bpf: Add test ops for BPF_PROG_TYPE_TRACING

The current fexit and fentry tests rely on a different program to
exercise the functions they attach to. Instead of doing this, implement
the test operations for tracing which will also be used for
BPF_MODIFY_RETURN in a subsequent patch.

Also, clean up the fexit test to use the generated skeleton.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200304191853.1529-7-kpsingh@chromium.org

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index f748b31..40c5392 100644 (file)
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1156,6 +1156,9 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
                          union bpf_attr __user *uattr);
 int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
                          union bpf_attr __user *uattr);
+int bpf_prog_test_run_tracing(struct bpf_prog *prog,
+                             const union bpf_attr *kattr,
+                             union bpf_attr __user *uattr);
 int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
                                     const union bpf_attr *kattr,
                                     union bpf_attr __user *uattr);
@@ -1313,6 +1316,13 @@ static inline int bpf_prog_test_run_skb(struct bpf_prog *prog,
        return -ENOTSUPP;
 }
 
+static inline int bpf_prog_test_run_tracing(struct bpf_prog *prog,
+                                           const union bpf_attr *kattr,
+                                           union bpf_attr __user *uattr)
+{
+       return -ENOTSUPP;
+}
+
 static inline int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
                                                   const union bpf_attr *kattr,
                                                   union bpf_attr __user *uattr)

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 07764c7..363e0a2 100644 (file)
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1266,6 +1266,7 @@ const struct bpf_verifier_ops tracing_verifier_ops = {
 };
 
 const struct bpf_prog_ops tracing_prog_ops = {
+       .test_run = bpf_prog_test_run_tracing,
 };
 
 static bool raw_tp_writable_prog_is_valid_access(int off, int size,

diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 1cd7a1c..3600f09 100644 (file)
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -160,18 +160,37 @@ static void *bpf_test_init(const union bpf_attr *kattr, u32 size,
                kfree(data);
                return ERR_PTR(-EFAULT);
        }
-       if (bpf_fentry_test1(1) != 2 ||
-           bpf_fentry_test2(2, 3) != 5 ||
-           bpf_fentry_test3(4, 5, 6) != 15 ||
-           bpf_fentry_test4((void *)7, 8, 9, 10) != 34 ||
-           bpf_fentry_test5(11, (void *)12, 13, 14, 15) != 65 ||
-           bpf_fentry_test6(16, (void *)17, 18, 19, (void *)20, 21) != 111) {
-               kfree(data);
-               return ERR_PTR(-EFAULT);
-       }
+
        return data;
 }
 
+int bpf_prog_test_run_tracing(struct bpf_prog *prog,
+                             const union bpf_attr *kattr,
+                             union bpf_attr __user *uattr)
+{
+       int err = -EFAULT;
+
+       switch (prog->expected_attach_type) {
+       case BPF_TRACE_FENTRY:
+       case BPF_TRACE_FEXIT:
+               if (bpf_fentry_test1(1) != 2 ||
+                   bpf_fentry_test2(2, 3) != 5 ||
+                   bpf_fentry_test3(4, 5, 6) != 15 ||
+                   bpf_fentry_test4((void *)7, 8, 9, 10) != 34 ||
+                   bpf_fentry_test5(11, (void *)12, 13, 14, 15) != 65 ||
+                   bpf_fentry_test6(16, (void *)17, 18, 19, (void *)20, 21) != 111)
+                       goto out;
+               break;
+       default:
+               goto out;
+       }
+
+       err = 0;
+out:
+       trace_bpf_test_finish(&err);
+       return err;
+}
+
 static void *bpf_ctx_init(const union bpf_attr *kattr, u32 max_size)
 {
        void __user *data_in = u64_to_user_ptr(kattr->test.ctx_in);

diff --git a/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c b/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c
index 235ac4f..83493bd 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c
+++ b/tools/testing/selftests/bpf/prog_tests/fentry_fexit.c
@@ -1,22 +1,17 @@
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2019 Facebook */
 #include <test_progs.h>
-#include "test_pkt_access.skel.h"
 #include "fentry_test.skel.h"
 #include "fexit_test.skel.h"
 
 void test_fentry_fexit(void)
 {
-       struct test_pkt_access *pkt_skel = NULL;
        struct fentry_test *fentry_skel = NULL;
        struct fexit_test *fexit_skel = NULL;
        __u64 *fentry_res, *fexit_res;
        __u32 duration = 0, retval;
-       int err, pkt_fd, i;
+       int err, prog_fd, i;
 
