selftests/bpf: Add testcases for tailcall hierarchy fixing
Add some test cases to confirm the tailcall hierarchy issue has been fixed. On x64, the selftests result is: cd tools/testing/selftests/bpf && ./test_progs -t tailcalls 327/18 tailcalls/tailcall_bpf2bpf_hierarchy_1:OK 327/19 tailcalls/tailcall_bpf2bpf_hierarchy_fentry:OK 327/20 tailcalls/tailcall_bpf2bpf_hierarchy_fexit:OK 327/21 tailcalls/tailcall_bpf2bpf_hierarchy_fentry_fexit:OK 327/22 tailcalls/tailcall_bpf2bpf_hierarchy_fentry_entry:OK 327/23 tailcalls/tailcall_bpf2bpf_hierarchy_2:OK 327/24 tailcalls/tailcall_bpf2bpf_hierarchy_3:OK 327 tailcalls:OK Summary: 1/24 PASSED, 0 SKIPPED, 0 FAILED On arm64, the selftests result is: cd tools/testing/selftests/bpf && ./test_progs -t tailcalls 327/18 tailcalls/tailcall_bpf2bpf_hierarchy_1:OK 327/19 tailcalls/tailcall_bpf2bpf_hierarchy_fentry:OK 327/20 tailcalls/tailcall_bpf2bpf_hierarchy_fexit:OK 327/21 tailcalls/tailcall_bpf2bpf_hierarchy_fentry_fexit:OK 327/22 tailcalls/tailcall_bpf2bpf_hierarchy_fentry_entry:OK 327/23 tailcalls/tailcall_bpf2bpf_hierarchy_2:OK 327/24 tailcalls/tailcall_bpf2bpf_hierarchy_3:OK 327 tailcalls:OK Summary: 1/24 PASSED, 0 SKIPPED, 0 FAILED Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Leon Hwang <hffilwlqm@gmail.com> Link: https://lore.kernel.org/r/20240714123902.32305-4-hffilwlqm@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
This commit is contained in:
Leon Hwang
committed by
Andrii Nakryiko
Andrii Nakryiko
parent
66ff4d61dc
commit
b83b936f3e
@@ -3,6 +3,8 @@
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#include <test_progs.h>
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#include <network_helpers.h>
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#include "tailcall_poke.skel.h"
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#include "tailcall_bpf2bpf_hierarchy2.skel.h"
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#include "tailcall_bpf2bpf_hierarchy3.skel.h"
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/* test_tailcall_1 checks basic functionality by patching multiple locations
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@@ -1187,6 +1189,312 @@ out:
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tailcall_poke__destroy(call);
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}
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static void test_tailcall_hierarchy_count(const char *which, bool test_fentry,
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bool test_fexit,
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bool test_fentry_entry)
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{
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int err, map_fd, prog_fd, main_data_fd, fentry_data_fd, fexit_data_fd, i, val;
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struct bpf_object *obj = NULL, *fentry_obj = NULL, *fexit_obj = NULL;
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struct bpf_link *fentry_link = NULL, *fexit_link = NULL;
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struct bpf_program *prog, *fentry_prog;
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struct bpf_map *prog_array, *data_map;
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int fentry_prog_fd;
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char buff[128] = {};
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LIBBPF_OPTS(bpf_test_run_opts, topts,
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.data_in = buff,
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.data_size_in = sizeof(buff),
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.repeat = 1,
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);
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err = bpf_prog_test_load(which, BPF_PROG_TYPE_SCHED_CLS, &obj,
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&prog_fd);
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if (!ASSERT_OK(err, "load obj"))
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return;
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prog = bpf_object__find_program_by_name(obj, "entry");
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if (!ASSERT_OK_PTR(prog, "find entry prog"))
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goto out;
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prog_fd = bpf_program__fd(prog);
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if (!ASSERT_GE(prog_fd, 0, "prog_fd"))
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goto out;
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if (test_fentry_entry) {
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fentry_obj = bpf_object__open_file("tailcall_bpf2bpf_hierarchy_fentry.bpf.o",
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NULL);
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if (!ASSERT_OK_PTR(fentry_obj, "open fentry_obj file"))
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goto out;
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fentry_prog = bpf_object__find_program_by_name(fentry_obj,
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"fentry");
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if (!ASSERT_OK_PTR(prog, "find fentry prog"))
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goto out;
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err = bpf_program__set_attach_target(fentry_prog, prog_fd,
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"entry");
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if (!ASSERT_OK(err, "set_attach_target entry"))
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goto out;
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err = bpf_object__load(fentry_obj);
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if (!ASSERT_OK(err, "load fentry_obj"))
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goto out;
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fentry_link = bpf_program__attach_trace(fentry_prog);
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if (!ASSERT_OK_PTR(fentry_link, "attach_trace"))
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goto out;
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fentry_prog_fd = bpf_program__fd(fentry_prog);
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if (!ASSERT_GE(fentry_prog_fd, 0, "fentry_prog_fd"))
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goto out;
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prog_array = bpf_object__find_map_by_name(fentry_obj, "jmp_table");
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if (!ASSERT_OK_PTR(prog_array, "find jmp_table"))
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goto out;
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map_fd = bpf_map__fd(prog_array);
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if (!ASSERT_GE(map_fd, 0, "map_fd"))
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goto out;
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i = 0;
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err = bpf_map_update_elem(map_fd, &i, &fentry_prog_fd, BPF_ANY);
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if (!ASSERT_OK(err, "update jmp_table"))
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goto out;
