CVE-2025-40174: x86/mm: Fix SMP ordering in switch_mm_irqs_off()
In the Linux kernel, the following vulnerability has been resolved:
x86/mm: Fix SMP ordering in switchmmirqsoff()
Stephen noted that it is possible to not have an smpmb() between the loadedmm store and the tlbgen load in switchmm(), meaning the ordering against flushtlbmmrange() goes out the window, and it becomes possible for switchmm() to not observe a recent tlbgen update and fail to flush the TLBs.
[ dhansen: merge conflict fixed by Ingo ]
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2025-40174?
CVE-2025-40174 is classified as a medium severity vulnerability in the Linux kernel.
How do I fix CVE-2025-40174?
To fix CVE-2025-40174, update your Linux kernel to the latest stable version that includes the patch.
What impact does CVE-2025-40174 have on system security?
CVE-2025-40174 may impact system stability and security by affecting memory handling in multi-processor environments.
Is CVE-2025-40174 exploitable remotely?
CVE-2025-40174 is not known to be remotely exploitable but could be a risk in local privilege escalation scenarios.
Which Linux kernel versions are affected by CVE-2025-40174?
CVE-2025-40174 affects certain versions of the Linux kernel prior to the release containing the fix.