openSUSE Security Update : the Linux Kernel (openSUSE-2018-515) (Spectre)
Medium Nessus Plugin ID 110105
SynopsisThe remote openSUSE host is missing a security update.
DescriptionThe openSUSE Leap 15.0 kernel was updated to receive various security and bugfixes.
The following security bugs were fixed :
- CVE-2018-3639: Systems with microprocessors utilizing speculative execution and speculative execution of memory reads before the addresses of all prior memory writes are known may allow unauthorized disclosure of information to an attacker with local user access via a side-channel analysis, aka Speculative Store Bypass (SSB), Variant 4 (bsc#1087082).
A new boot commandline option was introduced, 'spec_store_bypass_disable', which can have following values :
- auto: Kernel detects whether your CPU model contains an implementation of Speculative Store Bypass and picks the most appropriate mitigation.
- on: disable Speculative Store Bypass
- off: enable Speculative Store Bypass
- prctl: Control Speculative Store Bypass per thread via prctl. Speculative Store Bypass is enabled for a process by default. The state of the control is inherited on fork.
- seccomp: Same as 'prctl' above, but all seccomp threads will disable SSB unless they explicitly opt out.
The default is 'seccomp', meaning programs need explicit opt-in into the mitigation.
Status can be queried via the /sys/devices/system/cpu/vulnerabilities/spec_store_bypas s file, containing :
- 'Mitigation: Speculative Store Bypass disabled'
- 'Mitigation: Speculative Store Bypass disabled via prctl'
- 'Mitigation: Speculative Store Bypass disabled via prctl and seccomp'
The following non-security bugs were fixed :
- allow_unsupported: add module tainting on feature use (FATE#323394).
- powerpc/64/kexec: fix race in kexec when XIVE is shutdown (bsc#1088273).
- reiserfs: mark read-write mode unsupported (FATE#323394).
- reiserfs: package in separate KMP (FATE#323394).
SolutionUpdate the affected the Linux Kernel packages.