text: /* Manage a process's keyrings
   *
   * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved.
   * Written by David Howells (dhowells@redhat.com)
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version
   * 2 of the License, or (at your option) any later version.
   */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/sched.h>
  #include <linux/keyctl.h>
  #include <linux/fs.h>
  #include <linux/err.h>
  #include <linux/mutex.h>
  #include <linux/security.h>
  #include <linux/user_namespace.h>
  #include <asm/uaccess.h>
  #include "internal.h"
  
  /* Session keyring create vs join semaphore */
  static DEFINE_MUTEX(key_session_mutex);
  
  /* User keyring creation semaphore */
  static DEFINE_MUTEX(key_user_keyring_mutex);
  
  /* The root user's tracking struct */
  struct key_user root_key_user = {
  	.usage		= ATOMIC_INIT(3),
  	.cons_lock	= __MUTEX_INITIALIZER(root_key_user.cons_lock),
  	.lock		= __SPIN_LOCK_UNLOCKED(root_key_user.lock),
  	.nkeys		= ATOMIC_INIT(2),
  	.nikeys		= ATOMIC_INIT(2),
  	.uid		= 0,
  	.user_ns	= &init_user_ns,
  };
  
  /*
   * Install the user and user session keyrings for the current process's UID.
   */
  int install_user_keyrings(void)
  {
  	struct user_struct *user;
  	const struct cred *cred;
  	struct key *uid_keyring, *session_keyring;
  	char buf[20];
  	int ret;
  
  	cred = current_cred();
  	user = cred->user;
  
  	kenter("%p{%u}", user, user->uid);
  
  	if (user->uid_keyring && user->session_keyring) {
  		kleave(" = 0 [exist]");
  		return 0;
  	}
  
  	mutex_lock(&key_user_keyring_mutex);
  	ret = 0;
  
  	if (!user->uid_keyring) {
  		/* get the UID-specific keyring
  		 * - there may be one in existence already as it may have been
  		 *   pinned by a session, but the user_struct pointing to it
  		 *   may have been destroyed by setuid */
  		sprintf(buf, "_uid.%u", user->uid);
  
  		uid_keyring = find_keyring_by_name(buf, true);
  		if (IS_ERR(uid_keyring)) {
  			uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1,
  						    cred, KEY_ALLOC_IN_QUOTA,
  						    NULL);
  			if (IS_ERR(uid_keyring)) {
  				ret = PTR_ERR(uid_keyring);
  				goto error;
  			}
  		}
  
  		/* get a default session keyring (which might also exist
  		 * already) */
  		sprintf(buf, "_uid_ses.%u", user->uid);
  
  		session_keyring = find_keyring_by_name(buf, true);
  		if (IS_ERR(session_keyring)) {
  			session_keyring =
  				keyring_alloc(buf, user->uid, (gid_t) -1,
  					      cred, KEY_ALLOC_IN_QUOTA, NULL);
  			if (IS_ERR(session_keyring)) {
  				ret = PTR_ERR(session_keyring);
  				goto error_release;
  			}
  
  			/* we install a link from the user session keyring to
  			 * the user keyring */
  			ret = key_link(session_keyring, uid_keyring);
  			if (ret < 0)
  				goto error_release_both;
  		}
  
  		/* install the keyrings */
  		user->uid_keyring = uid_keyring;
  		user->session_keyring = session_keyring;
  	}
  
  	mutex_unlock(&key_user_keyring_mutex);
  	kleave(" = 0");
  	return 0;
  
  error_release_both:
  	key_put(session_keyring);
  error_release:
  	key_put(uid_keyring);
  error:
  	mutex_unlock(&key_user_keyring_mutex);
  	kleave(" = %d", ret);
  	return ret;
  }
  
  /*
   * Install a fresh thread keyring directly to new credentials.  This keyring is
   * allowed to overrun the quota.
   */
  int install_thread_keyring_to_cred(struct cred *new)
  {
  	struct key *keyring;
  
  	keyring = keyring_alloc("_tid", new->uid, new->gid, new,
  				KEY_ALLOC_QUOTA_OVERRUN, NULL);
  	if (IS_ERR(keyring))
  		return PTR_ERR(keyring);
  
  	new->thread_keyring = keyring;
  	return 0;
  }
  
  /*
   * Install a fresh thread keyring, discarding the old one.
   */
  static int install_thread_keyring(void)
  {
  	struct cred *new;
  	int ret;
  
  	new = prepare_creds();
  	if (!new)
  		return -ENOMEM;
  
  	BUG_ON(new->thread_keyring);
  
  	ret = install_thread_keyring_to_cred(new);
  	if (ret < 0) {
  		abort_creds(new);
  		return ret;
  	}
  
  	return commit_creds(new);
  }
  
  /*
   * Install a process keyring directly to a credentials struct.
   *
   * Returns -EEXIST if there was already a process keyring, 0 if one installed,
   * and other value on any other error
   */
  int install_process_keyring_to_cred(struct cred *new)
  {
  	struct key *keyring;
  	int ret;
  
  	if (new->tgcred->process_keyring)
  		return -EEXIST;
  
  	keyring = keyring_alloc("_pid", new->uid, new->gid,
  				new, KEY_ALLOC_QUOTA_OVERRUN, NULL);
  	if (IS_ERR(keyring))
  		return PTR_ERR(keyring);
  
  	spin_lock_irq(&new->tgcred->lock);
  	if (!new->tgcred->process_keyring) {
  		new->tgcred->process_keyring = keyring;
  		keyring = NULL;
  		ret = 0;
  	} else {
  		ret = -EEXIST;
  	}
  	spin_unlock_irq(&new->tgcred->lock);
  	key_put(keyring);
  	return ret;
  }
  
  /*
   * Make sure a process keyring is installed for the current process.  The
   * existing process keyring is not replaced.
   *
   * Returns 0 if there is a process keyring by the end of this function, some
   * error otherwise.
   */
  static int install_process_keyring(void)
  {
  	struct cred *new;
  	int ret;
  
  	new = prepare_creds();
  	if (!new)
  		return -ENOMEM;
  
  	ret = install_process_keyring_to_cred(new);
  	if (ret < 0) {
  		abort_creds(new);
  		return ret != -EEXIST ? ret : 0;
  	}
  
  	return commit_creds(new);
  }
  
  /*
   * Install a session keyring directly to a credentials struct.
   */
  int install_session_keyring_to_cred(struct cred *cred, struct key *keyring)
  {
  	unsigned long flags;
  	struct key *old;
  
  	might_sleep();
  
  	/* create an empty session keyring */
  	if (!keyring) {
  		flags = KEY_ALLOC_QUOTA_OVERRUN;
  		if (cred->tgcred->session_keyring)
  			flags = KEY_ALLOC_IN_QUOTA;
  
  		keyring = keyring_alloc("_ses", cred->uid, cred->gid,
  					cred, flags, NULL);
  		if (IS_ERR(keyring))
  			return PTR_ERR(keyring);
  	} else {
  		atomic_inc(&keyring->usage);
  	}
  
  	/* install the keyring */
  	spin_lock_irq(&cred->tgcred->lock);
  	old = cred->tgcred->session_keyring;
  	rcu_assign_pointer(cred->tgcred->session_keyring, keyring);
  	spin_unlock_irq(&cred->tgcred->lock);
  
  	/* we're using RCU on the pointer, but there's no point synchronising
  	 * on it if it didn't previously point to anything */
  	if (old) {
  		synchronize_rcu();
  		key_put(old);
  	}
  
  	return 0;
  }
  
  /*
   * Install a session keyring, discarding the old one.  If a keyring is not
   * supplied, an empty one is invented.
   */
  static int install_session_keyring(struct key *keyring)
  {
  	struct cred *new;
  	int ret;
  
  	new = prepare_creds();
  	if (!new)
  		return -ENOMEM;
  
  	ret = install_session_keyring_to_cred(new, NULL);
  	if (ret < 0) {
  		abort_creds(new);
  		return ret;
  	}
  
  	return commit_creds(new);
  }
  
  /*
   * Handle the fsuid changing.
   */
  void key_fsuid_changed(struct task_struct *tsk)
  {
  	/* update the ownership of the thread keyring */
  	BUG_ON(!tsk->cred);
  	if (tsk->cred->thread_keyring) {
  		down_write(&tsk->cred->thread_keyring->sem);
  		tsk->cred->thread_keyring->uid = tsk->cred->fsuid;
  		up_write(&tsk->cred->thread_keyring->sem);
  	}
  }
  
  /*
   * Handle the fsgid changing.
   */
  void key_fsgid_changed(struct task_struct *tsk)
  {
  	/* update the ownership of the thread keyring */
  	BUG_ON(!tsk->cred);
  	if (tsk->cred->thread_keyring) {
  		down_write(&tsk->cred->thread_keyring->sem);
  		tsk->cred->thread_keyring->gid = tsk->cred->fsgid;
  		up_write(&tsk->cred->thread_keyring->sem);
  	}
  }
  
  /*
   * Search the process keyrings attached to the supplied cred for the first
   * matching key.
   *
   * The search criteria are the type and the match function.  The description is
   * given to the match function as a parameter, but doesn't otherwise influence
   * the search.  Typically the match function will compare the description
   * parameter to the key's description.
   *
   * This can only search keyrings that grant Search permission to the supplied
   * credentials.  Keyrings linked to searched keyrings will also be searched if
   * they grant Search permission too.  Keys can only be found if they grant
   * Search permission to the credentials.
   *
   * Returns a pointer to the key with the key usage count incremented if
   * successful, -EAGAIN if we didn't find any matching key or -ENOKEY if we only
   * matched negative keys.
   *
   * In the case of a successful return, the possession attribute is set on the
   * returned key reference.
   */
  key_ref_t search_my_process_keyrings(struct key_type *type,
  				     const void *description,
  				     key_match_func_t match,
  				     bool no_state_check,
  				     const struct cred *cred)
  {
  	key_ref_t key_ref, ret, err;
  
  	/* we want to return -EAGAIN or -ENOKEY if any of the keyrings were
  	 * searchable, but we failed to find a key or we found a negative key;
  	 * otherwise we want to return a sample error (probably -EACCES) if
  	 * none of the keyrings were searchable
  	 *
  	 * in terms of priority: success > -ENOKEY > -EAGAIN > other error
  	 */
  	key_ref = NULL;
  	ret = NULL;
  	err = ERR_PTR(-EAGAIN);
  
  	/* search the thread keyring first */
  	if (cred->thread_keyring) {
  		key_ref = keyring_search_aux(
  			make_key_ref(cred->thread_keyring, 1),
  			cred, type, description, match, no_state_check);
  		if (!IS_ERR(key_ref))
  			goto found;
  
  		switch (PTR_ERR(key_ref)) {
  		case -EAGAIN: /* no key */
  			if (ret)
  				break;
  		case -ENOKEY: /* negative key */
  			ret = key_ref;
  			break;
  		default:
  			err = key_ref;
  			break;
  		}
  	}
  
  	/* search the process keyring second */
  	if (cred->tgcred->process_keyring) {
  		key_ref = keyring_search_aux(
  			make_key_ref(cred->tgcred->process_keyring, 1),
  			cred, type, description, match, no_state_check);
  		if (!IS_ERR(key_ref))
  			goto found;
  
  		switch (PTR_ERR(key_ref)) {
  		case -EAGAIN: /* no key */
  			if (ret)
  				break;
  		case -ENOKEY: /* negative key */
  			ret = key_ref;
  			break;
  		default:
  			err = key_ref;
  			break;
  		}
  	}
  
  	/* search the session keyring */
  	if (cred->tgcred->session_keyring) {
  		rcu_read_lock();
  		key_ref = keyring_search_aux(
  			make_key_ref(rcu_dereference(
  					     cred->tgcred->session_keyring),
  				     1),
  			cred, type, description, match, no_state_check);
  		rcu_read_unlock();
  
  		if (!IS_ERR(key_ref))
  			goto found;
  
  		switch (PTR_ERR(key_ref)) {
  		case -EAGAIN: /* no key */
  			if (ret)
  				break;
  		case -ENOKEY: /* negative key */
  			ret = key_ref;
  			break;
  		default:
  			err = key_ref;
  			break;
  		}
  	}
  	/* or search the user-session keyring */
  	else if (cred->user->session_keyring) {
  		key_ref = keyring_search_aux(
  			make_key_ref(cred->user->session_keyring, 1),
  			cred, type, description, match, no_state_check);
  		if (!IS_ERR(key_ref))
  			goto found;
  
  		switch (PTR_ERR(key_ref)) {
  		case -EAGAIN: /* no key */
  			if (ret)
  				break;
  		case -ENOKEY: /* negative key */
  			ret = key_ref;
  			break;
  		default:
  			err = key_ref;
  			break;
  		}
  	}
  
