From patchwork Wed Jun 21 20:22:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thadeu Lima de Souza Cascardo X-Patchwork-Id: 1798107 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=canonical.com header.i=@canonical.com header.a=rsa-sha256 header.s=20210705 header.b=pwu1GTgs; dkim-atps=neutral Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4QmZhp6R1Vz20Xm for ; Thu, 22 Jun 2023 06:23:53 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1qC4Me-0002E0-7G; Wed, 21 Jun 2023 20:23:40 +0000 Received: from smtp-relay-canonical-1.internal ([10.131.114.174] helo=smtp-relay-canonical-1.canonical.com) by huckleberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1qC4Mc-0002Dn-Or for kernel-team@lists.ubuntu.com; Wed, 21 Jun 2023 20:23:38 +0000 Received: from localhost.localdomain (1.general.cascardo.us.vpn [10.172.70.58]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-1.canonical.com (Postfix) with ESMTPSA id CCB073FE08 for ; Wed, 21 Jun 2023 20:23:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1687379018; bh=ug1rtIm2Hbj1Ise145ij1nF/4b+YcWz6FsnqCvk7AVs=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=pwu1GTgspzOk2XQw4vwQsQjmj1vB6NX1a4bcwVNq0AZZsH0r+eQ4xkOQpL4T23Woy vhMkVm5y7WuajRdZTBcIHZrFLqY5vg0W9KLnJDc4DJFxJVM9In6CN43w3yivBSCiq+ BtK72m/nMgxbl4nQT2zoQfj33ifTMa5d+AAfAPTzhpuxISfiP7WC9ImqKofIXCIw5v el8mhWeTzP54dGa1Iv6A08FvPmXX5Vroid6kQZ4XO3D2ueXNOgTa+v6QXAEiTuyNKd /HPxiuZA1Inp/GSi2nLVXPCtN7RlPHgJXpNzH2G5P4XIHS5vACqr+jD/uoFpuYQ7zE uXUb6z4N5Ktig== From: Thadeu Lima de Souza Cascardo To: kernel-team@lists.ubuntu.com Subject: [SRU Focal 0/3] CVE-2022-27672 Date: Wed, 21 Jun 2023 17:22:40 -0300 Message-Id: <20230621202243.294012-1-cascardo@canonical.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" [Impact] A VM may force the CPU to go to idle and when it gets back from idle, it could leverage the RSB from a sibling thread to mount a speculative execution attack. [Backport] Simple conflicts and the placement of setting mitigate_smt_rsb. [Potential regression] It would affect VMs, specially when dealing with idleness. Tom Lendacky (3): x86/speculation: Identify processors vulnerable to SMT RSB predictions KVM: x86: Mitigate the cross-thread return address predictions bug Documentation/hw-vuln: Add documentation for Cross-Thread Return Predictions .../admin-guide/hw-vuln/cross-thread-rsb.rst | 92 +++++++++++++++++++ Documentation/admin-guide/hw-vuln/index.rst | 1 + arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/kernel/cpu/common.c | 9 +- arch/x86/kvm/x86.c | 44 ++++++--- 5 files changed, 134 insertions(+), 13 deletions(-) create mode 100644 Documentation/admin-guide/hw-vuln/cross-thread-rsb.rst Acked-by: Tim Gardner Acked-by: Cengiz Can Acked-by: Andrei Gherzan