QEMU version 2.12.0 released
24 Apr 2018
This release contains 2700+ commits from 204 authors.
* Spectre/Meltdown mitigation support for x86/pseries/s390 guests.
* Better IPMI support for Platform Events and SEL logging in internal BMC emulation
* SMBIOS support for “OEM Strings”, which can be used for automating guest image activation without relying on network-based querying
[…]A previous post detailed how QEMU/KVM might be affected by Spectre/Meltdown attacks, and what the plan was to mitigate them in QEMU 2.11.1 (and eventually QEMU 2.12). QEMU 2.11.1 is now available, and contains the aforementioned mitigation functionality for x86 guests, along with additional mitigation functionality for pseries and s390x guests (ARM guests do not currently require additional QEMU patches). However, enabling this functionality requires additional configuration beyond just updating QEMU, which we want to address with this post.[…]
More on QEMU and Spectre/Meltdown:
C++ Developer Guidance for Speculative Execution Side Channels
Matt Miller Colin Robertson Mike B
This article contains guidance for developers to assist with identifying and mitigating speculative execution side channel hardware vulnerabilities in C++ software. These vulnerabilities can disclose sensitive information across trust boundaries and can affect software that runs on processors that support speculative, out-of-order execution of instructions. This class of vulnerabilities was first described in January, 2018 and additional background and guidance can be found in Microsoft’s security advisory. The guidance provided by this article is related to the class of vulnerabilities represented by CVE-2017-5753, also known as Spectre variant 1. This hardware vulnerability class is related to side channels that can arise due to speculative execution that occurs as a result of a conditional branch misprediction. The Visual C++ compiler in Visual Studio 2017 (starting with version 15.5.5) includes support for the /Qspectre switch provides a compile-time mitigation for a limited set of potentially vulnerable coding patterns related to CVE-2017-5753. The documentation for the /Qspectre flag provides more information on its effects and usage.[…]
[…]An accessible introduction to speculative execution side channel vulnerabilities can be found in the presentation titled The Case of Spectre and Meltdown by one of the research teams that discovered these issues.[…]
A few new Spectre/Meltdown-related things in the news:
This updated alert is a follow-up to the updated alert titled ICS-ALERT-18-011-01 Meltdown and Spectre Vulnerabilities (Update F) that was published March 1, 2018, on the NCCIC/ICS-CERT website.
Spectre Mitigation Update
Today, AMD is providing updates regarding our recommended mitigations for Google Project Zero (GPZ) Variant 2 (Spectre) for Microsoft Windows users. These mitigations require a combination of processor microcode updates from our OEM and motherboard partners, as well as running the current and fully up-to-date version of Windows. For Linux users, AMD recommended mitigations for GPZ Variant 2 were made available to our Linux partners and have been released to distribution earlier this year.[…]