Upstream information

CVE-2022-50471 at MITRE

Description

In the Linux kernel, the following vulnerability has been resolved:

xen/gntdev: Accommodate VMA splitting

Prior to this commit, the gntdev driver code did not handle the
following scenario correctly with paravirtualized (PV) Xen domains:

* User process sets up a gntdev mapping composed of two grant mappings
(i.e., two pages shared by another Xen domain).
* User process munmap()s one of the pages.
* User process munmap()s the remaining page.
* User process exits.

In the scenario above, the user process would cause the kernel to log
the following messages in dmesg for the first munmap(), and the second
munmap() call would result in similar log messages:

BUG: Bad page map in process doublemap.test pte:... pmd:...
page:0000000057c97bff refcount:1 mapcount:-1 \
mapping:0000000000000000 index:0x0 pfn:...
...
page dumped because: bad pte
...
file:gntdev fault:0x0 mmap:gntdev_mmap [xen_gntdev] readpage:0x0
...
Call Trace:
<TASK>
dump_stack_lvl+0x46/0x5e
print_bad_pte.cold+0x66/0xb6
unmap_page_range+0x7e5/0xdc0
unmap_vmas+0x78/0xf0
unmap_region+0xa8/0x110
__do_munmap+0x1ea/0x4e0
__vm_munmap+0x75/0x120
__x64_sys_munmap+0x28/0x40
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x61/0xcb
...

For each munmap() call, the Xen hypervisor (if built with CONFIG_DEBUG)
would print out the following and trigger a general protection fault in
the affected Xen PV domain:

(XEN) d0v... Attempt to implicitly unmap d0's grant PTE ...
(XEN) d0v... Attempt to implicitly unmap d0's grant PTE ...

As of this writing, gntdev_grant_map structure's vma field (referred to
as map->vma below) is mainly used for checking the start and end
addresses of mappings. However, with split VMAs, these may change, and
there could be more than one VMA associated with a gntdev mapping.
Hence, remove the use of map->vma and rely on map->pages_vm_start for
the original start address and on (map->count << PAGE_SHIFT) for the
original mapping size. Let the invalidate() and find_special_page()
hooks use these.

Also, given that there can be multiple VMAs associated with a gntdev
mapping, move the "mmu_interval_notifier_remove(&map->notifier)" call to
the end of gntdev_put_map, so that the MMU notifier is only removed
after the closing of the last remaining VMA.

Finally, use an atomic to prevent inadvertent gntdev mapping re-use,
instead of using the map->live_grants atomic counter and/or the map->vma
pointer (the latter of which is now removed). This prevents the
userspace from mmap()'ing (with MAP_FIXED) a gntdev mapping over the
same address range as a previously set up gntdev mapping. This scenario
can be summarized with the following call-trace, which was valid prior
to this commit:

mmap
gntdev_mmap
mmap (repeat mmap with MAP_FIXED over the same address range)
gntdev_invalidate
unmap_grant_pages (sets 'being_removed' entries to true)
gnttab_unmap_refs_async
unmap_single_vma
gntdev_mmap (maps the shared pages again)
munmap
gntdev_invalidate
unmap_grant_pages
(no-op because 'being_removed' entries are true)
unmap_single_vma (For PV domains, Xen reports that a granted page
is being unmapped and triggers a general protection fault in the
affected domain, if Xen was built with CONFIG_DEBUG)

The fix for this last scenario could be worth its own commit, but we
opted for a single commit, because removing the gntdev_grant_map
structure's vma field requires guarding the entry to gntdev_mmap(), and
the live_grants atomic counter is not sufficient on its own to prevent
the mmap() over a pre-existing mapping.

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having moderate severity.

CVSS v3 Scores
CVSS detail SUSE
Base Score 5.5
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
CVSSv3 Version 3.1
CVSS v4 Scores
CVSS detail SUSE
Base Score 6.8
Vector CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Attack Vector Local
Attack Complexity Low
Attack Requirements None
Privileges Required Low
User Interaction None
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact None
Vulnerable System Availability Impact High
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
CVSSv4 Version 4.0

Note from the SUSE Security Team on the kernel-default package

SUSE will no longer fix all CVEs in the Linux Kernel anymore, but declare some bug classes as won't fix. Please refer to TID 21496 for more details.

