Prevent integer overflow in DL_BLKTOSEC().

ok krw@

diff --git a/sys/sys/disklabel.h b/sys/sys/disklabel.h
index a6fbc91..a26415f 100644 (file)
--- a/sys/sys/disklabel.h
+++ b/sys/sys/disklabel.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: disklabel.h,v 1.42 2008/08/08 23:49:53 krw Exp $      */
+/*     $OpenBSD: disklabel.h,v 1.43 2008/08/09 19:20:07 kettenis Exp $ */
 /*     $NetBSD: disklabel.h,v 1.41 1996/05/10 23:07:37 mark Exp $      */
 
 /*
@@ -229,7 +229,7 @@ struct      __partitionv0 {         /* the partition table */
 
 #define DL_BLKSPERSEC(d)       ((d)->d_secsize / DEV_BSIZE)
 #define DL_SECTOBLK(d, n)      ((n) * DL_BLKSPERSEC(d))
-#define DL_BLKTOSEC(d, n)      (((n) * DEV_BSIZE) / (d)->d_secsize)
+#define DL_BLKTOSEC(d, n)      ((n) / DL_BLKSPERSEC(d))
 #define DL_BLKOFFSET(d, n)     (((n) * DEV_BSIZE) % (d)->d_secsize)
 
 /* d_type values: */