CVE-2025-38539

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> tracing: Add down_write(trace_event_sem) when adding trace event<br /> <br /> When a module is loaded, it adds trace events defined by the module. It<br /> may also need to modify the modules trace printk formats to replace enum<br /> names with their values.<br /> <br /> If two modules are loaded at the same time, the adding of the event to the<br /> ftrace_events list can corrupt the walking of the list in the code that is<br /> modifying the printk format strings and crash the kernel.<br /> <br /> The addition of the event should take the trace_event_sem for write while<br /> it adds the new event.<br /> <br /> Also add a lockdep_assert_held() on that semaphore in<br /> __trace_add_event_dirs() as it iterates the list.