diff --git a/AK/ByteBuffer.h b/AK/ByteBuffer.h
index d11e157610..5f19d2b299 100644
--- a/AK/ByteBuffer.h
+++ b/AK/ByteBuffer.h
@@ -41,7 +41,7 @@ public:
     {
         if (this != &other) {
             if (!m_inline)
-                kfree(m_outline_buffer);
+                kfree_sized(m_outline_buffer, m_outline_capacity);
             move_from(move(other));
         }
         return *this;
@@ -138,7 +138,7 @@ public:
     void clear()
     {
         if (!m_inline) {
-            kfree(m_outline_buffer);
+            kfree_sized(m_outline_buffer, m_outline_capacity);
             m_inline = true;
         }
         m_size = 0;
@@ -230,9 +230,10 @@ private:
     {
         // m_inline_buffer and m_outline_buffer are part of a union, so save the pointer
         auto outline_buffer = m_outline_buffer;
+        auto outline_capacity = m_outline_capacity;
         if (!may_discard_existing_data)
             __builtin_memcpy(m_inline_buffer, outline_buffer, size);
-        kfree(outline_buffer);
+        kfree_sized(outline_buffer, outline_capacity);
         m_inline = true;
     }