Messages in this thread | | | Date | Wed, 19 Mar 2008 14:11:12 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH 1/1] file capabilities: remove cap_task_kill() (-git) |
| |
On Wed, 19 Mar 2008 11:56:35 -0500 "Serge E. Hallyn" <serue@us.ibm.com> wrote:
> (resending once against -git. I had sent against -stable in > http://lkml.org/lkml/2008/2/28/225. Without this patch, > atd is broken at least on some distros.)
So this fix is needed in 2.6.24.x?
> The original justification for cap_task_kill() was as follows: > > check_kill_permission() does appropriate uid equivalence checks. > However with file capabilities it becomes possible for an > unprivileged user to execute a file with file capabilities > resulting in a more privileged task with the same uid. > > However now that cap_task_kill() always returns 0 (permission > granted) when p->uid==current->uid, the whole hook is worthless, > and only likely to create more subtle problems in the corner cases > where it might still be called but return -EPERM. Those cases > are basically when uids are different but euid/suid is equivalent > as per the check in check_kill_permission(). > > One example of a still-broken application is 'at' for non-root users.
This 2.6.25-rc6 patch doesn't apply correctly to 2.6.24. I can't find a *formal* copy of your 2.6.24 patch on stable@kernel.org, so perhaps a resend for -stable is in order.
| |