tests: fix prog_info initialization in bpf-obj_get_info_by_fd-prog*

The sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &bpf_prog_get_info_attr, ...) is
called in a loop.  The bpf_prog_get_info_attr.info object is in size 104
but bpf_prog_get_info_attr.info_len is in size 168.  Hence, if the prog
is jited, the second iteration onwards will have nr_jited_ksyms == 1
which is asking the kernel to fill the
bpf_prog_get_info_attr.info.jited_ksyms and it is NULL.

* tests/bpf-obj_get_info_by_fd.c (main): Clear memory beyond prog_info
at the start of every iteration.

Co-Authored-by: Dmitry V. Levin <ldv@altlinux.org>

diff --git a/tests/bpf-obj_get_info_by_fd.c b/tests/bpf-obj_get_info_by_fd.c
index de23831a09acd6514f9f38aa97f7aed138153b1e..fba0e75b0f263c64f651f979ae4ecf71f6736103 100644 (file)
--- a/tests/bpf-obj_get_info_by_fd.c
+++ b/tests/bpf-obj_get_info_by_fd.c
@@ -345,6 +345,7 @@ main(void)
        memset(prog_info, 0, PROG_INFO_SZ);
        for (unsigned int i = 0; i < 4; i++) {
                prog_info->jited_prog_len = 0;
+               memset(prog_info + 1, 0, PROG_INFO_SZ - sizeof(*prog_info));
                switch (i) {
                case 1:
                        prog_info->xlated_prog_insns =