linux-kernel - Re: [PATCH 5/6] proc: make check_mem_permission() return an mm

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: <20110309151900.0403.A69D9226@jp.fujitsu.com>
Date:	Wed,  9 Mar 2011 15:20:16 +0900 (JST)
From:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>
To:	Stephen Wilson <wilsons@...rt.ca>
Cc:	kosaki.motohiro@...fujitsu.com, linux-mm@...ck.org,
	Andrew Morton <akpm@...ux-foundation.org>,
	Alexander Viro <viro@...iv.linux.org.uk>,
	Rik van Riel <riel@...hat.com>,
	Roland McGrath <roland@...hat.com>,
	Matt Mackall <mpm@...enic.com>,
	David Rientjes <rientjes@...gle.com>,
	Nick Piggin <npiggin@...nel.dk>,
	Andrea Arcangeli <aarcange@...hat.com>,
	Mel Gorman <mel@....ul.ie>, Ingo Molnar <mingo@...e.hu>,
	Michel Lespinasse <walken@...gle.com>,
	Hugh Dickins <hughd@...gle.com>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 5/6] proc: make check_mem_permission() return an mm_struct on success

> This change allows us to take advantage of access_remote_vm(), which in turn
> enables a secure mem_write() implementation.
> 
> The previous implementation of mem_write() was insecure since the target task
> could exec a setuid-root binary between the permission check and the actual
> write.  Holding a reference to the target mm_struct eliminates this
> vulnerability.
> 
> Signed-off-by: Stephen Wilson <wilsons@...rt.ca>

OK, I like this idea. So, I suppose you will resend newer version as applied Al's
comment and I'll be able to ack this.

Thanks.



--
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/