This update for xen to version 4.9.2 fixes several issues.
This feature was added:
- Added script, udev rule and systemd service to watch for vcpu
online/offline events in a HVM domU. They are triggered via ‘xl vcpu-set
domU N’
These security issues were fixed:
- CVE-2018-8897: Prevent mishandling of debug exceptions on x86 (XSA-260,
bsc#1090820)
- Handle HPET timers in IO-APIC mode correctly to prevent malicious or
buggy HVM guests from causing a hypervisor crash or potentially
privilege escalation/information leaks (XSA-261, bsc#1090822)
- Prevent unbounded loop, induced by qemu allowing an attacker to
permanently keep a physical CPU core busy (XSA-262, bsc#1090823)
- CVE-2018-10472: x86 HVM guest OS users (in certain configurations) were
able to read arbitrary dom0 files via QMP live insertion of a CDROM, in
conjunction with specifying the target file as the backing file of a
snapshot (bsc#1089152).
- CVE-2018-10471: x86 PV guest OS users were able to cause a denial of
service (out-of-bounds zero write and hypervisor crash) via unexpected
INT 80 processing, because of an incorrect fix for CVE-2017-5754
(bsc#1089635).
- CVE-2018-7540: x86 PV guest OS users were able to cause a denial of
service (host OS CPU hang) via non-preemptable L3/L4 pagetable freeing
(bsc#1080635).
- CVE-2018-7541: Guest OS users were able to cause a denial of service
(hypervisor crash) or gain privileges by triggering a grant-table
transition from v2 to v1 (bsc#1080662).
- CVE-2018-7542: x86 PVH guest OS users were able to cause a denial of
service (NULL pointer dereference and hypervisor crash) by leveraging
the mishandling
of configurations that lack a Local APIC (bsc#1080634).
These non-security issues were fixed:
- bsc#1087252: Update built-in defaults for xenstored in stubdom, keep
default to run xenstored as daemon in dom0
- bsc#1087251: Preserve xen-syms from xen-dbg.gz to allow processing
vmcores with crash(1)
- bsc#1072834: Prevent unchecked MSR access error