CVE-2025-38704

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> rcu/nocb: Fix possible invalid rdp&amp;#39;s-&gt;nocb_cb_kthread pointer access<br /> <br /> In the preparation stage of CPU online, if the corresponding<br /> the rdp&amp;#39;s-&gt;nocb_cb_kthread does not exist, will be created,<br /> there is a situation where the rdp&amp;#39;s rcuop kthreads creation fails,<br /> and then de-offload this CPU&amp;#39;s rdp, does not assign this CPU&amp;#39;s<br /> rdp-&gt;nocb_cb_kthread pointer, but this rdp&amp;#39;s-&gt;nocb_gp_rdp and<br /> rdp&amp;#39;s-&gt;rdp_gp-&gt;nocb_gp_kthread is still valid.<br /> <br /> This will cause the subsequent re-offload operation of this offline<br /> CPU, which will pass the conditional check and the kthread_unpark()<br /> will access invalid rdp&amp;#39;s-&gt;nocb_cb_kthread pointer.<br /> <br /> This commit therefore use rdp&amp;#39;s-&gt;nocb_gp_kthread instead of<br /> rdp_gp&amp;#39;s-&gt;nocb_gp_kthread for safety check.