From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?utf-8?Q?St=C3=A9phane?= Aulery Subject: Re: clearenv(3): implies that it's a security tool Date: Fri, 19 Feb 2016 13:25:07 +0100 (CET) Message-ID: <1074498453.89962320.1455884707598.JavaMail.root@zimbra51-e8.priv.proxad.net> References: Reply-To: =?utf-8?Q?St=C3=A9phane?= Aulery Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-man-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: mtk manpages Cc: Matt Zimmerman , 679323-61a8vm9lEZVf4u+23C9RwQ@public.gmane.org, linux-man List-Id: linux-man@vger.kernel.org Hello Michael and Matt, ----- Michael Kerrisk (man-pages) a =C3=A9crit= =C2=A0: > On 18 February 2016 at 21:34, Matt Zimmerman wrote: > > Thanks for following up. My recommendation is to say something lik= e: > > > > This function DOES NOT securely erase the contents of the environme= nt. > > Security-conscious applications which need to do this should use ..= =2E. > > instead. >=20 > So, I think this report is a little confused, but mainly because of > the poor description in the man page. >=20 > The security-conscious applications in this context are those that > want to precisely control the environment passed to an exec()ed > program. clearenv() cannot, indeed must not, try to erase the buffers > containing the environment definitions. (See putenv(3) to understand > why.) I've adjusted the man page in away that I hope explains things > better: >=20 > The clearenv() function may be useful in security-consci= ous > applications that want to precisely control the environment t= hat > is passed to programs executed using exec(3). The applicat= ion > would do this by first clearing the environment and then add= ing > select environment variables. >=20 > Note that the main effect of clearenv() is to adjust the value= of > the pointer environ(7); this function does not erase the conte= nts > of the buffers containing the environment definitions. It's much better that I can do. If no objection Matt, I pass the bug report in fixed-upstream. Regards, --=20 St=C3=A9phane Aulery -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html