CVE-2026-64373

Summary

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

cpufreq: Fix hotplug-suspend race during reboot

During system reboot, cpufreq_suspend() is called via the kernel_restart() -> device_shutdown() path. Unlike the normal system suspend path, the reboot path does not call freeze_processes(), so userspace processes and kernel threads remain active.

This allows CPU hotplug operations to run concurrently with cpufreq_suspend(). The original code has no synchronization with CPU hotplug, leading to a race condition where governor_data can be freed by the hotplug path while cpufreq_suspend() is still accessing it, resulting in a null pointer dereference:

Unable to handle kernel NULL pointer dereference Call Trace: do_kernel_fault+0x28/0x3c cpufreq_suspend+0xdc/0x160 device_shutdown+0x18/0x200 kernel_restart+0x40/0x80 arm64_sys_reboot+0x1b0/0x200

Fix this by adding cpus_read_lock()/cpus_read_unlock() to cpufreq_suspend() to block CPU hotplug operations while suspend is in progress.

[ rjw: Changelog edits ]

Affected Software

VendorProductVersion RangeStatus
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < 6d5dd354c37abaf4d60400c55c71f23ba2b33639affected
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < 9103078c7b3091a2fbb52af176f95982ee7dd7f8affected
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < cd4524ff6567fa4458a5bec4b017105e671d393eaffected
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < 73255d702c7560185fd5951aadcf7eb057c2f453affected
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < a0ef2fc89d28ca62923376c4b8ffaa57136a36beaffected
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < 6e175c00c62dca3d91b987015808b5d52e8db2b4affected
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < a0106b41f9a724868d390b8b3b4ea5ca0e04ea53affected
LinuxLinux65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 < a9029dd55696c651ee46912afa2a166fa456bb3eaffected
LinuxLinux8bfa06ea6e81bf08d2132d7e70c2b5313b34caf8affected
LinuxLinux7ccf3b8b7a12dc9da158c2e699c36d04b2496944affected
LinuxLinux5f466713989250938624afa79dc33bae20920700affected
LinuxLinux89ab39da1452d272007acc5912d4008047b86706affected
LinuxLinuxcb4b4601f910c78d2b49f637a12ef98b41cb76a9affected
LinuxLinux4.4.198 < 4.5affected
LinuxLinux4.9.198 < 4.10affected
LinuxLinux4.14.151 < 4.15affected
LinuxLinux4.19.81 < 4.20affected
LinuxLinux5.3.8 < 5.4affected
LinuxLinux5.4affected
LinuxLinux0 < 5.4unaffected
LinuxLinux5.10.261 <= 5.10.*unaffected
LinuxLinux5.15.212 <= 5.15.*unaffected
LinuxLinux6.1.178 <= 6.1.*unaffected
LinuxLinux6.6.145 <= 6.6.*unaffected
LinuxLinux6.12.96 <= 6.12.*unaffected
LinuxLinux6.18.39 <= 6.18.*unaffected
LinuxLinux7.1.4 <= 7.1.*unaffected
LinuxLinux7.2-rc1 <= *unaffected

Weaknesses

References