Add 4 test cases to confirm the tailcall infinite loop bug has been fixed. Like tailcall_bpf2bpf cases, do fentry/fexit on the bpf2bpf, and then check the final count result. tools/testing/selftests/bpf/test_progs -t tailcalls 226/13 tailcalls/tailcall_bpf2bpf_fentry:OK 226/14 tailcalls/tailcall_bpf2bpf_fexit:OK 226/15 tailcalls/tailcall_bpf2bpf_fentry_fexit:OK 226/16 tailcalls/tailcall_bpf2bpf_fentry_entry:OK 226 tailcalls:OK Summary: 1/16 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Leon Hwang <hffilwlqm@xxxxxxxxx> --- .../selftests/bpf/prog_tests/tailcalls.c | 237 +++++++++++++++++- .../bpf/progs/tailcall_bpf2bpf_fentry.c | 18 ++ .../bpf/progs/tailcall_bpf2bpf_fexit.c | 18 ++ 3 files changed, 269 insertions(+), 4 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fentry.c create mode 100644 tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fexit.c diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c index 09c189761926c..fc6b2954e8f50 100644 --- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c +++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c @@ -218,12 +218,14 @@ static void test_tailcall_2(void) bpf_object__close(obj); } -static void test_tailcall_count(const char *which) +static void test_tailcall_count(const char *which, bool test_fentry, + bool test_fexit) { + struct bpf_object *obj = NULL, *fentry_obj = NULL, *fexit_obj = NULL; + struct bpf_link *fentry_link = NULL, *fexit_link = NULL; 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, @@ -265,6 +267,54 @@ static void test_tailcall_count(const char *which) if (CHECK_FAIL(err)) 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(main_fd, &topts); ASSERT_OK(err, "tailcall"); ASSERT_EQ(topts.retval, 1, "tailcall retval"); @@ -282,6 +332,40 @@ static void test_tailcall_count(const char *which) ASSERT_OK(err, "tailcall count"); ASSERT_EQ(val, 33, "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; + + data_fd = bpf_map__fd(data_map); + if (!ASSERT_FALSE(data_fd < 0, + "find tailcall_bpf2bpf_fentry.bss map fd")) + goto out; + + i = 0; + err = bpf_map_lookup_elem(data_fd, &i, &val); + ASSERT_OK(err, "fentry count"); + ASSERT_EQ(val, 33, "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; + + data_fd = bpf_map__fd(data_map); + if (!ASSERT_FALSE(data_fd < 0, + "find tailcall_bpf2bpf_fexit.bss map fd")) + goto out; + + i = 0; + err = bpf_map_lookup_elem(data_fd, &i, &val); + ASSERT_OK(err, "fexit count"); + ASSERT_EQ(val, 33, "fexit count"); + } + i = 0; err = bpf_map_delete_elem(map_fd, &i); if (CHECK_FAIL(err)) @@ -291,6 +375,10 @@ static void test_tailcall_count(const char *which) ASSERT_OK(err, "tailcall"); ASSERT_OK(topts.retval, "tailcall retval"); 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); } @@ -299,7 +387,7 @@ static void test_tailcall_count(const char *which) */ static void test_tailcall_3(void) { - test_tailcall_count("tailcall3.bpf.o"); + test_tailcall_count("tailcall3.bpf.o", false, false); } /* test_tailcall_6 checks that the count value of the tail call limit @@ -307,7 +395,7 @@ static void test_tailcall_3(void) */ static void test_tailcall_6(void) { - test_tailcall_count("tailcall6.bpf.o"); + test_tailcall_count("tailcall6.bpf.o", false, false); } /* test_tailcall_4 checks that the kernel properly selects indirect jump @@ -884,6 +972,139 @@ static void test_tailcall_bpf2bpf_6(void) tailcall_bpf2bpf6__destroy(obj); } +/* test_tailcall_bpf2bpf_fentry checks that the count value of the tail call + * limit enforcement matches with expectations when tailcall is preceded with + * bpf2bpf call, and the bpf2bpf call is traced by fentry. + */ +static void test_tailcall_bpf2bpf_fentry(void) +{ + test_tailcall_count("tailcall_bpf2bpf2.bpf.o", true, false); +} + +/* test_tailcall_bpf2bpf_fexit checks that the count value of the tail call + * limit enforcement matches with expectations when tailcall is preceded with + * bpf2bpf call, and the bpf2bpf call is traced by fexit. + */ +static void test_tailcall_bpf2bpf_fexit(void) +{ + test_tailcall_count("tailcall_bpf2bpf2.bpf.o", false, true); +} + +/* test_tailcall_bpf2bpf_fentry_fexit checks that the count value of the tail + * call limit enforcement matches with