selftests/bpf: Add bpf_get_func_ip test for uprobe inside function

Adding get_func_ip test for uprobe inside function that validates
the get_func_ip helper returns correct probe address value.

Tested-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230807085956.2344866-4-jolsa@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c b/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c
index 114cdbc..c40242d 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c
+++ b/tools/testing/selftests/bpf/prog_tests/get_func_ip_test.c
@@ -51,11 +51,17 @@ cleanup:
        get_func_ip_test__destroy(skel);
 }
 
-/* test6 is x86_64 specific because of the instruction
- * offset, disabling it for all other archs
- */
 #ifdef __x86_64__
-static void test_function_body(void)
+extern void uprobe_trigger_body(void);
+asm(
+".globl uprobe_trigger_body\n"
+".type uprobe_trigger_body, @function\n"
+"uprobe_trigger_body:\n"
+"      nop\n"
+"      ret\n"
+);
+
+static void test_function_body_kprobe(void)
 {
        struct get_func_ip_test *skel = NULL;
        LIBBPF_OPTS(bpf_test_run_opts, topts);
@@ -67,6 +73,9 @@ static void test_function_body(void)
        if (!ASSERT_OK_PTR(skel, "get_func_ip_test__open"))
                return;
 
+       /* test6 is x86_64 specific and is disabled by default,
+        * enable it for body test.
+        */
        bpf_program__set_autoload(skel->progs.test6, true);
 
        err = get_func_ip_test__load(skel);
@@ -90,6 +99,35 @@ cleanup:
        bpf_link__destroy(link6);
        get_func_ip_test__destroy(skel);
 }
+
+static void test_function_body_uprobe(void)
+{
+       struct get_func_ip_uprobe_test *skel = NULL;
+       int err;
+
+       skel = get_func_ip_uprobe_test__open_and_load();
+       if (!ASSERT_OK_PTR(skel, "get_func_ip_uprobe_test__open_and_load"))
+               return;
+
+       err = get_func_ip_uprobe_test__attach(skel);
+       if (!ASSERT_OK(err, "get_func_ip_test__attach"))
+               goto cleanup;
+
+       skel->bss->uprobe_trigger_body = (unsigned long) uprobe_trigger_body;
+
+       uprobe_trigger_body();
+
+       ASSERT_EQ(skel->bss->test1_result, 1, "test1_result");
+
+cleanup:
+       get_func_ip_uprobe_test__destroy(skel);
+}
+
+static void test_function_body(void)
+{
+       test_function_body_kprobe();
+       test_function_body_uprobe();
+}
 #else
 #define test_function_body()
 #endif

diff --git a/tools/testing/selftests/bpf/progs/get_func_ip_uprobe_test.c b/tools/testing/selftests/bpf/progs/get_func_ip_uprobe_test.c
new file mode 100644 (file)
index 0000000..052f8a4
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/get_func_ip_uprobe_test.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+unsigned long uprobe_trigger_body;
+
+__u64 test1_result = 0;
+SEC("uprobe//proc/self/exe:uprobe_trigger_body+1")
+int BPF_UPROBE(test1)
+{
+       __u64 addr = bpf_get_func_ip(ctx);
+
+       test1_result = (const void *) addr == (const void *) uprobe_trigger_body + 1;
+       return 0;
+}