diff --git a/tests/scripts/recursion.pl b/tests/scripts/recursion.pl
index 0c40581..431e592 100755
--- a/tests/scripts/recursion.pl
+++ b/tests/scripts/recursion.pl
@@ -16,7 +16,8 @@
 
 # exclude functions that are ok:
 # - mpi_write_hlp: bounded by size of mbedtls_mpi, a compile-time constant
-my $known_ok = qr/mpi_write_hlp/;
+# - x509_crt_verify_child: bounded by MBEDTLS_X509_MAX_INTERMEDIATE_CA
+my $known_ok = qr/mpi_write_hlp|x509_crt_verify_child/;
 
 my $cur_name;
 my $inside;