From patchwork Fri Apr 2 23:36:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 12181749 X-Patchwork-Delegate: herbert@gondor.apana.org.au 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 A2811C43460 for ; Fri, 2 Apr 2021 23:37:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 781EE61185 for ; Fri, 2 Apr 2021 23:37:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234821AbhDBXhT (ORCPT ); Fri, 2 Apr 2021 19:37:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235341AbhDBXhT (ORCPT ); Fri, 2 Apr 2021 19:37:19 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59320C061797 for ; Fri, 2 Apr 2021 16:37:17 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id w7so10869239ybq.4 for ; Fri, 02 Apr 2021 16:37:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=0LM6xcoLFCRsb/RrOWErJVCC7SaCW1PJNWp8wUkAbs8=; b=Pg0Typ4Q1+Mnkw5PV9gEyPGAg3vVXc9K2xcboUDafknVQoB+1YdTsZM2Aj4t6mdJKi iS0cldfS2nCihyYUUwduL8D/bT+cRUvnt+2TYTjiFhFrf3VhvctCDCTUEUPDs2uvJaI6 RjrRkq970wcGJqChk4YEI+vmURNdKbKrMNVjQKsUtv1gTAYDetRarMh0fM0TcJ+QaRCL yvYcukJGhDP/++YhQfxX+JHjK8SO6DCiMhsL6qv/CCobRPCCwyGQDf9/6GKyuE9s0JuG 9uBCO2nOVBqEywUBq1QO2P0PModU5TOZgI1NbZwmMi4LSJpaG+sMIdVF8Evio7uTRp2w s+lw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=0LM6xcoLFCRsb/RrOWErJVCC7SaCW1PJNWp8wUkAbs8=; b=fIO0LD/DzMJAsjlHQ06oklJ9pN0TGxXOwzzS/Z64OU+ATARu58BJnWYnLcAlqUmFEO t/emKFxxoTmaWx8hEs1SLL8z3D38aIt2wh9aVW7nHKrsQUeB8SKeGZuxRK1V287Nl+ng 9Z4/6oF8nV0CTCuSK3Fkadj9Qirk+T+pJe0cgPmiz12MacQQ0GijSOOPGgVL8/MCes// d2QyI4REM0JguRGVr1ryoTixLq66K0BevNRo7OBm7hissLYsnrZkp3g0bJ+Dlx09OcAZ OhndSBtGI8aMsBn7ktEq9w4HClSeHasY7OhQKtrCYbxCfu/pIMqYZZrr6VSHAbTkTGvv lQvA== X-Gm-Message-State: AOAM532R0nv7lIfv9jg2BkpE943DBV9wsNTXzPqy4ewkhhDwnGDUrEIn RSOEfpe91OD213w8LZaeq+0ntbPMdCM= X-Google-Smtp-Source: ABdhPJwqG3jIPZ0z+TizSalVeZBrtmUZjK9lKQGsJb/Q2mt+C2P4+FWk3plTbgpam0rOqej5aloGscqXgnQ= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:f:10:24a7:3342:da61:f6aa]) (user=seanjc job=sendgmr) by 2002:a25:144:: with SMTP id 65mr19595306ybb.394.1617406636576; Fri, 02 Apr 2021 16:37:16 -0700 (PDT) Reply-To: Sean Christopherson Date: Fri, 2 Apr 2021 16:36:58 -0700 In-Reply-To: <20210402233702.3291792-1-seanjc@google.com> Message-Id: <20210402233702.3291792-2-seanjc@google.com> Mime-Version: 1.0 References: <20210402233702.3291792-1-seanjc@google.com> X-Mailer: git-send-email 2.31.0.208.g409f899ff0-goog Subject: [PATCH 1/5] crypto: ccp: Detect and reject vmalloc addresses destined for PSP From: Sean Christopherson To: Paolo Bonzini , Brijesh Singh , Tom Lendacky , John Allen Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Borislav Petkov Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org Explicitly reject vmalloc'd data as the source for SEV commands that are sent to the PSP. The PSP works with physical addresses, and __pa() will not return the correct address for a vmalloc'd pionter, which at best will cause the command to fail, and at worst lead to system instability. While it's unlikely that callers will deliberately use vmalloc() for SEV buffers, a caller can easily use a vmalloc'd pointer unknowingly when running with CONFIG_VMAP_STACK=y as it's not obvious that putting the command buffers on the stack would be bad. The command buffers are relative small and easily fit on the stack, and the APIs to do not document that the incoming pointer must be a physically contiguous, __pa() friendly pointer. Cc: Brijesh Singh Cc: Borislav Petkov Cc: Tom Lendacky Fixes: 200664d5237f ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support") Signed-off-by: Sean Christopherson --- drivers/crypto/ccp/sev-dev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index cb9b4c4e371e..6556d220713b 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -150,6 +150,9 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) sev = psp->sev_data; + if (data && WARN_ON_ONCE(is_vmalloc_addr(data))) + return -EINVAL; + /* Get the physical address of the command buffer */ phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0; phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;