fix extended partition support by handling chained EBRs correctly

(using a recursion limit).  now OpenBSD can be installed in a
subsequent DOS/Linux-compatible extended partition.

ok krw@ deraadt@

5 files changed, 45 insertions, 53 deletions

diff --git a/sbin/disklabel/disklabel.c b/sbin/disklabel/disklabel.c
index 7c287a3cbcb..abc88b92731 100644
--- a/sbin/disklabel/disklabel.c
+++ b/sbin/disklabel/disklabel.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: disklabel.c,v 1.133 2008/07/10 00:21:39 krw Exp $	*/
+/*	$OpenBSD: disklabel.c,v 1.134 2008/08/04 15:58:13 reyk Exp $	*/
 
 /*
  * Copyright (c) 1987, 1993
@@ -39,7 +39,7 @@ static const char copyright[] =
 #endif /* not lint */
 
 #ifndef lint
-static const char rcsid[] = "$OpenBSD: disklabel.c,v 1.133 2008/07/10 00:21:39 krw Exp $";
+static const char rcsid[] = "$OpenBSD: disklabel.c,v 1.134 2008/08/04 15:58:13 reyk Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -579,19 +579,19 @@ findopenbsd(int f, off_t mbroff, struct dos_partition **first, int *n)
 			    "type %02X start %u size %u\n",
 			    part, dp[part].dp_typ,
 			    letoh32(dp[part].dp_start), letoh32(dp[part].dp_size));
+			dp[part].dp_start =
+			    htole32((off_t)letoh32(dp[part].dp_start) + mbroff);
 			return (&dp[part]);
+		case DOSPTYP_EXTEND:
 		case DOSPTYP_EXTENDL:
 			fprintf(stderr, "# Extended partition %d: "
 			    "type %02X start %u size %u\n",
 			    part, dp[part].dp_typ,
 			    letoh32(dp[part].dp_start), letoh32(dp[part].dp_size));
-			start = letoh32(dp[part].dp_start);
+			start = letoh32(dp[part].dp_start) + mbroff;
 			p = findopenbsd(f, start, NULL, n);
-			if (p != NULL) {
-				p->dp_start =
-				    htole32(letoh32(p->dp_start) + start);
+			if (p != NULL)
 				return (p);
-			}
 			break;
 		}
 	}
diff --git a/sys/arch/amd64/stand/installboot/installboot.c b/sys/arch/amd64/stand/installboot/installboot.c
index 88f134a0094..fb0e95ffce0 100644
--- a/sys/arch/amd64/stand/installboot/installboot.c
+++ b/sys/arch/amd64/stand/installboot/installboot.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: installboot.c,v 1.9 2008/06/25 15:26:44 reyk Exp $	*/
+/*	$OpenBSD: installboot.c,v 1.10 2008/08/04 15:58:13 reyk Exp $	*/
 /*	$NetBSD: installboot.c,v 1.5 1995/11/17 23:23:50 gwr Exp $ */
 
 /*
@@ -231,7 +231,7 @@ findopenbsd(int devfd, struct disklabel *dl, off_t mbroff, int *n)
 	if (!(*n)--)
 		return (-1);
 
-	if (lseek(devfd, mbroff, SEEK_SET) < 0 ||
+	if (lseek(devfd, mbroff * dl->d_secsize, SEEK_SET) < 0 ||
 	    read(devfd, &mbr, sizeof(mbr)) != sizeof(mbr))
 		err(4, "can't read master boot record");
 
