Received: by 2002:a05:6358:16cc:b0:ea:6187:17c9 with SMTP id r12csp8471832rwl; Sat, 31 Dec 2022 06:23:58 -0800 (PST) X-Google-Smtp-Source: AMrXdXvUWkoeS2k+FIQWiWAfbm0JKGFJqj2aQiC42g8fgIZ/+3v+v7roTPmwc3WCfJr1WJXyWywi X-Received: by 2002:a05:6a00:1c9f:b0:577:8c7e:7489 with SMTP id y31-20020a056a001c9f00b005778c7e7489mr38898428pfw.10.1672496638276; Sat, 31 Dec 2022 06:23:58 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1672496638; cv=none; d=google.com; s=arc-20160816; b=Z9fG98f6VJ0Ufyfr5+ZinH43M43ChhNEXRpuAmmCSMMJcpgDKzJp2ANuiXl6xTPjMQ gGy08cgs0hLgzcWLZLg+qwcnoy0c84gdS1rpeQQmUVoPODpPWANIoR95YL1tX4+cFLP4 21df0uFyOr+at7xOoNyWAQb9dLduDkz3LKPpy1UawQ4eQ2IzQdFYA0skHAqcVwSScRVT awfVf4+vLBwYCFXagr26jCP7DIOWoKUt3rFhHVethheuejMqyY/H+9aqIJJA6sSZnpuS SPHuHJ1UGAtQU/YBRrCrm0OSSCujs26G3RSZs+7R9P8Oo1lM2gePcwOf5Eq9qOoaj0Pl tt/w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=m7rCTpk9c3/hvAowOtgf/iURb5jKAxrFcYb/Bg6gYRQ=; b=ShDhmYAtYCKHtcht3Q0hKLnS7S2/w2yLknQQgrj/Hpvde+A64FnRpT2+uNfqRUYdTS Cc5wBD8BCSaN4EPFTxye5hutBCrkVdbfp7662JPTrIiE23wXj4lGkagJzkzc1Zz+gODX 1zX4JiqEVQnPLxNPMl7SO3yv1d3E/URFlTz6zkpvgt4bQ01jJ0Of5NkW4b0PNzPctX3M pkoRT6vkVvqf1yLTqXABINSxYCaOY2Wg7dNP5yAxmZ8PfntidqcpEeU0ojKJMvWTWYkL 9RnAGkBIICzznQpGNmlpmurwoWA8F33H2dStC2yXuueUZEXS5lDb86vN74XTn6l2/c1D Fp4Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@alien8.de header.s=dkim header.b=Tjc0FU6R; 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=NONE sp=NONE dis=NONE) header.from=alien8.de Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id j14-20020a62e90e000000b005775394c99fsi23763033pfh.52.2022.12.31.06.23.49; Sat, 31 Dec 2022 06:23:58 -0800 (PST) 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=@alien8.de header.s=dkim header.b=Tjc0FU6R; 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=NONE sp=NONE dis=NONE) header.from=alien8.de Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229755AbiLaNlD (ORCPT + 63 others); Sat, 31 Dec 2022 08:41:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229484AbiLaNlC (ORCPT ); Sat, 31 Dec 2022 08:41:02 -0500 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2B902E9 for ; Sat, 31 Dec 2022 05:41:01 -0800 (PST) Received: from zn.tnic (p5de8e9fe.dip0.t-ipconnect.de [93.232.233.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 4F1041EC0493; Sat, 31 Dec 2022 14:41:00 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1672494060; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=m7rCTpk9c3/hvAowOtgf/iURb5jKAxrFcYb/Bg6gYRQ=; b=Tjc0FU6RHjhOvvCJfJrEuEBEOAExLE5buF0lpG62t4mKcXRx7eZHjNH6zMgr4zuhVmlB+3 HQkg3c3WFNG6YBQ17h7XTBLpD0yE3yfWEWpHL/7tl3cQtaMdI7McVw7GcdBNba16CYno0d NxAQ+L/Vk4LcN4m0LEUuo4cp93aDJJI= Date: Sat, 31 Dec 2022 14:40:59 +0100 From: Borislav Petkov To: "H. Peter Anvin" Cc: "Jason A. Donenfeld" , pbonzini@redhat.com, ebiggers@kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, qemu-devel@nongnu.org, ardb@kernel.org, kraxel@redhat.com, philmd@linaro.org Subject: Re: [PATCH qemu] x86: don't let decompressed kernel image clobber setup_data Message-ID: References: <46466e54-25c3-3194-8546-a57cd4a80d9d@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <46466e54-25c3-3194-8546-a57cd4a80d9d@zytor.com> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS 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 On Fri, Dec 30, 2022 at 05:06:55PM -0800, H. Peter Anvin wrote: > This needs to be something like: > > kernel_add_identity_map(sd_addr, sd_addr + sizeof(*sd)); > kernel_add_identity_map(sd_addr + sizeof(*sd), > sd_addr + sizeof(*sd) + sd->len); It still #PFs with that: (gdb) bt #0 0xffffffff84738576 in native_halt () at ./arch/x86/include/asm/irqflags.h:57 #1 halt () at ./arch/x86/include/asm/irqflags.h:98 #2 early_fixup_exception (regs=regs@entry=0xffffffff84007dc8, trapnr=trapnr@entry=14) at arch/x86/mm/extable.c:340 #3 0xffffffff846ff465 in do_early_exception (regs=0xffffffff84007dc8, trapnr=14) at arch/x86/kernel/head64.c:424 #4 0xffffffff846ff14f in early_idt_handler_common () at arch/x86/kernel/head_64.S:483 #5 0xc149f9894908788d in ?? () #6 0xffffffffff2003fc in ?? () #7 0x0000000000000010 in fixed_percpu_data () #8 0xdffffc0000000000 in ?? () #9 0xffffffff84007ea8 in init_thread_union () #10 0xffffffffff20088d in ?? () #11 0x0000000000000000 in ?? () /me goes to dig more. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette