References: <1494327032-3035-1-git-send-email-steffan.karger@...1435...> From: David Sommerseth Message-ID: Date: Tue, 9 May 2017 20:23:25 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="3xHSSHAd03kW0XggvdHLs1dHUq6MgmXW8" Subject: Re: [Openvpn-devel] [PATCH] Always clear username/password from memory on error Reply-To: openvpn-devel@lists.sourceforge.net List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Selva Nair , "openvpn-devel@lists.sourceforge.net" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --3xHSSHAd03kW0XggvdHLs1dHUq6MgmXW8 Content-Type: multipart/mixed; boundary="cFWWwmRCm07mmpqpMAiMGXrDhLk6QVelS"; protected-headers="v1" From: David Sommerseth Reply-To: openvpn-devel@lists.sourceforge.net To: Selva Nair , "openvpn-devel@lists.sourceforge.net" Message-ID: Subject: Re: [Openvpn-devel] [PATCH] Always clear username/password from memory on error References: <1494327032-3035-1-git-send-email-steffan.karger@...1435...> In-Reply-To: --cFWWwmRCm07mmpqpMAiMGXrDhLk6QVelS Content-Language: en-GB Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On 09/05/17 20:08, Selva Nair wrote: > Hi, >=20 > On Tue, May 9, 2017 at 1:47 PM, David Sommerseth > > wrote: >=20 > That said, I think we should fix secure_memzero() to just return if t= he > input pointer is NULL. And even though most compilers do initialize > variables, I think it's good to be defensive here and initialize > `up` too. >=20 >=20 > No, compiler will not initialize such non-static local variables. In > fact in this case gcc will warn (with -Wall) that "up" may be used > uninitalized because of code paths where "up" is not allocated as you > pointed out. >=20 > In that sense its better not to initialize such variables as > initialization can hide errors. I agree that getting the warning is useful for developers. But I've just seen way too many packagers ignoring these warnings (or even removing -Wall) - and then ship binaries with undefined behaviour. I don't like that scenario at all. --=20 kind regards, David Sommerseth OpenVPN Technologies, Inc --cFWWwmRCm07mmpqpMAiMGXrDhLk6QVelS-- --3xHSSHAd03kW0XggvdHLs1dHUq6MgmXW8 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBCAAGBQJZEgkdAAoJEIbPlEyWcf3yFqUQAJ/3K046l8+Y4kmaHtmU3TtK tBa5LF4JJD8M8sc0TwYjaulNSEq1eGEL3EM2oHtD7aeSujly4S5kzH3cRrT4zvFe h7dCYl2H/+/TXnZdTUGEyY7OVM2jKzfHwpCAw6ooSoRFHvzQhtVp8TACIwztJBNA J5LH030fgmyP8TRrjbPkzOVEWjQcCMBVtz7U3Kj/6aq0fZWc2v9nKl8/e1W6Kd/k 7crClwFkndN/Qeq9/n5WGdWXuD+7KdYrVkLOrdvnTSQLlJNZzxQ9iv8JebIjBolQ nIzQcRTbTWgSWG5EILsu22O99lz4X0yCZaC46kP2w7Ax4a9faWZ91wKDh4TbJPIE AZe0qk6Dwc3k3tbM83KGG6OLVGqdoIf12XOMkG+13Wo7CjK+vYWWtjITcdy2tqnB j5VUyaFzG3WShJ3+L9bhP+BGxdPyGJ/H9n0OgqTLyVFV2xhTE9DQ06qCTvp8oAks +Fjfckv4WfCpXQkc+NPkSdx1IahRMocjnCKke3xyJiPpByYR7Zu/E/Vh9Qktt/V6 gFnZKEo++dkLuCTAIScfg9aff6Q5DEPZy/cAIiogn56gUhNnu+O4J4/QdTuBCIQi TC0woRE7MSj+3o+VC1pTnJw48g1KtzUz0ol4qx3N5SOzLu08ncyKFlSHjj7qOmHc U6y8mXbzo7PoUbMz62Nc =0n+0 -----END PGP SIGNATURE----- --3xHSSHAd03kW0XggvdHLs1dHUq6MgmXW8--