From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com Date: Sun, 9 Oct 2016 21:37:31 +0200 From: Jann Horn Message-ID: <20161009193731.GD14666@pc.thejh.net> References: <1476016472.2329.38.camel@cvidal.org> <1476040182.2329.72.camel@cvidal.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="mPYgjWmOFizS0g23" Content-Disposition: inline In-Reply-To: <1476040182.2329.72.camel@cvidal.org> Subject: Re: [kernel-hardening] self introduction To: Colin Vidal Cc: kernel-hardening@lists.openwall.com List-ID: --mPYgjWmOFizS0g23 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Oct 09, 2016 at 09:09:42PM +0200, Colin Vidal wrote: > Hi David, >=20 > > If you're interested, the HARDENED_ATOMIC team is looking for people > > to help porting the feature to other architectures.=A0=A0ARM is a > > reasonable candidate for someone new to the project.=A0=A0I have begun > > this effort myself, but if you'd like to collaborate I'd be > > grateful. >=20 > Sounds good! >=20 > > It essentially involves porting the original arch-specific features > > from PAX_REFCOUNT into Elena Reshetova's official HARDENED_ATOMIC > > tree, which can be found at > > https://github.com/esreshetova/linux-stable >=20 > The link seems broken (https://github.com/esreshetova too). I found > https://github.com/dwindsor/hardened-atomic but it is empty. Did I > miss something/Github filter? Typo in the link, I think? https://github.com/ereshetova/linux-stable > > Please contact me if you have any questions; I'd be glad to help! >=20 > I actually have question. :-) As far as I understand, PAX_REFCOUNT [1] > is mainly a x86-only No, PAX_REFCOUNT also supports a bunch of other architectures. As far as I can tell from a quick look: ARM, MIPS, PowerPC and SPARC. > port from PaX project It is part of the PaX patch. > in order to avoid overflow > on atomic_t variable (and avoid use-after-free exploits) Yes - overflow (beyond INT_MAX) and underflow (beyond INT_MIN). =2E I am a > little bit confused about the Elena patch-set HARDENED_ATOMIC [2]. It > is a more mature/recent version of the port, isn't it ? HARDENED_ATOMIC is a patch based on PAX_REFCOUNT that is developed with the intent to merge it into the upstream kernel. --mPYgjWmOFizS0g23 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJX+px7AAoJED4KNFJOeCOoPJQP/20UNfdXs4cuUztq4JYJJwsf MSzgWAV7HICOeZEfe0lfT8jZFPXHUXUSM2V3Kc5KL/YG08q9lXlxE21t2LEwBNhp thm/f0KeoJgI5dQAh4T9DU8u0G1MJxaHfshTNELaJEaYlFMnJiXx9+W2itO7/xjJ YYDwxT8fzybApiuFvPmk3Nl+1tq32PhGRXOOEnkIwT2autJDTR5FBJqM8BknkUC8 DL8rHYAC2VAAKFeufV+8Rl0XATgju+ASU0bpNA92OpXBHy6SyczerqTefcv0IKuz qqMf8UPhfNJgONSRgrbqLeUfb38JAHmw8T9VTzSJJxqmstYzwkt5BDJiud5mjBug OTnIuxP2bim+DapHcUzq/cHmelTMhnrYLKafss4iCNhFpNNyEv+fJTN0cEpqzog1 BYOmoOm6otyBWy9cK1Poi6vvYXMxNguApEyCWcQDmNy60PzavKZLp0s7KI3wH5ye fSHIg+yN3X4/HN7DY5QdCYUCQ5oovCdvWY1ZRyxlbUV1EXsA5HQv38ON5TeGizfp QLX3yE0BY4fB8rDTX6gYMlcj3+51o76Nud8Y+5ezDtQ1qGKnxuIo7mjJFnTBqwTk 8xzzjuS3huaKYvxZotmSXhXh3KgQShu+B0TaCq8C3BYd7GK9aooa8guhXTOEkr7B FxeIfjyi9xsuFRJ6G5D9 =TRpY -----END PGP SIGNATURE----- --mPYgjWmOFizS0g23--