linux-kernel - Re: [PATCH v2] driver core: Fix userspace expectations of uevent

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] [day] [month] [year] [list]

Message-ID: <2024102915-swiftly-almanac-9534@gregkh>
Date: Tue, 29 Oct 2024 01:21:35 +0100
From: Greg KH <gregkh@...uxfoundation.org>
To: Dan Williams <dan.j.williams@...el.com>
Cc: Thorsten Leemhuis <regressions@...mhuis.info>,
	rafael.j.wysocki@...el.com, tj@...nel.org,
	linux-kernel@...r.kernel.org, regressions@...ts.linux.dev
Subject: Re: [PATCH v2] driver core: Fix userspace expectations of
 uevent_show() as a probe barrier

On Mon, Oct 28, 2024 at 03:57:55PM -0700, Dan Williams wrote:
> Thorsten Leemhuis wrote:
> > On 08.10.24 02:26, Dan Williams wrote:
> > > Dan Williams wrote:
> > >> Changes since v1 [1]:
> > >> - Move the new "locked" infrastructure to private header files to make
> > >>   it clear it is not approved for general usage (Greg)
> > > 
> > > Greg, per the 0day report and further testing I am missing something
> > > subtle in using kernfs open files to pin device objects. So hold off on
> > > this for now until I can get that root caused. If someone else can spot
> > > what I missed feel free to chime in, but otherwise I will circle back.
> > > 
> > > If I don't get back to this before -rc6 I think the theoretical deadlock
> > > that would be re-introduced by a revert of 15fffc6a5624 would be
> > > preferable to this reported regression. I am not aware of any reports of
> > > that deadlock triggering in practice.
> > Was there any progress? If not: given that Linus prefers to have things
> > fixed by -rc6 I wonder if now would be a good time to get the revert on
> > track for a merge later this week.
> 
> Revert 15fffc6a5624 ("driver core: Fix uevent_show() vs driver detach
> race"), which reintroduces a theoretical lockdep splat, is my preference
> at this point.
> 
> Even if I had a new version of this replacement patch in hand today I
> would still want it to be v6.13 material, not v6.12-rc. It deserves a
> full kernel cycle soak time to shake out issues before release.

Ok, I'll do the revert in my tree and push it for the next -rc release
thanks.

greg k-h