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data_map = bpf_object__find_map_by_name(fentry_obj, ".bss");
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if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
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"find data_map"))
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goto out;
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} else {
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prog_array = bpf_object__find_map_by_name(obj, "jmp_table");
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if (!ASSERT_OK_PTR(prog_array, "find jmp_table"))
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goto out;
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map_fd = bpf_map__fd(prog_array);
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if (!ASSERT_GE(map_fd, 0, "map_fd"))
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goto out;
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i = 0;
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err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
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if (!ASSERT_OK(err, "update jmp_table"))
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goto out;
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data_map = bpf_object__find_map_by_name(obj, ".bss");
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if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
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"find data_map"))
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goto out;
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}
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if (test_fentry) {
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fentry_obj = bpf_object__open_file("tailcall_bpf2bpf_fentry.bpf.o",
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NULL);
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if (!ASSERT_OK_PTR(fentry_obj, "open fentry_obj file"))
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goto out;
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prog = bpf_object__find_program_by_name(fentry_obj, "fentry");
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if (!ASSERT_OK_PTR(prog, "find fentry prog"))
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goto out;
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err = bpf_program__set_attach_target(prog, prog_fd,
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"subprog_tail");
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if (!ASSERT_OK(err, "set_attach_target subprog_tail"))
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goto out;
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err = bpf_object__load(fentry_obj);
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if (!ASSERT_OK(err, "load fentry_obj"))
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goto out;
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fentry_link = bpf_program__attach_trace(prog);
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if (!ASSERT_OK_PTR(fentry_link, "attach_trace"))
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goto out;
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}
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if (test_fexit) {
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fexit_obj = bpf_object__open_file("tailcall_bpf2bpf_fexit.bpf.o",
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NULL);
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if (!ASSERT_OK_PTR(fexit_obj, "open fexit_obj file"))
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goto out;
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prog = bpf_object__find_program_by_name(fexit_obj, "fexit");
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if (!ASSERT_OK_PTR(prog, "find fexit prog"))
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goto out;
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err = bpf_program__set_attach_target(prog, prog_fd,
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"subprog_tail");
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if (!ASSERT_OK(err, "set_attach_target subprog_tail"))
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goto out;
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err = bpf_object__load(fexit_obj);
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if (!ASSERT_OK(err, "load fexit_obj"))
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goto out;
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fexit_link = bpf_program__attach_trace(prog);
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if (!ASSERT_OK_PTR(fexit_link, "attach_trace"))
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goto out;
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}
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err = bpf_prog_test_run_opts(prog_fd, &topts);
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ASSERT_OK(err, "tailcall");
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ASSERT_EQ(topts.retval, 1, "tailcall retval");
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main_data_fd = bpf_map__fd(data_map);
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if (!ASSERT_GE(main_data_fd, 0, "main_data_fd"))
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goto out;
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i = 0;
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err = bpf_map_lookup_elem(main_data_fd, &i, &val);
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ASSERT_OK(err, "tailcall count");
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ASSERT_EQ(val, 34, "tailcall count");
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if (test_fentry) {
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data_map = bpf_object__find_map_by_name(fentry_obj, ".bss");
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if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
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"find tailcall_bpf2bpf_fentry.bss map"))
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goto out;
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fentry_data_fd = bpf_map__fd(data_map);
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if (!ASSERT_GE(fentry_data_fd, 0,
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"find tailcall_bpf2bpf_fentry.bss map fd"))
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goto out;
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i = 0;
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err = bpf_map_lookup_elem(fentry_data_fd, &i, &val);
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ASSERT_OK(err, "fentry count");
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ASSERT_EQ(val, 68, "fentry count");
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}
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if (test_fexit) {
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data_map = bpf_object__find_map_by_name(fexit_obj, ".bss");
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if (!ASSERT_FALSE(!data_map || !bpf_map__is_internal(data_map),
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"find tailcall_bpf2bpf_fexit.bss map"))
