Upstream information

CVE-2021-4440 at MITRE

Description

In the Linux kernel, the following vulnerability has been resolved: x86/xen: Drop USERGS_SYSRET64 paravirt call commit afd30525a659ac0ae0904f0cb4a2ca75522c3123 upstream. USERGS_SYSRET64 is used to return from a syscall via SYSRET, but a Xen PV guest will nevertheless use the IRET hypercall, as there is no sysret PV hypercall defined. So instead of testing all the prerequisites for doing a sysret and then mangling the stack for Xen PV again for doing an iret just use the iret exit from the beginning. This can easily be done via an ALTERNATIVE like it is done for the sysenter compat case already. It should be noted that this drops the optimization in Xen for not restoring a few registers when returning to user mode, but it seems as if the saved instructions in the kernel more than compensate for this drop (a kernel build in a Xen PV guest was slightly faster with this patch applied). While at it remove the stale sysret32 remnants. [ pawan: Brad Spengler and Salvatore Bonaccorso <carnil@debian.org> reported a problem with the 5.10 backport commit edc702b4a820 ("x86/entry_64: Add VERW just before userspace transition"). When CONFIG_PARAVIRT_XXL=y, CLEAR_CPU_BUFFERS is not executed in syscall_return_via_sysret path as USERGS_SYSRET64 is runtime patched to: .cpu_usergs_sysret64 = { 0x0f, 0x01, 0xf8, 0x48, 0x0f, 0x07 }, // swapgs; sysretq which is missing CLEAR_CPU_BUFFERS. It turns out dropping USERGS_SYSRET64 simplifies the code, allowing CLEAR_CPU_BUFFERS to be explicitly added to syscall_return_via_sysret path. Below is with CONFIG_PARAVIRT_XXL=y and this patch applied: syscall_return_via_sysret: ... <+342>: swapgs <+345>: xchg %ax,%ax <+347>: verw -0x1a2(%rip) <------ <+354>: sysretq ]

SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having moderate severity.

CVSS v3 Scores
  SUSE
Base Score 4.4
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Impact Low
Integrity Impact None
Availability Impact Low
CVSSv3 Version 3.1
SUSE Bugzilla entry: 1227069 [NEW]

No SUSE Security Announcements cross referenced.


