selftests/bpf: Fix repeat option when kfunc_call verification fails

There is no way where topts.repeat can be set to 1 when tc_test fails.
Fix the typo where the break statement slipped by one line.

Fixes: fb66223a244f ("selftests/bpf: add test for accessing ctx from syscall program type")
Signed-off-by: Yipeng Zou <zouyipeng@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Li Zetao <lizetao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230814031434.3077944-1-zouyipeng@huawei.com

selftests/bpf: Add testcase for static kfunc with unused arg

kfuncs are allowed to be static, or not use one or more of their
arguments. For example, bpf_xdp_metadata_rx_hash() in net/core/xdp.c is
meant to be implemented by drivers, with the default implementation just
returning -EOPNOTSUPP. As described in [0], such kfuncs can have their
arguments elided, which can cause BTF encoding to be skipped. The new
__bpf_kfunc macro should address this, and this patch adds a selftest
which verifies that a static kfunc with at least one unused argument can
still be encoded and invoked by a BPF program.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230201173016.342758-5-void@manifault.com

selftests/bpf: Add a sign-extension test for kfuncs

s390x ABI requires the caller to zero- or sign-extend the arguments.
eBPF already deals with zero-extension (by definition of its ABI), but
not with sign-extension.

Add a test to cover that potentially problematic area.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-15-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Add tests for kfunc returning a memory pointer

We add 2 new kfuncs that are following the RET_PTR_TO_MEM
capability from the previous commit.
Then we test them in selftests:
the first tests are testing valid case, and are not failing,
and the later ones are actually preventing the program to be loaded
because they are wrong.

To work around that, we mark the failing ones as not autoloaded
(with SEC("?tc")), and we manually enable them one by one, ensuring
the verifier rejects them.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20220906151303.2780789-8-benjamin.tissoires@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: add test for accessing ctx from syscall program type

We need to also export the kfunc set to the syscall program type,
and then add a couple of eBPF programs that are testing those calls.

The first one checks for valid access, and the second one is OK
from a static analysis point of view but fails at run time because
we are trying to access outside of the allocated memory.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20220906151303.2780789-5-benjamin.tissoires@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: regroup and declare similar kfuncs selftests in an array

Similar to tools/testing/selftests/bpf/prog_tests/dynptr.c:
we declare an array of tests that we run one by one in a for loop.

Followup patches will add more similar-ish tests, so avoid a lot of copy
paste by grouping the declaration in an array.

For light skeletons, we have to rely on the offsetof() macro so we can
statically declare which program we are using.
In the libbpf case, we can rely on bpf_object__find_program_by_name().
So also change the Makefile to generate both light skeletons and normal
ones.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220906151303.2780789-2-benjamin.tissoires@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Fix spelling mistake.

There is a spelling mistake in an ASSERT_OK literal string. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Mykola Lysenko <mykolal@fb.com>
Link: https://lore.kernel.org/r/20220817213242.101277-1-colin.i.king@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: add destructive kfunc test

Add a test checking that programs calling destructive kfuncs can only do
so if they have CAP_SYS_BOOT capabilities.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Link: https://lore.kernel.org/r/20220810065905.475418-4-asavkov@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Migrate from bpf_prog_test_run

bpf_prog_test_run is being deprecated in favor of the OPTS-based
bpf_prog_test_run_opts.
We end up unable to use CHECK in most cases, so replace usages with
ASSERT_* calls.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220202235423.1097270-2-delyank@fb.com

selftests/bpf: Extend kfunc selftests

Use the prog_test kfuncs to test the referenced PTR_TO_BTF_ID kfunc
support, and PTR_TO_CTX, PTR_TO_MEM argument passing support. Also
testing the various failure cases for invalid kfunc prototypes.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-10-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Add lskel version of kfunc test.

Add light skeleton version of kfunc_call_test_subprog test.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-13-alexei.starovoitov@gmail.com

selftests/bpf: Add weak/typeless ksym test for light skeleton

Also, avoid using CO-RE features, as lskel doesn't support CO-RE, yet.
Include both light and libbpf skeleton in same file to test both of them
together.

In c48e51c8b07a ("bpf: selftests: Add selftests for module kfunc support"),
I added support for generating both lskel and libbpf skel for a BPF
object, however the name parameter for bpftool caused collisions when
included in same file together. This meant that every test needed a
separate file for a libbpf/light skeleton separation instead of
subtests.

Change that by appending a "_lskel" suffix to the name for files using
light skeleton, and convert all existing users.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211028063501.2239335-7-memxor@gmail.com

bpf: selftests: Add sk_state to bpf_tcp_helpers.h

Add sk_state define to bpf_tcp_helpers.h. Rename the existing
global variable "sk_state" in the kfunc_call test to "sk_state_res".

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210824173013.3977316-1-kafai@fb.com

selftests/bpf: Convert few tests to light skeleton.

Convert few tests that don't use CO-RE to light skeleton.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210514003623.28033-19-alexei.starovoitov@gmail.com

bpf: selftests: Add kfunc_call test

This patch adds a few kernel function bpf_kfunc_call_test*() for the
selftest's test_run purpose. They will be allowed for tc_cls prog.

The selftest calling the kernel function bpf_kfunc_call_test*()
is also added in this patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015252.1551395-1-kafai@fb.com