linux-kernel - Re: [PATCH] power: Change device_wakeup_enable() to check for null dev

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: <3366600.jMpqPVojcG@vostro.rjw.lan>
Date:	Sat, 16 Nov 2013 01:32:05 +0100
From:	"Rafael J. Wysocki" <rjw@...ysocki.net>
To:	shuah.kh@...sung.com
Cc:	len.brown@...el.com, pavel@....cz, gregkh@...uxfoundation.org,
	linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
	shuahkhan@...il.com, anton@...msg.org, dwmw2@...radead.org,
	stable@...r.kernel.org
Subject: Re: [PATCH] power: Change device_wakeup_enable() to check for null dev_name(dev)

On Friday, November 15, 2013 05:16:31 PM Shuah Khan wrote:
> On 11/15/2013 05:21 PM, Rafael J. Wysocki wrote:
> > On Friday, November 15, 2013 05:03:57 PM Shuah Khan wrote:
> >> device_wakeup_enable() uses dev_name(dev) as the wakeup source name.
> >> When it gets called with a device with its name not yet set, ws structure
> >> with ws->name = NULL gets created.
> >>
> >> When kernel is booted with wakeup_source_activate enabled, it will panic
> >> when the trace point code tries to derefernces ws->name.
> >>
> >> Change device_wakeup_enable() to check for dev_name(dev) null condition
> >> and return -EINVAL to avoid panics when device_wakeup_enable() gets called
> >> before device is fully initialized with its name.
>   		return -EINVAL;
> >
> > Can you please use WARN_ON(!dev_name(dev)) here?  While I agree that it is a
> > bad idea to crash the kernel because dev has no name, that indicates a driver
> > bug that shouldn't be too easy to ignore.
> >
> > Thanks!
> >
> 
> Right. ok I will re-cut the patch with WARN_ON and send it. fyi I did 
> send fix for the driver (power_supply) as well.
> 
> http://www.kernelhub.org/?msg=362354&p=2

That's OK (thanks for taking care of this), but there may be more brilliant
stuff like that in the future and people should see right away that something's
wrong in those cases.

Rafael

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/