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goto out;
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fexit_data_fd = bpf_map__fd(data_map);
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if (!ASSERT_GE(fexit_data_fd, 0,
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"find tailcall_bpf2bpf_fexit.bss map fd"))
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goto out;
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i = 0;
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err = bpf_map_lookup_elem(fexit_data_fd, &i, &val);
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ASSERT_OK(err, "fexit count");
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ASSERT_EQ(val, 68, "fexit count");
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}
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i = 0;
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err = bpf_map_delete_elem(map_fd, &i);
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if (!ASSERT_OK(err, "delete_elem from jmp_table"))
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goto out;
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err = bpf_prog_test_run_opts(prog_fd, &topts);
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ASSERT_OK(err, "tailcall");
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ASSERT_EQ(topts.retval, 1, "tailcall retval");
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i = 0;
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err = bpf_map_lookup_elem(main_data_fd, &i, &val);
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ASSERT_OK(err, "tailcall count");
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ASSERT_EQ(val, 35, "tailcall count");
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if (test_fentry) {
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i = 0;
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err = bpf_map_lookup_elem(fentry_data_fd, &i, &val);
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ASSERT_OK(err, "fentry count");
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ASSERT_EQ(val, 70, "fentry count");
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}
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if (test_fexit) {
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i = 0;
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err = bpf_map_lookup_elem(fexit_data_fd, &i, &val);
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ASSERT_OK(err, "fexit count");
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ASSERT_EQ(val, 70, "fexit count");
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}
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out:
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bpf_link__destroy(fentry_link);
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bpf_link__destroy(fexit_link);
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bpf_object__close(fentry_obj);
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bpf_object__close(fexit_obj);
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bpf_object__close(obj);
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}
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/* test_tailcall_bpf2bpf_hierarchy_1 checks that the count value of the tail
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* call limit enforcement matches with expectations when tailcalls are preceded
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* with two bpf2bpf calls.
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*
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* subprog --tailcall-> entry
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* entry <
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* subprog --tailcall-> entry
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*/
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static void test_tailcall_bpf2bpf_hierarchy_1(void)
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{
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test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
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false, false, false);
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}
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/* test_tailcall_bpf2bpf_hierarchy_fentry checks that the count value of the
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* tail call limit enforcement matches with expectations when tailcalls are
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* preceded with two bpf2bpf calls, and the two subprogs are traced by fentry.
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*/
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static void test_tailcall_bpf2bpf_hierarchy_fentry(void)
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{
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test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
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true, false, false);
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}
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/* test_tailcall_bpf2bpf_hierarchy_fexit checks that the count value of the tail
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* call limit enforcement matches with expectations when tailcalls are preceded
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* with two bpf2bpf calls, and the two subprogs are traced by fexit.
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*/
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static void test_tailcall_bpf2bpf_hierarchy_fexit(void)
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{
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test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
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false, true, false);
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}
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/* test_tailcall_bpf2bpf_hierarchy_fentry_fexit checks that the count value of
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* the tail call limit enforcement matches with expectations when tailcalls are
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* preceded with two bpf2bpf calls, and the two subprogs are traced by both
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* fentry and fexit.
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*/
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static void test_tailcall_bpf2bpf_hierarchy_fentry_fexit(void)
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{
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test_tailcall_hierarchy_count("tailcall_bpf2bpf_hierarchy1.bpf.o",
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true, true, false);
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}
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/* test_tailcall_bpf2bpf_hierarchy_fentry_entry checks that the count value of
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* the tail call limit enforcement matches with expectations when tailcalls are
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* preceded with two bpf2bpf calls in fentry.
