From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com Date: Thu, 14 Apr 2016 22:01:02 +0200 From: Pavel Machek Message-ID: <20160414200102.GB3856@amd> References: <20160412221659.GA18102@www.outflux.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160412221659.GA18102@www.outflux.net> Subject: [kernel-hardening] Re: [PATCH v2] kaslr: allow kASLR to be default over Hibernation To: Kees Cook Cc: Linus Torvalds , "Rafael J. Wysocki" , Ingo Molnar , James Morse , Ard Biesheuvel , Matt Redfearn , Yves-Alexis Perez , Emrah Demir , Jonathan Corbet , x86@kernel.org, Len Brown , Borislav Petkov , Andy Lutomirski , linux-doc@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com List-ID: Hi! > Since kASLR and Hibernation can not currently coexist at runtime > on x86, the default behavior was to disable kASLR by default when > CONFIG_HIBERNATION was present (to retain original behavior). > > The behavior of kASLR on arm64 (and soon MIPS) is to be enabled by > default when selected at build time. Since arm64 Hibernation does not > conflict with kASLR, this fixes the hibernation argument parsing to be > x86-specific. Additionally, since end users want to be able to select > kASLR on x86 by default at build time, create CONFIG_RANDOMIZE_BASE_ON > that is present only on x86. > > Signed-off-by: Kees Cook I believe this is bad idea. arm64 shows that kaslr and hibernation can coexist, and hibernation is still useful when your battery runs out. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html