linux-kernel - Re: [PATCH] iommu/core: fix bus notifier breakage

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: <20140925144754.GD8306@8bytes.org>
Date:	Thu, 25 Sep 2014 16:47:54 +0200
From:	Joerg Roedel <joro@...tes.org>
To:	Mark Salter <msalter@...hat.com>
Cc:	iommu@...ts.linux-foundation.org, linux-kernel@...r.kernel.org,
	Suravee Suthikulpanit <Suravee.Suthikulpanit@....com>
Subject: Re: [PATCH] iommu/core: fix bus notifier breakage

On Sun, Sep 21, 2014 at 01:58:24PM -0400, Mark Salter wrote:
> iommu_bus_init() registers a bus notifier on the given bus by using
> a statically defined notifier block:
> 
>   static struct notifier_block iommu_bus_nb = {
>           .notifier_call = iommu_bus_notifier,
>   };
> 
> This same notifier block is used for all busses. This causes a
> problem for notifiers registered after iommu has registered this
> callback on multiple busses. The problem is that a subsequent
> notifier being registered on a bus which has this iommu notifier
> will also get linked in to the notifier list of all other busses
> which have this iommu notifier.
> 
> This patch fixes this by allocating the notifier_block at runtime.
> Some error checking is also added to catch any allocation failure
> or notifier registration error.
> 
> Signed-off-by: Mark Salter <msalter@...hat.com>
> ---
>  drivers/iommu/iommu.c | 26 ++++++++++++++++----------
>  1 file changed, 16 insertions(+), 10 deletions(-)

Makes sense, applied. Where have you hit this condition where IOMMUs for
different buses are registered?


	Joerg

--
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/