Re: Racy manipulation of task_struct->flags in cgroups code causes hard to reproduce kernel panics
From: Peter Zijlstra <hidden>
Date: 2014-09-20 18:04:31
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On Sat, Sep 20, 2014 at 10:15:50AM -0700, Kees Cook wrote:
On Sat, Sep 20, 2014 at 7:30 AM, Peter Zijlstra [off-list ref] wrote:quoted
On Sat, Sep 20, 2014 at 01:55:54PM +0800, Zefan Li wrote:quoted
We should make the updating of this flag atomic.quoted
/* Per-process atomic flags. */ #define PFA_NO_NEW_PRIVS 0x00000001 /* May not gain new privileges. */ +#define PFA_SPREAD_PAGE 0x00000002 /* Spread page cache over cpuset */ +#define PFA_SPREAD_SLAB 0x00000004 /* Spread some slab caches over cpuset */Ooh, I was not ware we had those.. /me checks where that came from. Hmm weird, while I did get that patch it had a seccomp prefix when landing in my inbox so I ignored it. However the commit has a sched prefix (which I would not have ignored). Dubious things happened here.The series went through a lot of revisions, so it probably gained the sched prefix later in its life. Is there anything that needs changing about how this has been implemented?
No, don't think so, just got surprised.