From: miod <miod@openbsd.org>
Date: Fri, 8 Mar 2024 16:18:53 +0000 (+0000)
Subject: Make sure copyoutstr() invoked with a length of zero returns ENAMETOOLONG.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=0ef4c01d20d2bc6284e9fe597e1ab931390ff0fa;p=openbsd

Make sure copyoutstr() invoked with a length of zero returns ENAMETOOLONG.

This bug has been present in that file since the very beginning, more than
28 years ago.
---

diff --git a/sys/arch/m88k/m88k/subr.S b/sys/arch/m88k/m88k/subr.S
index ff73eec1553..b930841170e 100644
--- a/sys/arch/m88k/m88k/subr.S
+++ b/sys/arch/m88k/m88k/subr.S
@@ -1,4 +1,4 @@
-/* $OpenBSD: subr.S,v 1.31 2023/12/12 07:37:21 deraadt Exp $	*/
+/* $OpenBSD: subr.S,v 1.32 2024/03/08 16:18:53 miod Exp $	*/
 /*
  * Mach Operating System
  * Copyright (c) 1993-1992 Carnegie Mellon University
@@ -714,7 +714,7 @@ ENTRY(copyoutstr)
 	or	%r6,  %r6,  %lo16(Lcosflt)
 	st	%r6,  %r7,  PCB_ONFAULT
 	bcnd	lt0,  CNT,  Lcosflt
-	bcnd	eq0,  CNT,  Lcosdone
+	bcnd	eq0,  CNT,  2f
 	or	%r6,  %r0,  0
 1:
 	ld.bu	%r7,  SRC,  %r6
@@ -727,13 +727,14 @@ ENTRY(copyoutstr)
 #else
 	st.b.usr	%r7,  DEST,  %r6
 #endif
-	bcnd.n	eq0,  %r7, 2f		/* all done */
+	bcnd.n	eq0,  %r7, 3f		/* all done */
 	 addu	%r6,  %r6, 1
 	cmp	%r7,  %r6, CNT
 	bb1	lt,   %r7, 1b
+2:
 	br.n	Lcosdone
 	 or	%r2,  %r0, ENAMETOOLONG
-2:
+3:
 	br.n	Lcosdone
 	 or	%r2,  %r0, 0