diff --git a/scripts/recursion.pl b/scripts/recursion.pl
index d75a4ef44..2c39c1434 100755
--- a/scripts/recursion.pl
+++ b/scripts/recursion.pl
@@ -16,7 +16,8 @@ use open qw(:std utf8);
 
 # exclude functions that are ok:
 # - mpi_write_hlp: bounded by size of mpi, a compile-time constant
-my $known_ok = qr/mpi_write_hlp/;
+# - x509_crt_verify_child: bounded by POLARSSL_X509_MAX_INTERMEDIATE_CA
+my $known_ok = qr/mpi_write_hlp|x509_crt_verify_child/;
 
 my $cur_name;
 my $inside;