From nobody Wed Apr 8 09:53:55 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E3CB9C38A2D for ; Tue, 25 Oct 2022 00:24:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229649AbiJYAYS (ORCPT ); Mon, 24 Oct 2022 20:24:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35020 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230336AbiJYAX2 (ORCPT ); Mon, 24 Oct 2022 20:23:28 -0400 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6760FCC827 for ; Mon, 24 Oct 2022 15:47:06 -0700 (PDT) Received: by mail-pf1-x44a.google.com with SMTP id cb7-20020a056a00430700b00561b86e0265so5287228pfb.13 for ; Mon, 24 Oct 2022 15:47:06 -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=VukVbYSP3OxCt2Aov1s0MXfB7/bJ8+HJOcG+qkdTnvVwyqSeEysxQibuYGQUZ3GZHb LQo/uctV2e8+FXtRqm1w3rlwt5gYx58CGxPrKqoR0yeaP8JfVnpR+nP6OXi9wVTzBBl9 AXKCdAMTHbE1mKJISj2iUiRLdw6PTThAzbg+o+a8LaRJc82/oAFNbu6ylNV6osG+qHp8 m5CycDkb++iVbaZA3ZFPyLWI3Z7GFGvKnDD+R/CQ2yo1ag9cs5xDXCH6qE743Q8S1mOq S/kRVHwrJWzq6x1OLj+u3ATxd/9s8S1RZ3/NisX1JirkpZVY76wYTLHgmfhH45U6kaxx 3HAQ== 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=Bul4N3EFuhyyXyM0v7Gbm1d9wFFgTUVjuIKWIHKOuppIg2F7Bz4nkx+J5o4POFYv3l HYnOtvcWFn3OKCabFBUFiqc2aTg8cydtGotepVr3ywQdg8v8idvrP6oOOo/Bf4+OD1Hx FqFoHRM0cLfN7GPcPnsKqrYMkS7t0vLU2Yqay4avMQ9195DYH4f/HON/Ev13b+HkGzEc 936fs5uRUjEVUHI0VHmTPG99aj8ZZ07YyDx0YtJYwCadf502dnuizn04jYhuI1mV9iz6 blKSsvjcEgzARRO85DZfwQ322W2OovDd5zV3qvFuqc5yUrXsu9MjSnjDuSiQ99N9eE6L H0tw== X-Gm-Message-State: ACrzQf09eT6O4CMoDHFdqin1H9KQ/hzLVQprOQjK28iSmSaKlYSpPgjj yjX3a+Rw/cjFPLv+x7DjALe8zPxdu0iDUV51U+aE0+D/Il00jy9enBD6RpdVHjSkrnp7Yn0HEWt 3Zcqgx9EsHJeTIl/NyLftAJjZ2ZoHM4BKFFF1VuwwogUF0qLKIQQghOcMN2UepqRMwxq9mr55J9 wtW/Hipn4= X-Google-Smtp-Source: AMsMyM5bE+DXOug7SxNNmWpiYtjeZTIN+bvNMw2JNHpElWmuN0VO5+l1lT7ilIZJh0kInbRZL3+ELwZyoHO3AcbztQ== X-Received: from dionnaglaze.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2ee6]) (user=dionnaglaze job=sendgmr) by 2002:a17:90a:4811:b0:20a:fee1:8f69 with SMTP id a17-20020a17090a481100b0020afee18f69mr4038806pjh.0.1666651625380; Mon, 24 Oct 2022 15:47:05 -0700 (PDT) Date: Mon, 24 Oct 2022 22:46:56 +0000 In-Reply-To: <20221024224657.2917482-1-dionnaglaze@google.com> Mime-Version: 1.0 References: <20221024224657.2917482-1-dionnaglaze@google.com> X-Mailer: git-send-email 2.38.0.135.g90850a2211-goog Message-ID: <20221024224657.2917482-4-dionnaglaze@google.com> Subject: [PATCH v4 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 Reviewed-by: Tom Lendacky --- 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/se= v-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, u= 64 seqno, int version, u8 =20 static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_co= de, 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; =20 @@ -322,9 +321,7 @@ static int handle_guest_request(struct snp_guest_dev *s= np_dev, u64 exit_code, in return rc; =20 /* Call firmware to process the request */ - rc =3D snp_issue_guest_request(exit_code, &snp_dev->input, &err); - if (fw_err) - *fw_err =3D err; + rc =3D snp_issue_guest_request(exit_code, &snp_dev->input, exitinfo2); =20 if (rc) return rc; --=20 2.38.0.135.g90850a2211-goog