From 68c3438474ddd857d5e21f8da0c0cf398e6b3812 Mon Sep 17 00:00:00 2001
From: Kevin Chung <kchung@ctfd.io>
Date: Wed, 8 Feb 2023 13:22:16 -0500
Subject: [PATCH] Fix issue where dynamic challenges break if the decay is 0
 (#2255)

* Fix issue where dynamic challenges break if the decay is 0
* Prevent users from adding a decay limit of 0 to dynamic value challenges
---
 CTFd/plugins/dynamic_challenges/__init__.py        | 5 +++++
 CTFd/plugins/dynamic_challenges/assets/create.html | 2 +-
 CTFd/plugins/dynamic_challenges/assets/update.html | 2 +-
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/CTFd/plugins/dynamic_challenges/__init__.py b/CTFd/plugins/dynamic_challenges/__init__.py
index 24591428..ab7aaca2 100644
--- a/CTFd/plugins/dynamic_challenges/__init__.py
+++ b/CTFd/plugins/dynamic_challenges/__init__.py
@@ -69,6 +69,11 @@ class DynamicValueChallenge(BaseChallenge):
             # We subtract -1 to allow the first solver to get max point value
             solve_count -= 1
 
+        # Handle situations where admins have entered a 0 decay
+        # This is invalid as it can cause a division by zero
+        if challenge.decay == 0:
+            challenge.decay = 1
+
         # It is important that this calculation takes into account floats.
         # Hence this file uses from __future__ import division
         value = (
diff --git a/CTFd/plugins/dynamic_challenges/assets/create.html b/CTFd/plugins/dynamic_challenges/assets/create.html
index c6e261e8..d8f3e2a1 100644
--- a/CTFd/plugins/dynamic_challenges/assets/create.html
+++ b/CTFd/plugins/dynamic_challenges/assets/create.html
@@ -25,7 +25,7 @@
 			The amount of solves before the challenge reaches its minimum value
 		</small>
 	</label>
-	<input type="number" class="form-control" name="decay" placeholder="Enter decay limit" required>
+	<input type="number" class="form-control" name="decay" min="1" placeholder="Enter decay limit" required>
 </div>
 
 <div class="form-group">
diff --git a/CTFd/plugins/dynamic_challenges/assets/update.html b/CTFd/plugins/dynamic_challenges/assets/update.html
index 48a0711f..d432fe34 100644
--- a/CTFd/plugins/dynamic_challenges/assets/update.html
+++ b/CTFd/plugins/dynamic_challenges/assets/update.html
@@ -25,7 +25,7 @@
 			The amount of solves before the challenge reaches its minimum value
 		</small>
 	</label>
-	<input type="number" class="form-control chal-decay" name="decay" value="{{ challenge.decay }}" required>
+	<input type="number" class="form-control chal-decay" min="1" name="decay" value="{{ challenge.decay }}" required>
 </div>
 
 <div class="form-group">