installer: Wipe first bytes of partitions and disks before partitioning.

diff --git a/src/installer/hw.c b/src/installer/hw.c
index 37522649677c55a05c779c4e61b39b2d4f2a4e06..854069f5c7b11673ceab46eee3e22844a155a61d 100644 (file)
--- a/src/installer/hw.c
+++ b/src/installer/hw.c
@@ -505,9 +505,38 @@ unsigned long long hw_memory() {
        return memory * 1024;
 }
 
+static int hw_zero_out_device(const char* path, int bytes) {
+       char block[512];
+       memset(block, 0, sizeof(block));
+
+       int blocks = bytes / sizeof(block);
+
+       int fd = open(path, O_WRONLY);
+       if (fd < 0)
+               return -1;
+
+       unsigned int bytes_written = 0;
+       while (blocks-- > 0) {
+               bytes_written += write(fd, block, sizeof(block));
+       }
+
+       fsync(fd);
+       close(fd);
+
+       return bytes_written;
+}
+
 int hw_create_partitions(struct hw_destination* dest) {
-       char* cmd = NULL;
+       // Before we write a new partition table to the disk, we will erase
+       // the first couple of megabytes at the beginning of the device to
+       // get rid of all left other things like bootloaders and partition tables.
+       // This solves some problems when changing from MBR to GPT partitions or
+       // the other way around.
+       int r = hw_zero_out_device(dest->path, MB2BYTES(10));
+       if (r <= 0)
+               return r;
 
+       char* cmd = NULL;
        asprintf(&cmd, "/usr/sbin/parted -s %s -a optimal", dest->path);
 
        // Set partition type
@@ -798,10 +827,20 @@ int hw_setup_raid(struct hw_destination* dest) {
 
        if (dest->disk1) {
                asprintf(&cmd, "%s %s", cmd, dest->disk1->path);
+
+               // Clear all data at the beginning
+               r = hw_zero_out_device(dest->disk1->path, MB2BYTES(10));
+               if (r <= 0)
+                       return r;
        }
 
        if (dest->disk2) {
                asprintf(&cmd, "%s %s", cmd, dest->disk2->path);
+
+               // Clear all data at the beginning
+               r = hw_zero_out_device(dest->disk2->path, MB2BYTES(10));
+               if (r <= 0)
+                       return r;
        }
 
        int r = mysystem(cmd);