From mboxrd@z Thu Jan 1 00:00:00 1970 From: Casey Schaufler Subject: Re: security_path hooks for xattr Date: Thu, 26 Jan 2012 08:04:28 -0800 Message-ID: <4F21798C.5040205@schaufler-ca.com> References: <87fwf2y6mw.fsf@tucsk.pomaz.szeredi.hu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Cc: apparmor-nLRlyDuq1AZFpShjVBNYrg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, LSM , draht-IBi9RG/b67k@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Miklos Szeredi Return-path: In-Reply-To: <87fwf2y6mw.fsf-d8RdFUjzFsbxNFs70CDYszOMxtEWgIxa@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: apparmor-bounces-nLRlyDuq1AZFpShjVBNYrg@public.gmane.org Errors-To: apparmor-bounces-nLRlyDuq1AZFpShjVBNYrg@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org On 1/26/2012 4:45 AM, Miklos Szeredi wrote: > Forwarding from an internal bug report: > > "AppArmor does not mediate the xattr system calls for confined processes. > > As a consequence, a confined process can cross the confinement privilege > boundary by reading or writing to extended attributes that the confined > task should not have access to. The restrictions for security and user > attributes read and write still apply according to DAC; however, this > does not comply with the claim of AppArmor to mediate fipe > operations. The use of extended attributes is very flexible, so that the > effect of a missing mediation can lead to false assumptions in > subsequent policy decisions (eCryptfs)." > > AFAIU this boils down to missing security hooks in *xattr(). > > Would it be possible to add these hooks? Please post proposed patches to linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > > Thanks, > Miklos > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- AppArmor mailing list AppArmor-nLRlyDuq1AZFpShjVBNYrg@public.gmane.org Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/apparmor From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752880Ab2AZQK5 (ORCPT ); Thu, 26 Jan 2012 11:10:57 -0500 Received: from nm18.access.bullet.mail.mud.yahoo.com ([66.94.237.219]:48145 "HELO nm18.access.bullet.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751544Ab2AZQKy (ORCPT ); Thu, 26 Jan 2012 11:10:54 -0500 X-Greylist: delayed 382 seconds by postgrey-1.27 at vger.kernel.org; Thu, 26 Jan 2012 11:10:54 EST X-Yahoo-Newman-Id: 858431.47600.bm@smtp109.biz.mail.ne1.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: b63jKO8VM1mIqQirNVVpNaxvpfJIdH6KxC12o5soGh9G.6u .0JitmHsLpiZ_.Q8eo5L.xP6THoiO9Lq9lhDdm2svfEvUTV_I_.KtSshhG27 MieWUJlTXa3fxyxlCprIUUO23GbNoTzirZgGVDE9jT0NyOIVK.IXpMA5Pb9T OYa6uYwPAdZJkv7jZpKTEAd8ZLnlLjBIAzz7IT_NEl1ZgfC6ydJA33XNUC6w JX_lKdmbnkkVzvPZa4KRC86C5zCb9gx4T5gUZdYla_ngUDigNPpTnR99DDDg HxeCRImn_qk3cjGIb0cq6OXRf3rAtGVgOO2_uHRfTnmBaLogHiJFngGOBfhw v5BmarRjtmpe6kByvfzSLq257HHDso86YOYAIqY88sFWZsA72fg.iM0.7ygt CLaRYYm5BrZ6cAG5sMnBzoxXQIl8i7CZ.68rAYOf63cdeUL2t9zgSUfQ7aKx abIGfzsHhfSn_QU7D1maNEYlIpw-- X-Yahoo-SMTP: OIJXglSswBDfgLtXluJ6wiAYv6_cnw-- Message-ID: <4F21798C.5040205@schaufler-ca.com> Date: Thu, 26 Jan 2012 08:04:28 -0800 From: Casey Schaufler User-Agent: Mozilla/5.0 (Windows NT 6.0; rv:9.0) Gecko/20111222 Thunderbird/9.0.1 MIME-Version: 1.0 To: Miklos Szeredi CC: john.johansen@canonical.com, apparmor@lists.ubuntu.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, draht@suse.com, LSM Subject: Re: security_path hooks for xattr References: <87fwf2y6mw.fsf@tucsk.pomaz.szeredi.hu> In-Reply-To: <87fwf2y6mw.fsf@tucsk.pomaz.szeredi.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/26/2012 4:45 AM, Miklos Szeredi wrote: > Forwarding from an internal bug report: > > "AppArmor does not mediate the xattr system calls for confined processes. > > As a consequence, a confined process can cross the confinement privilege > boundary by reading or writing to extended attributes that the confined > task should not have access to. The restrictions for security and user > attributes read and write still apply according to DAC; however, this > does not comply with the claim of AppArmor to mediate fipe > operations. The use of extended attributes is very flexible, so that the > effect of a missing mediation can lead to false assumptions in > subsequent policy decisions (eCryptfs)." > > AFAIU this boils down to missing security hooks in *xattr(). > > Would it be possible to add these hooks? Please post proposed patches to linux-security-module@vger.kernel.org > > Thanks, > Miklos > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >