From patchwork Tue Feb 7 22:48:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 13132176 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5387DC636CD for ; Tue, 7 Feb 2023 22:49:37 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pPWm1-0003iB-Sc; Tue, 07 Feb 2023 17:49:13 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pPWlz-0003hK-OS for qemu-devel@nongnu.org; Tue, 07 Feb 2023 17:49:11 -0500 Received: from ams.source.kernel.org ([145.40.68.75]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pPWly-00027s-3G for qemu-devel@nongnu.org; Tue, 07 Feb 2023 17:49:11 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B8836B81B35; Tue, 7 Feb 2023 22:49:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70212C433D2; Tue, 7 Feb 2023 22:49:06 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="mB4x1036" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1675810145; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=mmF5cmjJqKs/c2ujhOJHw4MyozFGKJOoSzRlAe/Wo1A=; b=mB4x1036U9fiG1PXe4HIuZ9VGkmQAenajjVdklk3V7O3LZvpOrgpcQtYeronah9oPCv4VE /XXLPyzbY1004vpGf6sh3uiUpdhJlKDbyyNDF2NV/gP4y5CsE/Ex6+mPupTHeWytmyRFEX HvTHmwgW65EvYUh91EzLU6YBP3TDKc8= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 1a94f89e (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Tue, 7 Feb 2023 22:49:05 +0000 (UTC) From: "Jason A. Donenfeld" To: mst@redhat.com, qemu-devel@nongnu.org Cc: "Jason A. Donenfeld" , Dov Murik , Tom Lendacky , Gerd Hoffmann , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Paolo Bonzini , Richard Henderson Subject: [PATCH 2/2] x86: don't append setup_data to cmdline for SEV guests Date: Tue, 7 Feb 2023 19:48:47 -0300 Message-Id: <20230207224847.94429-3-Jason@zx2c4.com> In-Reply-To: <20230207224847.94429-1-Jason@zx2c4.com> References: <20230207224847.94429-1-Jason@zx2c4.com> MIME-Version: 1.0 Received-SPF: pass client-ip=145.40.68.75; envelope-from=SRS0=KxRu=6D=zx2c4.com=Jason@kernel.org; helo=ams.source.kernel.org X-Spam_score_int: -67 X-Spam_score: -6.8 X-Spam_bar: ------ X-Spam_report: (-6.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Dov Murik Modifying the cmdline by appending setup_data breaks measured boot with SEV and OVMF, and possibly signed boot. Previously this was disabled when appending to the kernel image, but with eac7a7791bb6 ("x86: don't let decompressed kernel image clobber setup_data"), this was changed to the cmdline file instead, with the sev_enabled() check left out. Fixes: eac7a7791bb6 ("x86: don't let decompressed kernel image clobber setup_data") Reported-by: Tom Lendacky Signed-off-by: Dov Murik Signed-off-by: Jason A. Donenfeld --- hw/i386/x86.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/i386/x86.c b/hw/i386/x86.c index c6d7bf6db2..80a1678acd 100644 --- a/hw/i386/x86.c +++ b/hw/i386/x86.c @@ -1079,7 +1079,7 @@ void x86_load_linux(X86MachineState *x86ms, fclose(f); /* append dtb to kernel */ - if (dtb_filename) { + if (dtb_filename && !sev_enabled()) { if (protocol < 0x209) { fprintf(stderr, "qemu: Linux kernel too old to load a dtb\n"); exit(1); @@ -1103,7 +1103,7 @@ void x86_load_linux(X86MachineState *x86ms, load_image_size(dtb_filename, setup_data->data, dtb_size); } - if (!legacy_no_rng_seed && protocol >= 0x209) { + if (!legacy_no_rng_seed && protocol >= 0x209 && !sev_enabled()) { setup_data_offset = cmdline_size; cmdline_size += sizeof(SetupData) + RNG_SEED_LENGTH; kernel_cmdline = g_realloc(kernel_cmdline, cmdline_size);