Hi Herbert

> recent patches (like 0.09.25) use the following code,
> which at least has one bug you mention:
i can`t find this patches at web.

> 
>  ...
>         old_ns = current->namespace;
>         old_fs = current->fs;
>         get_namespace(vxi->vx_namespace);
>         current->namespace = vxi->vx_namespace;
>         current->fs = copy_fs_struct(vxi->vx_fs);
it not need. see fs/open.c:sys_chroot & fs/namespace.c:chroot_fs_refs.

>         put_namespace(old_ns);
>         put_fs_struct(old_fs);
>  ...
but me need lock task before enter to migrate and unlock after.

> 
> 
> > ===
> > second bug. you must adjust 'root' && 'altroot' && pwd and task->fs
> > struct. if not do it - it`s create security hole.
> > How it do see in 
> > namespace.c:chroot_fs_refs and and open.c:sys_chroot.
> 
> do you think the approach above isn't sufficient,
> regarding root and altroot, what security hole
> do you see?
> 
> > i think this references will help you fix code.
> 
With copy_fs_struct is not hole. without have hole.
Please analyze situation when me call this syscall without chroot and
that program been attacked from vps.

-- 
Alex Lyashkov <[EMAIL PROTECTED]>
PSoft
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