From 4ff404cc2d7ab74d0b1000c0212318dcbb2dda11 Mon Sep 17 00:00:00 2001
From: Petr Uzel <petr.uzel@suse.cz>
Date: Thu, 28 Apr 2016 17:18:44 +0200
Subject: [PATCH] parted: implement --wipesignatures option

With this option, parted uses libblkid to wipe superblock signatures
from a disk region where it is about to create a new partition.

References: bsc#943623
References: fate#319893
---
 doc/C/parted.8  |    4 +++
 parted/parted.c |   70 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+)

Index: parted-3.2/doc/C/parted.8
===================================================================
--- parted-3.2.orig/doc/C/parted.8
+++ parted-3.2/doc/C/parted.8
@@ -30,6 +30,10 @@ never prompts for user intervention
 .B -v, --version
 displays the version
 .TP
+.B --wipesignatures
+mkpart wipes the superblock signatures from the disk region where it is
+about to create the partition
+.TP
 .B -a \fIalignment-type\fP, --align \fIalignment-type\fP
 Set alignment for newly created partitions, valid alignment types are:
 .RS
Index: parted-3.2/parted/parted.c
===================================================================
--- parted-3.2.orig/parted/parted.c
+++ parted-3.2/parted/parted.c
@@ -57,6 +57,11 @@
 #include "c-strcase.h"
 #include "xalloc.h"
 
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <blkid/blkid.h>
+
 #ifdef ENABLE_MTRACE
 #include <mcheck.h>
 #endif
@@ -76,6 +81,7 @@ static int MEGABYTE_SECTORS (PedDevice*
 enum
 {
   PRETEND_INPUT_TTY = CHAR_MAX + 1,
+  WIPESIGNATURES = CHAR_MAX + 2,
 };
 
 enum
@@ -117,6 +123,7 @@ static struct option const options[] = {
         {"script",      0, NULL, 's'},
         {"version",     0, NULL, 'v'},
         {"align",       required_argument, NULL, 'a'},
+        {"wipesignatures", 0, NULL, WIPESIGNATURES},
         {"-pretend-input-tty", 0, NULL, PRETEND_INPUT_TTY},
         {NULL,          0, NULL, 0}
 };
@@ -128,11 +135,13 @@ static const char *const options_help []
         {"script",      N_("never prompts for user intervention")},
         {"version",     N_("displays the version")},
         {"align=[none|cyl|min|opt]", N_("alignment for new partitions")},
+        {"wipesignatures", N_("wipe superblock signatures when creating partition")},
         {NULL,          NULL}
 };
 
 int     opt_script_mode = 0;
 int     pretend_input_tty = 0;
+int     wipesignatures = 0;
 int     opt_machine_mode = 0;
 int     disk_is_modified = 0;
 int     is_toggle_mode = 0;
@@ -650,6 +659,56 @@ _adjust_end_if_iec (PedSector* start, Pe
         }
 }
 
+#ifdef USE_BLKID
+static int
+_wipe_signatures (PedDevice *dev, PedSector start, PedSector length)
+{
+	int fd = open (dev->path, O_RDWR);
+	if (fd == -1)
+		goto error;
+
+	blkid_loff_t wipe_offset = start * dev->sector_size;
+	blkid_loff_t wipe_size = length * dev->sector_size;
+
+	blkid_probe pr;
+	pr = blkid_new_probe();
+	if (!pr)
+		goto error_close_fd;
+
+	if (blkid_probe_set_device(pr, fd, wipe_offset, wipe_size) == -1)
+		goto error_free_probe;
+	if (blkid_probe_enable_superblocks(pr, 1) == -1)
+		goto error_free_probe;
+	if (blkid_probe_set_superblocks_flags(pr, BLKID_SUBLKS_MAGIC) == -1)
+		goto error_free_probe;
+
+	while (blkid_do_probe(pr) == 0) {
+		if (blkid_do_wipe(pr, 0) == -1)
+			goto error_free_probe;
+	}
+
+	blkid_free_probe(pr);
+	close(fd);
+	return 1;
+
+error_free_probe:
+	blkid_free_probe(pr);
+
+error_close_fd:
+	close(fd);
+
+error:
+	return 0;
+
+}
+#else
+static int
+_wipe_signatures (PedDevice *dev, PedSector start, PedSector length)
+{
+	return 0;
+}
+#endif
+
 static int
 do_mkpart (PedDevice** dev, PedDisk** diskp)
 {
@@ -840,6 +899,14 @@ do_mkpart (PedDevice** dev, PedDisk** di
         if (ped_partition_is_flag_available (part, PED_PARTITION_LBA))
                 ped_partition_set_flag (part, PED_PARTITION_LBA, 1);
 
+	if (wipesignatures) {
+		if (!_wipe_signatures(*dev, part->geom.start, part->geom.length))
+			ped_exception_throw (
+				PED_EXCEPTION_WARNING,
+				PED_EXCEPTION_OK,
+				_("Wiping the superblock signatures has failed."));
+	}
+
         if (!ped_disk_commit (disk))
                 goto error;
 
@@ -2196,6 +2263,9 @@ while (1)
                 case PRETEND_INPUT_TTY:
                   pretend_input_tty = 1;
                   break;
+                case WIPESIGNATURES:
+                  wipesignatures = 1;
+                  break;
                 default:
                   wrong = 1;
                   break;