selftests/bpf: Store BPF object files with .bpf.o extension

BPF object files are, in a way, the final artifact produced as part of
the ahead-of-time compilation process. That makes them somewhat special
compared to "regular" object files, which are a intermediate build
artifacts that can typically be removed safely. As such, it can make
sense to name them differently to make it easier to spot this difference
at a glance.

Among others, libbpf-bootstrap [0] has established the extension .bpf.o
for BPF object files. It seems reasonable to follow this example and
establish the same denomination for selftest build artifacts. To that
end, this change adjusts the corresponding part of the build system and
the test programs loading BPF object files to work with .bpf.o files.

[0] https://github.com/libbpf/libbpf-bootstrap

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220901222253.1199242-1-deso@posteo.net

selftests/bpf: Fix clang compilation errors

llvm upstream patch ([1]) added to issue warning for code like
void test() {
int j = 0;
for (int i = 0; i < 1000; i++)
j++;
return;
}

This triggered several errors in selftests/bpf build since
compilation flag -Werror is used.
...
test_lpm_map.c:212:15: error: variable 'n_matches' set but not used [-Werror,-Wunused-but-set-variable]
size_t i, j, n_matches, n_matches_after_delete, n_nodes, n_lookups;
^
test_lpm_map.c:212:26: error: variable 'n_matches_after_delete' set but not used [-Werror,-Wunused-but-set-variable]
size_t i, j, n_matches, n_matches_after_delete, n_nodes, n_lookups;
^
...
prog_tests/get_stack_raw_tp.c:32:15: error: variable 'cnt' set but not used [-Werror,-Wunused-but-set-variable]
static __u64 cnt;
^
...

For test_lpm_map.c, 'n_matches'/'n_matches_after_delete' are changed to be volatile
in order to silent the warning. I didn't remove these two declarations since
they are referenced in a commented code which might be used by people in certain
cases. For get_stack_raw_tp.c, the variable 'cnt' is removed.

[1] https://reviews.llvm.org/D122271

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220325200304.2915588-1-yhs@fb.com

selftests/bpf: Stop using bpf_object__find_program_by_title API.

bpf_object__find_program_by_title is going to be deprecated. Replace
all use cases in tools/testing/selftests/bpf with
bpf_object__find_program_by_name or bpf_object__for_each_program.

Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211214035931.1148209-2-kuifeng@fb.com

selftests/bpf: Prevent misaligned memory access in get_stack_raw_tp test

Perfbuf doesn't guarantee 8-byte alignment of the data like BPF ringbuf
does, so struct get_stack_trace_t can arrive not properly aligned for
subsequent u64 accesses. Easiest fix is to just copy data locally.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211124002325.1737739-10-andrii@kernel.org

selftests/bpf: Migrate all deprecated perf_buffer uses

Migrate all old-style perf_buffer__new() and perf_buffer__new_raw()
calls to new v1.0+ variants.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211111053624.190580-7-andrii@kernel.org

selftests/bpf: Use explicit bpf_prog_test_load() calls everywhere

-Dbpf_prog_load_deprecated=bpf_prog_test_load trick is both ugly and
breaks when deprecation goes into effect due to macro magic. Convert all
the uses to explicit bpf_prog_test_load() calls which avoid deprecation
errors and makes everything less magical.

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/20211103220845.2676888-12-andrii@kernel.org

selftests/bpf: Turn on libbpf 1.0 mode and fix all IS_ERR checks

Turn ony libbpf 1.0 mode. Fix all the explicit IS_ERR checks that now will be
broken because libbpf returns NULL on error (and sets errno). Fix
ASSERT_OK_PTR and ASSERT_ERR_PTR to work for both old mode and new modes and
use them throughout selftests. This is trivial to do by using
libbpf_get_error() API that all libbpf users are supposed to use, instead of
IS_ERR checks.

A bunch of checks also did explicit -1 comparison for various fd-returning
APIs. Such checks are replaced with >= 0 or < 0 cases.

There were also few misuses of bpf_object__find_map_by_name() in test_maps.
Those are fixed in this patch as well.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210525035935.1461796-3-andrii@kernel.org

bpf: Test_progs, add test to catch retval refine error handling

Before this series the verifier would clamp return bounds of
bpf_get_stack() to [0, X] and this led the verifier to believe
that a JMP_JSLT 0 would be false and so would prune that path.

The result is anything hidden behind that JSLT would be unverified.
Add a test to catch this case by hiding an goto pc-1 behind the
check which will cause an infinite loop if not rejected.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560423908.10843.11783152347709008373.stgit@john-Precision-5820-Tower

selftests/bpf: test_progs: remove global fail/success counts

Now that we have a global per-test/per-environment state, there
is no longer need to have global fail/success counters (and there
is no need to save/get the diff before/after the test).

Introduce CHECK_FAIL macro (suggested by Andrii) and covert existing tests
to it. CHECK_FAIL uses new test__fail() to record the failure.

Cc: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

selftests/bpf: abstract away test log output

This patch changes how test output is printed out. By default, if test
had no errors, the only output will be a single line with test number,
name, and verdict at the end, e.g.:

#31 xdp:OK

If test had any errors, all log output captured during test execution
will be output after test completes.

It's possible to force output of log with `-v` (`--verbose`) option, in
which case output won't be buffered and will be output immediately.

To support this, individual tests are required to use helper methods for
logging: `test__printf()` and `test__vprintf()`.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: convert test_get_stack_raw_tp to perf_buffer API

Convert test_get_stack_raw_tp test to new perf_buffer API.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

samples, selftests/bpf: add NULL check for ksym_search

Since, ksym_search added with verification logic for symbols existence,
it could return NULL when the kernel symbols are not loaded.

This commit will add NULL check logic after ksym_search.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

selftests: bpf: break up test_progs - tracepoint

Move tracepoint prog tests into separate files.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>