@@ -242,14 +242,13 @@ findopenbsd(int devfd, struct disklabel *dl, off_t mbroff, int *n)
 	    dp++) {
 		if (!dp->dp_size)
 			continue;
-		startoff = (off_t)dp->dp_start * dl->d_secsize;
 		if (dp->dp_typ == DOSPTYP_OPENBSD) {
 			fprintf(stderr, "using MBR partition %ld: "
 			    "type %d (0x%02x) offset %d (0x%x)\n",
 			    (long)(dp - mbr.dmbr_parts),
 			    dp->dp_typ, dp->dp_typ,
 			    dp->dp_start, dp->dp_start);
-			break;
+			return (dp->dp_start + mbroff);
 		} else if (dp->dp_typ == DOSPTYP_EXTEND ||
 		    dp->dp_typ == DOSPTYP_EXTENDL) {
 			fprintf(stderr, "extended partition %ld: "
@@ -257,16 +256,14 @@ findopenbsd(int devfd, struct disklabel *dl, off_t mbroff, int *n)
 			    (long)(dp - mbr.dmbr_parts),
 			    dp->dp_typ, dp->dp_typ,
 			    dp->dp_start, dp->dp_start);
+			startoff = (off_t)dp->dp_start + mbroff;
 			start = findopenbsd(devfd, dl, startoff, n);
 			if (start != -1)
-				return (dp->dp_start + start);
+				return (start);
 		}
 	}
-	/* Don't check for old part number, that is ;-p */
-	if (dp >= &mbr.dmbr_parts[NDOSPART])
-		return (-1);
 
-	return (dp->dp_start);
+	return (-1);
 }
 
 /*
diff --git a/sys/arch/amd64/stand/libsa/biosdev.c b/sys/arch/amd64/stand/libsa/biosdev.c
index 7358eab09f6..ad5075e324f 100644
--- a/sys/arch/amd64/stand/libsa/biosdev.c
+++ b/sys/arch/amd64/stand/libsa/biosdev.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: biosdev.c,v 1.6 2008/06/25 15:32:18 reyk Exp $	*/
+/*	$OpenBSD: biosdev.c,v 1.7 2008/08/04 15:58:13 reyk Exp $	*/
 
 /*
  * Copyright (c) 1996 Michael Shalayeff
@@ -45,8 +45,7 @@ static int biosdisk_errno(u_int);
 static int CHS_rw (int, int, int, int, int, int, void *);
 static int EDD_rw (int, int, u_int64_t, u_int32_t, void *);
 
-static daddr_t findopenbsd(bios_diskinfo_t *, daddr_t, daddr_t *,
-    const char **, int *);
+static daddr_t findopenbsd(bios_diskinfo_t *, daddr_t, const char **, int *);
 
 extern int debug;
 int bios_bootdev;
@@ -343,8 +342,7 @@ biosd_io(int rw, bios_diskinfo_t *bd, daddr_t off, int nsect, void *buf)
  * Try to read the bsd label on the given BIOS device
  */
 static daddr_t
-findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
-    int *n)
+findopenbsd(bios_diskinfo_t *bd, daddr_t off, const char **err, int *n)
 {
 	int error, i;
 	struct dos_mbr mbr;
@@ -370,7 +368,7 @@ findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
 	}
 
 	/* Search for OpenBSD partition */
-	for (off = 0, i = 0; off == 0 && i < NDOSPART; i++) {
+	for (i = 0; i < NDOSPART; i++) {
 		dp = &mbr.dmbr_parts[i];
 #ifdef BIOS_DEBUG
 		if (debug)
@@ -380,13 +378,14 @@ findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
 			    dp->dp_typ, dp->dp_typ,
 			    dp->dp_start, dp->dp_start);
 #endif
-		if (dp->dp_typ == DOSPTYP_OPENBSD)
-			off = dp->dp_start;
-		else if (dp->dp_typ == DOSPTYP_EXTEND ||
+		if (dp->dp_typ == DOSPTYP_OPENBSD) {
+			off = dp->dp_start + off;
+			break;
+		} else if (dp->dp_typ == DOSPTYP_EXTEND ||
 		    dp->dp_typ == DOSPTYP_EXTENDL) {
-			off = findopenbsd(bd, dp->dp_start, roff, err, n);
+			off = findopenbsd(bd, dp->dp_start + off, err, n);
 			if (off != 0)
-				*roff = dp->dp_start;
+				break;
 		}
 	}
 