SUSE Bugzilla entry: 1251110 [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 Linux Enterprise Desktop 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Desktop 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Desktop 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP6 kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP6 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP6 kernel-source-azure Not affected
SUSE Linux Enterprise High Performance Computing 15 SP7 kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP7 kernel-source-azure Not affected
SUSE Linux Enterprise Live Patching 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Micro 5.1 kernel-default Affected
SUSE Linux Enterprise Micro 5.1 kernel-rt Affected
SUSE Linux Enterprise Micro 5.1 kernel-source Affected
SUSE Linux Enterprise Micro 5.1 kernel-source-rt Affected
SUSE Linux Enterprise Micro 5.2 kernel-default Affected
SUSE Linux Enterprise Micro 5.2 kernel-rt Affected
SUSE Linux Enterprise Micro 5.2 kernel-source Affected
SUSE Linux Enterprise Micro 5.2 kernel-source-rt Affected
SUSE Linux Enterprise Micro 5.3 kernel-default Not affected
SUSE Linux Enterprise Micro 5.3 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-default Not affected
SUSE Linux Enterprise Micro 5.4 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.5 kernel-default Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source-rt Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Legacy 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Module for Legacy 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Public Cloud 15 SP6 kernel-source-azure Not affected
SUSE Linux Enterprise Module for Public Cloud 15 SP7 kernel-source-azure Not affected
SUSE Linux Enterprise Real Time 15 SP6 kernel-source-rt Not affected
SUSE Linux Enterprise Real Time 15 SP7 kernel-source-rt Not affected
SUSE Linux Enterprise Server 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Server 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP6 kernel-source-azure Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-source-azure Not affected
SUSE Linux Enterprise Server 16.0 kernel-default Not affected
SUSE Linux Enterprise Server 16.0 kernel-source Not affected
SUSE Linux Enterprise Server 16.0 kernel-source-azure Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source-azure Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-source-azure Not affected
SUSE Linux Enterprise Server for SAP Applications 16.0 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 16.0 kernel-source-azure Not affected
SUSE Linux Enterprise Workstation Extension 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Workstation Extension 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-default Not affected
SUSE Linux Micro 6.0 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-source-rt Not affected
SUSE Linux Micro 6.1 kernel-default Not affected
SUSE Linux Micro 6.1 kernel-source Not affected
SUSE Linux Micro 6.1 kernel-source-rt Not affected
SUSE Linux Micro 6.2 kernel-source Not affected
SUSE Real Time Module 15 SP6 kernel-source-rt Not affected
SUSE Real Time Module 15 SP7 kernel-source-rt Not affected
openSUSE Leap 15.6 kernel-default Not affected
openSUSE Leap 15.6 kernel-source Not affected
openSUSE Leap 15.6 kernel-source-azure Not affected
openSUSE Leap 15.6 kernel-source-rt Not affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 15 SP3 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-default Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP4 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Live Patching 12 SP5 kernel-default Affected
SUSE Linux Enterprise Live Patching 12 SP5 kernel-source Affected
SUSE Linux Enterprise Live Patching 15 SP3 kernel-default Affected
SUSE Linux Enterprise Live Patching 15 SP3 kernel-source Affected
SUSE Linux Enterprise Live Patching 15 SP4 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Live Patching 15 SP5 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP3 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP3 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-default Affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-source Affected
SUSE Linux Enterprise Server 12 SP5 kernel-source Affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-default Affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-source Affected
SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security kernel-default Affected
SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security kernel-source Affected
SUSE Linux Enterprise Server 15 SP3 kernel-source Affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-source Affected
