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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 B5D2AC4360F for ; Thu, 4 Apr 2019 09:22:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 83F8720657 for ; Thu, 4 Apr 2019 09:22:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554369768; bh=x0yeo4z62a3cqIW1f8yCpm39MZ2Pda12HTGwZF7CAfM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FOw1lrSGWS4ywCE390Sd0mRNE3lzzqH8ZIbzwOleFVeW53f3vTE/e0bY0NE/2zrXc OexFH+vNgJu2wPEWEgpbS207AHICX+mgQHjiqrDTBDl2jy7MM7HJ0hH7fbR4ftCH4W 3Y4s9Ttyo3c2iKnfXdJgf1IcbjsSOafCoo0h3WqI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387943AbfDDJPq (ORCPT ); Thu, 4 Apr 2019 05:15:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:56774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387930AbfDDJPn (ORCPT ); Thu, 4 Apr 2019 05:15:43 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E246D20693; Thu, 4 Apr 2019 09:15:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554369342; bh=x0yeo4z62a3cqIW1f8yCpm39MZ2Pda12HTGwZF7CAfM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bvNpnyeeQ8AfQstQvEjlFCbAAFV36hXQgyW5gKeobgogyF+kkfSNV58NbBNh9nmcb hdeDu/EBk9gE9YOnc7FuGH8I/mxeOIgTdJ3ITq3duz16XwAPlhY51AlmbZCzwdPUHe Y55FvqZWTP6myjU/p49oxxif2/0t1vNKQTLcnDn8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ard Biesheuvel , Sai Praneeth Prakhya , AKASHI Takahiro , Alexander Graf , Bjorn Andersson , Borislav Petkov , Heinrich Schuchardt , Jeffrey Hugo , Lee Jones , Leif Lindholm , Linus Torvalds , Matt Fleming , Peter Jones , Peter Zijlstra , Thomas Gleixner , linux-efi@vger.kernel.org, Ingo Molnar , Sasha Levin Subject: [PATCH 5.0 175/246] efi/memattr: Dont bail on zero VA if it equals the regions PA Date: Thu, 4 Apr 2019 10:47:55 +0200 Message-Id: <20190404084625.305593989@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190404084619.236418459@linuxfoundation.org> References: <20190404084619.236418459@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 5.0-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 5de0fef0230f3c8d75cff450a71740a7bf2db866 ] The EFI memory attributes code cross-references the EFI memory map with the more granular EFI memory attributes table to ensure that they are in sync before applying the strict permissions to the regions it describes. Since we always install virtual mappings for the EFI runtime regions to which these strict permissions apply, we currently perform a sanity check on the EFI memory descriptor, and ensure that the EFI_MEMORY_RUNTIME bit is set, and that the virtual address has been assigned. However, in cases where a runtime region exists at physical address 0x0, and the virtual mapping equals the physical mapping, e.g., when running in mixed mode on x86, we encounter a memory descriptor with the runtime attribute and virtual address 0x0, and incorrectly draw the conclusion that a runtime region exists for which no virtual mapping was installed, and give up altogether. The consequence of this is that firmware mappings retain their read-write-execute permissions, making the system more vulnerable to attacks. So let's only bail if the virtual address of 0x0 has been assigned to a physical region that does not reside at address 0x0. Signed-off-by: Ard Biesheuvel Acked-by: Sai Praneeth Prakhya Cc: AKASHI Takahiro Cc: Alexander Graf Cc: Bjorn Andersson Cc: Borislav Petkov Cc: Heinrich Schuchardt Cc: Jeffrey Hugo Cc: Lee Jones Cc: Leif Lindholm Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Jones Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 10f0d2f577053 ("efi: Implement generic support for the Memory ...") Link: http://lkml.kernel.org/r/20190202094119.13230-4-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- drivers/firmware/efi/memattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/memattr.c b/drivers/firmware/efi/memattr.c index 8986757eafaf..aac972b056d9 100644 --- a/drivers/firmware/efi/memattr.c +++ b/drivers/firmware/efi/memattr.c @@ -94,7 +94,7 @@ static bool entry_is_valid(const efi_memory_desc_t *in, efi_memory_desc_t *out) if (!(md->attribute & EFI_MEMORY_RUNTIME)) continue; - if (md->virt_addr == 0) { + if (md->virt_addr == 0 && md->phys_addr != 0) { /* no virtual mapping has been installed by the stub */ break; } -- 2.19.1