From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 340A248CF2 for ; Mon, 11 Mar 2024 16:07:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710173266; cv=none; b=fiQd/kp09mY/O0TPBcAM0UHJv8a8sYrXujnkPUlgfjwOJcAyyu+woHosOay7viyKL3CGo9UY1eYu6XOndoJ157f0dNCyMsI2fso92WXYI0nBoD4j49P/l0iO5tJGBdy1V9iGBwCczCrEugiH3iphEbse7EmDYX8Fn2qeoWCJ2QQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710173266; c=relaxed/simple; bh=Vf1D/drG8dAvyzL6c7x+BSkJoHS3u5JICDtceL4dw9A=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=SzAMAtQywG0ABGXDneY1wO7UPhXTgXj9WjBIvjoN4ZaF7HHldnoMeE94quY0GslVLe6GELHtHHT4wq3EcJxU+wJwgDyeGuSN3Fif4Sy6BNF3+3OCOqKtXgBMvLE2uAHDoFR3KuTjsRK95pxEq1bI9YRDIWn3dpId8QhA6K6F9c0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=rlsr675w; arc=none smtp.client-ip=209.85.128.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="rlsr675w" Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-60a20c33f07so31537997b3.3 for ; Mon, 11 Mar 2024 09:07:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1710173264; x=1710778064; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=2I1JSNuwoRbdZ2LtvsNthD0wIWUGF8lxvDDDFf/XXwI=; b=rlsr675wTD8K9fKVfX0C+c2ZBmfS62NMrMMPie7N9kpiD4gCA6sYWfE8huejmOSGpY NzI9bv6Rcxt+b2WxmVbA/304d9zUdcpMU8iVQD2xPxOZNRyVG6roMe/WiX4eqBxsCebZ fhVmGeJ5fwe2dMeWURQgc4ioMI/yI843SqBi0QmdZTOkc8VMHLlHOmjnLGrktuQtMOk7 Miy/HzKvIIWoAMi0FK/J2zW7xtsb6oGrsM90qqf07HXn1cTP0ZLaJGw7wxqhWvPz2Go4 rLeMwohXSAMRT2ATZmJrTpS6BpX+K5xjrpEkRpXEOpYD3mAI9kd7KEnv5CAj5Xvnt3tu VrmQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1710173264; x=1710778064; 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=2I1JSNuwoRbdZ2LtvsNthD0wIWUGF8lxvDDDFf/XXwI=; b=aeEi7DbaFZoTX2PMS7/ATY+doOW+rdn559Z2kfqsr3cHelL6phC/Qux3BxzNmkE7HZ mG5kpSXhaj0CSuXgLNY+MS4rT11zPpZhUoiwEYxRKJw+lI6SHTOjj6UHuxVTDSVHEXwx 3SoRiWcXWKy+3PvY23/SeCGRKa+ef7YxtLTNB7ygY15noWT87nHbLS5DvvzuU6YuFrZD 8hmZTsgkvYCzHFlskxp751ezNdyU89QQv372utACwHOeSAWBxvqUxyQx8zQtbhcplpBD TadVkHRoA8t8PRxC/O+/n1W7GFb5sw1JGdF56s1xx64Yj+jygcj0IFiJ3PF11H1PNzcj az+A== X-Forwarded-Encrypted: i=1; AJvYcCWeV/PLotWBzVy/JxQzFe5PakAkyWOOYnX0f5VVf733F+rHuHoIbm80WMFDo1Whlk5GHD86uNMFvT+R6sTGvQZQktD973pdW6C7yM7X X-Gm-Message-State: AOJu0YyFrusWyvHhGwFMb8kuDOnrKZZpV34U1bq2zot2xDEWJsvdgsMz 0vSK0czN2QAEW3xI2uv+wftKBSZYzEd8v9a4uYMnpWniRyXSsozoanI3gSK4Y0wf7YoU6++X08h SzA== X-Google-Smtp-Source: AGHT+IH7ZTmuIMKrfes3mdxvE6B/9dW9KrRKc/OFzWnNh/fm0pvaaWzXshEZCqE+/gFWjTlOKiCD9fW9G2k= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a0d:d843:0:b0:60a:16ae:38ee with SMTP id a64-20020a0dd843000000b0060a16ae38eemr1797523ywe.3.1710173264289; Mon, 11 Mar 2024 09:07:44 -0700 (PDT) Date: Mon, 11 Mar 2024 16:07:42 +0000 In-Reply-To: <20240311134202.GQ86322@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <2024030251-CVE-2023-52514-c93d@gregkh> <20240311134202.GQ86322@google.com> Message-ID: Subject: Re: CVE-2023-52514: x86/reboot: VMCLEAR active VMCSes before emergency reboot From: Sean Christopherson To: Lee Jones Cc: Michal Hocko , cve@kernel.org, linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Juergen Gross , Andrew Cooper Content-Type: text/plain; charset="us-ascii" On Mon, Mar 11, 2024, Lee Jones wrote: > On Mon, 11 Mar 2024, Michal Hocko wrote: > > > On Sat 02-03-24 22:52:59, Greg KH wrote: > > > Description > > > =========== > > > > > > In the Linux kernel, the following vulnerability has been resolved: > > > > > > x86/reboot: VMCLEAR active VMCSes before emergency reboot > > > > > > VMCLEAR active VMCSes before any emergency reboot, not just if the kernel > > > may kexec into a new kernel after a crash. Per Intel's SDM, the VMX > > > architecture doesn't require the CPU to flush the VMCS cache on INIT. If > > > an emergency reboot doesn't RESET CPUs, cached VMCSes could theoretically > > > be kept and only be written back to memory after the new kernel is booted, > > > i.e. could effectively corrupt memory after reboot. > > > > > > Opportunistically remove the setting of the global pointer to NULL to make > > > checkpatch happy. > > > > > > The Linux kernel CVE team has assigned CVE-2023-52514 to this issue. > > > > I do not really see the security aspect of this fix. Guests systems > > shouldn't be able to trigger host reboot nor any untrusted entity should > > on the host either or this would be a serious security hole. And not just any reboot either, this only comes into play with something like `reboot -f`. Not to mention the impact of the bug is ridiculously theroetical (I didn't tag the patch for stable@ for a reason). > > Or am I missing something? > > Thanks for reporting. > > If Sean and/or Paolo agree, we can revoke the CVE for you. Please do.