Executive brief
The Linux kernel's coretemp driver has a memory leak that affects processors without Package Thermal Status (PTS) support. On these CPUs, memory allocated for thermal sensor data is never freed when the driver is unloaded, potentially consuming system memory with repeated module load/unload cycles. This impacts system stability and resource availability on affected Intel processors.
Technical details
The vulnerability is a resource leak (CWE-401) in the coretemp hwmon driver's memory management. The pdata->core_data array is allocated in init_temp_data() when the first core temperature sensor is initialized, but on CPUs without X86_FEATURE_PTS, the package temperature interface is never created, so destroy_temp_data() is never called for package data. As a result, coretemp_device_remove() frees the platform data structure without releasing the core_data array, leaving it allocated. The fix adds an explicit kfree() call in coretemp_device_remove() to release the array. This is a low-risk local issue requiring module unload/reload or system reboot to trigger, with no authentication required and no elevation of privilege.
Affected products
- Linux Linux Kernel versions prior to the patch (hwmon: coretemp Fix core_data leak fix)
Timeline
- 2026-09-17: disclosed