diff -Nurp fglrx-installer-8.723.1/lib/modules/fglrx/build_mod/2.6.x/Makefile fglrx-installer-8.723.1.new/lib/modules/fglrx/build_mod/2.6.x/Makefile
--- fglrx-installer-8.723.1/lib/modules/fglrx/build_mod/2.6.x/Makefile	2010-04-09 20:21:39.000000000 +0200
+++ fglrx-installer-8.723.1.new/lib/modules/fglrx/build_mod/2.6.x/Makefile	2010-09-20 14:44:11.026471782 +0200
@@ -67,6 +67,10 @@ EXTRA_CFLAGS    += \
                 -DFGL_LINUX253P1_VMA_API \
                 -DPAGE_ATTR_FIX=$(PAGE_ATTR_FIX) \
 
+ifeq ($(shell grep -q "T compat_alloc_user_space" /proc/kallsyms && echo 1),1)
+	EXTRA_CFLAGS += -DFGL_USE_ARCH_COMPAT_ALLOC_USER_SPACE
+endif
+
 ifeq ($(KERNELRELEASE),)
 # on first call from remote location we get into this path
 # whilst on second call all is managed by the embedding kernel makefile
diff -Nurp fglrx-installer-8.723.1/lib/modules/fglrx/build_mod/kcl_ioctl.c fglrx-installer-8.723.1.new/lib/modules/fglrx/build_mod/kcl_ioctl.c
--- fglrx-installer-8.723.1/lib/modules/fglrx/build_mod/kcl_ioctl.c	2010-04-09 20:21:39.000000000 +0200
+++ fglrx-installer-8.723.1.new/lib/modules/fglrx/build_mod/kcl_ioctl.c	2010-09-20 14:53:32.676471518 +0200
@@ -193,7 +193,22 @@ void ATI_API_CALL KCL_IOCTL_UnregisterCo
  */
 void* ATI_API_CALL KCL_IOCTL_AllocUserSpace32(long size)
 {
-    return compat_alloc_user_space(size);
+    void *ptr;
+
+    /* If len would occupy more than half of the entire compat space... */
+    if (unlikely(((unsigned long) size) > (((compat_uptr_t)~0) >> 1)))
+        return NULL;
+
+#ifdef FGL_USE_ARCH_COMPAT_ALLOC_USER_SPACE
+    ptr = arch_compat_alloc_user_space(size);
+#else
+    ptr = compat_alloc_user_space(size);
+#endif
+
+    if (unlikely(!access_ok(VERIFY_WRITE, ptr, size)))
+        return NULL;
+
+    return ptr;
 }
 
 #endif // __x86_64__