linux-kernel - Re: [PATCH v3 05/35] mm: introduce slabobj

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: <CAJuCfpGkdAy58nR02_PSVXc4=R3faRUL-7Hack3R_aWmAgk5HA@mail.gmail.com>
Date: Mon, 12 Feb 2024 18:20:13 -0800
From: Suren Baghdasaryan <surenb@...gle.com>
To: Kees Cook <keescook@...omium.org>
Cc: akpm@...ux-foundation.org, kent.overstreet@...ux.dev, mhocko@...e.com, 
	vbabka@...e.cz, hannes@...xchg.org, roman.gushchin@...ux.dev, mgorman@...e.de, 
	dave@...olabs.net, willy@...radead.org, liam.howlett@...cle.com, 
	corbet@....net, void@...ifault.com, peterz@...radead.org, 
	juri.lelli@...hat.com, catalin.marinas@....com, will@...nel.org, 
	arnd@...db.de, tglx@...utronix.de, mingo@...hat.com, 
	dave.hansen@...ux.intel.com, x86@...nel.org, peterx@...hat.com, 
	david@...hat.com, axboe@...nel.dk, mcgrof@...nel.org, masahiroy@...nel.org, 
	nathan@...nel.org, dennis@...nel.org, tj@...nel.org, muchun.song@...ux.dev, 
	rppt@...nel.org, paulmck@...nel.org, pasha.tatashin@...een.com, 
	yosryahmed@...gle.com, yuzhao@...gle.com, dhowells@...hat.com, 
	hughd@...gle.com, andreyknvl@...il.com, ndesaulniers@...gle.com, 
	vvvvvv@...gle.com, gregkh@...uxfoundation.org, ebiggers@...gle.com, 
	ytcoode@...il.com, vincent.guittot@...aro.org, dietmar.eggemann@....com, 
	rostedt@...dmis.org, bsegall@...gle.com, bristot@...hat.com, 
	vschneid@...hat.com, cl@...ux.com, penberg@...nel.org, iamjoonsoo.kim@....com, 
	42.hyeyoo@...il.com, glider@...gle.com, elver@...gle.com, dvyukov@...gle.com, 
	shakeelb@...gle.com, songmuchun@...edance.com, jbaron@...mai.com, 
	rientjes@...gle.com, minchan@...gle.com, kaleshsingh@...gle.com, 
	kernel-team@...roid.com, linux-doc@...r.kernel.org, 
	linux-kernel@...r.kernel.org, iommu@...ts.linux.dev, 
	linux-arch@...r.kernel.org, linux-fsdevel@...r.kernel.org, linux-mm@...ck.org, 
	linux-modules@...r.kernel.org, kasan-dev@...glegroups.com, 
	cgroups@...r.kernel.org
Subject: Re: [PATCH v3 05/35] mm: introduce slabobj_ext to support slab object extensions

On Mon, Feb 12, 2024 at 2:14 PM Kees Cook <keescook@...omium.org> wrote:
>
> On Mon, Feb 12, 2024 at 01:38:51PM -0800, Suren Baghdasaryan wrote:
> > Currently slab pages can store only vectors of obj_cgroup pointers in
> > page->memcg_data. Introduce slabobj_ext structure to allow more data
> > to be stored for each slab object. Wrap obj_cgroup into slabobj_ext
> > to support current functionality while allowing to extend slabobj_ext
> > in the future.
> >
> > Signed-off-by: Suren Baghdasaryan <surenb@...gle.com>
>
> It looks like this doesn't change which buckets GFP_KERNEL_ACCOUNT comes
> out of, is that correct? I'd love it if we didn't have separate buckets
> so GFP_KERNEL and GFP_KERNEL_ACCOUNT came from the same pools (so that
> the randomized pools would cover GFP_KERNEL_ACCOUNT ...)

This should not affect KMEM accounting in any way. We are simply
changing the vector of obj_cgroup objects to hold complex objects
which can contain more fields in addition to the original obj_cgroup
(in our case it's the codetag reference).
Unless I misunderstood your question?

>
> Regardless:
>
> Reviewed-by: Kees Cook <keescook@...omium.org>
>
> --
> Kees Cook