From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1EE6DC43219 for ; Thu, 2 May 2019 09:23:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA77F2075E for ; Thu, 2 May 2019 09:23:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726297AbfEBJX1 (ORCPT ); Thu, 2 May 2019 05:23:27 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([146.101.78.151]:27276 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726205AbfEBJX1 (ORCPT ); Thu, 2 May 2019 05:23:27 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-61-pyNgKG8xNWSOj78Z1oKZAg-1; Thu, 02 May 2019 10:23:22 +0100 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Thu, 2 May 2019 10:23:21 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Thu, 2 May 2019 10:23:21 +0100 From: David Laight To: "'Reshetova, Elena'" , Andy Lutomirski CC: Theodore Ts'o , Eric Biggers , "ebiggers@google.com" , "herbert@gondor.apana.org.au" , Ingo Molnar , Peter Zijlstra , "keescook@chromium.org" , Daniel Borkmann , "luto@kernel.org" , "linux-kernel@vger.kernel.org" , "jpoimboe@redhat.com" , "jannh@google.com" , "Perla, Enrico" , "mingo@redhat.com" , "bp@alien8.de" , "tglx@linutronix.de" , "gregkh@linuxfoundation.org" , "Edgecombe, Rick P" Subject: RE: [PATCH] x86/entry/64: randomize kernel stack offset upon syscall Thread-Topic: [PATCH] x86/entry/64: randomize kernel stack offset upon syscall Thread-Index: AQHU9E1UquBTkhVACE2y3BuRFoekIqY8wW2AgAAdM1CAAXexAIAANZ3ggAAW1gCAAApRgIAAMeKAgAAd+PCAAQuGgIAAYQuAgAAKhwCACsPi4IADJTwAgAAcagCAAExngIAEBbGAgACIbACAAbyQ8IAA9yhggAF9YoCAABkBsA== Date: Thu, 2 May 2019 09:23:21 +0000 Message-ID: <2e55aeb3b39440c0bebf47f0f9522dd8@AcuMS.aculab.com> References: <2236FBA76BA1254E88B949DDB74E612BA4C51962@IRSMSX102.ger.corp.intel.com> <20190416120822.GV11158@hirez.programming.kicks-ass.net> <01914abbfc1a4053897d8d87a63e3411@AcuMS.aculab.com> <20190416154348.GB3004@mit.edu> <2236FBA76BA1254E88B949DDB74E612BA4C52338@IRSMSX102.ger.corp.intel.com> <9cf586757eb44f2c8f167abf078da921@AcuMS.aculab.com> <20190417151555.GG4686@mit.edu> <99e045427125403ba2b90c2707d74e02@AcuMS.aculab.com> <2236FBA76BA1254E88B949DDB74E612BA4C5E473@IRSMSX102.ger.corp.intel.com> <2236FBA76BA1254E88B949DDB74E612BA4C63E24@IRSMSX102.ger.corp.intel.com> <20190426140102.GA4922@mit.edu> <57357E35-3D9B-4CA7-BAB9-0BE89E0094D2@amacapital.net> <2236FBA76BA1254E88B949DDB74E612BA4C66A8A@IRSMSX102.ger.corp.intel.com> <6860856C-6A92-4569-9CD8-FF6C5C441F30@amacapital.net> <2236FBA76BA1254E88B949DDB74E612BA4C6A4D7@IRSMSX102.ger.corp.intel.com> <303fc4ee5ac04e4fac104df1188952e8@AcuMS.aculab.com> <2236FBA76BA1254E88B949DDB74E612BA4C6C2C3@IRSMSX102.ger.corp.intel.com> In-Reply-To: <2236FBA76BA1254E88B949DDB74E612BA4C6C2C3@IRSMSX102.ger.corp.intel.