[pve-devel] [PATCH installer 3/6] warn users about existing ESPs on unused disks

[Stoiko Ivanov]

When doing the sanity-checks for the chosen harddisk setup, also check for
existing ESPs on those disks the installer will not touch.

Since they are not touched, the ESP remains on the disk, which can lead to
unbootable systems and other surprises (e.g. when the UEFI implementation
decides to ignore the new bootentry put in front of the list by
`bootctl install` (via `pve-efiboot-tool`) and boots an old system).

If an ESP is detected we warn the user directly at the disk-selection view, and
leave them the option to ignore it or cancel the installation, since wiping
the ESP by clicking an 'OK' button might lead to unexpected data-loss.

ESPs are identified by their partition-type, using `lsblk`'s json output

The message dialog generation is factored in a sub of its own for later reuse.

Signed-off-by: Stoiko Ivanov <s.ivanov at proxmox.com>
---
 debian/control |  2 ++
 proxinstall    | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/debian/control b/debian/control
index 97bf20b..dc1a0f3 100644
--- a/debian/control
+++ b/debian/control
@@ -14,6 +14,7 @@ Package: pve-installer
 Architecture: all
 Depends: geoip-bin,
          libgtk3-webkit2-perl,
+         libjson-perl,
          pve-kernel-helper,
          squashfs-tools,
          ${perl:Depends},
@@ -24,6 +25,7 @@ Package: pmg-installer
 Architecture: all
 Depends: geoip-bin,
          libgtk3-webkit2-perl,
+         libjson-perl,
          pve-kernel-helper,
          squashfs-tools,
          ${perl:Depends},
diff --git a/proxinstall b/proxinstall
index 911ee3d..47faa09 100755
--- a/proxinstall
+++ b/proxinstall
@@ -20,6 +20,7 @@ use Data::Dumper;
 use File::Basename;
 use File::Path;
 use Time::HiRes;
+use JSON;
 
 use ProxmoxInstallerSetup;
 
@@ -3316,6 +3317,7 @@ sub create_hdsel_view {
 
     set_next(undef, sub {
 
+	my $unused = {};
 	if ($config_options->{filesys} =~ m/zfs/) {
 	    my ($devlist) = eval { get_zfs_raid_setup() };
 	    if (my $err = $@) {
@@ -3323,6 +3325,7 @@ sub create_hdsel_view {
 		return;
 	    }
 	    $config_options->{target_hds} = [ map { $_->[1] } @$devlist ];
+	    $unused = get_unused_bdevs($config_options->{target_hds});
 	} elsif ($config_options->{filesys} =~ m/btrfs/) {
 	    my ($devlist) = eval { get_btrfs_raid_setup() };
 	    if (my $err = $@) {
@@ -3330,6 +3333,7 @@ sub create_hdsel_view {
 		return;
 	    }
 	    $config_options->{target_hds} = [ map { $_->[1] } @$devlist ];
+	    $unused = get_unused_bdevs($config_options->{target_hds});
 	} else {
 	    eval { legacy_bios_4k_check(logical_blocksize($target_hd)) };
 	    if (my $err = $@) {
@@ -3337,13 +3341,74 @@ sub create_hdsel_view {
 		return;
 	    }
 	    $config_options->{target_hds} = [ $target_hd ];
+	    $unused = get_unused_bdevs($config_options->{target_hds});
 	}
 
+	warn_existing_esp_ignore_or_abort($unused);
+
 	$step_number++;
 	create_country_view();
     });
 }
 
+sub get_unused_bdevs {
+    my ($used_disks) = @_;
+
+    my @unused_hds;
+    foreach my $hd (@$hds) {
+	my $devname = @$hd[1];
+	if ( ! grep { $devname eq $_ } @$used_disks ){
+	    push @unused_hds, $devname;
+	}
+    }
+
+    my $jsonoutput = '';
+    run_command(['lsblk', '--bytes', '--json',
+        '-o', 'PATH,UUID,FSTYPE,PARTTYPE,LABEL', @unused_hds ], sub {
+            my ($line) = @_;
+            $jsonoutput .= $line;
+        });
+
+    my $lsblk = decode_json($jsonoutput);
+
+    return $lsblk->{blockdevices};
+}
+
+sub warn_existing_esp_ignore_or_abort {
+    my ($unused_devs) = @_;
+
+    return if ($boot_type ne 'efi');
+
+    my @esps = map { $_->{parttype} eq "c12a7328-f81f-11d2-ba4b-00a0c93ec93b" ? ($_->{path}) : () } @$unused_devs;
+    return if !scalar(@esps);
+
+    my $message = "Detected existing ESPs:\n- " . join("\n- ", @esps);
+    $message .= <<'EOF';
+
+
+This could prevent correct booting!
+Do you want to ignore or cancel the installation?
+EOF
+
+    ask_existing_diskconfig_or_abort($message, "existing ESPs");
+}
+
+sub ask_existing_diskconfig_or_abort {
+    my ($message, $fail_reason, $ok_action) = @_;
+
+    my $dialog = Gtk3::MessageDialog->new($window, 'modal', 'question', 'ok-cancel', $message);
+    my $response = $dialog->run();
+    $dialog->destroy();
+
+    if ($response eq 'ok') {
+	$ok_action->() if defined($ok_action);
+    } else {
+	set_next("_Reboot", sub { exit (0); } );
+	display_html("fail.htm");
+	die "Cancled installation by user, due to $fail_reason\n";
+    }
+}
+
 sub create_extract_view {
 
     cleanup_view();
-- 
2.20.1