From 4f71351796d81b016c1480b8d9ba3e54b67ffab4 Mon Sep 17 00:00:00 2001
From: Vftdan <vftdan@gmail.com>
Date: Sat, 17 Aug 2024 14:47:22 +0200
Subject: [PATCH] Fix ModifierSet buffer overrun

---
 modifiers.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/modifiers.h b/modifiers.h
index 58d7f52..2b9158a 100644
--- a/modifiers.h
+++ b/modifiers.h
@@ -54,6 +54,9 @@ modifier_set_set_from(ModifierSet * target, const ModifierSet source)
 {
 	modifier_set_extend(target, source.byte_length);
 	for (size_t i = 0; i < target->byte_length; ++i) {
+		if (i >= source.byte_length) {
+			return;
+		}
 		target->bits[i] |= source.bits[i];
 	}
 }
@@ -62,6 +65,9 @@ __attribute__((unused)) inline static void
 modifier_set_unset_from(ModifierSet * target, const ModifierSet source)
 {
 	for (size_t i = 0; i < target->byte_length; ++i) {
+		if (i >= source.byte_length) {
+			return;
+		}
 		target->bits[i] &= ~source.bits[i];
 	}
 }
@@ -71,6 +77,9 @@ modifier_set_toggle_from(ModifierSet * target, const ModifierSet source)
 {
 	modifier_set_extend(target, source.byte_length);
 	for (size_t i = 0; i < target->byte_length; ++i) {
+		if (i >= source.byte_length) {
+			return;
+		}
 		target->bits[i] ^= source.bits[i];
 	}
 }