Re: [PATCH V3 0/6] namespaces: log namespaces per task

Richard Guy Briggs
2014-05-26T20:17:41Z

On 14/05/26, Michael Kerrisk (man-pages) wrote:
> Hi Richard
>
> On Mon, May 26, 2014 at 6:58 PM, Richard Guy Briggs <rgb@redhat.com> wrote:
> > On 14/05/22, Michael Kerrisk wrote:
> >> Richard,
> >
> > Hi Michael,
> >
> >> On Tue, May 20, 2014 at 3:12 PM, Richard Guy Briggs <rgb@redhat.com> wrote:
> >> > The purpose is to track namespaces in use by logged processes from the
> >> > perspective of init_*_ns.
> >> >
> >> > 1/6 defines a function to generate them and assigns them.
> >> >
> >> > Use a serial number per namespace (unique across one boot of one kernel)
> >> > instead of the inode number (which is claimed to have had the right to change
> >> > reserved and is not necessarily unique if there is more than one proc fs). It
> >> > could be argued that the inode numbers have now become a defacto interface and
> >> > can't change now, but I'm proposing this approach to see if this helps address
> >> > some of the objections to the earlier patchset.
> >> >
> >> > 2/6 adds access functions to get to the serial numbers in a similar way to
> >> > inode access for namespace proc operations.
> >> >
> >> > 3/6 implements, as suggested by Serge Hallyn, making these serial numbers
> >> > available in /proc/self/ns/{ipc,mnt,net,pid,user,uts}_snum. I chose "snum"
> >> > instead of "seq" for consistency with inum and there are a number of other uses
> >> > of "seq" in the namespace code.
> >> >
> >> > 4/6 exposes proc's ns entries structure which lists a number of useful
> >> > operations per namespace type for other subsystems to use.
> >>
> >> Since the 3 and 4 change the ABI, please CC iterations of this patch
> >> series to linux-api@vger.kernel.org, as per Documentation/SubmitChecklist.
> >
> > Neither patch 3/6 nor 4/6 changes the syscall interface.
>
> (Agreed.)
>
> > Patch 3/6 adds /proc/<pid>/ns/ entries, which looks more like #16 in
> > that document (for which /proc/<pid>/ns/<nstype> was never added).
>
> But, that's a change to the surface that the kernel exposes to user
> space, right? If so, it is best CCed to linux-api.

Got it. Thanks!

> Thanks,
>
> Michael

- RGB

--
Richard Guy Briggs <rbriggs@redhat.com>
Senior Software Engineer, Kernel Security, AMER ENG Base Operating Systems, Red Hat
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