Unverified Commit da664c6d authored Aug 19, 2025 by Christian Brauner

Merge patch series "Improve pid_nr_ns()"

In various places pid_nr_ns() can be called with a NULL pointer.
Fix those up and improve pid_nr_ns() callers.

Link: https://lore.kernel.org/20250802022123.3536934-1-gxxa03070307@gmail.com


Signed-off-by: Christian Brauner <brauner@kernel.org>

parents 8f5ae30d d00f5232

fs/proc/array.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -157,13 +157,11 @@ static inline void task_state(struct seq_file m, struct pid_namespace ns,
		unsigned int max_fds = 0;

		rcu_read_lock();
		ppid = pid_alive(p) ?
		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;

		tracer = ptrace_parent(p);
		if (tracer)
		tpid = task_pid_nr_ns(tracer, ns);

		ppid = task_ppid_nr_ns(p, ns);
		tgid = task_tgid_nr_ns(p, ns);
		ngid = task_numa_group_id(p);
		cred = get_task_cred(p);

kernel/pid.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -491,7 +491,7 @@ pid_t pid_nr_ns(struct pid pid, struct pid_namespace ns)
		struct upid *upid;
		pid_t nr = 0;

		if (pid && ns->level <= pid->level) {
		if (pid && ns && ns->level <= pid->level) {
		upid = &pid->numbers[ns->level];
		if (upid->ns == ns)
		nr = upid->nr;
		@@ -514,6 +514,7 @@ pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
		rcu_read_lock();
		if (!ns)
		ns = task_active_pid_ns(current);
		if (ns)
		nr = pid_nr_ns(rcu_dereference(*task_pid_ptr(task, type)), ns);
		rcu_read_unlock();

kernel/tsacct.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -57,12 +57,11 @@ void bacct_add_tsk(struct user_namespace *user_ns,
		stats->ac_sched = tsk->policy;
		stats->ac_pid = task_pid_nr_ns(tsk, pid_ns);
		stats->ac_tgid = task_tgid_nr_ns(tsk, pid_ns);
		stats->ac_ppid = task_ppid_nr_ns(tsk, pid_ns);
		rcu_read_lock();
		tcred = __task_cred(tsk);
		stats->ac_uid = from_kuid_munged(user_ns, tcred->uid);
		stats->ac_gid = from_kgid_munged(user_ns, tcred->gid);
		stats->ac_ppid = pid_alive(tsk) ?
		task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0;
		rcu_read_unlock();

		task_cputime(tsk, &utime, &stime);