[libvirt] [PATCH v2 1/2] nwfilter: Disallow binding creation in session mode

[Daniel P. Berrangé]

On Thu, Aug 30, 2018 at 12:50:09PM -0400, John Ferlan wrote:
> 
> 
> On 08/30/2018 12:27 PM, Daniel P. Berrangé wrote:
> > On Thu, Aug 30, 2018 at 11:06:07AM -0400, John Ferlan wrote:
> >> Similar to nwfilterDefineXML, let's be sure the a filter binding
> >> creation is not attempted in session mode and generate the proper
> >> error message.
> >>
> >> Failure to open nwfilter in session mode (nwfilterConnectOpen)
> >> fails already, but that doesn't stop the free thinker from using
> >> a different connection in order to attempt to attempt to create
> >> the binding. Although even doing that would result in a failure:
> >>
> >> $ virsh nwfilter-binding-create QEMUGuest1-binding.xml
> >> error: Failed to create network filter from QEMUGuest1-binding.xml
> >> error: internal error: Could not get access to ACL tech driver 'ebiptables'
> >>
> >> $
> >>
> >> Signed-off-by: John Ferlan <jferlan at redhat.com>
> >> ---
> >>  src/nwfilter/nwfilter_driver.c | 6 ++++++
> >>  1 file changed, 6 insertions(+)
> >>
> >> diff --git a/src/nwfilter/nwfilter_driver.c b/src/nwfilter/nwfilter_driver.c
> >> index ac3a964388..1ee5162b9a 100644
> >> --- a/src/nwfilter/nwfilter_driver.c
> >> +++ b/src/nwfilter/nwfilter_driver.c
> >> @@ -745,6 +745,12 @@ nwfilterBindingCreateXML(virConnectPtr conn,
> >>  
> >>      virCheckFlags(0, NULL);
> >>  
> >> +    if (!driver->privileged) {
> >> +        virReportError(VIR_ERR_OPERATION_INVALID, "%s",
> >> +                       _("Can't define NWFilter bindings in session mode"));
> >> +        return NULL;
> >> +    }
> >> +
> >>      def = virNWFilterBindingDefParseString(xml);
> >>      if (!def)
> >>          return NULL;
> > 
> > How do we ever get to this point in a session daemon ?
> 
> Like I noted in the commit message an enterprising user...
> 
> With no guest running:
> 
> $ virsh -c qemu:///session nwfilter-binding-create QEMUGuest1-binding.xml
> Network filter binding on tap0 created from QEMUGuest1-binding.xml

Oh, i see it is because when using qemu://session, we never
actually call the nwfilterConnectOpen method - it is opened
implicitly. So

Reviewed-by: Daniel P. Berrangé <berrange at redhat.com>


Regards,
Daniel
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