Re: [PATCHv6 bpf-next 11/16] selftests/bpf: Add uprobe session verifier test for return value

[Andrii Nakryiko]

On Thu, Oct 10, 2024 at 1:12 PM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Making sure uprobe.session program can return only [0,1] values.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
>  .../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
>

Nice

Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>

> 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
>