Re: [PATCH v4 bpf-next 05/22] selftests/bpf: Test for syscall program type

[Andrii Nakryiko <andrii.nakryiko@gmail.com>]

On Tue, May 11, 2021 at 3:36 PM Andrii Nakryiko
<andrii.nakryiko@gmail.com> wrote:
>
> On Fri, May 7, 2021 at 8:48 PM Alexei Starovoitov
> <alexei.starovoitov@gmail.com> wrote:
> >
> > From: Alexei Starovoitov <ast@kernel.org>
> >
> > bpf_prog_type_syscall is a program that creates a bpf map,
> > updates it, and loads another bpf program using bpf_sys_bpf() helper.
> >
> > Signed-off-by: Alexei Starovoitov <ast@kernel.org>
> > ---
>
> One stray CHECK() below, otherwise looks good.
>
> Acked-by: Andrii Nakryiko <andrii@kernel.org>
>
> >  .../selftests/bpf/prog_tests/syscall.c        | 49 +++++++++++++
> >  tools/testing/selftests/bpf/progs/syscall.c   | 71 +++++++++++++++++++
> >  2 files changed, 120 insertions(+)
> >  create mode 100644 tools/testing/selftests/bpf/prog_tests/syscall.c
> >  create mode 100644 tools/testing/selftests/bpf/progs/syscall.c
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/syscall.c b/tools/testing/selftests/bpf/prog_tests/syscall.c
> > new file mode 100644
> > index 000000000000..fb376c112f0c
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/prog_tests/syscall.c
> > @@ -0,0 +1,49 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/* Copyright (c) 2021 Facebook */
> > +#include <test_progs.h>
> > +#include "syscall.skel.h"
> > +
> > +struct args {
> > +       __u64 log_buf;
> > +       __u32 log_size;
> > +       int max_entries;
> > +       int map_fd;
> > +       int prog_fd;
> > +};
> > +
> > +void test_syscall(void)
> > +{
> > +       static char verifier_log[8192];
> > +       struct args ctx = {
> > +               .max_entries = 1024,
> > +               .log_buf = (uintptr_t) verifier_log,
> > +               .log_size = sizeof(verifier_log),
> > +       };
> > +       struct bpf_prog_test_run_attr tattr = {
> > +               .ctx_in = &ctx,
> > +               .ctx_size_in = sizeof(ctx),
> > +       };
> > +       struct syscall *skel = NULL;
> > +       __u64 key = 12, value = 0;
> > +       __u32 duration = 0;
> > +       int err;
> > +
> > +       skel = syscall__open_and_load();
> > +       if (CHECK(!skel, "skel_load", "syscall skeleton failed\n"))
>
> ASSERT_OK_PTR?
>
> > +               goto cleanup;
> > +
> > +       tattr.prog_fd = bpf_program__fd(skel->progs.bpf_prog);
> > +       err = bpf_prog_test_run_xattr(&tattr);
> > +       ASSERT_EQ(err, 0, "err");
> > +       ASSERT_EQ(tattr.retval, 1, "retval");
> > +       ASSERT_GT(ctx.map_fd, 0, "ctx.map_fd");
> > +       ASSERT_GT(ctx.prog_fd, 0, "ctx.prog_fd");

closing ctx.map_fd and ctx.prog_fd probably would be a good idea as well?

> > +       ASSERT_OK(memcmp(verifier_log, "processed", sizeof("processed") - 1),
> > +                 "verifier_log");
> > +
> > +       err = bpf_map_lookup_elem(ctx.map_fd, &key, &value);
> > +       ASSERT_EQ(err, 0, "map_lookup");
> > +       ASSERT_EQ(value, 34, "map lookup value");
> > +cleanup:
> > +       syscall__destroy(skel);
> > +}
>
> [...]