From 51413dc1528c5ef2a0199fcedd276c6542954b92 Mon Sep 17 00:00:00 2001
From: Philip Guenther <guenther@cvs.openbsd.org>
Date: Thu, 11 Apr 2013 00:44:27 +0000
Subject: The tweaks I suggested to the previous diff resulted in the typeflag
 being checked after it was overwritten by the next block read in. Eliminate
 the argument aliasing that led to this being overlooked by passing
 rd_xheader() the size and typeflag directly.

problem discovery and ok fgsch@
---
 bin/pax/tar.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

(limited to 'bin')

diff --git a/bin/pax/tar.c b/bin/pax/tar.c
index ec4c809b6ba..0823825bf4b 100644
--- a/bin/pax/tar.c
+++ b/bin/pax/tar.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tar.c,v 1.46 2013/04/09 18:30:34 fgsch Exp $	*/
+/*	$OpenBSD: tar.c,v 1.47 2013/04/11 00:44:26 guenther Exp $	*/
 /*	$NetBSD: tar.c,v 1.5 1995/03/21 09:07:49 cgd Exp $	*/
 
 /*-
@@ -60,7 +60,7 @@ static int ul_oct(u_long, char *, int, int);
 static int uqd_oct(u_quad_t, char *, int, int);
 #endif
 #ifndef SMALL
-static int rd_xheader(ARCHD *, char *, HD_USTAR **);
+static int rd_xheader(ARCHD *, char *, off_t, char);
 #endif
 
 static uid_t uid_nobody;
@@ -760,7 +760,9 @@ ustar_rd(ARCHD *arcn, char *buf)
 #ifndef SMALL
 	/* Process the Extended header. */
 	if (hd->typeflag == XHDRTYPE || hd->typeflag == GHDRTYPE) {
-		if (rd_xheader(arcn, buf, &hd) < 0)
+		if (rd_xheader(arcn, buf,
+		    (off_t)asc_ul(hd->size, sizeof(hd->size), OCT),
+		    hd->typeflag) < 0)
 			return (-1);
 	}
 #endif
@@ -1204,13 +1206,12 @@ expandname(char *buf, size_t len, char **gnu_name, const char *name,
 #define MINXHDRSZ	6
 
 static int
-rd_xheader(ARCHD *arcn, char *buf, HD_USTAR **hd)
+rd_xheader(ARCHD *arcn, char *buf, off_t size, char typeflag)
 {
-	off_t len, size;
+	off_t len;
 	char *delim, *keyword;
 	char *nextp, *p;
 
-	size = (off_t)asc_ul((*hd)->size, sizeof((*hd)->size), OCT);
 	if (size < MINXHDRSZ) {
 		paxwarn(1, "Invalid extended header length");
 		return (-1);
@@ -1246,7 +1247,7 @@ rd_xheader(ARCHD *arcn, char *buf, HD_USTAR **hd)
 			return (-1);
 		}
 		*p++ = nextp[-1] = '\0';
-		if ((*hd)->typeflag == XHDRTYPE) {
+		if (typeflag == XHDRTYPE) {
 			if (!strcmp(keyword, "path")) {
 				arcn->nlen = strlcpy(arcn->name, p,
 				    sizeof(arcn->name));
@@ -1260,7 +1261,6 @@ rd_xheader(ARCHD *arcn, char *buf, HD_USTAR **hd)
 	/* Update the ustar header. */
 	if (rd_wrbuf(buf, BLKMULT) != BLKMULT)
 		return (-1);
-	*hd = (HD_USTAR *)buf;
 	return (0);
 }
 #endif
-- 
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