linux-kernel - Re: linux acpi (thunderbolt? bug)

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: <alpine.DEB.2.21.1802191823570.1853@nanos.tec.linutronix.de>
Date:   Mon, 19 Feb 2018 18:26:41 +0100 (CET)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Randy Dunlap <rdunlap@...radead.org>
cc:     Yuriy Vostrikov <delamonpansie@...il.com>,
        linux-kernel@...r.kernel.org, x86@...nel.org
Subject: Re: linux acpi (thunderbolt? bug)

On Mon, 19 Feb 2018, Randy Dunlap wrote:

> On 02/19/18 06:51, Thomas Gleixner wrote:
> >  	} else {
> > +		/*
> > +		 * Offline case: The current vector needs to be released in
> > +		 * the matrix allocator.
> > +		 */
> > +		if (apicd->vector &&
> 
> Drop the "apicd->vector &&" ? (redundant)

No. The else path is entered when

    apicd->vector == 0

or

    apicd->cpu is offline

So we need to check here for vector != 0 as otherwise we'd free vector 0
which is invalid. I'll add a comment explaining the mess.

> > +		    apicd->vector != MANAGED_IRQ_SHUTDOWN_VECTOR) {
> > +			irq_matrix_free(vector_matrix, apicd->cpu,
> > +					apicd->vector, managed);
> > +		}
> >  		apicd->prev_vector = 0;
> >  	}

Thanks,

	tglx