linux-kernel - Re: [PATCH v3 08/30] kho: don't unpreserve memory during abort

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: <CA+CK2bDDo7xVxFd=-vkkXuUyStj9ShmURmGNPkMyJvi96KrV7Q@mail.gmail.com>
Date: Mon, 22 Sep 2025 10:57:39 -0400
From: Pasha Tatashin <pasha.tatashin@...een.com>
To: Jason Gunthorpe <jgg@...dia.com>
Cc: pratyush@...nel.org, jasonmiu@...gle.com, graf@...zon.com, 
	changyuanl@...gle.com, rppt@...nel.org, dmatlack@...gle.com, 
	rientjes@...gle.com, corbet@....net, rdunlap@...radead.org, 
	ilpo.jarvinen@...ux.intel.com, kanie@...ux.alibaba.com, ojeda@...nel.org, 
	aliceryhl@...gle.com, masahiroy@...nel.org, akpm@...ux-foundation.org, 
	tj@...nel.org, yoann.congal@...le.fr, mmaurer@...gle.com, 
	roman.gushchin@...ux.dev, chenridong@...wei.com, axboe@...nel.dk, 
	mark.rutland@....com, jannh@...gle.com, vincent.guittot@...aro.org, 
	hannes@...xchg.org, dan.j.williams@...el.com, david@...hat.com, 
	joel.granados@...nel.org, rostedt@...dmis.org, anna.schumaker@...cle.com, 
	song@...nel.org, zhangguopeng@...inos.cn, linux@...ssschuh.net, 
	linux-kernel@...r.kernel.org, linux-doc@...r.kernel.org, linux-mm@...ck.org, 
	gregkh@...uxfoundation.org, tglx@...utronix.de, mingo@...hat.com, 
	bp@...en8.de, dave.hansen@...ux.intel.com, x86@...nel.org, hpa@...or.com, 
	rafael@...nel.org, dakr@...nel.org, bartosz.golaszewski@...aro.org, 
	cw00.choi@...sung.com, myungjoo.ham@...sung.com, yesanishhere@...il.com, 
	Jonathan.Cameron@...wei.com, quic_zijuhu@...cinc.com, 
	aleksander.lobakin@...el.com, ira.weiny@...el.com, 
	andriy.shevchenko@...ux.intel.com, leon@...nel.org, lukas@...ner.de, 
	bhelgaas@...gle.com, wagi@...nel.org, djeffery@...hat.com, 
	stuart.w.hayes@...il.com, ptyadav@...zon.de, lennart@...ttering.net, 
	brauner@...nel.org, linux-api@...r.kernel.org, linux-fsdevel@...r.kernel.org, 
	saeedm@...dia.com, ajayachandra@...dia.com, parav@...dia.com, 
	leonro@...dia.com, witu@...dia.com
Subject: Re: [PATCH v3 08/30] kho: don't unpreserve memory during abort

On Thu, Aug 14, 2025 at 9:30 AM Jason Gunthorpe <jgg@...dia.com> wrote:
>
> On Thu, Aug 07, 2025 at 01:44:14AM +0000, Pasha Tatashin wrote:
> >  static int __kho_abort(void)
> >  {
> > -     int err = 0;
> > -     unsigned long order;
> > -     struct kho_mem_phys *physxa;
> > -
> > -     xa_for_each(&kho_out.track.orders, order, physxa) {
> > -             struct kho_mem_phys_bits *bits;
> > -             unsigned long phys;
> > -
> > -             xa_for_each(&physxa->phys_bits, phys, bits)
> > -                     kfree(bits);
> > -
> > -             xa_destroy(&physxa->phys_bits);
> > -             kfree(physxa);
> > -     }
> > -     xa_destroy(&kho_out.track.orders);
>
> Now nothing ever cleans this up :\

It is solved with stateless KHO. The current implementation is broken,
dropping everything in abort should never happen for stuff that was
independently preserved.

> Are you sure the issue isn't in the caller that it shouldn't be
> calling kho abort until all the other stuff is cleaned up first?
>
> I feel like this is another case of absuing globals gives an unclear
> lifecycle model.

Yes. But, we have a fix for that.

Pasha