On Sun, Mar 20, 2022 at 8:56 AM Kumar Kartikeya Dwivedi
<memxor@xxxxxxxxx> wrote:
>
> This uses the __kptr and __kptr_ref macros as well, and tries to test
> the stuff that is supposed to work, since we have negative tests in
> test_verifier suite. Also include some code to test map-in-map support,
> such that the inner_map_meta matches the kptr_off_tab of map added as
> element.
>
> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
> ---
> .../selftests/bpf/prog_tests/map_kptr.c | 20 ++
> tools/testing/selftests/bpf/progs/map_kptr.c | 194 ++++++++++++++++++
> 2 files changed, 214 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/map_kptr.c
> create mode 100644 tools/testing/selftests/bpf/progs/map_kptr.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/map_kptr.c b/tools/testing/selftests/bpf/prog_tests/map_kptr.c
> new file mode 100644
> index 000000000000..688732295ce9
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/map_kptr.c
> @@ -0,0 +1,20 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <test_progs.h>
> +
> +#include "map_kptr.skel.h"
> +
> +void test_map_kptr(void)
> +{
> + struct map_kptr *skel;
> + char buf[24];
> + int key = 0;
> +
> + skel = map_kptr__open_and_load();
> + if (!ASSERT_OK_PTR(skel, "map_kptr__open_and_load"))
> + return;
> + ASSERT_OK(bpf_map_update_elem(bpf_map__fd(skel->maps.hash_map), &key, buf, 0),
> + "bpf_map_update_elem hash_map");
> + ASSERT_OK(bpf_map_update_elem(bpf_map__fd(skel->maps.hash_malloc_map), &key, buf, 0),
> + "bpf_map_update_elem hash_malloc_map");
nit: it's quite messy and verbose, please do the operation outside of
ASSERT_OK() and just validate error:
err = bpf_map_update_elem(...);
ASSERT_OK(err, "hash_map_update");
And keep those ASSERT_XXX() string descriptors relatively short (see
how they are used internally in ASSERT_XXX() macros).
> + map_kptr__destroy(skel);
> +}
[...]
> +
> +extern struct prog_test_ref_kfunc *bpf_kfunc_call_test_acquire(unsigned long *sp) __ksym;
> +extern struct prog_test_ref_kfunc *
> +bpf_kfunc_call_test_kptr_get(struct prog_test_ref_kfunc **p, int a, int b) __ksym;
> +extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
> +
> +static __always_inline
nit: no need for __always_inline everywhere, just `static void` will
do the right thing.
> +void test_kptr_unref(struct map_value *v)
> +{
> + struct prog_test_ref_kfunc *p;
> +
> + p = v->unref_ptr;
> + /* store untrusted_ptr_or_null_ */
> + v->unref_ptr = p;
> + if (!p)
> + return;
> + if (p->a + p->b > 100)
> + return;
> + /* store untrusted_ptr_ */
> + v->unref_ptr = p;
> + /* store NULL */
> + v->unref_ptr = NULL;
> +}
> +
[...]
