Making sure uprobe.session program can return only [0,1] values.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 .../bpf/prog_tests/uprobe_multi_test.c        |  2 ++
 .../bpf/progs/uprobe_multi_verifier.c         | 31 +++++++++++++++++++
 2 files changed, 33 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/progs/uprobe_multi_verifier.c

diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
index 284cd7fce576..e693eeb1a5a5 100644
--- a/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
+++ b/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
@@ -11,6 +11,7 @@
 #include "uprobe_multi_session.skel.h"
 #include "uprobe_multi_session_cookie.skel.h"
 #include "uprobe_multi_session_recursive.skel.h"
+#include "uprobe_multi_verifier.skel.h"
 #include "bpf/libbpf_internal.h"
 #include "testing_helpers.h"
 #include "../sdt.h"
@@ -1246,4 +1247,5 @@ void test_uprobe_multi_test(void)
 		test_session_cookie_skel_api();
 	if (test__start_subtest("session_cookie_recursive"))
 		test_session_recursive_skel_api();
+	RUN_TESTS(uprobe_multi_verifier);
 }
diff --git a/tools/testing/selftests/bpf/progs/uprobe_multi_verifier.c b/tools/testing/selftests/bpf/progs/uprobe_multi_verifier.c
new file mode 100644
index 000000000000..fe49f2cb5360
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/uprobe_multi_verifier.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/usdt.bpf.h>
+#include "bpf_misc.h"
+
+char _license[] SEC("license") = "GPL";
+
+
+SEC("uprobe.session")
+__success
+int uprobe_sesison_return_0(struct pt_regs *ctx)
+{
+	return 0;
+}
+
+SEC("uprobe.session")
+__success
+int uprobe_sesison_return_1(struct pt_regs *ctx)
+{
+	return 1;
+}
+
+SEC("uprobe.session")
+__failure
+__msg("At program exit the register R0 has smin=2 smax=2 should have been in [0, 1]")
+int uprobe_sesison_return_2(struct pt_regs *ctx)
+{
+	return 2;
+}
-- 
2.46.2