_bpf2bpf4.bpf.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd); if (CHECK_FAIL(err)) return; prog = bpf_object__find_program_by_name(obj, "entry"); if (CHECK_FAIL(!prog)) goto out; main_fd = bpf_program__fd(prog); if (CHECK_FAIL(main_fd < 0)) goto out; prog_array = bpf_object__find_map_by_name(obj, "jmp_table"); if (CHECK_FAIL(!prog_array)) goto out; map_fd = bpf_map__fd(prog_array); if (CHECK_FAIL(map_fd < 0)) goto out; for (i = 0; i < bpf_map__max_entries(prog_array); i++) { snprintf(prog_name, sizeof(prog_name), "classifier_%d", i); prog = bpf_object__find_program_by_name(obj, prog_name); if (CHECK_FAIL(!prog)) goto out; prog_fd = bpf_program__fd(prog); if (CHECK_FAIL(prog_fd < 0)) goto out; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (CHECK_FAIL(err)) goto out; } data_map = bpf_object__find_map_by_name(obj, "tailcall.bss"); if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map))) return; data_fd = bpf_map__fd(data_map); if (CHECK_FAIL(map_fd < 0)) return; i = 0; val.noise = noise; val.count = 0; err = bpf_map_update_elem(data_fd, &i, &val, BPF_ANY); if (CHECK_FAIL(err)) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, sizeof(pkt_v4) * 3, "tailcall retval"); i = 0; err = bpf_map_lookup_elem(data_fd, &i, &val); ASSERT_OK(err, "tailcall count"); ASSERT_EQ(val.count, 31, "tailcall count"); out: bpf_object__close(obj); } #include "tailcall_bpf2bpf6.skel.h" /* Tail call counting works even when there is data on stack which is * not aligned to 8 bytes. */ static void test_tailcall_bpf2bpf_6(void) { struct tailcall_bpf2bpf6 *obj; int err, map_fd, prog_fd, main_fd, data_fd, i, val; LIBBPF_OPTS(bpf_test_run_opts, topts, .data_in = &pkt_v4, .data_size_in = sizeof(pkt_v4), .repeat = 1, ); obj = tailcall_bpf2bpf6__open_and_load(); if (!ASSERT_OK_PTR(obj, "open and load")) return; main_fd = bpf_program__fd(obj->progs.entry); if (!ASSERT_GE(main_fd, 0, "entry prog fd")) goto out; map_fd = bpf_map__fd(obj->maps.jmp_table); if (!ASSERT_GE(map_fd, 0, "jmp_table map fd")) goto out; prog_fd = bpf_program__fd(obj->progs.classifier_0); if (!ASSERT_GE(prog_fd, 0, "classifier_0 prog fd")) goto out; i = 0; err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY); if (!ASSERT_OK(err, "jmp_table map update")) goto out; err = bpf_prog_test_run_opts(main_fd, &topts); ASSERT_OK(err, "entry prog test run"); ASSERT_EQ(topts.retval, 0, "tailcall retval"); data_fd = bpf_map__fd(obj->maps.bss); if (!ASSERT_GE(map_fd, 0, "bss map fd")) goto out; i = 0; err = bpf_map_lookup_elem(data_fd, &i, &val); ASSERT_OK(err, "bss map lookup"); ASSERT_EQ(val, 1, "done flag is set"); out: tailcall_bpf2bpf6__destroy(obj); } void test_tailcalls(void) { if (test__start_subtest("tailcall_1")) test_tailcall_1(); if (test__start_subtest("tailcall_2")) test_tailcall_2(); if (test__start_subtest("tailcall_3")) test_tailcall_3(); if (test__start_subtest("tailcall_4")) test_tailcall_4(); if (test__start_subtest("tailcall_5")) test_tailcall_5(); if (test__start_subtest("tailcall_6")) test_tailcall_6(); if (test__start_subtest("tailcall_bpf2bpf_1")) test_tailcall_bpf2bpf_1(); if (test__start_subtest("tailcall_bpf2bpf_2")) test_tailcall_bpf2bpf_2(); if (test__start_subtest("tailcall_bpf2bpf_3")) test_tailcall_bpf2bpf_3(); if (test__start_subtest("tailcall_bpf2bpf_4")) test_tailcall_bpf2bpf_4(false); if (test__start_subtest("tailcall_bpf2bpf_5")) test_tailcall_bpf2bpf_4(true); if (test__start_subtest("tailcall_bpf2bpf_6")) test_tailcall_bpf2bpf_6(); }