Don't try to spoof 0 length DOS MBR/EBR partitions. By skipping

partitions with 0 in the length field we don't need to test for
and skip partitions that are all zeros. Eliminating that code
allows elimination of a local pointer.

"0 length partitions are definately dead" deraadt@

1 files changed, 6 insertions, 15 deletions

diff --git a/sys/arch/alpha/alpha/disksubr.c b/sys/arch/alpha/alpha/disksubr.c
index ad25008c37f..d15e4613535 100644
--- a/sys/arch/alpha/alpha/disksubr.c
+++ b/sys/arch/alpha/alpha/disksubr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: disksubr.c,v 1.62 2006/10/21 16:01:53 krw Exp $	*/
+/*	$OpenBSD: disksubr.c,v 1.63 2006/10/21 20:10:39 krw Exp $	*/
 /*	$NetBSD: disksubr.c,v 1.21 1996/05/03 19:42:03 christos Exp $	*/
 
 /*
@@ -222,7 +222,7 @@ readdoslabel(bp, strat, lp, osdep, partoffp, cylp, spoofonly)
 	struct partition *pp;
 	unsigned long extoff = 0;
 	daddr_t part_blkno = DOSBBSECTOR;
-	char *msg = NULL, *cp;
+	char *msg = NULL;
 	int dospartoff, cyl, i, ourpart = -1;
 	int wander = 1, n = 0, loop = 0;
 
@@ -307,25 +307,16 @@ donot:
 				continue;
 			if (letoh32(dp2->dp_size) > lp->d_secperunit)
 				continue;
-			if (letoh32(dp2->dp_size))
-				pp->p_size = letoh32(dp2->dp_size);
+			if (letoh32(dp2->dp_size) == 0)
+				continue;
 			if (letoh32(dp2->dp_start))
 				pp->p_offset =
 				    letoh32(dp2->dp_start) + part_blkno;
 
+			pp->p_size = letoh32(dp2->dp_size);
+
 			switch (dp2->dp_typ) {
 			case DOSPTYP_UNUSED:
-				for (cp = (char *)dp2;
-				    cp < (char *)(dp2 + 1); cp++)
-					if (*cp)
-						break;
-				/*
-				 * Was it all zeroes?  If so, it is
-				 * an unused entry that we don't
-				 * want to show.
-				 */
-				if (cp == (char *)(dp2 + 1))
-				    continue;
 				pp->p_fstype = FS_UNUSED;
 				n++;
 				break;