SUSE Manager Proxy 4.3 kernel-source Not affected
SUSE Manager Proxy LTS 4.3 kernel-default Not affected
SUSE Manager Proxy LTS 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server LTS 4.3 kernel-default Not affected
SUSE Manager Retail Branch Server LTS 4.3 kernel-source Not affected
SUSE Manager Server 4.3 kernel-source Not affected
SUSE Manager Server LTS 4.3 kernel-default Not affected
SUSE Manager Server LTS 4.3 kernel-source Not affected
Products past their end of life and not receiving proactive updates anymore.
SUSE CaaS Platform 4.0 kernel-source Affected
SUSE Enterprise Storage 6 kernel-source Affected
SUSE Enterprise Storage 7 kernel-source Affected
SUSE Enterprise Storage 7.1 kernel-source Affected
SUSE Linux Enterprise Desktop 11 SP4 kernel-source Affected
SUSE Linux Enterprise Desktop 12 SP2 kernel-source Affected
SUSE Linux Enterprise Desktop 12 SP4 kernel-source Affected
SUSE Linux Enterprise Desktop 15 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP1 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP2 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP3 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP1 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP2 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15-LTSS kernel-source Affected
SUSE Linux Enterprise Micro 5.0 kernel-default Affected
SUSE Linux Enterprise Module for Basesystem 15 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP1 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP2 kernel-source Affected
SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP2 kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP3 kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP3 kernel-source-rt Affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source-rt Not affected
SUSE Linux Enterprise Real Time 15 SP5 kernel-source-rt Not affected
SUSE Linux Enterprise Server 11 SP4 kernel-source Affected
SUSE Linux Enterprise Server 11 SP4 LTSS kernel-default Affected
SUSE Linux Enterprise Server 11 SP4 LTSS kernel-source Affected
SUSE Linux Enterprise Server 11 SP4-LTSS kernel-source Affected
SUSE Linux Enterprise Server 12 SP2 kernel-source Affected
SUSE Linux Enterprise Server 12 SP2-BCL kernel-source Affected
SUSE Linux Enterprise Server 12 SP2-ESPOS kernel-source Affected
SUSE Linux Enterprise Server 12 SP2-LTSS kernel-default Affected
SUSE Linux Enterprise Server 12 SP2-LTSS kernel-source Affected
SUSE Linux Enterprise Server 12 SP4 kernel-source Affected
SUSE Linux Enterprise Server 12 SP4-ESPOS kernel-source Affected
SUSE Linux Enterprise Server 12 SP4-LTSS kernel-default Affected
SUSE Linux Enterprise Server 12 SP4-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 kernel-source Affected
SUSE Linux Enterprise Server 15 SP1 kernel-source Affected
SUSE Linux Enterprise Server 15 SP1-BCL kernel-source Affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP2 kernel-source Affected
SUSE Linux Enterprise Server 15 SP2-BCL kernel-source Affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP3-BCL kernel-source Affected
SUSE Linux Enterprise Server 15-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15-LTSS kernel-source Affected
SUSE Linux Enterprise Server for Raspberry Pi 12 SP2 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 12 SP2 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 12 SP4 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-default Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-source Not affected
SUSE Manager Proxy 4.0 kernel-source Affected
SUSE Manager Proxy 4.1 kernel-source Affected
SUSE Manager Proxy 4.2 kernel-source Affected
SUSE Manager Retail Branch Server 4.0 kernel-source Affected
SUSE Manager Retail Branch Server 4.1 kernel-source Affected
SUSE Manager Retail Branch Server 4.2 kernel-source Affected
SUSE Manager Server 4.0 kernel-source Affected
SUSE Manager Server 4.1 kernel-source Affected
SUSE Manager Server 4.2 kernel-source Affected
SUSE OpenStack Cloud 7 kernel-source Affected
SUSE OpenStack Cloud 9 kernel-source Affected
SUSE OpenStack Cloud Crowbar 9 kernel-source Affected
SUSE Real Time Module 15 SP3 kernel-source-rt Affected
SUSE Real Time Module 15 SP4 kernel-source-rt Not affected
SUSE Real Time Module 15 SP5 kernel-source-rt Not affected
openSUSE Leap 15.3 kernel-source Affected
openSUSE Leap 15.3 kernel-source-rt Affected
openSUSE Leap 15.4 kernel-source Not affected
openSUSE Leap 15.4 kernel-source-rt Not affected
openSUSE Leap 15.5 kernel-source Not affected
openSUSE Leap 15.5 kernel-source-rt Not affected


SUSE Timeline for this CVE

CVE page created: Sat Oct 4 20:00:03 2025
CVE page last modified: Tue Oct 7 22:00:47 2025