@@ -407,7 +406,7 @@ findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
 const char *
 bios_getdisklabel(bios_diskinfo_t *bd, struct disklabel *label)
 {
-	daddr_t off = 0, roff = 0;
+	daddr_t off = 0;
 	char *buf;
 	const char *err = NULL;
 	int error;
@@ -420,14 +419,14 @@ bios_getdisklabel(bios_diskinfo_t *bd, struct disklabel *label)
 
 	/* MBR is a harddisk thing */
 	if (bd->bios_number & 0x80) {
-		off = findopenbsd(bd, DOSBBSECTOR, &roff, &err, &n);
+		off = findopenbsd(bd, DOSBBSECTOR, &err, &n);
 		if (off == 0) {
 			if (err != NULL)
 				return (err);
  			return "no OpenBSD partition\n";
 		}
 	}
-	off = LABELSECTOR + off + roff;
+	off = LABELSECTOR + off;
 
 	/* Load BSD disklabel */
 	buf = alloca(DEV_BSIZE);
diff --git a/sys/arch/i386/stand/installboot/installboot.c b/sys/arch/i386/stand/installboot/installboot.c
index d0a450147a1..1658d05c0a2 100644
--- a/sys/arch/i386/stand/installboot/installboot.c
+++ b/sys/arch/i386/stand/installboot/installboot.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: installboot.c,v 1.52 2008/06/25 15:26:44 reyk Exp $	*/
+/*	$OpenBSD: installboot.c,v 1.53 2008/08/04 15:58:13 reyk Exp $	*/
 /*	$NetBSD: installboot.c,v 1.5 1995/11/17 23:23:50 gwr Exp $ */
 
 /*
@@ -227,7 +227,7 @@ findopenbsd(int devfd, struct disklabel *dl, off_t mbroff, int *n)
 	if (!(*n)--)
 		return (-1);
 
-	if (lseek(devfd, mbroff, SEEK_SET) < 0 ||
+	if (lseek(devfd, mbroff * dl->d_secsize, SEEK_SET) < 0 ||
 	    read(devfd, &mbr, sizeof(mbr)) != sizeof(mbr))
 		err(4, "can't read master boot record");
 
@@ -238,14 +238,13 @@ findopenbsd(int devfd, struct disklabel *dl, off_t mbroff, int *n)
 	    dp++) {
 		if (!dp->dp_size)
 			continue;
-		startoff = (off_t)dp->dp_start * dl->d_secsize;
 		if (dp->dp_typ == DOSPTYP_OPENBSD) {
 			fprintf(stderr, "using MBR partition %ld: "
 			    "type %d (0x%02x) offset %d (0x%x)\n",
 			    (long)(dp - mbr.dmbr_parts),
 			    dp->dp_typ, dp->dp_typ,
 			    dp->dp_start, dp->dp_start);
-			break;
+			return (dp->dp_start + mbroff);
 		} else if (dp->dp_typ == DOSPTYP_EXTEND ||
 		    dp->dp_typ == DOSPTYP_EXTENDL) {
 			fprintf(stderr, "extended partition %ld: "
@@ -253,16 +252,14 @@ findopenbsd(int devfd, struct disklabel *dl, off_t mbroff, int *n)
 			    (long)(dp - mbr.dmbr_parts),
 			    dp->dp_typ, dp->dp_typ,
 			    dp->dp_start, dp->dp_start);
+			startoff = (off_t)dp->dp_start + mbroff;
 			start = findopenbsd(devfd, dl, startoff, n);
 			if (start != -1)
-				return (dp->dp_start + start);
+				return (start);
 		}
 	}
-	/* Don't check for old part number, that is ;-p */
-	if (dp >= &mbr.dmbr_parts[NDOSPART])
-		return (-1);
 
