Re: [PATCH 3/3 RESEND] auditsc: Do not use RCU primitive to read from cred pointer

[Richard Guy Briggs]

On 2020-04-03 17:43, Paul Moore wrote:
> On Fri, Apr 3, 2020 at 5:22 PM Richard Guy Briggs <rgb@xxxxxxxxxx> wrote:
> > On 2020-04-03 13:26, Amol Grover wrote:
> > > On Thu, Apr 02, 2020 at 08:56:36AM -0400, Paul Moore wrote:
> > > > On Thu, Apr 2, 2020 at 1:57 AM Amol Grover <frextrite@xxxxxxxxx> wrote:
> > > > > task_struct::cred is only used task-synchronously and does
> > > > > not require any RCU locks, hence, rcu_dereference_check is
> > > > > not required to read from it.
> > > > >
> > > > > Suggested-by: Jann Horn <jannh@xxxxxxxxxx>
> > > > > Co-developed-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> > > > > Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> > > > > Signed-off-by: Amol Grover <frextrite@xxxxxxxxx>
> > > > > ---
> > > > >  kernel/auditsc.c | 15 +++++----------
> > > > >  1 file changed, 5 insertions(+), 10 deletions(-)
> > > >
> > > > This is the exact same patch I ACK'd back in February, yes?
> > > >
> > > > https://lore.kernel.org/linux-audit/CAHC9VhQCbg1V290bYEZM+izDPRpr=XYXakohnDaMphkBBFgUaA@xxxxxxxxxxxxxx
> > > >
> > >
> > > Hi Paul,
> > >
> > > That's correct. I've resend the series out of the fear that the first 2
> > > patches might've gotten lost as it's been almost a month since I last
> > > sent them. Could you please ack this again, and if you don't mind could
> > > you please go through the other 2 patches and ack them aswell?
> >
> > Via who's tree are you expecting this will make it upstream?
> 
> When I asked a similar question back in February the response was
> basically not the audit tree.

Well, I went checking mingo and akpm's trees and didn't find 1/3 and 2/3
there even though I thought 3/3 was in audit/stable-5.6.  I was mistaken,
that patch in audit/stable-5.6 is a previous rcu fix for auditd_conn and
not 3/3.

> paul moore

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
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