From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [RFC] [PATCH -mm] oom_kill: remove uid==0 checks Date: Thu, 20 Dec 2007 16:34:42 -0800 Message-ID: <20071220163442.d93210ea.akpm@linux-foundation.org> References: <20071212211835.GA24943@sergelap.austin.ibm.com> <47606969.6060808@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <47606969.6060808-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Andrew Morgan Cc: containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, minslinux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org List-Id: containers.vger.kernel.org On Wed, 12 Dec 2007 15:06:17 -0800 Andrew Morgan wrote: > Serge E. Hallyn wrote: > > Andrew, I've cc:d you here bc in doing this patch I noticed that your > > 64-bit capabilities patch switched this code from an explicit check > > of cap_t(p->cap_effective) to using __capable(). That means that > > now being glossed over by the oom killer means PF_SUPERPRIV will > > be set. Is that intentional? > > Yes, I switched the check because the old one didn't work with the new > capability representation. > > However, I had not thought this aspect of this replacement through. At > the time, it seemed obvious but in this case it actually depends on > whether you think using privilege (PF_SUPERPRIV) means "benefited from > privilege", or "successfully completed a privileged operation". > > I suspect, in this case, the correct thing to do is add the equivalent of: > > #define CAPABLE_PROBE_ONLY(a,b) (!security_capable(a,b)) > > and use that in the code in question. That is, return to the old > behavior in a way that will not break if we ever need to add more bits. I'm struggling to understand whether the above was an ack, a nack or a quack. > Thanks for finding this. >From that I'll assume ack ;)