From 4b5b8fc564aebd8daf7193c4e828bd0db18c8c25 Mon Sep 17 00:00:00 2001
From: Tim Ledbetter <timledbetter@gmail.com>
Date: Thu, 26 Oct 2023 23:47:08 +0100
Subject: [PATCH] LibGfx: Use safe version of `count_leading_zeroes()` in WOFF
 parsers

This guards against undefined behavior when zero is given as an
argument.
---
 Userland/Libraries/LibGfx/Font/WOFF/Font.cpp  | 2 +-
 Userland/Libraries/LibGfx/Font/WOFF2/Font.cpp | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Userland/Libraries/LibGfx/Font/WOFF/Font.cpp b/Userland/Libraries/LibGfx/Font/WOFF/Font.cpp
index cebd901acc..a7ac8b5efd 100644
--- a/Userland/Libraries/LibGfx/Font/WOFF/Font.cpp
+++ b/Userland/Libraries/LibGfx/Font/WOFF/Font.cpp
@@ -65,7 +65,7 @@ static u16 pow_2_less_than_or_equal(u16 x)
 {
     VERIFY(x > 0);
     VERIFY(x < 32769);
-    return 1 << (sizeof(u16) * 8 - count_leading_zeroes<u16>(x - 1));
+    return 1 << (sizeof(u16) * 8 - count_leading_zeroes_safe<u16>(x - 1));
 }
 
 ErrorOr<NonnullRefPtr<Font>> Font::try_load_from_file(DeprecatedString path, unsigned int index)
diff --git a/Userland/Libraries/LibGfx/Font/WOFF2/Font.cpp b/Userland/Libraries/LibGfx/Font/WOFF2/Font.cpp
index f3f7c2cb62..41d9d93742 100644
--- a/Userland/Libraries/LibGfx/Font/WOFF2/Font.cpp
+++ b/Userland/Libraries/LibGfx/Font/WOFF2/Font.cpp
@@ -113,7 +113,7 @@ static u16 pow_2_less_than_or_equal(u16 x)
 {
     VERIFY(x > 0);
     VERIFY(x < 32769);
-    return 1 << (sizeof(u16) * 8 - count_leading_zeroes<u16>(x - 1));
+    return 1 << (sizeof(u16) * 8 - count_leading_zeroes_safe<u16>(x - 1));
 }
 
 enum class TransformationVersion {