CVE-2026-46259

In the Linux kernel, the following vulnerability has been resolved: procfs: fix missing RCU protection when reading real_parent in do_task_stat() When reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent without proper RCU protection, which leads to: cpu 0 cpu 1 ----- ----- do_task_stat var = task->real_parent release_task call_rcu(delayed_put_task_struct) task_tgid_nr_ns(var) rcu_read_lock <--- Too late to protect task->real_parent! task_pid_ptr <--- UAF! rcu_read_unlock This patch uses task_ppid_nr_ns() instead of task_tgid_nr_ns() to add proper RCU protection for accessing task->real_parent.

• linux linux kernel (>= 2.6.26 < 5.10.252) • linux linux kernel (>= 5.11 < 5.15.202) • linux linux kernel (>= 5.16 < 6.1.165) • linux linux kernel (>= 6.2 < 6.6.128) • linux linux kernel (>= 6.7 < 6.12.75) • linux linux kernel (>= 6.13 < 6.18.14) • linux linux kernel (>= 6.19 < 6.19.4)