cve/2025/CVE-2025-21840.md
2025-09-29 21:09:30 +02:00

1.8 KiB

CVE-2025-21840

Description

In the Linux kernel, the following vulnerability has been resolved:thermal/netlink: Prevent userspace segmentation fault by adjusting UAPI headerThe intel-lpmd tool [1], which uses the THERMAL_GENL_ATTR_CPU_CAPABILITYattribute to receive HFI events from kernel space, encounters asegmentation fault after commit 1773572863c4 ("thermal: netlink: Add thecommands and the events for the thresholds").The issue arises because the THERMAL_GENL_ATTR_CPU_CAPABILITY raw valuewas changed while intel_lpmd still uses the old value.Although intel_lpmd can be updated to check the THERMAL_GENL_VERSION anduse the appropriate THERMAL_GENL_ATTR_CPU_CAPABILITY value, the commititself is questionable.The commit introduced a new element in the middle of enum thermal_genl_attr,which affects many existing attributes and introduces potential risksand unnecessary maintenance burdens for userspace thermal netlink eventusers.Solve the issue by moving the newly introducedTHERMAL_GENL_ATTR_TZ_PREV_TEMP attribute to the end of theenum thermal_genl_attr. This ensures that all existing thermal genericnetlink attributes remain unaffected.[ rjw: Subject edits ]

POC

Reference

No PoCs from references.

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