From patchwork Fri Oct 21 16:59:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dionna Amalie Glaze X-Patchwork-Id: 6885 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:4242:0:0:0:0:0 with SMTP id s2csp808272wrr; Fri, 21 Oct 2022 10:07:05 -0700 (PDT) X-Google-Smtp-Source: AMsMyM5J0VX1Tzx7u8HW1244Xi1WCRdeR+VrwoEjHfVvFu4ggcUQqCUe36HYVRfWiQsbeppDws2J X-Received: by 2002:a17:90a:990d:b0:212:d772:1ab4 with SMTP id b13-20020a17090a990d00b00212d7721ab4mr2441168pjp.184.1666372025007; Fri, 21 Oct 2022 10:07:05 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1666372025; cv=none; d=google.com; s=arc-20160816; b=sXr85zlnx6xLXF1oxZt+Ex1qs9ES7LPt6o6DQbczVguNEzDEUyuy2WRwgFHt02v2fZ 7mfFIaExbp2LbBH7SekYX1E9qBxkwom2/BhiiNgICgRG8bCcKNmffR1A6y+j1eiDnl1q nG3BJjtx8kOMX5xbmDnPOT6W4ku+GkZ3Xp9PbjYju4nIzmiZU+f9pcj7BEae3OsoGnZG 2w7Nl7m8JZVUG8vfEliVCc2gc21Paxhw8WfzEpl52TzLcmlo49uBsdvYZgp4GfU5hYNf RLajjMbkicIpO5nyZXZZbJ1XWXgA89Ac/QzDV/Qdbv/6d3HVD60xsvDAlHD9P2uLozgH 1DlQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:dkim-signature; bh=t50s+W2sjRzmfaqPHM8BWoKuylKuq2NrCynpVhPS9Gk=; b=KQIZITsq2emcLALSQlCSZTW2CYmDHoSvCyrOGfNVbONyZpmHkP7WB7qG4UrGqm2SaN D0zvhpvrGJJhy59dwzq0PzFI9ajPGK/6JO2z88UWBN81vk0NZo4d7vMybwEPOdepqgy1 o7hFRyxjt5ecikDG5elvc9SfZD1UeHGP8liIUMF9G2aTl5DlEDlU258JdoOBeLYnellf i8JY3ObUyWcHxdInq92DhPnI/j2tc7PViAuAX3lIYc7VuYyfoE1X0wbaQOwPoCfOPxTs qzL5t3zQWNvXLjqKdNiEcgNJyGFqB3FRBmwhBy2S0RSXupdVft/J4gBlTWo6hXybtLUJ bHpQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20210112 header.b=D9gJIDip; 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=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id y15-20020a655b0f000000b004613324b2f8si26244987pgq.747.2022.10.21.10.06.51; Fri, 21 Oct 2022 10:07:04 -0700 (PDT) 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=@google.com header.s=20210112 header.b=D9gJIDip; 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=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229995AbiJURAQ (ORCPT + 99 others); Fri, 21 Oct 2022 13:00:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229975AbiJURAE (ORCPT ); Fri, 21 Oct 2022 13:00:04 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 505AE558F4 for ; Fri, 21 Oct 2022 09:59:54 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id o17-20020a170902d4d100b0018552c4f4bcso1996722plg.13 for ; Fri, 21 Oct 2022 09:59:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=t50s+W2sjRzmfaqPHM8BWoKuylKuq2NrCynpVhPS9Gk=; b=D9gJIDipIbDmmnhQPtT5HvABc6SjejzqBT5yiNYUXkric3SrAQON1oJaySHETkWhRF PX+KXKZ8JyA88v5tE4EMTFFJ56/REmpBVnlywvFa42c+E/x0SheZzLwiWE2jhqQ+ldz/ enUDwkgtlYTXMR/moT5KYh1uSh5HqP4f5+krbjx7kwfdJGvD8LMPgse7XWYz84ecIap3 Gm1jQw7vlBv3YOHYsL+3u0MKUTb4Wr9w9Kl/hnfs7pZzn9geE9pgrSyKDnTu2C10Z9vr 7m2WMljG5b0dphDbKtqSD/H50W5Ti5sTtcWvFUQJcn/fzKGTVFPvaTkkgPtnH78qD43g NoSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=t50s+W2sjRzmfaqPHM8BWoKuylKuq2NrCynpVhPS9Gk=; b=Z84mbLYoaaHWZQaHkhTVpLqYOUqgFTVFYMRIs1sCb0pCFGSpKBQcN0cwBHylTIedwG