lkml.org 
[lkml]   [2011]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 4/7] allow killing tasks in your own or child userns
    On Mon, Jan 10, 2011 at 09:13:34PM +0000, Serge E. Hallyn wrote:
    > + const struct cred *cred = current_cred();
    > + const struct cred *tcred = __task_cred(t);
    > +
    > + if (cred->user->user_ns != tcred->user->user_ns) {
    > + /* userids are not equivalent - either you have the
    > + capability to the target user ns or you don't */
    > + if (ns_capable(tcred->user->user_ns, CAP_KILL))
    > + return 1;
    > + return 0;
    > + }
    > +
    > + /* same user namespace - usual credentials checks apply */
    > + if ((cred->euid ^ tcred->suid) &&
    > + (cred->euid ^ tcred->uid) &&
    > + (cred->uid ^ tcred->suid) &&
    > + (cred->uid ^ tcred->uid) &&
    > + !ns_capable(tcred->user->user_ns, CAP_KILL))
    > + return 0;
    > +
    > + return 1;

    Isn't that equal to this?

    if (ns_capable(tcred->user->user_ns, CAP_KILL))
    return 1;

    if (cred->user->user_ns == tcred->user->user_ns &&
    (cred->euid == tcred->suid ||
    cred->euid == tcred->uid ||
    cred->uid == tcred->suid ||
    cred->uid == tcred->uid))
    return 1;

    return 0;

    I would consider this much easier to read.

    Bastian

    --
    I'm a soldier, not a diplomat. I can only tell the truth.
    -- Kirk, "Errand of Mercy", stardate 3198.9


    \
     
     \ /
      Last update: 2011-01-10 23:01    [W:0.044 / U:0.164 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site