-       pkt_skel = test_pkt_access__open_and_load();
-       if (CHECK(!pkt_skel, "pkt_skel_load", "pkt_access skeleton failed\n"))
-               return;
        fentry_skel = fentry_test__open_and_load();
        if (CHECK(!fentry_skel, "fentry_skel_load", "fentry skeleton failed\n"))
                goto close_prog;
@@ -31,8 +26,8 @@ void test_fentry_fexit(void)
        if (CHECK(err, "fexit_attach", "fexit attach failed: %d\n", err))
                goto close_prog;
 
-       pkt_fd = bpf_program__fd(pkt_skel->progs.test_pkt_access);
-       err = bpf_prog_test_run(pkt_fd, 1, &pkt_v6, sizeof(pkt_v6),
+       prog_fd = bpf_program__fd(fexit_skel->progs.test1);
+       err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
                                NULL, NULL, &retval, &duration);
        CHECK(err || retval, "ipv6",
              "err %d errno %d retval %d duration %d\n",
@@ -49,7 +44,6 @@ void test_fentry_fexit(void)
        }
 
 close_prog:
-       test_pkt_access__destroy(pkt_skel);
        fentry_test__destroy(fentry_skel);
        fexit_test__destroy(fexit_skel);
 }

diff --git a/tools/testing/selftests/bpf/prog_tests/fentry_test.c b/tools/testing/selftests/bpf/prog_tests/fentry_test.c
index 5cc0602..04ebbf1 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/fentry_test.c
+++ b/tools/testing/selftests/bpf/prog_tests/fentry_test.c
@@ -1,20 +1,15 @@
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2019 Facebook */
 #include <test_progs.h>
-#include "test_pkt_access.skel.h"
 #include "fentry_test.skel.h"
 
 void test_fentry_test(void)
 {
-       struct test_pkt_access *pkt_skel = NULL;
        struct fentry_test *fentry_skel = NULL;
-       int err, pkt_fd, i;
+       int err, prog_fd, i;
        __u32 duration = 0, retval;
        __u64 *result;
 
-       pkt_skel = test_pkt_access__open_and_load();
-       if (CHECK(!pkt_skel, "pkt_skel_load", "pkt_access skeleton failed\n"))
-               return;
        fentry_skel = fentry_test__open_and_load();
        if (CHECK(!fentry_skel, "fentry_skel_load", "fentry skeleton failed\n"))
                goto cleanup;
@@ -23,10 +18,10 @@ void test_fentry_test(void)
        if (CHECK(err, "fentry_attach", "fentry attach failed: %d\n", err))
                goto cleanup;
 
-       pkt_fd = bpf_program__fd(pkt_skel->progs.test_pkt_access);
-       err = bpf_prog_test_run(pkt_fd, 1, &pkt_v6, sizeof(pkt_v6),
+       prog_fd = bpf_program__fd(fentry_skel->progs.test1);
+       err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
                                NULL, NULL, &retval, &duration);
-       CHECK(err || retval, "ipv6",
+       CHECK(err || retval, "test_run",
              "err %d errno %d retval %d duration %d\n",
              err, errno, retval, duration);
 
