insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. To address XSA-401, code was moved inside a function in Xen. This code movement missed a variable changing meaning / value between old and new code positions. The now wrong use of the variable did lead to a wrong TLB flush condition, omitting flushes where such are necessary.
[
{
"vendor": "Xen",
"product": "xen",
"versions": [
{
"version": "consult Xen advisory XSA-408",
"status": "unknown"
}
]
}
]
www.openwall.com/lists/oss-security/2022/07/26/2
www.openwall.com/lists/oss-security/2022/07/26/3
xenbits.xen.org/xsa/advisory-408.html
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HUFIMNGYP5VQAA6KE3T2I5GW6UP6F7BS/
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MYI3OMJ7RIZNL3C6GUWNANNPEUUID6FM/
www.debian.org/security/2022/dsa-5272
xenbits.xenproject.org/xsa/advisory-408.txt