Quoting C Anthony Risinger (anthony@xxxxxxx): > On Mon, May 23, 2011 at 4:05 PM, Eric W. Biederman > <ebiederm@xxxxxxxxxxxx> wrote: > > > > This tree adds the files /proc/<pid>/ns/net, /proc/<pid>/ns/ipc, > > /proc/<pid>/ns/uts that can be opened to refer to the namespaces of a > > process at the time those files are opened, and can be bind mounted to > > keep the specified namespace alive without a process. > > > > This tree adds the setns system call that can be used to change the > > specified namespace of a process to the namespace specified by a system > > call. > > i just have a quick question regarding these, apologies if wrong place > to respond -- i trimmed to lists only. > > if i understand correctly, mount namespaces (for example), allow one > to build such constructs as "private /tmp" and similar that even > `root` cannot access ... and there are many reasons `root` does not > deserve to completely know/interact with user processes (FUSE makes a > good example ... just because i [user] have SSH access to a machine, > why should `root`?) > > would these /proc additions break such guarantees? IOW, would it now > become possible for `root` to inject stuff into my private namespaces, > and/or has these guarantees never existed and i am mistaken? is there > any kind of ACL mechanism that endows the origin process (or similar) > with the ability to dictate who can hold and/or interact with these > references? If for instance you have a file open in your private /tmp, then root in another mounts ns can open the file through /proc/$$/fd/N anyway. If it's a directory, he can now traverse the whole fs. -serge _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
