[PATCH bpf v2 2/2] selftests/bpf: Add tests for iter arg check

[Kumar Kartikeya Dwivedi <memxor@gmail.com>]

Add selftests to cover argument type check for iterator kfuncs, and
cover all three kinds (new, next, destroy). Without the fix in the
previous patch, the selftest would not cause a verifier error.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
---
 tools/testing/selftests/bpf/progs/iters.c | 26 +++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/tools/testing/selftests/bpf/progs/iters.c b/tools/testing/selftests/bpf/progs/iters.c
index ef70b88bccb2..7c969c127573 100644
--- a/tools/testing/selftests/bpf/progs/iters.c
+++ b/tools/testing/selftests/bpf/progs/iters.c
@@ -1486,4 +1486,30 @@ int iter_subprog_check_stacksafe(const void *ctx)
 	return 0;
 }
 
+struct bpf_iter_num global_it;
+
+SEC("raw_tp")
+__failure __msg("arg#0 expected pointer to an iterator on stack")
+int iter_new_bad_arg(const void *ctx)
+{
+	bpf_iter_num_new(&global_it, 0, 1);
+	return 0;
+}
+
+SEC("raw_tp")
+__failure __msg("arg#0 expected pointer to an iterator on stack")
+int iter_next_bad_arg(const void *ctx)
+{
+	bpf_iter_num_next(&global_it);
+	return 0;
+}
+
+SEC("raw_tp")
+__failure __msg("arg#0 expected pointer to an iterator on stack")
+int iter_destroy_bad_arg(const void *ctx)
+{
+	bpf_iter_num_destroy(&global_it);
+	return 0;
+}
+
 char _license[] SEC("license") = "GPL";
-- 
2.43.5