From: Karel Zak <kzak@redhat.com>
Date: Mon, 2 Sep 2024 12:04:18 +0000 (+0200)
Subject: sfdisk: ignore last-lba from script on --force
X-Git-Tag: v2.42-start~220
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4877d7f61a72e46aba3fc52f347d1cd74124dba5;p=thirdparty%2Futil-linux.git

sfdisk: ignore last-lba from script on --force

The last LBA depends on the disk size. It seems like a good idea to
ignore it when using the --force option, in order to make it possible
to apply the script on smaller disks.

Addresses: https://github.com/util-linux/util-linux/issues/3186
Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/disk-utils/sfdisk.8.adoc b/disk-utils/sfdisk.8.adoc
index bc3ff9bb8..b2e5279d2 100644
--- a/disk-utils/sfdisk.8.adoc
+++ b/disk-utils/sfdisk.8.adoc
@@ -243,7 +243,7 @@ Specify the partition table identifier. It should be a hexadecimal number (with
 *first-lba*::
 Specify the first usable sector for GPT partitions. This header is ignored if the script and device sector size differ. In this case *sfdisk* uses label specific default.
 *last-lba*::
-Specify the last usable sector for GPT partitions. This header is ignored if the script and device sector size differ. In this case *sfdisk* uses label specific default.
+Specify the last usable sector for GPT partitions. This header is ignored if the script and device sector size differ. In this case *sfdisk* uses label specific default. The last-lba header is ignored if *--force* is specified, making the script usable on disks with different sizes.
 *table-length*::
 Specify the maximal number of GPT partitions.
 *grain*::
diff --git a/disk-utils/sfdisk.c b/disk-utils/sfdisk.c
index 0575373dc..71b0191d2 100644
--- a/disk-utils/sfdisk.c
+++ b/disk-utils/sfdisk.c
@@ -1925,7 +1925,14 @@ static int command_fdisk(struct sfdisk *sf, int argc, char **argv)
 				ignored++;
 				continue;
 			}
-			if (!created) {		/* create a new disklabel */
+			if (!created) {
+				/* ignore "last-lba" and use default if --force specified */
+				if (sf->force && fdisk_script_get_header(dp, "last-lba")) {
+					fdisk_info(sf->cxt, _("Ignoring last-lba script header."));
+					fdisk_script_set_header(dp, "last-lba", NULL);
+				}
+
+				/* create a new disklabel */
 				rc = fdisk_apply_script_headers(sf->cxt, dp);
 				created = !rc;
 				if (rc) {
@@ -1933,7 +1940,6 @@ static int command_fdisk(struct sfdisk *sf, int argc, char **argv)
 					fdisk_warn(sf->cxt, _(
 					  "Failed to apply script headers, disk label not created"));
 				}
-
 				if (rc == 0 && fdisk_get_collision(sf->cxt))
 					follow_wipe_mode(sf);
 			}