Messages in this thread | | | Date | Thu, 9 Dec 2021 15:47:00 +0100 | From | Michal Koutný <> | Subject | Re: [PATCH] exit: Retain nsproxy for exit_task_work() work entries |
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On Thu, Dec 09, 2021 at 03:08:26PM +0100, Christian Brauner <christian.brauner@ubuntu.com> wrote: > send_sig() isn't used that was changed in response to a review. I'm > confused.
Sorry for ambiguity, I meant this instance [1].
> Kill and freeze only do time permission checking at open. Why would you > introduce another write time check?
Let's have a cgroup G with tasks t1,...,tn (run by user u) and some monitoring tasks m1,...,mk belonging to a different user v != u.
Currently u can kill also the tasks of v -- I'm not sure if that's intentional. My argument would apply if it wasn't -- it'd be suscebtible to similar abuse, i.e. passing the opened fd to a more privileged process to kill also v's tasks. (But if the intention is to be able to kill anyone in the cgroup, then it likely doesn't matter.)
Michal
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/kernel/cgroup/cgroup.c?h=v5.16-rc4#n3762
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