CVE-2025-38522

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> sched/ext: Prevent update_locked_rq() calls with NULL rq<br /> <br /> Avoid invoking update_locked_rq() when the runqueue (rq) pointer is NULL<br /> in the SCX_CALL_OP and SCX_CALL_OP_RET macros.<br /> <br /> Previously, calling update_locked_rq(NULL) with preemption enabled could<br /> trigger the following warning:<br /> <br /> BUG: using __this_cpu_write() in preemptible [00000000]<br /> <br /> This happens because __this_cpu_write() is unsafe to use in preemptible<br /> context.<br /> <br /> rq is NULL when an ops invoked from an unlocked context. In such cases, we<br /> don&amp;#39;t need to store any rq, since the value should already be NULL<br /> (unlocked). Ensure that update_locked_rq() is only called when rq is<br /> non-NULL, preventing calling __this_cpu_write() on preemptible context.