3 files changed, 11 insertions, 0 deletions
diff --git a/perl-install/NEWS b/perl-install/NEWS
index 044bc22ab..553d1d463 100644
--- a/perl-install/NEWS
+++ b/perl-install/NEWS
@@ -1,5 +1,6 @@
 - diskdrake:
   o fix adding parts to extended partition on hybrid ISO (mga#27862)
+  o erase iso9660 signature when clearing hybrid ISO disk (mga#27864)
 - drakbug_report:
   o also try journalctl for system log
   o include draklive-install.log
diff --git a/perl-install/install/NEWS b/perl-install/install/NEWS
index 1af0987b2..b88e624d5 100644
--- a/perl-install/install/NEWS
+++ b/perl-install/install/NEWS
@@ -1,3 +1,5 @@
+- partitioning:
+  o erase iso9660 signature when clearing hybrid ISO disk (mga#27864)
 - support https in media URL (mga#27776)
 
 Version 18.37 - 5 December 2020
diff --git a/perl-install/partition_table/dos.pm b/perl-install/partition_table/dos.pm
index 3bcb226c4..aa020131a 100644
--- a/perl-install/partition_table/dos.pm
+++ b/perl-install/partition_table/dos.pm
@@ -272,6 +272,12 @@ sub start_write {
 	open $F, ">$file" or die "error opening test file $file";
     } else {
 	$F = partition_table::raw::openit($hd, 2) or die "error opening device $hd->{device} for writing";
+	if ($hd->{was_hybrid_iso}) {
+	    log::l("partition::dos::start_write erasing hybrid iso9660 signature");
+	    c::lseek_sector(fileno($F), 0, 0x8001) or return 0;
+	    syswrite $F, "\0\0\0\0\0", 5 or return 0;
+	    $hd->{was_hybrid_iso} = 0;
+	}
     }
     $F;
 }
@@ -344,6 +350,8 @@ sub initialize {
     my ($class, $hd) = @_;
     # Remember whether any existing partitions are mounted, for use by need_to_tell_kernel().
     $hd->{hadMountedPartitions} = 1 if any { $_->{isMounted} } partition_table::get_normal_parts($hd);
+    # Remember whether this was a hybrid ISO so we can wipe the iso9660 signature.
+    $hd->{was_hybrid_iso} = 1 if $hd->{primary}{is_hybrid_iso};
     $hd->{primary} = empty_raw();
     bless $hd, $class;
 }