linux-kernel - Re: [PATCH] i2c: imx: Fix external abort on early interrupt

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]

Date:   Fri, 12 Jun 2020 12:21:13 +0200
From:   Krzysztof Kozlowski <krzk@...nel.org>
To:     Wolfram Sang <wsa@...nel.org>
Cc:     Oleksij Rempel <linux@...pel-privat.de>,
        Pengutronix Kernel Team <kernel@...gutronix.de>,
        Shawn Guo <shawnguo@...nel.org>,
        Sascha Hauer <s.hauer@...gutronix.de>,
        Fabio Estevam <festevam@...il.com>,
        NXP Linux Team <linux-imx@....com>,
        linux-i2c@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, stable@...r.kernel.org
Subject: Re: [PATCH] i2c: imx: Fix external abort on early interrupt

On Fri, Jun 12, 2020 at 11:56:04AM +0200, Wolfram Sang wrote:
> On Fri, Jun 12, 2020 at 11:29:41AM +0200, Krzysztof Kozlowski wrote:
> > On Fri, Jun 12, 2020 at 11:05:17AM +0200, Wolfram Sang wrote:
> > > On Wed, Jun 10, 2020 at 03:46:42PM +0200, Krzysztof Kozlowski wrote:
> > > > If interrupt comes early (could be triggered with CONFIG_DEBUG_SHIRQ),
> > > 
> > > That code is disabled since 2011 (6d83f94db95c ("genirq: Disable the
> > > SHIRQ_DEBUG call in request_threaded_irq for now"))? So, you had this
> > > without fake injection, I assume?
> > 
> > No, I observed it only after enabling DEBUG_SHIRQ (to a kernel with
> > some debugging options already).
> 
> Interesting. Maybe probe was deferred and you got the extra irq when
> deregistering?

Yes, good catch. The abort happens right after deferred probe exit.  It
could be then different reason than I thought - the interrupt is freed
through devm infrastructure quite late.  At this time, the clock might
be indeed disabled (error path of probe()).

Best regards,
Krzysztof