--- 2.4.0-test10/arch/i386/kernel/i387.c.~1~	Thu Nov  2 23:07:22 2000
+++ 2.4.0-test10/arch/i386/kernel/i387.c	Fri Nov  3 22:05:27 2000
@@ -440,9 +440,14 @@
 int set_fpxregs( struct task_struct *tsk, struct user_fxsr_struct *buf )
 {
 	if ( HAVE_FXSR ) {
-		__copy_from_user( &tsk->thread.i387.fxsave, (void *)buf,
-				  sizeof(struct user_fxsr_struct) );
-		return 0;
+		int error;
+
+		error = __copy_from_user(&tsk->thread.i387.fxsave, (void *)buf,
+					 sizeof(struct user_fxsr_struct));
+		/* bit 6 and 31-16 must be zero for security reasons */
+		tsk->thread.i387.fxsave.mxcsr &= 0xffbf;
+
+		return error ? -EFAULT : 0;
 	} else {
 		return -EIO;
 	}