lkml.org 
[lkml]   [2009]   [Dec]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [RFC][PATCH v3] Unprivileged: Disable raising of privileges
    From
    Date
    "Andrew G. Morgan" <morgan@kernel.org> writes:

    > Why not implement this as another securebit? So far as I can see the
    > whole thing can be implemented in the capability LSM.
    >
    > What is less clear to me is whether per-process 'disabling of setuid
    > bits on files' should force mandatory disabling of file capabilities.
    > It seems as if disabling the transition of one luser to another luser
    > through a setuid executable is something distinct from privilege
    > escalation.
    >
    > Since there is already independent support for disabling file
    > capabilities (the privilege escalation part), I see these two
    > mechanisms as separable.

    The goal is to disable privilege escalation.

    The anatomy of the sendmail capabilities bug as I understand it was:

    - unprivileged process took action to prevent gaining a capability.
    - exec'd suid sendmail.
    - sendmail took action as root because it could not become someone else.

    I would like to trivially stop that entire class of exploit by making
    execing a suid ( or equivalent ) executable impossible.

    Once that hole is closed we can enable things like chroot without
    privilege.

    If there is a way to express this with capabilities today I would be
    more than happy to.

    Eric


    \
     
     \ /
      Last update: 2009-12-31 19:35    [W:0.032 / U:0.472 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site