linux-kernel - Re: [PATCH 0/2] drm/nouveau: avoid usage of list iterator after loop

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <160cbdb25510df6f2e3194c6dd4a2c47a4ee70b7.camel@redhat.com>
Date:   Tue, 07 Mar 2023 17:46:45 -0500
From:   Lyude Paul <lyude@...hat.com>
To:     Jakob Koschel <jkl820.git@...il.com>,
        Ben Skeggs <bskeggs@...hat.com>,
        Karol Herbst <kherbst@...hat.com>,
        David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>
Cc:     dri-devel@...ts.freedesktop.org, nouveau@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org,
        Pietro Borrello <borrello@...g.uniroma1.it>,
        Cristiano Giuffrida <c.giuffrida@...nl>,
        "Bos, H.J." <h.j.bos@...nl>
Subject: Re: [PATCH 0/2] drm/nouveau: avoid usage of list iterator after loop

Actually hm, dim is warning me about this and making me realize there's
probably a better way to handle this, going to revoke the previous r-b I gave
and respond inline

On Tue, 2023-03-07 at 17:43 -0500, Lyude Paul wrote:
> Reviewed-by: Lyude Paul <lyude@...hat.com>
> 
> Will push upstream in just a moment
> 
> On Wed, 2023-03-01 at 18:25 +0100, Jakob Koschel wrote:
> > This patch set includes two instances where the list iterator variable
> > 'pstate' is implicitly assumed to be valid after the iterator loop.
> > While in pratice that is most likely the case (if
> > 'pstatei'/'args->v0.state' is <= the elements in clk->states), we should
> > explicitly only allow 'pstate' to always point to correct 'nvkm_pstate'
> > structs.
> > 
> > That allows catching potential bugs with BUG_ON(!pstate) that otherwise
> > would be completely undetectable.
> > 
> > It also helps the greater mission to hopefully move the list iterator
> > variable into the iterating macro directly [1].
> > 
> > Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
> > Signed-off-by: Jakob Koschel <jkl820.git@...il.com>
> > ---
> > Jakob Koschel (2):
> >       drm/nouveau/device: avoid usage of list iterator after loop
> >       drm/nouveau/clk: avoid usage of list iterator after loop
> > 
> >  drivers/gpu/drm/nouveau/nvkm/engine/device/ctrl.c | 9 ++++++---
> >  drivers/gpu/drm/nouveau/nvkm/subdev/clk/base.c    | 9 ++++++---
> >  2 files changed, 12 insertions(+), 6 deletions(-)
> > ---
> > base-commit: c0927a7a5391f7d8e593e5e50ead7505a23cadf9
> > change-id: 20230301-drm-nouveau-avoid-iter-after-loop-4bff97166efa
> > 
> > Best regards,
> 

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat