Unverified Commit a71e4f10 authored by Christian Brauner's avatar Christian Brauner
Browse files

pidfs: simplify PIDFD_GET_<type>_NAMESPACE ioctls 

We have reworked namespaces sufficiently that all this special-casing
shouldn't be needed anymore

Link: https://patch.msgid.link/20251117-eidesstattlich-apotheke-36d2e644079f@brauner


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent cc7d6c65

fs/pidfs.c

+36 −39
Original line number Diff line number Diff line
@@ -454,7 +454,6 @@ static long pidfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
	struct task_struct *task __free(put_task) = NULL;

	struct nsproxy *nsp __free(put_nsproxy) = NULL;

	struct ns_common *ns_common = NULL;

	struct pid_namespace *pid_ns;



	if (!pidfs_ioctl_valid(cmd))

		return -ENOIOCTLCMD;
@@ -496,66 +495,64 @@ static long pidfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
	switch (cmd) {

	/* Namespaces that hang of nsproxy. */

	case PIDFD_GET_CGROUP_NAMESPACE:

		if (IS_ENABLED(CONFIG_CGROUPS)) {

			get_cgroup_ns(nsp->cgroup_ns);

		if (!ns_ref_get(nsp->cgroup_ns))

			break;

		ns_common = to_ns_common(nsp->cgroup_ns);

		}

		break;

	case PIDFD_GET_IPC_NAMESPACE:

		if (IS_ENABLED(CONFIG_IPC_NS)) {

			get_ipc_ns(nsp->ipc_ns);

		if (!ns_ref_get(nsp->ipc_ns))

			break;

		ns_common = to_ns_common(nsp->ipc_ns);

		}

		break;

	case PIDFD_GET_MNT_NAMESPACE:

		get_mnt_ns(nsp->mnt_ns);

		if (!ns_ref_get(nsp->mnt_ns))

			break;

		ns_common = to_ns_common(nsp->mnt_ns);

		break;

	case PIDFD_GET_NET_NAMESPACE:

		if (IS_ENABLED(CONFIG_NET_NS)) {

		if (!ns_ref_get(nsp->net_ns))

			break;

		ns_common = to_ns_common(nsp->net_ns);

			get_net_ns(ns_common);

		}

		break;

	case PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE:

		if (IS_ENABLED(CONFIG_PID_NS)) {

			get_pid_ns(nsp->pid_ns_for_children);

		if (!ns_ref_get(nsp->pid_ns_for_children))

			break;

		ns_common = to_ns_common(nsp->pid_ns_for_children);

		}

		break;

	case PIDFD_GET_TIME_NAMESPACE:

		if (IS_ENABLED(CONFIG_TIME_NS)) {

			get_time_ns(nsp->time_ns);

		if (!ns_ref_get(nsp->time_ns))

			break;

		ns_common = to_ns_common(nsp->time_ns);

		}

		break;

	case PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE:

		if (IS_ENABLED(CONFIG_TIME_NS)) {

			get_time_ns(nsp->time_ns_for_children);

		if (!ns_ref_get(nsp->time_ns_for_children))

			break;

		ns_common = to_ns_common(nsp->time_ns_for_children);

		}

		break;

	case PIDFD_GET_UTS_NAMESPACE:

		if (IS_ENABLED(CONFIG_UTS_NS)) {

			get_uts_ns(nsp->uts_ns);

		if (!ns_ref_get(nsp->uts_ns))

			break;

		ns_common = to_ns_common(nsp->uts_ns);

		}

		break;

	/* Namespaces that don't hang of nsproxy. */

	case PIDFD_GET_USER_NAMESPACE:

		if (IS_ENABLED(CONFIG_USER_NS)) {

			rcu_read_lock();

			ns_common = to_ns_common(get_user_ns(task_cred_xxx(task, user_ns)));

			rcu_read_unlock();

		scoped_guard(rcu) {

			struct user_namespace *user_ns;



			user_ns = task_cred_xxx(task, user_ns);

			if (!ns_ref_get(user_ns))

				break;

			ns_common = to_ns_common(user_ns);

		}

		break;

	case PIDFD_GET_PID_NAMESPACE:

		if (IS_ENABLED(CONFIG_PID_NS)) {

			rcu_read_lock();

		scoped_guard(rcu) {

			struct pid_namespace *pid_ns;



			pid_ns = task_active_pid_ns(task);

			if (pid_ns)

				ns_common = to_ns_common(get_pid_ns(pid_ns));

			rcu_read_unlock();

			if (!ns_ref_get(pid_ns))

				break;

			ns_common = to_ns_common(pid_ns);

		}

		break;

	default: