From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/7418 Path: news.gmane.org!not-for-mail From: Harald Becker Newsgroups: gmane.linux.lib.musl.general Subject: Re: Re: Security advisory for musl libc - stack-based buffer overflow in ipv6 literal parsing [CVE-2015-1817] Date: Sat, 18 Apr 2015 17:49:51 +0200 Message-ID: <55327D1F.5070807@gmx.de> References: <20150417131008.GE17615@ucc.gu.uwa.edu.au> <20150417172327.GB6817@brightrain.aerifal.cx> <20150417180325.GC6817@brightrain.aerifal.cx> <20150417180907.GA26856@openwall.com> <20150418133202.GG17615@ucc.gu.uwa.edu.au> <20150418152542.GG6817@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1429372218 14996 80.91.229.3 (18 Apr 2015 15:50:18 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 18 Apr 2015 15:50:18 +0000 (UTC) Cc: Matt Johnston To: musl@lists.openwall.com Original-X-From: musl-return-7431-gllmg-musl=m.gmane.org@lists.openwall.com Sat Apr 18 17:50:16 2015 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1YjV0a-0007iu-3L for gllmg-musl@m.gmane.org; Sat, 18 Apr 2015 17:50:16 +0200 Original-Received: (qmail 13820 invoked by uid 550); 18 Apr 2015 15:50:14 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 13802 invoked from network); 18 Apr 2015 15:50:14 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 In-Reply-To: <20150418152542.GG6817@brightrain.aerifal.cx> X-Provags-ID: V03:K0:T+KA9B9YbxZK9LpCqRMGItWSHGsxBF9IdhXFhJ6mBBHnkBaJwE/ TZR1l7Bhph8tGEyfdis+BOhDdh0WDscgKRueO9F7iH1g5pt6g9GC20fDlkeQQ+jkubNcRYU hkVTWQmBDse6PPt/as+MlJku+yW/nccdXP2i/Mw1tA9LBrXm1JL83FFxlIIhG9I4JMtxLWU dTH7caFQ3T06tkL9ZZ39w== X-UI-Out-Filterresults: notjunk:1; Xref: news.gmane.org gmane.linux.lib.musl.general:7418 Archived-At: On 18.04.2015 17:25, Rich Felker wrote: >> The server hostkey will remain in process >> memory since it's required for rekeying - not as bad as root >> code execution though. > > Ugly. I don't see how this can be solved without a more advanced > privsep model. I agree it's lower-severity though. IMO you may put the host keys in a file readable (not writable) with a dropbear group, and only using that group for dropbear (no other users or programs using that group). So you may read the keys even if not root, if you add this dropbear group to setgroups (not setgid) before dropping root privileges. Harald