From 5e0b0a4c52d30bb09659446f40b77a692361600d Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Thu, 16 Jun 2022 18:20:37 +0200 Subject: selftests/bpf: Test tail call counting with bpf2bpf and data on stack Cover the case when tail call count needs to be passed from BPF function to BPF function, and the caller has data on stack. Specifically when the size of data allocated on BPF stack is not a multiple on 8. Signed-off-by: Jakub Sitnicki Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20220616162037.535469-3-jakub@cloudflare.com --- tools/testing/selftests/bpf/prog_tests/tailcalls.c | 55 ++++++++++++++++++++++ 1 file changed, 55 insertions(+) (limited to 'tools/testing/selftests/bpf/prog_tests') diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c index c4da87ec3ba4..19c70880cfb3 100644 --- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c +++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c @@ -831,6 +831,59 @@ 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")) @@ -855,4 +908,6 @@ void test_tailcalls(void) 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(); } -- cgit v1.2.3 From ad8848535e97f4a5374fc68f7a5d16e2565940cc Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 15 Jun 2022 13:21:15 +0200 Subject: selftests/bpf: Shuffle cookies symbols in kprobe multi test There's a kernel bug that causes cookies to be misplaced and the reason we did not catch this with this test is that we provide bpf_fentry_test* functions already sorted by name. Shuffling function bpf_fentry_test2 deeper in the list and keeping the current cookie values as before will trigger the bug. The kernel fix is coming in following changes. Acked-by: Song Liu Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20220615112118.497303-2-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- .../testing/selftests/bpf/prog_tests/bpf_cookie.c | 78 +++++++++++----------- tools/testing/selftests/bpf/progs/kprobe_multi.c | 24 +++---- 2 files changed, 51 insertions(+), 51 deletions(-) (limited to 'tools/testing/selftests/bpf/prog_tests') diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c index 83ef55e3caa4..2974b44f80fa 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c @@ -121,24 +121,24 @@ static void kprobe_multi_link_api_subtest(void) }) GET_ADDR("bpf_fentry_test1", addrs[0]); - GET_ADDR("bpf_fentry_test2", addrs[1]); - GET_ADDR("bpf_fentry_test3", addrs[2]); - GET_ADDR("bpf_fentry_test4", addrs[3]); - GET_ADDR("bpf_fentry_test5", addrs[4]); - GET_ADDR("bpf_fentry_test6", addrs[5]); - GET_ADDR("bpf_fentry_test7", addrs[6]); + GET_ADDR("bpf_fentry_test3", addrs[1]); + GET_ADDR("bpf_fentry_test4", addrs[2]); + GET_ADDR("bpf_fentry_test5", addrs[3]); + GET_ADDR("bpf_fentry_test6", addrs[4]); + GET_ADDR("bpf_fentry_test7", addrs[5]); + GET_ADDR("bpf_fentry_test2", addrs[6]); GET_ADDR("bpf_fentry_test8", addrs[7]); #undef GET_ADDR - cookies[0] = 1; - cookies[1] = 2; - cookies[2] = 3; - cookies[3] = 4; - cookies[4] = 5; - cookies[5] = 6; - cookies[6] = 7; - cookies[7] = 8; + cookies[0] = 1; /* bpf_fentry_test1 */ + cookies[1] = 2; /* bpf_fentry_test3 */ + cookies[2] = 3; /* bpf_fentry_test4 */ + cookies[3] = 4; /* bpf_fentry_test5 */ + cookies[4] = 5; /* bpf_fentry_test6 */ + cookies[5] = 6; /* bpf_fentry_test7 */ + cookies[6] = 7; /* bpf_fentry_test2 */ + cookies[7] = 8; /* bpf_fentry_test8 */ opts.kprobe_multi.addrs = (const unsigned long *) &addrs; opts.kprobe_multi.cnt = ARRAY_SIZE(addrs); @@ -149,14 +149,14 @@ static void kprobe_multi_link_api_subtest(void) if (!ASSERT_GE(link1_fd, 0, "link1_fd")) goto cleanup; - cookies[0] = 8; - cookies[1] = 7; - cookies[2] = 6; - cookies[3] = 5; - cookies[4] = 4; - cookies[5] = 3; - cookies[6] = 2; - cookies[7] = 1; + cookies[0] = 8; /* bpf_fentry_test1 */ + cookies[1] = 7; /* bpf_fentry_test3 */ + cookies[2] = 6; /* bpf_fentry_test4 */ + cookies[3] = 5; /* bpf_fentry_test5 */ + cookies[4] = 4; /* bpf_fentry_test6 */ + cookies[5] = 3; /* bpf_fentry_test7 */ + cookies[6] = 2; /* bpf_fentry_test2 */ + cookies[7] = 1; /* bpf_fentry_test8 */ opts.kprobe_multi.flags = BPF_F_KPROBE_MULTI_RETURN; prog_fd = bpf_program__fd(skel->progs.test_kretprobe); @@ -181,12 +181,12 @@ static void kprobe_multi_attach_api_subtest(void) struct kprobe_multi *skel = NULL; const char *syms[8] = { "bpf_fentry_test1", - "bpf_fentry_test2", "bpf_fentry_test3", "bpf_fentry_test4", "bpf_fentry_test5", "bpf_fentry_test6", "bpf_fentry_test7", + "bpf_fentry_test2", "bpf_fentry_test8", }; __u64 cookies[8]; @@ -198,14 +198,14 @@ static void kprobe_multi_attach_api_subtest(void) skel->bss->pid = getpid(); skel->bss->test_cookie = true; - cookies[0] = 1; - cookies[1] = 2; - cookies[2] = 3; - cookies[3] = 4; - cookies[4] = 5; - cookies[5] = 6; - cookies[6] = 7; - cookies[7] = 8; + cookies[0] = 1; /* bpf_fentry_test1 */ + cookies[1] = 2; /* bpf_fentry_test3 */ + cookies[2] = 3; /* bpf_fentry_test4 */ + cookies[3] = 4; /* bpf_fentry_test5 */ + cookies[4] = 5; /* bpf_fentry_test6 */ + cookies[5] = 6; /* bpf_fentry_test7 */ + cookies[6] = 7; /* bpf_fentry_test2 */ + cookies[7] = 8; /* bpf_fentry_test8 */ opts.syms = syms; opts.cnt = ARRAY_SIZE(syms); @@ -216,14 +216,14 @@ static void kprobe_multi_attach_api_subtest(void) if (!ASSERT_OK_PTR(link1, "bpf_program__attach_kprobe_multi_opts")) goto cleanup; - cookies[0] = 8; - cookies[1] = 7; - cookies[2] = 6; - cookies[3] = 5; - cookies[4] = 4; - cookies[5] = 3; - cookies[6] = 2; - cookies[7] = 1; + cookies[0] = 8; /* bpf_fentry_test1 */ + cookies[1] = 7; /* bpf_fentry_test3 */ + cookies[2] = 6; /* bpf_fentry_test4 */ + cookies[3] = 5; /* bpf_fentry_test5 */ + cookies[4] = 4; /* bpf_fentry_test6 */ + cookies[5] = 3; /* bpf_fentry_test7 */ + cookies[6] = 2; /* bpf_fentry_test2 */ + cookies[7] = 1; /* bpf_fentry_test8 */ opts.retprobe = true; diff --git a/tools/testing/selftests/bpf/progs/kprobe_multi.c b/tools/testing/selftests/bpf/progs/kprobe_multi.c index 93510f4f0f3a..08f95a8155d1 100644 --- a/tools/testing/selftests/bpf/progs/kprobe_multi.c +++ b/tools/testing/selftests/bpf/progs/kprobe_multi.c @@ -54,21 +54,21 @@ static void kprobe_multi_check(void *ctx, bool is_return) if (is_return) { SET(kretprobe_test1_result, &bpf_fentry_test1, 8); - SET(kretprobe_test2_result, &bpf_fentry_test2, 7); - SET(kretprobe_test3_result, &bpf_fentry_test3, 6); - SET(kretprobe_test4_result, &bpf_fentry_test4, 5); - SET(kretprobe_test5_result, &bpf_fentry_test5, 4); - SET(kretprobe_test6_result, &bpf_fentry_test6, 3); - SET(kretprobe_test7_result, &bpf_fentry_test7, 2); + SET(kretprobe_test2_result, &bpf_fentry_test2, 2); + SET(kretprobe_test3_result, &bpf_fentry_test3, 7); + SET(kretprobe_test4_result, &bpf_fentry_test4, 6); + SET(kretprobe_test5_result, &bpf_fentry_test5, 5); + SET(kretprobe_test6_result, &bpf_fentry_test6, 4); + SET(kretprobe_test7_result, &bpf_fentry_test7, 3); SET(kretprobe_test8_result, &bpf_fentry_test8, 1); } else { SET(kprobe_test1_result, &bpf_fentry_test1, 1); - SET(kprobe_test2_result, &bpf_fentry_test2, 2); - SET(kprobe_test3_result, &bpf_fentry_test3, 3); - SET(kprobe_test4_result, &bpf_fentry_test4, 4); - SET(kprobe_test5_result, &bpf_fentry_test5, 5); - SET(kprobe_test6_result, &bpf_fentry_test6, 6); - SET(kprobe_test7_result, &bpf_fentry_test7, 7); + SET(kprobe_test2_result, &bpf_fentry_test2, 7); + SET(kprobe_test3_result, &bpf_fentry_test3, 2); + SET(kprobe_test4_result, &bpf_fentry_test4, 3); + SET(kprobe_test5_result, &bpf_fentry_test5, 4); + SET(kprobe_test6_result, &bpf_fentry_test6, 5); + SET(kprobe_test7_result, &bpf_fentry_test7, 6); SET(kprobe_test8_result, &bpf_fentry_test8, 8); } -- cgit v1.2.3 From 730067022c0137691b27726377c2d088f7f8e33c Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 15 Jun 2022 13:21:18 +0200 Subject: selftest/bpf: Fix kprobe_multi bench test With [1] the available_filter_functions file contains records starting with __ftrace_invalid_address___ and marking disabled entries. We need to filter them out for the bench test to pass only resolvable symbols to kernel. [1] commit b39181f7c690 ("ftrace: Add FTRACE_MCOUNT_MAX_OFFSET to avoid adding weak function") Fixes: b39181f7c690 ("ftrace: Add FTRACE_MCOUNT_MAX_OFFSET to avoid adding weak function") Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20220615112118.497303-5-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools/testing/selftests/bpf/prog_tests') diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c index 586dc52d6fb9..5b93d5d0bd93 100644 --- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c +++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c @@ -364,6 +364,9 @@ static int get_syms(char ***symsp, size_t *cntp) continue; if (!strncmp(name, "rcu_", 4)) continue; + if (!strncmp(name, "__ftrace_invalid_address__", + sizeof("__ftrace_invalid_address__") - 1)) + continue; err = hashmap__add(map, name, NULL); if (err) { free(name); -- cgit v1.2.3