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-MC-Unique: pyNgKG8xNWSOj78Z1oKZAg-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RnJvbTogUmVzaGV0b3ZhLCBFbGVuYQ0KPiBTZW50OiAwMiBNYXkgMjAxOSAwOToxNg0KLi4uDQo+ ID4gSSdtIGFsc28gZ3Vlc3NpbmcgdGhhdCBnZXRfY3B1X3ZhcigpIGRpc2FibGVzIHByZS1lbXB0 aW9uPw0KPiANCj4gWWVzLCBpbiBteSB1bmRlcnN0YW5kaW5nOg0KPiANCj4gI2RlZmluZSBnZXRf Y3B1X3Zhcih2YXIpCQkJCQkJXA0KPiAoKih7CQkJCQkJCQkJXA0KPiAJcHJlZW1wdF9kaXNhYmxl KCk7CQkJCQkJXA0KPiAJdGhpc19jcHVfcHRyKCZ2YXIpOwkJCQkJCVwNCj4gfSkpDQo+IA0KPiA+ IFRoaXMgY29kZSBjb3VsZCBwcm9iYWJseSBydW4gJ2Zhc3QgYW5kIGxvb3NlJyBhbmQganVzdCBp Z25vcmUNCj4gPiB0aGUgZmFjdCB0aGF0IHByZS1lbXB0aW9uIHdvdWxkIGhhdmUgb2RkIGVmZmVj dHMuDQo+ID4gQWxsIGl0IHdvdWxkIGRvIGlzIHBlcnR1cmIgdGhlIHJhbmRvbW5lc3MhDQo+IA0K PiBIbS4uIEkgc2VlIHlvdXIgcG9pbnQsIGJ1dCBJIGFtIHdvbmRlcmluZyB3aGF0IHRoZSBvZGQg ZWZmZWN0cyBtaWdodA0KPiBiZS4uIGkuZS4gY2FuIHdlIGVuZCB1cCB1c2luZyB0aGUgc2FtZSBy YW5kb20gYml0cyB0d2ljZSBmb3IgdHdvIG9yIG1vcmUNCj4gZGlmZmVyZW50IHN5c2NhbGxzIGFu ZCBhdHRhY2tlcnMgY2FuIHRyeSB0byB0cmlnZ2VyIHRoaXMgc2l0dWF0aW9uPw0KDQpUbyB0cmln Z2VyIGl0IHlvdSdkIG5lZWQgdG8gYXJyYW5nZSBmb3IgYW4gaW50ZXJydXB0IGluIHRoZSByaWdo dA0KdGltaW5nIHdpbmRvdyB0byBjYXVzZSBhbm90aGVyIHByb2Nlc3MgdG8gcnVuLg0KVGhlcmUg YXJlIGFsbW9zdCBjZXJ0YWlubHkgZWFzaWVyIHdheXMgdG8gYnJlYWsgdGhpbmdzLg0KDQpJIHRo aW5rIHRoZSBtYWluIGVmZmVjdHMgd291bGQgYmUgdGhlIGluY3JlbWVudCB3cml0aW5nIHRvIGEg ZGlmZmVyZW50DQpjcHUgbG9jYWwgZGF0YSAoY2F1c2luZyB0aGUgc2FtZSBkYXRhIHRvIGJlIHVz ZWQgYWdhaW4gYW5kL29yIHNraXBwZWQpDQphbmQgdGhlIHBvdGVudGlhbCBmb3IgdXBkYXRpbmcg dGhlIHJhbmRvbSBidWZmZXIgb24gdGhlICd3cm9uZyBjcHUnLg0KDQpTbyBzb21ldGhpbmcgbGlr ZToNCgkvKiBXZSBkb24ndCByZWFsbHkgY2FyZSBpZiB0aGUgdXBkYXRlIGlzIHdyaXR0ZW4gdG8g dGhlICd3cm9uZycNCgkgKiBjcHUgb3IgaWYgdGhlIHZhbGUgY29tZXMgZnJvbSB0aGUgd3Jvbmcg YnVmZmVyLiAqLw0KCW9mZnNldCA9ICp0aGlzX2NwdV9wdHIoJmNwdV9zeXNjYWxsX3JhbmRfb2Zm c2V0KTsNCgkqdGhpc19jcHVfcHRyKCZjcHVfc3lzY2FsbF9yYW5kX29mZnNldCkgPSBvZmZzZXQg KyAxOw0KCQ0KCWlmICgob2Zmc2V0ICY9IDQwOTUpKSByZXR1cm4gdGhpc19jcHVfcHRyKCZjcHVf c3lzY2FsbF9yYW5kX2J1ZmZlcilbb2Zmc2V0XTsNCg0KCWJ1ZmZlciA9IGdldF9jcHVfdmFyKCgm Y3B1X3N5c2NhbGxfcmFuZF9idWZmZXIpOw0KCWdldF9yYW5kb21fYnl0ZXMoKTsNCgl2YWwgPSBi dWZmZXJbMF07DQoJLyogbWF5YmUgc2V0IGNwdV9zeXNjYWxsX3JhbmRfb2Zmc2V0IHRvIDEgKi8N CglwdXRfY3B1X3ZhcigpOw0KCXJldHVybiB2YWw7DQoNClRoZSB3aG9sZSB0aGluZyBtaWdodCBl dmVuIHdvcmsgd2l0aCBhIGdsb2JhbCBidWZmZXIhDQoNCglEYXZpZA0KDQoNCgkNCg0KLQ0KUmVn aXN0ZXJlZCBBZGRyZXNzIExha2VzaWRlLCBCcmFtbGV5IFJvYWQsIE1vdW50IEZhcm0sIE1pbHRv biBLZXluZXMsIE1LMSAxUFQsIFVLDQpSZWdpc3RyYXRpb24gTm86IDEzOTczODYgKFdhbGVzKQ0K