From patchwork Wed May 12 14:50:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 438151 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 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 57699C43460 for ; Wed, 12 May 2021 16:30:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1863261288 for ; Wed, 12 May 2021 16:30:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238526AbhELQaZ (ORCPT ); Wed, 12 May 2021 12:30:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:40576 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236761AbhELQW7 (ORCPT ); Wed, 12 May 2021 12:22:59 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6CFC161CA3; Wed, 12 May 2021 15:47:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620834441; bh=Ou5baM93maEufZ1Up8/JrftESuCW3fNu8L4LME2rSRQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IkWyAPUH+SCxZ7ymOKKRr6g34VCWbehwbYK8iqkGOI82H4bWCWdgxrxhbXpFblvKC NTfuoQIY6pwhLTjk7fjd0O14Au5wnksDxlJfEv+wyJ6JUWZNpQXTDMvKH/Z8XT6MRD xS/f6C3v+mDdwdwtmGUKE9ILdB8eawKhtC4P0W0A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Brijesh Singh , Borislav Petkov , Tom Lendacky , Christophe Leroy , Sean Christopherson , Paolo Bonzini , Sasha Levin Subject: [PATCH 5.11 545/601] crypto: ccp: Detect and reject "invalid" addresses destined for PSP Date: Wed, 12 May 2021 16:50:22 +0200 Message-Id: <20210512144845.806956089@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144827.811958675@linuxfoundation.org> References: <20210512144827.811958675@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sean Christopherson [ Upstream commit 74c1f1366eb7714b8b211554f6c5cee315ff3fbc ] Explicitly reject using pointers that are not virt_to_phys() friendly as the source for SEV commands that are sent to the PSP. The PSP works with physical addresses, and __pa()/virt_to_phys() will not return the correct address in these cases, e.g. for a vmalloc'd pointer. At best, the bogus address will cause the command to fail, and at worst lead to system instability. While it's unlikely that callers will deliberately use a bad pointer 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 Cc: Christophe Leroy Fixes: 200664d5237f ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support") Signed-off-by: Sean Christopherson Message-Id: <20210406224952.4177376-3-seanjc@google.com> Reviewed-by: Brijesh Singh Acked-by: Tom Lendacky Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- 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 476113e12489..5b82ba7acc7c 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -149,6 +149,9 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) sev = psp->sev_data; + if (data && WARN_ON_ONCE(!virt_addr_valid(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;