From 28d2459d4b65110d6e6c1e18470ce7dcb7113282 Mon Sep 17 00:00:00 2001
From: Zaahir Moolla <moollaza@fastmail.fm>
Date: Wed, 28 Nov 2018 13:02:26 -0500
Subject: [PATCH] Factors & Prime Factors: Limit input size to <= 1M (#4669)

* Limit input size to Factors IA

* Limit input size of PrimeFactors Goodie
---
 lib/DDG/Goodie/Factors.pm      | 7 ++++++-
 lib/DDG/Goodie/PrimeFactors.pm | 2 ++
 t/Factors.t                    | 1 +
 t/PrimeFactors.t               | 9 +++++----
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/lib/DDG/Goodie/Factors.pm b/lib/DDG/Goodie/Factors.pm
index 982c0694b..f565b1877 100755
--- a/lib/DDG/Goodie/Factors.pm
+++ b/lib/DDG/Goodie/Factors.pm
@@ -22,7 +22,12 @@ handle remainder => sub {
     # query number is negative, find and include negative factors.
     my $negative  = $1;
     my $query_mag = $2;
-    my @factors   = divisors($query_mag);
+
+    # max input value of 1M
+    # anything big takes too long to calculate
+    return unless $query_mag <= 1000000;
+
+    my @factors = divisors($query_mag);
 
     unshift @factors, sort { $a <=> $b } map { -$_ } @factors
         if $negative;
diff --git a/lib/DDG/Goodie/PrimeFactors.pm b/lib/DDG/Goodie/PrimeFactors.pm
index cbfc78c52..8201b2165 100644
--- a/lib/DDG/Goodie/PrimeFactors.pm
+++ b/lib/DDG/Goodie/PrimeFactors.pm
@@ -102,6 +102,8 @@ handle remainder => sub {
     # Extract only the number from the remainder
     $_ =~ s/\D+//;
 
+    return unless $_ <= 1000000;
+
     my @factors = factor_exp($_);
 
     # Exit if we didn't find anything.
diff --git a/t/Factors.t b/t/Factors.t
index 92c817c2f..d49326ec3 100755
--- a/t/Factors.t
+++ b/t/Factors.t
@@ -56,6 +56,7 @@ ddg_goodie_test(
         '-12',
         '-12, -6, -4, -3, -2, -1, 1, 2, 3, 4, 6, 12'
     ),
+    'factors of 999999999' => undef,
     'factors of 2.4'  => undef,
     'factors of fear' => undef,
 );
diff --git a/t/PrimeFactors.t b/t/PrimeFactors.t
index 0c9041d3b..8e3953e0a 100644
--- a/t/PrimeFactors.t
+++ b/t/PrimeFactors.t
@@ -27,9 +27,9 @@ sub build_answer {
 }
 
 ddg_goodie_test(
-	[qw(
-		DDG::Goodie::PrimeFactors
-	)],
+    [qw(
+        DDG::Goodie::PrimeFactors
+    )],
     '72 prime factors' => test_zci('The prime factorization of 72 is 2^3 × 3^2',
                                     build_answer('72 - Prime Factors', '2³ × 3²')),
     'prime factors of 111' => test_zci('The prime factorization of 111 is 3 × 37',
@@ -52,7 +52,8 @@ ddg_goodie_test(
                                     build_answer(undef, '83 is a prime number')),
     'is 83 a prime number' => test_zci('83 is a prime number',
                                     build_answer(undef, '83 is a prime number')),
-    'optimus prime 45' => undef
+    'optimus prime 45' => undef,
+    'prime factors of 9999999' => undef
 );
 
 done_testing;