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*/
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static void test_tailcall_bpf2bpf_hierarchy_fentry_entry(void)
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{
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test_tailcall_hierarchy_count("tc_dummy.bpf.o", false, false, true);
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}
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/* test_tailcall_bpf2bpf_hierarchy_2 checks that the count value of the tail
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* call limit enforcement matches with expectations:
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*
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* subprog_tail0 --tailcall-> classifier_0 -> subprog_tail0
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* entry <
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* subprog_tail1 --tailcall-> classifier_1 -> subprog_tail1
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*/
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static void test_tailcall_bpf2bpf_hierarchy_2(void)
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{
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RUN_TESTS(tailcall_bpf2bpf_hierarchy2);
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}
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/* test_tailcall_bpf2bpf_hierarchy_3 checks that the count value of the tail
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* call limit enforcement matches with expectations:
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*
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* subprog with jmp_table0 to classifier_0
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* entry --tailcall-> classifier_0 <
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* subprog with jmp_table1 to classifier_0
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*/
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static void test_tailcall_bpf2bpf_hierarchy_3(void)
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{
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RUN_TESTS(tailcall_bpf2bpf_hierarchy3);
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}
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void test_tailcalls(void)
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{
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if (test__start_subtest("tailcall_1"))
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@@ -1223,4 +1531,16 @@ void test_tailcalls(void)
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test_tailcall_bpf2bpf_fentry_entry();
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if (test__start_subtest("tailcall_poke"))
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test_tailcall_poke();
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if (test__start_subtest("tailcall_bpf2bpf_hierarchy_1"))
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test_tailcall_bpf2bpf_hierarchy_1();
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if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fentry"))
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test_tailcall_bpf2bpf_hierarchy_fentry();
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if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fexit"))
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test_tailcall_bpf2bpf_hierarchy_fexit();
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if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fentry_fexit"))
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test_tailcall_bpf2bpf_hierarchy_fentry_fexit();
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if (test__start_subtest("tailcall_bpf2bpf_hierarchy_fentry_entry"))
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test_tailcall_bpf2bpf_hierarchy_fentry_entry();
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test_tailcall_bpf2bpf_hierarchy_2();
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test_tailcall_bpf2bpf_hierarchy_3();
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}
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@@ -0,0 +1,34 @@
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// SPDX-License-Identifier: GPL-2.0
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include "bpf_legacy.h"
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struct {
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__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
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__uint(max_entries, 1);
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__uint(key_size, sizeof(__u32));
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__uint(value_size, sizeof(__u32));
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} jmp_table SEC(".maps");
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int count = 0;
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static __noinline
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int subprog_tail(struct __sk_buff *skb)
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{
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bpf_tail_call_static(skb, &jmp_table, 0);
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return 0;
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}
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SEC("tc")
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int entry(struct __sk_buff *skb)
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{
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int ret = 1;
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count++;
