[pve-devel] [PATCH qemu-server v2 05/15] api: remove unusable default storage parameter in check_storage_access

[Daniel Kral]

On 2/20/25 15:09, Fiona Ebner wrote:
> Am 11.02.25 um 17:08 schrieb Daniel Kral:
>> Since 0541eeb8 ("use property strings for drive options") the user input
>> of a volume with allocation support must be a pair of a PVE-managed
>> storage and an arbitrary string (i.e. the volume name or the size of a
>> new disk in GB) [0]. Therefore, the `$volid` must always be the string
>> "$storeid:$volname_or_size" for cloudinit images and new disks.
>> Therefore, the `$default_storage` parameter is redundant.
>>
>> Remove it as it is rejected by `verify_volume_id_or_qm_path` for
>> allocatable disk drives before calling this subroutine anyway, which is
>> used by both API handlers, i.e. `create_vm` and `update_vm`, that call
>> the subroutine.
>>
>> [0] except the special cases "none", "cdrom" and absolute paths, which
>>      were introduced some time later with `pve-volume-id-or-absolute-path`
>>      and `pve-volume-id-or-qm-path`.
>>
>> Signed-off-by: Daniel Kral <d.kral at proxmox.com>
>> ---
>> changes since v1:
>> - new!
>>
>>   PVE/API2/Qemu.pm | 11 ++++-------
>>   1 file changed, 4 insertions(+), 7 deletions(-)
>>
>> diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm
>> index 5ac61aa5..2a2d971e 100644
>> --- a/PVE/API2/Qemu.pm
>> +++ b/PVE/API2/Qemu.pm
>> @@ -133,7 +133,7 @@ my $check_drive_param = sub {
>>   };
>>   
>>   my $check_storage_access = sub {
>> -   my ($rpcenv, $authuser, $storecfg, $vmid, $settings, $default_storage, $extraction_storage) = @_;
>> +   my ($rpcenv, $authuser, $storecfg, $vmid, $settings, $extraction_storage) = @_;
>>   
>>      $foreach_volume_with_alloc->($settings, sub {
>>   	my ($ds, $drive) = @_;
>> @@ -143,13 +143,11 @@ my $check_storage_access = sub {
>>   	my $volid = $drive->{file};
>>   	my ($storeid, $volname) = PVE::Storage::parse_volume_id($volid, 1);
>>   
>> -	if (!$volid || ($volid eq 'none' || $volid eq 'cloudinit' || (defined($volname) && $volname eq 'cloudinit'))) {
>> +	if (!$volid || ($volid eq 'none' || (defined($volname) && $volname eq 'cloudinit'))) {
>>   	    # nothing to check
>>   	} elsif ($isCDROM && ($volid eq 'cdrom')) {
>>   	    $rpcenv->check($authuser, "/", ['Sys.Console']);
>>   	} elsif (!$isCDROM && ($volid =~ $PVE::QemuServer::Drive::NEW_DISK_RE)) {
>> -	    my $storeid = $2 || $default_storage;
> 
> The rest looks fine, but I'd rather keep the assignment with the result
> from the regex match here. Because otherwise, the code would rely on
> parse_volume_id() to work for everything matching the regex and that is
> a pretty implicit assumption and might not stay true in the future.

Hm, the reason why I did it this way was so that the following fix for 
cloudinit drives could be written a little bit cleaner as they both need 
the same storage access checks, so I don't need to duplicate the same 
core logic.

I guess I could leave, but I'd have to fallback the `$storeid` provided 
by `parse_volume_id()` for the cloudinit case then, as $2 will not 
contain anything since the NEW_DISK_RE regex was unsuccessful (captures 
only if the $storeid follow a digit). Would that way work for you?

I guess a cleaner way to do this in the future is to make `NEW_DISK_RE` 
depend on the regex of the "pve-volume-id" format as much as possible 
(e.g. the now required $storeid prefix), but that'd be beyond this patch 
series and one should take a closer look before doing this.