CVE-2024-50127

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: sched: arreglado use-after-free en taprio_change(). En 'taprio_change()', el puntero 'admin' puede quedar colgando debido al cambio/eliminación de sched causado por 'advance_sched()', y la sección crítica protegida por 'q->current_entry_lock' es demasiado pequeña para evitar tal escenario (que causa el use-after-free detectado por KASAN). Solucione esto al preferir 'rcu_replace_pointer()' sobre 'rcu_assign_pointer()' para actualizar 'admin' inmediatamente antes de un intento de liberación de programación.

In the Linux kernel, the following vulnerability has been resolved: net: sched: fix use-after-free in taprio_change() In 'taprio_change()', 'admin' pointer may become dangling due to sched switch / removal caused by 'advance_sched()', and critical section protected by 'q->current_entry_lock' is too small to prevent from such a scenario (which causes use-after-free detected by KASAN). Fix this by prefer 'rcu_replace_pointer()' over 'rcu_assign_pointer()' to update 'admin' immediately before an attempt to schedule freeing.

Ye Zhang and Nicolas Wu discovered that the io_uring subsystem in the Linux kernel did not properly handle locking for rings with IOPOLL, leading to a double-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system.