lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 19 Jul 2022 10:27:00 -0700 From: Linus Torvalds <torvalds@...ux-foundation.org> To: Sami Tolvanen <samitolvanen@...gle.com> Cc: David Laight <David.Laight@...lab.com>, Thomas Gleixner <tglx@...utronix.de>, Joao Moreira <joao@...rdrivepizza.com>, Peter Zijlstra <peterz@...radead.org>, LKML <linux-kernel@...r.kernel.org>, "the arch/x86 maintainers" <x86@...nel.org>, Tim Chen <tim.c.chen@...ux.intel.com>, Josh Poimboeuf <jpoimboe@...nel.org>, "Cooper, Andrew" <andrew.cooper3@...rix.com>, Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>, Johannes Wikner <kwikner@...z.ch>, Alyssa Milburn <alyssa.milburn@...ux.intel.com>, Jann Horn <jannh@...gle.com>, "H.J. Lu" <hjl.tools@...il.com>, "Moreira, Joao" <joao.moreira@...el.com>, "Nuzman, Joseph" <joseph.nuzman@...el.com>, Steven Rostedt <rostedt@...dmis.org>, "Gross, Jurgen" <jgross@...e.com>, Masami Hiramatsu <mhiramat@...nel.org>, Alexei Starovoitov <ast@...nel.org>, Daniel Borkmann <daniel@...earbox.net>, Peter Collingbourne <pcc@...gle.com> Subject: Re: [patch 00/38] x86/retbleed: Call depth tracking mitigation On Tue, Jul 19, 2022 at 10:23 AM Sami Tolvanen <samitolvanen@...gle.com> wrote: > > The preamble hash is encoded into an instruction just to avoid special > casing objtool, which would otherwise get confused about the random > bytes. On arm64, we just emit a bare constant before the function. Ahh. I think objtool would want to understand about kCFI anyway, so I think in the long run that hack isn't a goog idea. But I get why you'd do it as a "do this as just a compiler thing and hide it from objtool" as a development strategy. Linus
Powered by blists - more mailing lists