expectations when tailcall is preceded + * with bpf2bpf call, and the bpf2bpf call is traced by both fentry and fexit. + */ +static void test_tailcall_bpf2bpf_fentry_fexit(void) +{ + test_tailcall_count("tailcall_bpf2bpf2.bpf.o", true, true); +} + +/* test_tailcall_bpf2bpf_fentry_entry checks that the count value of the tail + * call limit enforcement matches with expectations when tailcall is preceded + * with bpf2bpf call, and the bpf2bpf caller is traced by fentry. + */ +static void test_tailcall_bpf2bpf_fentry_entry(void) +{ + struct bpf_object *tgt_obj = NULL, *fentry_obj = NULL; + int err, map_fd, prog_fd, data_fd, i, val; + struct bpf_map *prog_array, *data_map; + struct bpf_link *fentry_link = NULL; + struct bpf_program *prog; + 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, + &tgt_obj, &prog_fd); + if (!ASSERT_OK(err, "load tgt_obj")) + return; + + prog_array = bpf_object__find_map_by_name(tgt_obj, "jmp_table"); + if (!ASSERT_OK_PTR(prog_array, "find jmp_table map")) + goto out; + + map_fd = bpf_map__fd(prog_array); + if (!ASSERT_FALSE(map_fd < 0, "find jmp_table map fd")) + goto out; + + prog = bpf_object__find_program_by_name(tgt_obj, "classifier_0"); + if (!ASSERT_OK_PTR(prog, "find classifier_0 prog")) + goto out; + + prog_fd = bpf_program__fd(prog); + if (!ASSERT_FALSE(prog_fd < 0, "find classifier_0 prog 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; + + 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, "classifier_0"); + if (!ASSERT_OK(err, "set_attach_target classifier_0")) + 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; + + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "tailcall"); + ASSERT_EQ(topts.retval, 1, "tailcall retval"); + + data_map = bpf_object__find_map_by_name(tgt_obj, "tailcall.bss"); + if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map), + "find tailcall.bss map")) + goto out; + + data_fd = bpf_map__fd(data_map); + if (!ASSERT_FALSE(data_fd < 0, "find tailcall.bss map fd")) + goto out; + + i = 0; + err = bpf_map_lookup_elem(data_fd, &i, &val); + ASSERT_OK(err, "tailcall count"); + ASSERT_EQ(val, 34, "tailcall count"); + + 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; + + data_fd = bpf_map__fd(data_map); + if (!ASSERT_FALSE(data_fd < 0, + "find tailcall_bpf2bpf_fentry.bss map fd")) + goto out; + + i = 0; + err = bpf_map_lookup_elem(data_fd, &i, &val); + ASSERT_OK(err, "fentry count"); + ASSERT_EQ(val, 1, "fentry count"); + +out: + bpf_link__destroy(fentry_link); + bpf_object__close(fentry_obj); + bpf_object__close(tgt_obj); +} + void test_tailcalls(void) { if (test__start_subtest("tailcall_1")) @@ -910,4 +1131,12 @@ void test_tailcalls(void) test_tailcall_bpf2bpf_4(true); if (test__start_subtest("tailcall_bpf2bpf_6")) test_tailcall_bpf2bpf_6(); + if (test__start_subtest("tailcall_bpf2bpf_fentry")) + test_tailcall_bpf2bpf_fentry(); + if (test__start_subtest("tailcall_bpf2bpf_fexit")) + test_tailcall_bpf2bpf_fexit(); + if (test__start_subtest("tailcall_bpf2bpf_fentry_fexit")) + test_tailcall_bpf2bpf_fentry_fexit(); + if (test__start_subtest("tailcall_bpf2bpf_fentry_entry")) + test_tailcall_bpf2bpf_fentry_entry(); } diff --git a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fentry.c b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fentry.c new file mode 100644 index 0000000000000..8436c6729167c --- /dev/null +++ b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fentry.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright Leon Hwang */ + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +int count = 0; + +SEC("fentry/subprog_tail") +int BPF_PROG(fentry, struct sk_buff *skb) +{ + count++; + + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fexit.c b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fexit.c new file mode 100644 index 0000000000000..fe16412c6e6e9 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_fexit.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright Leon Hwang */ + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +int count = 0; + +SEC("fexit/subprog_tail") +int BPF_PROG(fexit, struct sk_buff *skb) +{ + count++; + + return 0; +} + +char _license[] SEC("license") = "GPL"; -- 2.41.0