[libvirt] Mystery of qemu being unable to open NBD Unix domain socket in current directory

[Richard W.M. Jones]

On Thu, Jun 07, 2018 at 01:38:47PM +0200, Peter Krempa wrote:
> On Thu, Jun 07, 2018 at 12:20:16 +0100, Richard W.M. Jones wrote:
> > 
> > I don't know whether or not we decided this was a bug, but
> > I have filed one anyway:
> > 
> > https://bugzilla.redhat.com/show_bug.cgi?id=1588447
> 
> Your XML does not conform to the libvirt domain XML schema which always
> called for an absolute path as we do with all paths in the domain XML:
> 
>         <group>
>           <attribute name="transport">
>             <value>unix</value>
>           </attribute>
>           <attribute name="socket">
>             <ref name="absFilePath"/>
>           </attribute>
>         </group>
> 
> 
> We just did not validate this particular code path in the parser itself
> (when the domain schema validation is not used).

Sure.  Libvirt does need to validate the paths because it's possible
that the *wrong* path will be opened if a relative path is used,
eg. if a socket with the same name happens to exist in "/" (or
whatever is the working directory that libvirt changes to).

Rich.

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