Re: [pve-devel] [PATCH storage] ZFSPlugin: untaint lun number

[Daniel Berteaud <daniel@firewall-services.com>]

----- Le 9 Oct 20, à 17:13, Stoiko Ivanov s.ivanov@proxmox.com a écrit :

> ZFS over iSCSI fetches information about the disk-images via ssh, thus
> the obtainted data is tainted (perlsec (1)).
> 
> Since pvedaemon runs with '-T' enabled trying to start a VM via GUI/API failed,
> while it still worked via `qm` or `pvesh`.
> 
> The issue surfaced after commit cb9db10c1a9855cf40ff13e81f9dd97d6a9b2698 in
> pve-common ('run_command: improve performance for logging and long lines'),
> and results from concatenating the original (tainted) buffer to a variable,
> instead of a captured subgroup.
> 
> Untainting the value in ZFSPlugin should not cause any regressiosn, since the
> other 3 target providers already have a match on '\d+' for retrieving the
> lun number.
> 
> reported via pve-user [0].
> 
> reproduced and tested by setting up a LIO-target (on top of a virtual PVE),
> adding it as storage and trying to start a guest (with a disk on the
> ZFS over iSCSI storage) with `perl -T /usr/sbin/qm start $vmid`
> 
> [0] https://lists.proxmox.com/pipermail/pve-user/2020-October/172055.html
> 
> Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
> ---
> PVE/Storage/ZFSPlugin.pm | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/PVE/Storage/ZFSPlugin.pm b/PVE/Storage/ZFSPlugin.pm
> index 383f0a0..63b9551 100644
> --- a/PVE/Storage/ZFSPlugin.pm
> +++ b/PVE/Storage/ZFSPlugin.pm
> @@ -159,7 +159,11 @@ sub zfs_get_lun_number {
> 
>     die "could not find lun_number for guid $guid" if !$guid;
> 
> -    return $class->zfs_request($scfg, undef, 'list_view', $guid);
> +    if ($class->zfs_request($scfg, undef, 'list_view', $guid) =~ /^(\d+)$/) {
> +	return $1;
> +    }
> +
> +    die "lun_number for guid $guid is not a number";
> }


Will give this a try ASAP !
Thanks


-- 
[ https://www.firewall-services.com/ ] 	
Daniel Berteaud 
FIREWALL-SERVICES SAS, La sécurité des réseaux 
Société de Services en Logiciels Libres 
Tél : +33.5 56 64 15 32 
Matrix: @dani:fws.fr 
[ https://www.firewall-services.com/ | https://www.firewall-services.com ]