tnSF81C+Dn6LD/iPXM1v/8ig6D9uBMTLaTkaw5y+Z6JWCj6C44N/SHo7sfjCH2SPJ4Gx QunKNEQFhFD5+i+vjXGPGbbxkut/rnlA9zhtQxCP8jjeIYNWBvEy9Qnn/no6NgOysimm A9Z6XcD44midn81meKuoISjBAQaEDpjmJCzBzG/UTes7w0BCmFQ7+kVL4tZwVAnf0qh6 r074J8pKTH5jZHwxmOLNl6E5AqWFtmH1p7oon0Li9R5g5dEkyUpihODhXZ8jJNYQr0dy poxg== X-Gm-Message-State: ACrzQf0M3EsiZ/lMmAUi9oIbTQ0JPTdLdbtpIrDo0yIkzTuTydrXgP7o b7br5YS2kDVfWZFNp7odBRR1h0WHOfCGNcLPlV4DJhOnotSmb3YowWZx4Pp6S+umrLYc8/bP6s2 arAw2G25RZRhUXaXXXP44HF8eJxSx8lwabJuzK6PqseLRyCBfI8Zjxpftzgcgr+xnr7u+br/T3K 6GdCBLXkQ= X-Received: from dionnaglaze.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2ee6]) (user=dionnaglaze job=sendgmr) by 2002:a17:902:e191:b0:181:b25e:9c17 with SMTP id y17-20020a170902e19100b00181b25e9c17mr20441665pla.57.1666371593958; Fri, 21 Oct 2022 09:59:53 -0700 (PDT) Date: Fri, 21 Oct 2022 16:59:42 +0000 In-Reply-To: <20221021165943.1968044-1-dionnaglaze@google.com> Mime-Version: 1.0 References: <20221021165943.1968044-1-dionnaglaze@google.com> X-Mailer: git-send-email 2.38.0.135.g90850a2211-goog Message-ID: <20221021165943.1968044-4-dionnaglaze@google.com> Subject: [PATCH v3 3/4] virt/coco/sev-guest: Remove err in handle_guest_request From: Dionna Glaze To: linux-kernel@vger.kernel.org, x86@kernel.org Cc: Dionna Glaze , Tom Lendacky , Paolo Bonzini , Joerg Roedel , Peter Gonda , Thomas Gleixner , Dave Hansen X-Spam-Status: No, score=-9.6 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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?1747317712508743769?= X-GMAIL-MSGID: =?utf-8?q?1747317712508743769?= The err variable may not be set in the call to snp_issue_guest_request, yet it is unconditionally written back to fw_err if fw_err is non-null. This is undefined behavior, and currently returns uninitialized kernel stack memory to user space. The fw_err argument is better to just pass through to snp_issue_guest_request, so we do that. Since the issue_request's signature has changed fw_err to exitinfo2, we change the argument name here. Cc: Tom Lendacky Cc: Paolo Bonzini Cc: Joerg Roedel Cc: Peter Gonda Cc: Thomas Gleixner Cc: Dave Hansen Fixes: fce96cf04430 ("virt: Add SEV-SNP guest driver") Signed-off-by: Dionna Glaze --- drivers/virt/coco/sev-guest/sev-guest.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index f422f9c58ba7..0508c2f46f6b 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -303,9 +303,8 @@ static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, int msg_ver, u8 type, void *req_buf, size_t req_sz, void *resp_buf, - u32 resp_sz, __u64 *fw_err) + u32 resp_sz, __u64 *exitinfo2) { - unsigned long err; u64 seqno; int rc; @@ -322,9 +321,7 @@ static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, in return rc; /* Call firmware to process the request */ - rc = snp_issue_guest_request(exit_code, &snp_dev->input, &err); - if (fw_err) - *fw_err = err; + rc = snp_issue_guest_request(exit_code, &snp_dev->input, exitinfo2); if (rc) return rc;