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Enterprise Storage 7.1 kernel-default Already fixed
SUSE Enterprise Storage 7.1 kernel-source Already fixed
SUSE Linux Enterprise Desktop 15 SP5 kernel-default Already fixed
SUSE Linux Enterprise Desktop 15 SP5 kernel-source Already fixed
SUSE Linux Enterprise Desktop 15 SP6 kernel-default Already fixed
SUSE Linux Enterprise Desktop 15 SP6 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 12 SP5 kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 12 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 12 SP5 kernel-source-azure Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-default Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-source-azure Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP6 kernel-default Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP6 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP6 kernel-source-azure Already fixed
SUSE Linux Enterprise Micro 5.1 kernel-default Already fixed
SUSE Linux Enterprise Micro 5.1 kernel-rt Already fixed
SUSE Linux Enterprise Micro 5.1 kernel-source-rt Already fixed
SUSE Linux Enterprise Micro 5.2 kernel-default Already fixed
SUSE Linux Enterprise Micro 5.2 kernel-rt Already fixed
SUSE Linux Enterprise Micro 5.2 kernel-source-rt Already fixed
SUSE Linux Enterprise Micro 5.3 kernel-default Already fixed
SUSE Linux Enterprise Micro 5.3 kernel-rt Already fixed
SUSE Linux Enterprise Micro 5.3 kernel-source-rt Already fixed
SUSE Linux Enterprise Micro 5.4 kernel-default Already fixed
SUSE Linux Enterprise Micro 5.4 kernel-rt Already fixed
SUSE Linux Enterprise Micro 5.4 kernel-source-rt Already fixed
SUSE Linux Enterprise Micro 5.5 kernel-source-rt Already fixed
SUSE Linux Enterprise Module for Basesystem 15 SP5 kernel-default Already fixed
SUSE Linux Enterprise Module for Basesystem 15 SP5 kernel-source Already fixed
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-default Already fixed
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-source Already fixed
SUSE Linux Enterprise Module for Development Tools 15 SP5 kernel-default Already fixed
SUSE Linux Enterprise Module for Development Tools 15 SP5 kernel-source Already fixed
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-default Already fixed
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-source Already fixed
SUSE Linux Enterprise Module for Public Cloud 15 SP5 kernel-source-azure Already fixed
SUSE Linux Enterprise Module for Public Cloud 15 SP6 kernel-source-azure Already fixed
SUSE Linux Enterprise Real Time 12 SP5 kernel-source-rt Not affected
SUSE Linux Enterprise Real Time 15 SP5 kernel-source-rt Already fixed
SUSE Linux Enterprise Real Time 15 SP6 kernel-source-rt Already fixed
SUSE Linux Enterprise Server 12 SP5 kernel-default Not affected
SUSE Linux Enterprise Server 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 12 SP5 kernel-source-azure Not affected
SUSE Linux Enterprise Server 15 SP5 kernel-default Already fixed
SUSE Linux Enterprise Server 15 SP5 kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP5 kernel-source-azure Already fixed
SUSE Linux Enterprise Server 15 SP6 kernel-default Already fixed
SUSE Linux Enterprise Server 15 SP6 kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP6 kernel-source-azure Already fixed
SUSE Linux Enterprise Server for SAP Applications 12 SP5 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP5 kernel-source-azure Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-default Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-source Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-source-azure Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-default Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source-azure Already fixed
SUSE Manager Proxy 4.3 kernel-default Already fixed
SUSE Manager Proxy 4.3 kernel-source Already fixed
SUSE Manager Retail Branch Server 4.3 kernel-default Already fixed
SUSE Manager Retail Branch Server 4.3 kernel-source Already fixed
SUSE Manager Server 4.3 kernel-default Already fixed
SUSE Manager Server 4.3 kernel-source Already fixed
SUSE Real Time Module 15 SP5 kernel-source-rt Already fixed
SUSE Real Time Module 15 SP6 kernel-source-rt Already fixed
openSUSE Leap 15.5 kernel-default Already fixed
openSUSE Leap 15.5 kernel-source Already fixed
openSUSE Leap 15.5 kernel-source-azure Already fixed
openSUSE Leap 15.5 kernel-source-rt Already fixed
openSUSE Leap 15.6 kernel-default Already fixed
openSUSE Leap 15.6 kernel-source Already fixed
openSUSE Leap 15.6 kernel-source-azure Already fixed
openSUSE Leap 15.6 kernel-source-rt Already fixed
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise Desktop 15 SP4 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP2 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS kernel-default Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP3 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-default Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP4 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS kernel-default Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-default Already fixed
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-source Already fixed
SUSE Linux Enterprise Module for Basesystem 15 SP2 kernel-source Already fixed
SUSE Linux Enterprise Module for Basesystem 15 SP3 kernel-source Already fixed
SUSE Linux Enterprise Module for Basesystem 15 SP4 kernel-source Already fixed
SUSE Linux Enterprise Module for Development Tools 15 SP2 kernel-source Already fixed
SUSE Linux Enterprise Module for Development Tools 15 SP3 kernel-source Already fixed
SUSE Linux Enterprise Module for Development Tools 15 SP4 kernel-source Already fixed
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-default Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2 kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-default Already fixed
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP3 kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-default Already fixed
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP4 kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-default Already fixed
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-source Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP2 kernel-default Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP2 kernel-source Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-default Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-source Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-default Already fixed
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-source Already fixed
Products past their end of life and not receiving proactive updates anymore.
HPE Helion OpenStack 8 kernel-source Not affected
SUSE CaaS Platform 4.0 kernel-source Not affected
SUSE Enterprise Storage 6 kernel-source Not affected
SUSE Enterprise Storage 7 kernel-source Already fixed
SUSE Linux Enterprise Desktop 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 12 SP3 kernel-source Not affected
SUSE Linux Enterprise Desktop 12 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP2 kernel-source Already fixed
SUSE Linux Enterprise Desktop 15 SP3 kernel-source Already fixed
SUSE Linux Enterprise High Performance Computing 15 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15-LTSS kernel-source Not affected
SUSE Linux Enterprise Micro 5.0 kernel-default Not affected
SUSE Linux Enterprise Module for Basesystem 15 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP2 kernel-source Already fixed
SUSE Linux Enterprise Real Time 15 SP3 kernel-source Already fixed
SUSE Linux Enterprise Real Time 15 SP3 kernel-source-rt Already fixed
SUSE Linux Enterprise Real Time 15 SP4 kernel-source Already fixed
SUSE Linux Enterprise Real Time 15 SP4 kernel-source-rt Already fixed
SUSE Linux Enterprise Server 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS kernel-default Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 12 SP3 kernel-source Not affected
SUSE Linux Enterprise Server 12 SP3-BCL kernel-source Not affected
SUSE Linux Enterprise Server 12 SP3-ESPOS kernel-source Not affected
SUSE Linux Enterprise Server 12 SP3-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 12 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 12 SP4-ESPOS kernel-source Not affected
SUSE Linux Enterprise Server 12 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 12 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2-BCL kernel-source Already fixed
SUSE Linux Enterprise Server 15 SP3-BCL kernel-source Already fixed
SUSE Linux Enterprise Server 15-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15-LTSS kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP3 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP4 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 12 SP4 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 kernel-source Not affected
SUSE Manager Proxy 4.0 kernel-source Not affected
SUSE Manager Proxy 4.1 kernel-source Already fixed
SUSE Manager Proxy 4.2 kernel-source Already fixed
SUSE Manager Retail Branch Server 4.0 kernel-source Not affected
SUSE Manager Retail Branch Server 4.1 kernel-source Already fixed
SUSE Manager Retail Branch Server 4.2 kernel-source Already fixed
SUSE Manager Server 4.0 kernel-source Not affected
SUSE Manager Server 4.1 kernel-source Already fixed
SUSE Manager Server 4.2 kernel-source Already fixed
SUSE OpenStack Cloud 8 kernel-source Not affected
SUSE OpenStack Cloud 9 kernel-source Not affected
SUSE OpenStack Cloud Crowbar 8 kernel-source Not affected
SUSE OpenStack Cloud Crowbar 9 kernel-source Not affected
SUSE Real Time Module 15 SP3 kernel-source-rt Already fixed
SUSE Real Time Module 15 SP4 kernel-source-rt Already fixed
openSUSE Leap 15.3 kernel-source Already fixed
openSUSE Leap 15.3 kernel-source-rt Already fixed
openSUSE Leap 15.4 kernel-source Already fixed
openSUSE Leap 15.4 kernel-source-azure Already fixed
openSUSE Leap 15.4 kernel-source-rt Already fixed
Products at an unknown state of their lifecycle.
SUSE CaaS Platform Toolchain 3 kernel-source Not affected


SUSE Timeline for this CVE

CVE page created: Tue Jun 25 18:00:11 2024
CVE page last modified: Wed Jul 3 12:37:11 2024