From patchwork Thu Dec 15 12:38:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evgeniy Baskov X-Patchwork-Id: 33625 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:e747:0:0:0:0:0 with SMTP id c7csp327759wrn; Thu, 15 Dec 2022 04:43:30 -0800 (PST) X-Google-Smtp-Source: AA0mqf79Sr+QqINmsRzgGVzt1R+3BoFVmU2EimxStiof9Z/XeftfkIHdeSyjqFH/5/8FkT0440yi X-Received: by 2002:a17:906:8257:b0:7c1:5098:907f with SMTP id f23-20020a170906825700b007c15098907fmr17002138ejx.61.1671108210538; Thu, 15 Dec 2022 04:43:30 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1671108210; cv=none; d=google.com; s=arc-20160816; b=fTcohW9T61Z+V6GgJKvl5MvgjboQQr59NeDKpA93Nrrs0pJPY7St6SWUeWiVMQVhlr B3IwIWh7YvNTJqNEmLw3lQLXN2mHIngC3Uu4DPbA/VLMihGlizxh96rmSQfUgZGS5AuT CAMjghydSJK+BY2GNqNBJRPzCx25Tc7V5U9c/auCIAVlTARJc/CU22+yHRXgoz3KJHW9 t0IWrUQQ6/VhsnBi2BFDQ5CU+GHpqn3bMH7QGkrAxFECUhXGwBEYwF6BwQuNmY4M6tpE rIiYIXDHVk4/Tp3cZFAozGzU2Umv8FmTtJQStjwUIz4y3r21k3ODJJ6qb1OZbD9vFlhe a5Vw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:dkim-filter; bh=KkRKm6qcAmh0kiXQ21qOF8qFcABzU2w96OZgSYkHTXk=; b=f/Cgd9Gf+Nwc/aEmzB0t84OETqjrdYuSp56MdwdPA3oyLeUeIZFbpGzWODGWch+72k shmaH95zOSq1B4GUO2vksNKcGCWl9V1vFo3Cs7r2UH9g1iCoxFgZlJIFRfOJPtTiUDHe 59EqT79N6fPNV5EhRUwbbVbK/25PUAmmiSmR91wg6ZPbnCKY9XrW21pj0iRZYfzp2JJ9 74/kS2Scbn38sGKPfZ8JOMK0AjMKkT4nBid7GufSvPXL2TJHJuiCzMe//J6TeG5L5Y3X 6hnSSYs7IvT2XeaTlSSwfMaLbmu8/dqmht9CcWM7rjlsKhS6SgBFRotwNVgJ4pnAdyrN O8PQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@ispras.ru header.s=default header.b=obfol3CW; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ispras.ru Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id hd12-20020a170907968c00b007ad855bc09csi15139828ejc.595.2022.12.15.04.43.07; Thu, 15 Dec 2022 04:43:30 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@ispras.ru header.s=default header.b=obfol3CW; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ispras.ru Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229626AbiLOMlq (ORCPT + 99 others); Thu, 15 Dec 2022 07:41:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229905AbiLOMlY (ORCPT ); Thu, 15 Dec 2022 07:41:24 -0500 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CAD0D27916; Thu, 15 Dec 2022 04:40:24 -0800 (PST) Received: from localhost.localdomain (unknown [83.149.199.65]) by mail.ispras.ru (Postfix) with ESMTPSA id 3C6D740737AF; Thu, 15 Dec 2022 12:40:23 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru 3C6D740737AF DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1671108023; bh=KkRKm6qcAmh0kiXQ21qOF8qFcABzU2w96OZgSYkHTXk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=obfol3CWp8LzXplKHkyHUZG/d7EfhBPFxgNTXiq/+9N8zDYn8ZUrazpcQ4bVXwJ2r K84oqYuP8j8keBSAxnJ3M0/tyucNLJbN6LEyFF9wedck8+HdFNuJb30hP0EVXy+rmU Mj7tXclEFv5gACAMJ1Rgv50xHd23feclvEs1SYc0= From: Evgeniy Baskov To: Ard Biesheuvel Cc: Evgeniy Baskov , Borislav Petkov , Andy Lutomirski , Dave Hansen , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Alexey Khoroshilov , Peter Jones , "Limonciello, Mario" , joeyli , lvc-project@linuxtesting.org, x86@kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v4 09/26] x86/boot: Remove mapping from page fault handler Date: Thu, 15 Dec 2022 15:38:00 +0300 Message-Id: X-Mailer: git-send-email 2.37.4 In-Reply-To: References: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1752283963084720402?= X-GMAIL-MSGID: =?utf-8?q?1752283963084720402?= After every implicit mapping is removed, this code is no longer needed. Remove memory mapping from page fault handler to ensure that there are no hidden invalid memory accesses. Tested-by: Mario Limonciello Tested-by: Peter Jones Signed-off-by: Evgeniy Baskov Reviewed-by: Ard Biesheuvel --- arch/x86/boot/compressed/ident_map_64.c | 26 ++++++++++--------------- 1 file changed, 10 insertions(+), 16 deletions(-) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index fec795a4ce23..ba5108c58a4e 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -386,27 +386,21 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) { unsigned long address = native_read_cr2(); unsigned long end; - bool ghcb_fault; + char *msg; - ghcb_fault = sev_es_check_ghcb_fault(address); + if (sev_es_check_ghcb_fault(address)) + msg = "Page-fault on GHCB page:"; + else + msg = "Unexpected page-fault:"; address &= PMD_MASK; end = address + PMD_SIZE; /* - * Check for unexpected error codes. Unexpected are: - * - Faults on present pages - * - User faults - * - Reserved bits set - */ - if (error_code & (X86_PF_PROT | X86_PF_USER | X86_PF_RSVD)) - do_pf_error("Unexpected page-fault:", error_code, address, regs->ip); - else if (ghcb_fault) - do_pf_error("Page-fault on GHCB page:", error_code, address, regs->ip); - - /* - * Error code is sane - now identity map the 2M region around - * the faulting address. + * Since all memory allocations are made explicit + * now, every page fault at this stage is an + * error and the error handler is there only + * for debug purposes. */ - kernel_add_identity_map(address, end, MAP_WRITE); + do_pf_error(msg, error_code, address, regs->ip); }