linux-kernel - Re: [PATCH] xhci: fix null-pointer dereference when destroying half-built segment rings

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Mon, 12 Nov 2012 10:03:37 -0800
From:	Sarah Sharp <sarah.a.sharp@...ux.intel.com>
To:	Julius Werner <jwerner@...gle.com>
Cc:	Andy Shevchenko <andy.shevchenko@...il.com>,
	Julius Werner <jwerner@...omium.org>,
	linux-kernel@...r.kernel.org, linux-usb@...r.kernel.org,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Vincent Palatin <vpalatin@...omium.org>
Subject: Re: [PATCH] xhci: fix null-pointer dereference when destroying
 half-built segment rings

On Thu, Nov 01, 2012 at 01:28:46PM -0700, Julius Werner wrote:
> >> Is it just
> >> for (prev = *first; prev; prev = prev->next)
> >>    xhci_segment_free(xhci, prev);
> >> 
> >> ?
> > 
> > Yeah, that seems cleaner.
> > 
> > Sarah Sharp
> 
> I can submit it that way if you want, but I would advise against it. This way you access the prev pointer after it has been freed already… that's probably not a problem in the current kernel, but it depends on how the underlying memory is managed and is generally just not a good idea in my opinion.

Yep, you're right.  I'll take the second patch you submitted, thanks.

Sarah Sharp
--
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/