Adding test to check we can't attach standard kprobe program that
writes to the context.
It's x86_64 specific test.
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
.../selftests/bpf/prog_tests/attach_probe.c | 28 +++++++++++++++++++
.../selftests/bpf/progs/kprobe_write_ctx.c | 15 ++++++++++
2 files changed, 43 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/kprobe_write_ctx.c
diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
index cabc51c2ca6b..9e77e5da7097 100644
--- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
+++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
@@ -3,6 +3,7 @@
#include "test_attach_kprobe_sleepable.skel.h"
#include "test_attach_probe_manual.skel.h"
#include "test_attach_probe.skel.h"
+#include "kprobe_write_ctx.skel.h"
/* this is how USDT semaphore is actually defined, except volatile modifier */
volatile unsigned short uprobe_ref_ctr __attribute__((unused))
__attribute((section(".probes")));
@@ -201,6 +202,31 @@ static void test_attach_kprobe_long_event_name(void)
test_attach_probe_manual__destroy(skel);
}
+#ifdef __x86_64__
+/* attach kprobe/kretprobe long event name testings */
+static void test_attach_kprobe_write_ctx(void)
+{
+ struct kprobe_write_ctx *skel = NULL;
+ struct bpf_link *link = NULL;
+
+ skel = kprobe_write_ctx__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "kprobe_write_ctx__open_and_load"))
+ return;
+
+ link = bpf_program__attach_kprobe_opts(skel->progs.kprobe_write_ctx,
+ "bpf_fentry_test1", NULL);
+ if (!ASSERT_ERR_PTR(link, "bpf_program__attach_kprobe_opts"))
+ bpf_link__destroy(link);
+
+ kprobe_write_ctx__destroy(skel);
+}
+#else
+static void test_attach_kprobe_write_ctx(void)
+{
+ test__skip();
+}
+#endif
+
static void test_attach_probe_auto(struct test_attach_probe *skel)
{
struct bpf_link *uprobe_err_link;
@@ -406,6 +432,8 @@ void test_attach_probe(void)
test_attach_uprobe_long_event_name();
if (test__start_subtest("kprobe-long_name"))
test_attach_kprobe_long_event_name();
+ if (test__start_subtest("kprobe-write-ctx"))
+ test_attach_kprobe_write_ctx();
cleanup:
test_attach_probe__destroy(skel);
diff --git a/tools/testing/selftests/bpf/progs/kprobe_write_ctx.c
b/tools/testing/selftests/bpf/progs/kprobe_write_ctx.c
new file mode 100644
index 000000000000..4621a5bef4e2
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/kprobe_write_ctx.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+#if defined(__TARGET_ARCH_x86)
+SEC("kprobe")
+int kprobe_write_ctx(struct pt_regs *ctx)
+{
+ ctx->ax = 0;
+ return 0;
+}
+#endif
--
2.51.0
