On Fri, Aug 25, 2017 at 02:39:57PM -0700, Jakub Kicinski wrote:
> Add a basic test for checking whether kernel is populating
> the jited and xlated BPF images. It was used to confirm
> the behaviour change from commit d777b2ddbecf ("bpf: don't
> zero out the info struct in bpf_obj_get_info_by_fd()"),
> which made bpf_obj_get_info_by_fd() usable for retrieving
> the image dumps.
Acked-by: Martin KaFai Lau <[email protected]>
>
> Signed-off-by: Jakub Kicinski <[email protected]>
> ---
> tools/testing/selftests/bpf/test_progs.c | 16 ++++++++++++----
> 1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/test_progs.c
> b/tools/testing/selftests/bpf/test_progs.c
> index 1cb037803679..11ee25cea227 100644
> --- a/tools/testing/selftests/bpf/test_progs.c
> +++ b/tools/testing/selftests/bpf/test_progs.c
> @@ -279,7 +279,7 @@ static void test_bpf_obj_id(void)
> /* +1 to test for the info_len returned by kernel */
> struct bpf_prog_info prog_infos[nr_iters + 1];
> struct bpf_map_info map_infos[nr_iters + 1];
> - char jited_insns[128], xlated_insns[128];
> + char jited_insns[128], xlated_insns[128], zeros[128];
> __u32 i, next_id, info_len, nr_id_found, duration = 0;
> int sysctl_fd, jit_enabled = 0, err = 0;
> __u64 array_value;
> @@ -305,6 +305,7 @@ static void test_bpf_obj_id(void)
> objs[i] = NULL;
>
> /* Check bpf_obj_get_info_by_fd() */
> + bzero(zeros, sizeof(zeros));
> for (i = 0; i < nr_iters; i++) {
> err = bpf_prog_load(file, BPF_PROG_TYPE_SOCKET_FILTER,
> &objs[i], &prog_fds[i]);
> @@ -318,6 +319,8 @@ static void test_bpf_obj_id(void)
> /* Check getting prog info */
> info_len = sizeof(struct bpf_prog_info) * 2;
> bzero(&prog_infos[i], info_len);
> + bzero(jited_insns, sizeof(jited_insns));
> + bzero(xlated_insns, sizeof(xlated_insns));
> prog_infos[i].jited_prog_insns = ptr_to_u64(jited_insns);
> prog_infos[i].jited_prog_len = sizeof(jited_insns);
> prog_infos[i].xlated_prog_insns = ptr_to_u64(xlated_insns);
> @@ -328,15 +331,20 @@ static void test_bpf_obj_id(void)
> prog_infos[i].type != BPF_PROG_TYPE_SOCKET_FILTER ||
> info_len != sizeof(struct bpf_prog_info) ||
> (jit_enabled && !prog_infos[i].jited_prog_len) ||
> - !prog_infos[i].xlated_prog_len,
> + (jit_enabled &&
> + !memcmp(jited_insns, zeros, sizeof(zeros))) ||
> + !prog_infos[i].xlated_prog_len ||
> + !memcmp(xlated_insns, zeros, sizeof(zeros)),
> "get-prog-info(fd)",
> - "err %d errno %d i %d type %d(%d) info_len %u(%lu)
> jit_enabled %d jited_prog_len %u xlated_prog_len %u\n",
> + "err %d errno %d i %d type %d(%d) info_len %u(%lu)
> jit_enabled %d jited_prog_len %u xlated_prog_len %u jited_prog %d xlated_prog
> %d\n",
> err, errno, i,
> prog_infos[i].type, BPF_PROG_TYPE_SOCKET_FILTER,
> info_len, sizeof(struct bpf_prog_info),
> jit_enabled,
> prog_infos[i].jited_prog_len,
> - prog_infos[i].xlated_prog_len))
> + prog_infos[i].xlated_prog_len,
> + !!memcmp(jited_insns, zeros, sizeof(zeros)),
> + !!memcmp(xlated_insns, zeros, sizeof(zeros))))
> goto done;
>
> map_fds[i] = bpf_find_map(__func__, objs[i], "test_map_id");
> --
> 2.11.0
>
