From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <1505906284.3490.5.camel@opteya.com> From: Yann Droneaud Date: Wed, 20 Sep 2017 13:18:04 +0200 In-Reply-To: <20170919171600.GA31441@openwall.com> References: <20170524155751.424-1-riel@redhat.com> <20170919171600.GA31441@openwall.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [kernel-hardening] [PATCH v2 0/5] stackprotector: ascii armor the stack canary To: Solar Designer , riel@redhat.com Cc: linux-kernel@vger.kernel.org, danielmicay@gmail.com, tytso@mit.edu, keescook@chromium.org, hpa@zytor.com, luto@amacapital.net, mingo@kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux-sh@vger.kernel.org, ysato@users.sourceforge.jp, kernel-hardening@lists.openwall.com List-ID: Hi, Le mardi 19 septembre 2017 à 19:16 +0200, Solar Designer a écrit : > > We could put/require a NUL in the middle of the canary, > but with the full canary being only 64-bit at most that would also > make some attacks easier. > Are you suggesting to randomly select which byte to set to 0 in each canary ? Regards. -- Yann Droneaud OPTEYA From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann Droneaud Date: Wed, 20 Sep 2017 11:18:04 +0000 Subject: Re: [kernel-hardening] [PATCH v2 0/5] stackprotector: ascii armor the stack canary Message-Id: <1505906284.3490.5.camel@opteya.com> List-Id: References: <20170524155751.424-1-riel@redhat.com> <20170919171600.GA31441@openwall.com> In-Reply-To: <20170919171600.GA31441@openwall.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: Solar Designer , riel@redhat.com Cc: linux-kernel@vger.kernel.org, danielmicay@gmail.com, tytso@mit.edu, keescook@chromium.org, hpa@zytor.com, luto@amacapital.net, mingo@kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux-sh@vger.kernel.org, ysato@users.sourceforge.jp, kernel-hardening@lists.openwall.com Hi, Le mardi 19 septembre 2017 à 19:16 +0200, Solar Designer a écrit : > > We could put/require a NUL in the middle of the canary, > but with the full canary being only 64-bit at most that would also > make some attacks easier. > Are you suggesting to randomly select which byte to set to 0 in each canary ? Regards. -- Yann Droneaud OPTEYA From mboxrd@z Thu Jan 1 00:00:00 1970 From: ydroneaud@opteya.com (Yann Droneaud) Date: Wed, 20 Sep 2017 13:18:04 +0200 Subject: [kernel-hardening] [PATCH v2 0/5] stackprotector: ascii armor the stack canary In-Reply-To: <20170919171600.GA31441@openwall.com> References: <20170524155751.424-1-riel@redhat.com> <20170919171600.GA31441@openwall.com> Message-ID: <1505906284.3490.5.camel@opteya.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, Le mardi 19 septembre 2017 ? 19:16 +0200, Solar Designer a ?crit : > > We could put/require a NUL in the middle of the canary, > but with the full canary being only 64-bit at most that would also > make some attacks easier. > Are you suggesting to randomly select which byte to set to 0 in each canary ? Regards. -- Yann Droneaud OPTEYA