linux-kernel - Re: [PATCH v3 13/18] of: overlay: check prevents multiple fragments touching same property

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: <16f48648393366d91e43cd66b3d0a346b1ed29ab.camel@perches.com>
Date:   Sun, 14 Oct 2018 18:55:25 -0700
From:   Joe Perches <joe@...ches.com>
To:     Frank Rowand <frowand.list@...il.com>,
        Rob Herring <robh+dt@...nel.org>,
        Pantelis Antoniou <pantelis.antoniou@...sulko.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Alan Tull <atull@...nel.org>, Moritz Fischer <mdf@...nel.org>
Cc:     linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        devicetree@...r.kernel.org, linux-fpga@...r.kernel.org
Subject: Re: [PATCH v3 13/18] of: overlay: check prevents multiple fragments
 touching same property

On Sun, 2018-10-14 at 18:52 -0700, Frank Rowand wrote:
> On 10/14/18 18:06, Joe Perches wrote:
> > On Sun, 2018-10-14 at 17:24 -0700, frowand.list@...il.com wrote:
> > > From: Frank Rowand <frank.rowand@...y.com>
> > > 
> > > Add test case of two fragments updating the same property.  After
> > > adding the test case, the system hangs at end of boot, after
> > > after slub stack dumps from kfree() in crypto modprobe code.
[]
> > I think this is worse performance than before.
> > 
> > This now walks all entries when before it would
> > return -EINVAL directly when it found a match.
> 
> Yes, it is worse performance, but that is OK.
> 
> This is a check that is done when a devicetree overlay is applied.
> If an error occurs then that means that the overlay was incorrectly
> specified.  The file drivers/of/unittest-data/overlay_bad_add_dup_prop.dts
> in this patch provides an example of how a bad overlay can be created.
> 
> Once an error was detected, the check could return immediately, or it
> could continue to give a complete list of detected errors.  I chose to
> give the complete list of detected errors.

Swell.  Please describe that in the commit message.