1 files changed, 54 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/iters.c b/tools/testing/selftests/bpf/progs/iters.c
index 16bdc3e25591..ef70b88bccb2 100644
--- a/tools/testing/selftests/bpf/progs/iters.c
+++ b/tools/testing/selftests/bpf/progs/iters.c
@@ -1432,4 +1432,58 @@ int iter_arr_with_actual_elem_count(const void *ctx)
 	return sum;
 }
 
+__u32 upper, select_n, result;
+__u64 global;
+
+static __noinline bool nest_2(char *str)
+{
+	/* some insns (including branch insns) to ensure stacksafe() is triggered
+	 * in nest_2(). This way, stacksafe() can compare frame associated with nest_1().
+	 */
+	if (str[0] == 't')
+		return true;
+	if (str[1] == 'e')
+		return true;
+	if (str[2] == 's')
+		return true;
+	if (str[3] == 't')
+		return true;
+	return false;
+}
+
+static __noinline bool nest_1(int n)
+{
+	/* case 0: allocate stack, case 1: no allocate stack */
+	switch (n) {
+	case 0: {
+		char comm[16];
+
+		if (bpf_get_current_comm(comm, 16))
+			return false;
+		return nest_2(comm);
+	}
+	case 1:
+		return nest_2((char *)&global);
+	default:
+		return false;
+	}
+}
+
+SEC("raw_tp")
+__success
+int iter_subprog_check_stacksafe(const void *ctx)
+{
+	long i;
+
+	bpf_for(i, 0, upper) {
+		if (!nest_1(select_n)) {
+			result = 1;
+			return 0;
+		}
+	}
+
+	result = 2;
+	return 0;
+}
+
 char _license[] SEC("license") = "GPL";