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subprog_tail(skb);
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subprog_tail(skb);
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return ret;
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}
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char __license[] SEC("license") = "GPL";
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@@ -0,0 +1,70 @@
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// SPDX-License-Identifier: GPL-2.0
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include "bpf_misc.h"
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int classifier_0(struct __sk_buff *skb);
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int classifier_1(struct __sk_buff *skb);
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struct {
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__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
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__uint(max_entries, 2);
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__uint(key_size, sizeof(__u32));
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__array(values, void (void));
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} jmp_table SEC(".maps") = {
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.values = {
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[0] = (void *) &classifier_0,
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[1] = (void *) &classifier_1,
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},
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};
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int count0 = 0;
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int count1 = 0;
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static __noinline
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int subprog_tail0(struct __sk_buff *skb)
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{
|
||||
bpf_tail_call_static(skb, &jmp_table, 0);
|
||||
return 0;
|
||||
}
|
||||
|
||||
__auxiliary
|
||||
SEC("tc")
|
||||
int classifier_0(struct __sk_buff *skb)
|
||||
{
|
||||
count0++;
|
||||
subprog_tail0(skb);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static __noinline
|
||||
int subprog_tail1(struct __sk_buff *skb)
|
||||
{
|
||||
bpf_tail_call_static(skb, &jmp_table, 1);
|
||||
return 0;
|
||||
}
|
||||
|
||||
__auxiliary
|
||||
SEC("tc")
|
||||
int classifier_1(struct __sk_buff *skb)
|
||||
{
|
||||
count1++;
|
||||
subprog_tail1(skb);
|
||||
return 0;
|
||||
}
|
||||
|
||||
__success
|
||||
__retval(33)
|
||||
SEC("tc")
|
||||
int tailcall_bpf2bpf_hierarchy_2(struct __sk_buff *skb)
|
||||
{
|
||||
volatile int ret = 0;
|
||||
|
||||
subprog_tail0(skb);
|
||||
subprog_tail1(skb);
|
||||
|
||||
asm volatile (""::"r+"(ret));
|
||||
return (count1 << 16) | count0;
|
||||
}
|
||||
|
||||
char __license[] SEC("license") = "GPL";
|
||||
@@ -0,0 +1,62 @@
|
||||
// SPDX-License-Identifier: GPL-2.0
|
||||
#include <linux/bpf.h>
|
||||
#include <bpf/bpf_helpers.h>
|
||||
#include "bpf_misc.h"
|
||||
|
||||
int classifier_0(struct __sk_buff *skb);
|
||||
|
||||
struct {
|
||||
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
|
||||
__uint(max_entries, 1);
|
||||
__uint(key_size, sizeof(__u32));
|
||||
__array(values, void (void));
|
||||
} jmp_table0 SEC(".maps") = {
|
||||
.values = {
|
||||
[0] = (void *) &classifier_0,
|
||||
},
|
||||
};
|
||||
|
||||
struct {
|
||||
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
|
||||
__uint(max_entries, 1);
|
||||
__uint(key_size, sizeof(__u32));
|
||||
__array(values, void (void));
|
||||
} jmp_table1 SEC(".maps") = {
|
||||
.values = {
|
||||
[0] = (void *) &classifier_0,
|
||||
},
|
||||
};
|
||||
|
||||
int count = 0;
|
||||
|
||||
static __noinline
|
||||
int subprog_tail(struct __sk_buff *skb, void *jmp_table)
|
||||
{
|
||||
bpf_tail_call_static(skb, jmp_table, 0);
|
||||
return 0;
|
||||
}
|
||||
|
||||
__auxiliary
|
||||
SEC("tc")
|
||||
int classifier_0(struct __sk_buff *skb)
|
||||
{
|
||||
count++;
|
||||
subprog_tail(skb, &jmp_table0);
|
||||
subprog_tail(skb, &jmp_table1);
|
||||
return count;
|
||||
}
|
||||
|
||||
__success
|
||||
__retval(33)
|
||||
SEC("tc")
|
||||
int tailcall_bpf2bpf_hierarchy_3(struct __sk_buff *skb)
|
||||
{
|
||||
volatile int ret = 0;
|
||||
|
||||
bpf_tail_call_static(skb, &jmp_table0, 0);
|
||||
|
||||
asm volatile (""::"r+"(ret));
|
||||
return ret;
|
||||
}
|
||||
|
||||
char __license[] SEC("license") = "GPL";
|
||||
@@ -0,0 +1,35 @@
|
||||
// SPDX-License-Identifier: GPL-2.0
|
||||
/* Copyright Leon Hwang */
|
||||
|
||||
#include "vmlinux.h"
|
||||
#include <bpf/bpf_helpers.h>
|
||||
#include <bpf/bpf_tracing.h>
|
||||
|
||||
struct {
|
||||
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
|
||||
__uint(max_entries, 1);
|
||||
__uint(key_size, sizeof(__u32));
|
||||
__uint(value_size, sizeof(__u32));
|
||||
} jmp_table SEC(".maps");
|
||||
|
||||
int count = 0;
|
||||
|
||||
static __noinline
|
||||
int subprog_tail(void *ctx)
|
||||
{
|
||||
bpf_tail_call_static(ctx, &jmp_table, 0);
|
||||
return 0;
|
||||
}
|
||||
|
||||
SEC("fentry/dummy")
|
||||
int BPF_PROG(fentry, struct sk_buff *skb)
|
||||
{
|
||||
count++;
|
||||
subprog_tail(ctx);
|
||||
subprog_tail(ctx);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
char _license[] SEC("license") = "GPL";
|
||||
@@ -0,0 +1,12 @@
|
||||
// SPDX-License-Identifier: GPL-2.0
|
||||
#include <linux/bpf.h>
|
||||
#include <bpf/bpf_helpers.h>
|
||||
#include "bpf_legacy.h"
|
||||
|
||||
SEC("tc")
|
||||
int entry(struct __sk_buff *skb)
|
||||
{
|
||||
return 1;
|
||||
}
|
||||
|
||||
char __license[] SEC("license") = "GPL";
|
||||
Reference in New Issue
Block a user