From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764813AbYBGAXO (ORCPT ); Wed, 6 Feb 2008 19:23:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932512AbYBFX71 (ORCPT ); Wed, 6 Feb 2008 18:59:27 -0500 Received: from cantor.suse.de ([195.135.220.2]:46458 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932500AbYBFX7X (ORCPT ); Wed, 6 Feb 2008 18:59:23 -0500 Date: Wed, 6 Feb 2008 15:53:58 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Eric Paris , Alan Cox , Stephen Smalley , James Morris , Chris Wright , maximilian attems Subject: [patch 56/73] VM/Security: add security hook to do_brk (CVE-2007-6434) Message-ID: <20080206235358.GE13121@suse.de> References: <20080206234302.769849277@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="vm-security-add-security-hook-to-do_brk.patch" In-Reply-To: <20080206235015.GA13121@suse.de> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.23-stable review patch. If anyone has any objections, please let us know. ------------------ From: Eric Paris patch ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5 in mainline. VM/Security: add security hook to do_brk Given a specifically crafted binary do_brk() can be used to get low pages available in userspace virtual memory and can thus be used to circumvent the mmap_min_addr low memory protection. Add security checks in do_brk(). Signed-off-by: Eric Paris Acked-by: Alan Cox Cc: Stephen Smalley Cc: James Morris Cc: Chris Wright Cc: maximilian attems Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/mmap.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1938,6 +1938,10 @@ unsigned long do_brk(unsigned long addr, if (is_hugepage_only_range(mm, addr, len)) return -EINVAL; + error = security_file_mmap(0, 0, 0, 0, addr, 1); + if (error) + return error; + flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags; error = arch_mmap_check(addr, len, flags); --