@@ -39,5 +34,4 @@ void test_fentry_test(void)
 
 cleanup:
        fentry_test__destroy(fentry_skel);
-       test_pkt_access__destroy(pkt_skel);
 }

diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_test.c b/tools/testing/selftests/bpf/prog_tests/fexit_test.c
index d2c3655..78d7a27 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/fexit_test.c
+++ b/tools/testing/selftests/bpf/prog_tests/fexit_test.c
@@ -1,64 +1,37 @@
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2019 Facebook */
 #include <test_progs.h>
+#include "fexit_test.skel.h"
 
 void test_fexit_test(void)
 {
-       struct bpf_prog_load_attr attr = {
-               .file = "./fexit_test.o",
-       };
-
-       char prog_name[] = "fexit/bpf_fentry_testX";
-       struct bpf_object *obj = NULL, *pkt_obj;
-       int err, pkt_fd, kfree_skb_fd, i;
-       struct bpf_link *link[6] = {};
-       struct bpf_program *prog[6];
+       struct fexit_test *fexit_skel = NULL;
+       int err, prog_fd, i;
        __u32 duration = 0, retval;
-       struct bpf_map *data_map;
-       const int zero = 0;
-       u64 result[6];
+       __u64 *result;
 
-       err = bpf_prog_load("./test_pkt_access.o", BPF_PROG_TYPE_SCHED_CLS,
-                           &pkt_obj, &pkt_fd);
-       if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno))
-               return;
-       err = bpf_prog_load_xattr(&attr, &obj, &kfree_skb_fd);
-       if (CHECK(err, "prog_load fail", "err %d errno %d\n", err, errno))
-               goto close_prog;
+       fexit_skel = fexit_test__open_and_load();
+       if (CHECK(!fexit_skel, "fexit_skel_load", "fexit skeleton failed\n"))
+               goto cleanup;
 
-       for (i = 0; i < 6; i++) {
-               prog_name[sizeof(prog_name) - 2] = '1' + i;
-               prog[i] = bpf_object__find_program_by_title(obj, prog_name);
-               if (CHECK(!prog[i], "find_prog", "prog %s not found\n", prog_name))
-                       goto close_prog;
-               link[i] = bpf_program__attach_trace(prog[i]);
-               if (CHECK(IS_ERR(link[i]), "attach_trace", "failed to link\n"))
-                       goto close_prog;
-       }
-       data_map = bpf_object__find_map_by_name(obj, "fexit_te.bss");
-       if (CHECK(!data_map, "find_data_map", "data map not found\n"))
-               goto close_prog;
+       err = fexit_test__attach(fexit_skel);
+       if (CHECK(err, "fexit_attach", "fexit attach failed: %d\n", err))
+               goto cleanup;
 
-       err = bpf_prog_test_run(pkt_fd, 1, &pkt_v6, sizeof(pkt_v6),
+       prog_fd = bpf_program__fd(fexit_skel->progs.test1);
+       err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
                                NULL, NULL, &retval, &duration);
-       CHECK(err || retval, "ipv6",
+       CHECK(err || retval, "test_run",
              "err %d errno %d retval %d duration %d\n",
              err, errno, retval, duration);
 
-       err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, &result);
-       if (CHECK(err, "get_result",
-                 "failed to get output data: %d\n", err))
-               goto close_prog;
-
-       for (i = 0; i < 6; i++)
-               if (CHECK(result[i] != 1, "result", "bpf_fentry_test%d failed err %ld\n",
-                         i + 1, result[i]))
-                       goto close_prog;
+       result = (__u64 *)fexit_skel->bss;
+       for (i = 0; i < 6; i++) {
+               if (CHECK(result[i] != 1, "result",
+                         "fexit_test%d failed err %lld\n", i + 1, result[i]))
+                       goto cleanup;
+       }
 
-close_prog:
-       for (i = 0; i < 6; i++)
-               if (!IS_ERR_OR_NULL(link[i]))
-                       bpf_link__destroy(link[i]);
-       bpf_object__close(obj);
-       bpf_object__close(pkt_obj);
+cleanup:
+       fexit_test__destroy(fexit_skel);
 }