linux-kernel - Re: [PATCH] mm/hotplug: Verify hotplug memory range

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:	Thu, 8 Aug 2013 15:53:48 -0400
From:	KOSAKI Motohiro <kosaki.motohiro@...il.com>
To:	Toshi Kani <toshi.kani@...com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	LKML <linux-kernel@...r.kernel.org>, dave@...1.net,
	Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com>,
	Tang Chen <tangchen@...fujitsu.com>,
	"vasilis.liaskovitis" <vasilis.liaskovitis@...fitbricks.com>
Subject: Re: [PATCH] mm/hotplug: Verify hotplug memory range

On Thu, Aug 8, 2013 at 12:47 PM, Toshi Kani <toshi.kani@...com> wrote:
> add_memory() and remove_memory() can only handle a memory range aligned
> with section.  There are problems when an unaligned range is added and
> then deleted as follows:
>
>  - add_memory() with an unaligned range succeeds, but __add_pages()
>    called from add_memory() adds a whole section of pages even though
>    a given memory range is less than the section size.
>  - remove_memory() to the added unaligned range hits BUG_ON() in
>    __remove_pages().
>
> This patch changes add_memory() and remove_memory() to check if a given
> memory range is aligned with section at the beginning.  As the result,
> add_memory() fails with -EINVAL when a given range is unaligned, and
> does not add such memory range.  This prevents remove_memory() to be
> called with an unaligned range as well.  Note that remove_memory() has
> to use BUG_ON() since this function cannot fail.
>
> Signed-off-by: Toshi Kani <toshi.kani@...com>
> ---
>  mm/memory_hotplug.c |   22 ++++++++++++++++++++++

memory_hotplug.c is maintained by me and kamezawa-san. Please cc us
if you have a subsequent patch.

Acked-by: KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>
--
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/