Description
In the Linux kernel, the following vulnerability has been resolved:
thermal: hwmon: Remove hwmon class device along with its parent
The current code creates one hwmon device per thermal zone type and that
device is registered under the first thermal zone of the given type.
That turns out to be problematic when the thermal zone holding the
hwmon device is removed.
For example, say that there are two ACPI thermal zones on a system
/sys/devices/virtual/thermal/thermal_zone0/
/sys/devices/virtual/thermal/thermal_zone1/
The current code registers a hwmon class device for thermal_zone0 only:
/sys/devices/virtual/thermal/thermal_zone0/hwmon0/
because the type is "acpitz" for both of them, but it adds a sysfs
attribute that belongs to thermal_zone1 under it:
/sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp2_input
There is also
/sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp1_input
which belongs to thermal_zone0.
When thermal_zone0 is removed, say because the ACPI thermal driver is
unbound from the underlying platform device, thermal_remove_hwmon_sysfs()
skips the removal of hwmon0 because of the temp2_input attribute
belonging to thermal_zone1 which effectively prevents thermal_zone0
removal from making progress.
Address this by making thermal_remove_hwmon_sysfs() remove the entire
hwmon class device interface for the given thermal zone type when the
thermal zone device holding it is removed.
To prevent races with thermal_add_hwmon_sysfs() that may interfere
with this, carry out the entire addition and removal of hwmon sysfs
interfaces for thermal zones under thermal_hwmon_list_lock.
Also adjust the layout of the labels in thermal_add_hwmon_sysfs() to
the current kernel coding style to align with the new "unlock" label.
thermal: hwmon: Remove hwmon class device along with its parent
The current code creates one hwmon device per thermal zone type and that
device is registered under the first thermal zone of the given type.
That turns out to be problematic when the thermal zone holding the
hwmon device is removed.
For example, say that there are two ACPI thermal zones on a system
/sys/devices/virtual/thermal/thermal_zone0/
/sys/devices/virtual/thermal/thermal_zone1/
The current code registers a hwmon class device for thermal_zone0 only:
/sys/devices/virtual/thermal/thermal_zone0/hwmon0/
because the type is "acpitz" for both of them, but it adds a sysfs
attribute that belongs to thermal_zone1 under it:
/sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp2_input
There is also
/sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp1_input
which belongs to thermal_zone0.
When thermal_zone0 is removed, say because the ACPI thermal driver is
unbound from the underlying platform device, thermal_remove_hwmon_sysfs()
skips the removal of hwmon0 because of the temp2_input attribute
belonging to thermal_zone1 which effectively prevents thermal_zone0
removal from making progress.
Address this by making thermal_remove_hwmon_sysfs() remove the entire
hwmon class device interface for the given thermal zone type when the
thermal zone device holding it is removed.
To prevent races with thermal_add_hwmon_sysfs() that may interfere
with this, carry out the entire addition and removal of hwmon sysfs
interfaces for thermal zones under thermal_hwmon_list_lock.
Also adjust the layout of the labels in thermal_add_hwmon_sysfs() to
the current kernel coding style to align with the new "unlock" label.
Published:
2026-09-17
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
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References
History
Thu, 17 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: thermal: hwmon: Remove hwmon class device along with its parent The current code creates one hwmon device per thermal zone type and that device is registered under the first thermal zone of the given type. That turns out to be problematic when the thermal zone holding the hwmon device is removed. For example, say that there are two ACPI thermal zones on a system /sys/devices/virtual/thermal/thermal_zone0/ /sys/devices/virtual/thermal/thermal_zone1/ The current code registers a hwmon class device for thermal_zone0 only: /sys/devices/virtual/thermal/thermal_zone0/hwmon0/ because the type is "acpitz" for both of them, but it adds a sysfs attribute that belongs to thermal_zone1 under it: /sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp2_input There is also /sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp1_input which belongs to thermal_zone0. When thermal_zone0 is removed, say because the ACPI thermal driver is unbound from the underlying platform device, thermal_remove_hwmon_sysfs() skips the removal of hwmon0 because of the temp2_input attribute belonging to thermal_zone1 which effectively prevents thermal_zone0 removal from making progress. Address this by making thermal_remove_hwmon_sysfs() remove the entire hwmon class device interface for the given thermal zone type when the thermal zone device holding it is removed. To prevent races with thermal_add_hwmon_sysfs() that may interfere with this, carry out the entire addition and removal of hwmon sysfs interfaces for thermal zones under thermal_hwmon_list_lock. Also adjust the layout of the labels in thermal_add_hwmon_sysfs() to the current kernel coding style to align with the new "unlock" label. | |
| Title | thermal: hwmon: Remove hwmon class device along with its parent | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-17T16:08:31.645Z
Reserved: 2026-09-11T19:38:34.800Z
Link: CVE-2026-90311
No data.
Status : Received
Published: 2026-09-17T17:17:28.870
Modified: 2026-09-17T17:17:28.870
Link: CVE-2026-90311
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.