CVE-2026-74471tracing: Check return value of __register_event() in trace_module_add_events()

Official description

In the Linux kernel, the following vulnerability has been resolved: tracing: Check return value of __register_event() in trace_module_add_events() trace_module_add_events() ignores the return value of __register_event() and unconditionally calls __add_event_to_tracers() for each event. If __register_event() fails (for example, if event_init() fails), the trace_event_call is not added to ftrace_events list, but __add_event_to_tracers() still creates a trace_event_file pointing to it. If module loading subsequently fails and module memory is freed, tracing state retains a stale trace_event_call pointer in trace_event_file, leading to a use-after-free when tracefs or tracing subsystem operations are later executed. Fix this by checking the return value of __register_event() and only calling __add_event_to_tracers() if event registration succeeded.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/3bf965a2827c44f03294107703e7ba53fbd0a69a
• https://git.kernel.org/stable/c/9d6d79744f01eacaf3d5522f4fcd59939581abfd
• https://git.kernel.org/stable/c/54b7a358f6399c1242d2fb7f4f96085af34baa5e
• https://git.kernel.org/stable/c/d61ee2a27dfd5eb43ddc18af40168f5b9eb1cea5
• https://git.kernel.org/stable/c/22f954f7a8afe975e85517aff41b35defe05144b
• https://git.kernel.org/stable/c/cbb5ed3be9cae70e1c12b1991009b4e12bf4a4ca
• https://git.kernel.org/stable/c/000765dcdc3edf128990762790543adc4b868f6c
• https://git.kernel.org/stable/c/ac8719969e6c3c54e939834df812bc41f25453cf