[pve-devel] [PATCH qemu-server 3/3] fix #5563: api: update vm: prohibit changing version of TPM state

[Fiona Ebner]

Sorry, I was too quick to put "fix #5563" here. While it is the issue
from the first comment, there actually is another unrelated issue in the
second comment. So it's best to drop that prefix.

Am 27.06.24 um 13:03 schrieb Fiona Ebner:
> After the TPM state has been created (to be precise, initialized by
> swtpm) it is not possible to change the version anymore. Doing so will
> lead to failure starting the associated VM. While documented in the
> description, it's better to enforce this via API.
> 
> Signed-off-by: Fiona Ebner <f.ebner at proxmox.com>
> ---
>  PVE/API2/Qemu.pm | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm
> index 0c3f451a..74143856 100644
> --- a/PVE/API2/Qemu.pm
> +++ b/PVE/API2/Qemu.pm
> @@ -314,6 +314,24 @@ my $import_from_volid = sub {
>      return $cloned->@{qw(file size)};
>  };
>  
> +my sub prohibit_tpm_version_change {
> +    my ($old, $new) = @_;
> +
> +    return if !$old || !$new;
> +
> +    my $old_drive = PVE::QemuServer::parse_drive('tpmstate0', $old);
> +    my $new_drive = PVE::QemuServer::parse_drive('tpmstate0', $new);
> +
> +    return if $old_drive->{file} ne $new_drive->{file};
> +
> +    my $old_version = $old_drive->{version} // 'v1.2';
> +    my $new_version = $new_drive->{version} // 'v1.2';
> +
> +    die "cannot change TPM state version after creation\n" if $old_version ne $new_version;
> +
> +    return;
> +}
> +
>  # Note: $pool is only needed when creating a VM, because pool permissions
>  # are automatically inherited if VM already exists inside a pool.
>  my sub create_disks : prototype($$$$$$$$$$) {
> @@ -1930,6 +1948,7 @@ my $update_vm_api  = sub {
>  		    # old drive
>  		    if ($conf->{$opt}) {
>  			$check_drive_perms->($opt, $conf->{$opt});
> +			prohibit_tpm_version_change($conf->{$opt}, $param->{$opt}) if $opt eq 'tpmstate0';
>  		    }
>  
>  		    # new drive