-	return (dp->dp_start);
+	return (-1);
 }
 
 /*
diff --git a/sys/arch/i386/stand/libsa/biosdev.c b/sys/arch/i386/stand/libsa/biosdev.c
index 2b8220225ac..3ccc01258cd 100644
--- a/sys/arch/i386/stand/libsa/biosdev.c
+++ b/sys/arch/i386/stand/libsa/biosdev.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: biosdev.c,v 1.74 2008/06/25 15:32:18 reyk Exp $	*/
+/*	$OpenBSD: biosdev.c,v 1.75 2008/08/04 15:58:13 reyk Exp $	*/
 
 /*
  * Copyright (c) 1996 Michael Shalayeff
@@ -46,8 +46,7 @@ static int biosdisk_errno(u_int);
 static int CHS_rw (int, int, int, int, int, int, void *);
 static int EDD_rw (int, int, u_int64_t, u_int32_t, void *);
 
-static daddr_t findopenbsd(bios_diskinfo_t *, daddr_t, daddr_t *,
-    const char **, int *);
+static daddr_t findopenbsd(bios_diskinfo_t *, daddr_t, const char **, int *);
 
 extern int debug;
 int bios_bootdev;
@@ -346,8 +345,7 @@ biosd_io(int rw, bios_diskinfo_t *bd, daddr_t off, int nsect, void *buf)
  * Try to read the bsd label on the given BIOS device
  */
 static daddr_t
-findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
-    int *n)
+findopenbsd(bios_diskinfo_t *bd, daddr_t off, const char **err, int *n)
 {
 	int error, i;
 	struct dos_mbr mbr;
@@ -373,7 +371,7 @@ findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
 	}
 
 	/* Search for OpenBSD partition */
-	for (off = 0, i = 0; off == 0 && i < NDOSPART; i++) {
+	for (i = 0; i < NDOSPART; i++) {
 		dp = &mbr.dmbr_parts[i];
 #ifdef BIOS_DEBUG
 		if (debug)
@@ -383,13 +381,14 @@ findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
 			    dp->dp_typ, dp->dp_typ,
 			    dp->dp_start, dp->dp_start);
 #endif
-		if (dp->dp_typ == DOSPTYP_OPENBSD)
-			off = dp->dp_start;
-		else if (dp->dp_typ == DOSPTYP_EXTEND ||
+		if (dp->dp_typ == DOSPTYP_OPENBSD) {
+			off = dp->dp_start + off;
+			break;
+		} else if (dp->dp_typ == DOSPTYP_EXTEND ||
 		    dp->dp_typ == DOSPTYP_EXTENDL) {
-			off = findopenbsd(bd, dp->dp_start, roff, err, n);
+			off = findopenbsd(bd, dp->dp_start + off, err, n);
 			if (off != 0)
-				*roff = dp->dp_start;
+				break;
 		}
 	}
 
@@ -410,7 +409,7 @@ findopenbsd(bios_diskinfo_t *bd, daddr_t off, daddr_t *roff, const char **err,
 const char *
 bios_getdisklabel(bios_diskinfo_t *bd, struct disklabel *label)
 {
-	daddr_t off = 0, roff = 0;
+	daddr_t off = 0;
 	char *buf;
 	const char *err = NULL;
 	int error;
@@ -423,14 +422,14 @@ bios_getdisklabel(bios_diskinfo_t *bd, struct disklabel *label)
 
 	/* MBR is a harddisk thing */
 	if (bd->bios_number & 0x80) {
-		off = findopenbsd(bd, DOSBBSECTOR, &roff, &err, &n);
+		off = findopenbsd(bd, DOSBBSECTOR, &err, &n);
 		if (off == 0) {
 			if (err != NULL)
 				return (err);
  			return "no OpenBSD partition\n";
 		}
 	}
-	off = LABELSECTOR + off + roff;
+	off = LABELSECTOR + off;
 
 	/* Load BSD disklabel */
 	buf = alloca(DEV_BSIZE);