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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 173F8CA9EA0 for ; Fri, 18 Oct 2019 16:11:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE881222D4 for ; Fri, 18 Oct 2019 16:11:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="FGaZKiG+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2443006AbfJRQLr (ORCPT ); Fri, 18 Oct 2019 12:11:47 -0400 Received: from mail-pf1-f201.google.com ([209.85.210.201]:36963 "EHLO mail-pf1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2502621AbfJRQL0 (ORCPT ); Fri, 18 Oct 2019 12:11:26 -0400 Received: by mail-pf1-f201.google.com with SMTP id p2so4979962pff.4 for ; Fri, 18 Oct 2019 09:11:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=OMV7GU+CS755gzThihulnjNw1pxqVtHrVsdKKTavPQY=; b=FGaZKiG+Ux25snyrOJrBiRd7RwQxjjLhUDr+StQE9m6QImfqUDq6yp6j+8Toagonr0 9TtbMLb3ay20pI9YbGG7nJzzM0vR4AyRpchI4t/ZYgICefWGJVsG/b/aJxIHIw5w9UV3 EIJDiPWiyVwP1F234VZ4D2+fA00WZK8lZRp8IvN7MdZJh8XNzU3kgbsv5o54oZ+iiZsI KghuQJd7vpAsaqImv6J86r3heyO3yrp6I8mcuRhzR5+TbYZJ39FxxZRefwS+iHZszAKS nursS3e3ycHoRmOFQHS1v/YDrqGB9JFjdDc8idnF+2J0IDA0s0+5SNkcUWwuinwq2OFT V+bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=OMV7GU+CS755gzThihulnjNw1pxqVtHrVsdKKTavPQY=; b=fNWj7cV/ZI0dkj13cb8ltsPxFvmU+WkaLyDP2xqJFt858Ir21209aOh4czi77mHK+z 954dFCVq7n5pWldVdeK8MiPlp3UmAqw9hNQwF0oJJwGpXsYihglxDAvzgoMR2W7GwgJD pk1lGQpbMnJHl6X5O8ejzzT3QH/JExNJ+fySjrfxvnFs6pcj+WTThc6pG8hlQ4Apf+Sp MPOTQYEHjgSsJOvAJnVlY1Y3RqqmzJFeAv4M0f/jDqON4VWQyzT0wlL/HeDWAejV/BtF EvuLOs7ZvEVsvGBIM/tNUqeea9WVjG05R4mLYz/siB4hLov9T2uzsBCB/anf7rMw4x15 KH0Q== X-Gm-Message-State: APjAAAUcu1WrVn7h4rJm8ZYo3Hnb5gYdZXZPQrgwIr9V1PO4cCNtA+1r OB6yXrNvCYxbWR0qrLyvdo9VWlUv1UfpWHn5aGc= X-Google-Smtp-Source: APXvYqycxw3zlWpqg/6yGEhb7CgOxW1rmJc0Y43aPOFAV6KRrpZHK92ZxBUvHsBpIOsv4SiMThIv0qzjvIsHF4JRnyI= X-Received: by 2002:a63:1904:: with SMTP id z4mr11066720pgl.413.1571415085386; Fri, 18 Oct 2019 09:11:25 -0700 (PDT) Date: Fri, 18 Oct 2019 09:10:29 -0700 In-Reply-To: <20191018161033.261971-1-samitolvanen@google.com> Message-Id: <20191018161033.261971-15-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> X-Mailer: git-send-email 2.23.0.866.gb869b98d4c-goog Subject: [PATCH 14/18] arm64: efi: restore x18 if it was corrupted From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Ard Biesheuvel Cc: Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If we detect a corrupted x18 and SCS is enabled, restore the register before jumping back to instrumented code. Signed-off-by: Sami Tolvanen --- arch/arm64/kernel/efi-rt-wrapper.S | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/efi-rt-wrapper.S b/arch/arm64/kernel/efi-rt-wrapper.S index 3fc71106cb2b..945744f16086 100644 --- a/arch/arm64/kernel/efi-rt-wrapper.S +++ b/arch/arm64/kernel/efi-rt-wrapper.S @@ -34,5 +34,10 @@ ENTRY(__efi_rt_asm_wrapper) ldp x29, x30, [sp], #32 b.ne 0f ret -0: b efi_handle_corrupted_x18 // tail call +0: +#ifdef CONFIG_SHADOW_CALL_STACK + /* Restore x18 before returning to instrumented code. */ + mov x18, x2 +#endif + b efi_handle_corrupted_x18 // tail call ENDPROC(__efi_rt_asm_wrapper) -- 2.23.0.866.gb869b98d4c-goog