From 4e37e21f6e71752fb69c27ab9f1417a5d19ebedb Mon Sep 17 00:00:00 2001 From: Ian Jackson Date: Tue, 9 Mar 2021 15:00:47 +0000 Subject: [PATCH 1/2] SUPPORT.md: Document speculative attacks status of non-shim 32-bit PV This documents, but does not fix, XSA-370. Reported-by: Jann Horn Signed-off-by: Ian Jackson Signed-off-by: George Dunlap Acked-by: Jan Beulich --- NB that the security team does not consider the security support status of un-shimmed 32-bit PV guests in this patch to be particularly useful. However, we do not consider ourselves to have the authority to decide to completely de-support 32-bit PV guests without community consultation. The support status in this patch should therefore be considered transitional. A permanent support status is proposed in a subsequent patch in this series. v2: - Fix double 'be' - Don't mention user -> kernel attacks, which have nothing to do with Xen --- SUPPORT.md | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/SUPPORT.md b/SUPPORT.md index 7db4568f1a..6dcd93e22f 100644 --- a/SUPPORT.md +++ b/SUPPORT.md @@ -84,7 +84,16 @@ Traditional Xen PV guest No hardware requirements - Status: Supported + Status, x86_64: Supported + Status, x86_32, shim: Supported + Status, x86_32, without shim: Supported, with caveats + +Due to architectural limitations, +32-bit PV guests must be assumed to be able to read arbitrary host memory +using speculative execution attacks. +Advisories will continue to be issued +for new vulnerabilities related to un-shimmed 32-bit PV guests +enabling denial-of-service attacks or privilege escalation attacks. ### x86/HVM -- 2.30.2