From: Alexander Ebert <ebert@woltlab.com>
Date: Fri, 19 Jan 2024 10:54:28 +0000 (+0100)
Subject: Safeguard against invalid EXIF values
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c5bb7db7e5dc4529953f9241d2f9a8175af1922e;p=GitHub%2FWoltLab%2FWCF.git

Safeguard against invalid EXIF values

See https://www.woltlab.com/community/thread/304312-fehlermeldung-division-by-zero-bei-anzeigen-aktualisieren-galerie-bilder-aktuali/
---

diff --git a/wcfsetup/install/files/lib/util/ExifUtil.class.php b/wcfsetup/install/files/lib/util/ExifUtil.class.php
index bdee394585..bc2d515807 100644
--- a/wcfsetup/install/files/lib/util/ExifUtil.class.php
+++ b/wcfsetup/install/files/lib/util/ExifUtil.class.php
@@ -300,6 +300,12 @@ final class ExifUtil
         $denonimator = $data[1];
         $gcd = self::gcd($numerator, $denonimator);
 
+        // When the numerator equals 0 (e.g. 0/10), then the resulting GCD will
+        // equal null, resulting in a division by zero below.
+        if ($gcd === 0) {
+            return $rational;
+        }
+
         return \sprintf('%d/%d', \intdiv($numerator, $gcd), \intdiv($denonimator, $gcd));
     }