Re: [PATCH] nsproxy cloning error path fix

[Serge E. Hallyn]

Quoting Pavel (xemul@xxxxxxxxxx):
> This patch fixes copy_namespaces()'s error path.
> 
> when new nsproxy (new_ns) is created pointers to namespaces (ipc, uts)
> are copied from the old nsproxy. Later in copy_utsname, copy_ipcs, etc.
> according namespaces are get-ed. On error path needed namespaces are
> put-ed, so there's no need to put new nsproxy itelf as it woud cause
> putting namespaces for the second time.
> 
> Found when incorporating namespaces into OpenVZ kernel.
> 
> Signed-off-by: Pavel Emelianov <xemul@xxxxxxxxxx>

Acked-by: Serge Hallyn <serue@xxxxxxxxxx>

> ---
> 
>  nsproxy.c |    2 +-
>  1 files changed, 1 insertion(+), 1 deletion(-)
> 
> --- ./kernel/nsproxy.c.veboot	2006-08-30 17:48:59.000000000 +0400
> +++ ./kernel/nsproxy.c	2006-08-31 10:54:56.000000000 +0400
> @@ -115,7 +115,7 @@ out_uts:
>  		put_namespace(new_ns->namespace);
>  out_ns:
>  	tsk->nsproxy = old_ns;
> -	put_nsproxy(new_ns);
> +	kfree(new_ns);
>  	goto out;
>  }

Yes, thanks.

The logic has subtly changed since the last version I'd sent out.  I
have tests which should have caught this, and need to start firing off
jobs to periodically test them against -mm.

In fact I notice that it is currently no longer putting old_ns on the
error path.  Seems to me the following patch should be needed on top
of yours.

Meanwhile I'll start firing off a test against v2.6.18-rc4-mm3.

thanks,
-serge