selftests/bpf: Test case for lacking CFI stub functions.

Ensure struct_ops rejects the registration of struct_ops types without
proper CFI stub functions.

bpf_test_no_cfi.ko is a module that attempts to register a struct_ops type
called "bpf_test_no_cfi_ops" with cfi_stubs of NULL and non-NULL value.
The NULL one should fail, and the non-NULL one should succeed. The module
can only be loaded successfully if these registrations yield the expected
results.

Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240222021105.1180475-3-thinker.li@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

selftests/bpf: Move is_jit_enabled() into testing_helpers

Currently, is_jit_enabled() is only used in test_progs, move it into
testing_helpers so that it can be used in test_verifier. While at it,
remove the second argument "0" of open() as Hou Tao suggested.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20240123090351.2207-2-yangtiezhu@loongson.cn

selftests/bpf: detect testing prog flags support

Various tests specify extra testing prog_flags when loading BPF
programs, like BPF_F_TEST_RND_HI32, and more recently also
BPF_F_TEST_REG_INVARIANTS. While BPF_F_TEST_RND_HI32 is old enough to
not cause much problem on older kernels, BPF_F_TEST_REG_INVARIANTS is
very fresh and unconditionally specifying it causes selftests to fail on
even slightly outdated kernels.

This breaks libbpf CI test against 4.9 and 5.15 kernels, it can break
some local development (done outside of VM), etc.

To prevent this, and guard against similar problems in the future, do
runtime detection of supported "testing flags", and only provide those
that host kernel recognizes.

Acked-by: Song Liu <song@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240109231738.575844-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Factor out get_xlated_program() helper

Both test_verifier and test_progs use get_xlated_program(), so moving
the helper into testing_helpers.h to reuse it.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20240105104819.3916743-3-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Check VLAN tag and proto in xdp_metadata

Verify, whether VLAN tag and proto are set correctly.

To simulate "stripped" VLAN tag on veth, send test packet from VLAN
interface.

Also, add TO_STR() macro for convenience.

Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Link: https://lore.kernel.org/r/20231205210847.28460-19-larysa.zaremba@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Move get_time_ns to testing_helpers.h

We'd like to have single copy of get_time_ns used b bench and test_progs,
but we can't just include bench.h, because of conflicting 'struct env'
objects.

Moving get_time_ns to testing_helpers.h which is being included by both
bench and test_progs objects.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230809083440.3209381-19-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Use un/load_bpf_testmod functions in tests

Now that we have un/load_bpf_testmod helpers in testing_helpers.h,
we can use it in other tests and save some lines.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230515133756.1658301-7-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Move test_progs helpers to testing_helpers object

Moving test_progs helpers to testing_helpers object so they can be
used from test_verifier in following changes.

Also adding missing ifndef header guard to testing_helpers.h header.

Using stderr instead of env.stderr because un/load_bpf_testmod helpers
will be used outside test_progs. Also at the point of calling them
in test_progs the std files are not hijacked yet and stderr is the
same as env.stderr.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230515133756.1658301-4-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Test_progs can read test lists from file

Improve test selection logic when using -a/-b/-d/-t options.
The list of tests to include or exclude can now be read from a file,
specified as @<filename>.

The file contains one name (or wildcard pattern) per line, and
comments beginning with # are ignored.

These options can be passed multiple times to read more than one file.

Signed-off-by: Stephen Veiss <sveiss@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230427225333.3506052-3-sveiss@meta.com

selftests/bpf: Use read_perf_max_sample_freq() in perf_event_stackmap

Currently, perf_event sample period in perf_event_stackmap is set too low
that the test fails randomly. Fix this by using the max sample frequency,
from read_perf_max_sample_freq().

Move read_perf_max_sample_freq() to testing_helpers.c. Replace the CHECK()
with if-printf, as CHECK is not available in testing_helpers.c.

Fixes: 1da4864c2b20 ("selftests/bpf: Add callchain_stackid")
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230412210423.900851-2-song@kernel.org

selftests/bpf: Improve by-name subtest selection logic in prog_tests

Improve subtest selection logic when using -t/-a/-d parameters.
In particular, more than one subtest can be specified or a
combination of tests / subtests.

-a send_signal -d send_signal/send_signal_nmi* - runs send_signal
test without nmi tests

-a send_signal/send_signal_nmi*,find_vma - runs two send_signal
subtests and find_vma test

-a 'send_signal*' -a find_vma -d send_signal/send_signal_nmi* -
runs 2 send_signal test and find_vma test. Disables two send_signal
nmi subtests

-t send_signal -t find_vma - runs two *send_signal* tests and one
*find_vma* test

This will allow us to have granular control over which subtests
to disable in the CI system instead of disabling whole tests.

Also, add new selftest to avoid possible regression when
changing prog_test test name selection logic.

Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409001750.529930-1-mykolal@fb.com

selftests/bpf: Merge test_stub.c into testing_helpers.c

Move testing prog and object load wrappers (bpf_prog_test_load and
bpf_test_load_program) into testing_helpers.{c,h} and get rid of
otherwise useless test_stub.c. Make testing_helpers.c available to
non-test_progs binaries as well.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/bpf/20211103220845.2676888-11-andrii@kernel.org

selftests/bpf: Add link detach tests for cgroup, netns, and xdp bpf_links

Add bpf_link__detach() testing to selftests for cgroup, netns, and xdp
bpf_links.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200731182830.286260-4-andriin@fb.com

selftests/bpf: Extract parse_num_list into generic testing_helpers.c

Add testing_helpers.c, which will contain generic helpers for test runners and
tests needing some common generic functionality, like parsing a set of
numbers.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200512192445.2351848-2-andriin@fb.com