[pve-devel] [PATCH v2 container] fix #3313: recover unprivileged bit from old config during pct restore

[Fabian Ebner]

Works for me and also fixes the "template restore as non-root" issue 
that apparently nobody complained about.

It was a bit confusing to think about $orig_mp_param, whose assignment 
is now also not guarded by $is_root anymore. But if $orig_mp_param is 
used, i.e. if we enter the

     if ($storage_only_mode) {
         if ($restore) {

block, it's set by a second recover_config() call anyways, so that 
should be fine too.

Reviewed-by: Fabian Ebner <f.ebner at proxmox.com>
Tested-by: Fabian Ebner <f.ebner at proxmox.com>

Am 23.02.21 um 13:29 schrieb Oguz Bektas:
> since pct defaults to privileged containers, it restores the container
> as privileged when `--unprivileged 1` is not passed.
> 
> instead we should check the old configuration and retrieve it
> from there.
> 
> this way, when one creates an unprivileged container on GUI, it will be
> still restored as unprivileged via pct (without having to pass
> `--unprivileged 1` parameter)
> 
> Signed-off-by: Oguz Bektas <o.bektas at proxmox.com>
> ---
> v1->v2:
> * move the $is_root guard
> * wrap line to make it shorter
> * shorten comment
> * use () around defined
> * also check defined($orig_conf->{unprivileged})
> 
> 
>   src/PVE/API2/LXC.pm | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/src/PVE/API2/LXC.pm b/src/PVE/API2/LXC.pm
> index 8ce462f..3d3dbb0 100644
> --- a/src/PVE/API2/LXC.pm
> +++ b/src/PVE/API2/LXC.pm
> @@ -352,7 +352,7 @@ __PACKAGE__->register_method({
>   		my $orig_mp_param; # only used if $restore
>   		if ($restore) {
>   		    die "can't overwrite running container\n" if PVE::LXC::check_running($vmid);
> -		    if ($is_root && $archive ne '-') {
> +		    if ($archive ne '-') {
>   			my $orig_conf;
>   			print "recovering backed-up configuration from '$archive'\n";
>   			($orig_conf, $orig_mp_param) = PVE::LXC::Create::recover_config($storage_cfg, $archive, $vmid);
> @@ -361,7 +361,11 @@ __PACKAGE__->register_method({
>   			# causing it to restore the raw lxc entries, among which there may be
>   			# 'lxc.idmap' entries. We need to make sure that the extracted contents
>   			# of the container match up with the restored configuration afterwards:
> -			$conf->{lxc} = $orig_conf->{lxc};
> +			$conf->{lxc} = $orig_conf->{lxc} if $is_root;
> +
> +			# make sure to retrieve the privilege level of container if not specified
> +			$conf->{unprivileged} = $orig_conf->{unprivileged} if !defined($unprivileged)
> +			    && defined($orig_conf->{unprivileged});
>   		    }
>   		}
>   		if ($storage_only_mode) {
>