  	/* no key - decide on the error we're going to go for */
  	key_ref = ret ? ret : err;
  
  found:
  	return key_ref;
  }
  
  /*
   * Search the process keyrings attached to the supplied cred for the first
   * matching key in the manner of search_my_process_keyrings(), but also search
   * the keys attached to the assumed authorisation key using its credentials if
   * one is available.
   *
   * Return same as search_my_process_keyrings().
   */
  key_ref_t search_process_keyrings(struct key_type *type,
  				  const void *description,
  				  key_match_func_t match,
  				  const struct cred *cred)
  {
  	struct request_key_auth *rka;
  	key_ref_t key_ref, ret = ERR_PTR(-EACCES), err;
  
  	might_sleep();
  
  	key_ref = search_my_process_keyrings(type, description, match,
  					     false, cred);
  	if (!IS_ERR(key_ref))
  		goto found;
  	err = key_ref;
  
  	/* if this process has an instantiation authorisation key, then we also
  	 * search the keyrings of the process mentioned there
  	 * - we don't permit access to request_key auth keys via this method
  	 */
  	if (cred->request_key_auth &&
  	    cred == current_cred() &&
  	    type != &key_type_request_key_auth
  	    ) {
  		/* defend against the auth key being revoked */
  		down_read(&cred->request_key_auth->sem);
  
  		if (key_validate(cred->request_key_auth) == 0) {
  			rka = cred->request_key_auth->payload.data;
  
  			key_ref = search_process_keyrings(type, description,
  							  match, rka->cred);
  
  			up_read(&cred->request_key_auth->sem);
  
  			if (!IS_ERR(key_ref))
  				goto found;
  
  			ret = key_ref;
  		} else {
  			up_read(&cred->request_key_auth->sem);
  		}
  	}
  
  	/* no key - decide on the error we're going to go for */
  	if (err == ERR_PTR(-ENOKEY) || ret == ERR_PTR(-ENOKEY))
  		key_ref = ERR_PTR(-ENOKEY);
  	else if (err == ERR_PTR(-EACCES))
  		key_ref = ret;
  	else
  		key_ref = err;
  
  found:
  	return key_ref;
  }
  
  /*
   * See if the key we're looking at is the target key.
   */
  int lookup_user_key_possessed(const struct key *key, const void *target)
  {
  	return key == target;
  }
  
  /*
   * Look up a key ID given us by userspace with a given permissions mask to get
   * the key it refers to.
   *
   * Flags can be passed to request that special keyrings be created if referred
   * to directly, to permit partially constructed keys to be found and to skip
   * validity and permission checks on the found key.
   *
   * Returns a pointer to the key with an incremented usage count if successful;
   * -EINVAL if the key ID is invalid; -ENOKEY if the key ID does not correspond
   * to a key or the best found key was a negative key; -EKEYREVOKED or
   * -EKEYEXPIRED if the best found key was revoked or expired; -EACCES if the
   * found key doesn't grant the requested permit or the LSM denied access to it;
   * or -ENOMEM if a special keyring couldn't be created.
   *
   * In the case of a successful return, the possession attribute is set on the
   * returned key reference.
   */
  key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
  			  key_perm_t perm)
  {
  	struct request_key_auth *rka;
  	const struct cred *cred;
  	struct key *key;
  	key_ref_t key_ref, skey_ref;
  	int ret;
  
  try_again:
  	cred = get_current_cred();
  	key_ref = ERR_PTR(-ENOKEY);
  
  	switch (id) {
  	case KEY_SPEC_THREAD_KEYRING:
  		if (!cred->thread_keyring) {
  			if (!(lflags & KEY_LOOKUP_CREATE))
  				goto error;
  
  			ret = install_thread_keyring();
  			if (ret < 0) {
  				key_ref = ERR_PTR(ret);
  				goto error;
  			}
  			goto reget_creds;
  		}
  
  		key = cred->thread_keyring;
  		atomic_inc(&key->usage);
  		key_ref = make_key_ref(key, 1);
  		break;
  
  	case KEY_SPEC_PROCESS_KEYRING:
  		if (!cred->tgcred->process_keyring) {
  			if (!(lflags & KEY_LOOKUP_CREATE))
  				goto error;
  
  			ret = install_process_keyring();
  			if (ret < 0) {
  				key_ref = ERR_PTR(ret);
  				goto error;
  			}
  			goto reget_creds;
  		}
  
  		key = cred->tgcred->process_keyring;
  		atomic_inc(&key->usage);
  		key_ref = make_key_ref(key, 1);
  		break;
  
  	case KEY_SPEC_SESSION_KEYRING:
  		if (!cred->tgcred->session_keyring) {
  			/* always install a session keyring upon access if one
  			 * doesn't exist yet */
  			ret = install_user_keyrings();
  			if (ret < 0)
  				goto error;
  			ret = install_session_keyring(
  				cred->user->session_keyring);
  
  			if (ret < 0)
  				goto error;
  			goto reget_creds;
  		}
  
  		rcu_read_lock();
  		key = rcu_dereference(cred->tgcred->session_keyring);
  		atomic_inc(&key->usage);
  		rcu_read_unlock();
  		key_ref = make_key_ref(key, 1);
  		break;
  
  	case KEY_SPEC_USER_KEYRING:
  		if (!cred->user->uid_keyring) {
  			ret = install_user_keyrings();
  			if (ret < 0)
  				goto error;
  		}
  
  		key = cred->user->uid_keyring;
  		atomic_inc(&key->usage);
  		key_ref = make_key_ref(key, 1);
  		break;
  
  	case KEY_SPEC_USER_SESSION_KEYRING:
  		if (!cred->user->session_keyring) {
  			ret = install_user_keyrings();
  			if (ret < 0)
  				goto error;
  		}
  
  		key = cred->user->session_keyring;
  		atomic_inc(&key->usage);
  		key_ref = make_key_ref(key, 1);
  		break;
  
  	case KEY_SPEC_GROUP_KEYRING:
  		/* group keyrings are not yet supported */
  		key_ref = ERR_PTR(-EINVAL);
  		goto error;
  
  	case KEY_SPEC_REQKEY_AUTH_KEY:
  		key = cred->request_key_auth;
  		if (!key)
  			goto error;
  
  		atomic_inc(&key->usage);
  		key_ref = make_key_ref(key, 1);
  		break;
  
  	case KEY_SPEC_REQUESTOR_KEYRING:
  		if (!cred->request_key_auth)
  			goto error;
  
  		down_read(&cred->request_key_auth->sem);
  		if (cred->request_key_auth->flags & KEY_FLAG_REVOKED) {
  			key_ref = ERR_PTR(-EKEYREVOKED);
  			key = NULL;
  		} else {
  			rka = cred->request_key_auth->payload.data;
  			key = rka->dest_keyring;
  			atomic_inc(&key->usage);
  		}
  		up_read(&cred->request_key_auth->sem);
  		if (!key)
  			goto error;
  		key_ref = make_key_ref(key, 1);
  		break;
  
  	default:
  		key_ref = ERR_PTR(-EINVAL);
  		if (id < 1)
  			goto error;
  
  		key = key_lookup(id);
  		if (IS_ERR(key)) {
  			key_ref = ERR_CAST(key);
  			goto error;
  		}
  
  		key_ref = make_key_ref(key, 0);
  
  		/* check to see if we possess the key */
  		skey_ref = search_process_keyrings(key->type, key,
  						   lookup_user_key_possessed,
  						   cred);
  
  		if (!IS_ERR(skey_ref)) {
  			key_put(key);
  			key_ref = skey_ref;
  		}
  
  		break;
  	}
  
  	/* unlink does not use the nominated key in any way, so can skip all
  	 * the permission checks as it is only concerned with the keyring */
  	if (lflags & KEY_LOOKUP_FOR_UNLINK) {
  		ret = 0;
  		goto error;
  	}
  
  	if (!(lflags & KEY_LOOKUP_PARTIAL)) {
  		ret = wait_for_key_construction(key, true);
  		switch (ret) {
  		case -ERESTARTSYS:
  			goto invalid_key;
  		default:
  			if (perm)
  				goto invalid_key;
  		case 0:
  			break;
  		}
  	} else if (perm) {
  		ret = key_validate(key);
  		if (ret < 0)
  			goto invalid_key;
  	}
  
  	ret = -EIO;
  	if (!(lflags & KEY_LOOKUP_PARTIAL) &&
  	    !test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
  		goto invalid_key;
  
  	/* check the permissions */
  	ret = key_task_permission(key_ref, cred, perm);
  	if (ret < 0)
  		goto invalid_key;
  
  error:
  	put_cred(cred);
  	return key_ref;
  
  invalid_key:
  	key_ref_put(key_ref);
  	key_ref = ERR_PTR(ret);
  	goto error;
  
  	/* if we attempted to install a keyring, then it may have caused new
  	 * creds to be installed */
  reget_creds:
  	put_cred(cred);
  	goto try_again;
  }
  
  /*
   * Join the named keyring as the session keyring if possible else attempt to
   * create a new one of that name and join that.
   *
   * If the name is NULL, an empty anonymous keyring will be installed as the
   * session keyring.
   *
   * Named session keyrings are joined with a semaphore held to prevent the
   * keyrings from going away whilst the attempt is made to going them and also
   * to prevent a race in creating compatible session keyrings.
   */
  long join_session_keyring(const char *name)
  {
  	const struct cred *old;
  	struct cred *new;
  	struct key *keyring;
  	long ret, serial;
  
  	/* only permit this if there's a single thread in the thread group -
  	 * this avoids us having to adjust the creds on all threads and risking
  	 * ENOMEM */
  	if (!current_is_single_threaded())
  		return -EMLINK;
  
  	new = prepare_creds();
  	if (!new)
  		return -ENOMEM;
  	old = current_cred();
  
  	/* if no name is provided, install an anonymous keyring */
  	if (!name) {
  		ret = install_session_keyring_to_cred(new, NULL);
  		if (ret < 0)
  			goto error;
  
  		serial = new->tgcred->session_keyring->serial;
  		ret = commit_creds(new);
  		if (ret == 0)
  			ret = serial;
  		goto okay;
  	}
  
  	/* allow the user to join or create a named keyring */
  	mutex_lock(&key_session_mutex);
  
  	/* look for an existing keyring of this name */
  	keyring = find_keyring_by_name(name, false);
  	if (PTR_ERR(keyring) == -ENOKEY) {
  		/* not found - try and create a new one */
  		keyring = keyring_alloc(name, old->uid, old->gid, old,
  					KEY_ALLOC_IN_QUOTA, NULL);
  		if (IS_ERR(keyring)) {
  			ret = PTR_ERR(keyring);
  			goto error2;
  		}
  	} else if (IS_ERR(keyring)) {
  		ret = PTR_ERR(keyring);
  		goto error2;
  	}
  
  	/* we've got a keyring - now to install it */
  	ret = install_session_keyring_to_cred(new, keyring);
  	if (ret < 0)
  		goto error2;
  
  	commit_creds(new);
  	mutex_unlock(&key_session_mutex);
  
  	ret = keyring->serial;
  	key_put(keyring);
  okay:
  	return ret;
  
  error2:
  	mutex_unlock(&key_session_mutex);
  error:
  	abort_creds(new);
  	return ret;
  }
  
  /*
   * Replace a process's session keyring on behalf of one of its children when
   * the target  process is about to resume userspace execution.
   */
  void key_replace_session_keyring(void)
  {
  	const struct cred *old;
  	struct cred *new;
  
  	if (!current->replacement_session_keyring)
  		return;
  
  	write_lock_irq(&tasklist_lock);
  	new = current->replacement_session_keyring;
  	current->replacement_session_keyring = NULL;
  	write_unlock_irq(&tasklist_lock);
  
  	if (!new)
  		return;
  
  	old = current_cred();
  	new->  uid	= old->  uid;
  	new-> euid	= old-> euid;
  	new-> suid	= old-> suid;
  	new->fsuid	= old->fsuid;
  	new->  gid	= old->  gid;
  	new-> egid	= old-> egid;
  	new-> sgid	= old-> sgid;
  	new->fsgid	= old->fsgid;
  	new->user	= get_uid(old->user);
  	new->user_ns	= new->user->user_ns;
  	new->group_info	= get_group_info(old->group_info);
  
  	new->securebits	= old->securebits;
  	new->cap_inheritable	= old->cap_inheritable;
  	new->cap_permitted	= old->cap_permitted;
  	new->cap_effective	= old->cap_effective;
  	new->cap_bset		= old->cap_bset;
  
  	new->jit_keyring	= old->jit_keyring;
  	new->thread_keyring	= key_get(old->thread_keyring);
  	new->tgcred->tgid	= old->tgcred->tgid;
  	new->tgcred->process_keyring = key_get(old->tgcred->process_keyring);
  
  	security_transfer_creds(new, old);
  
  	commit_creds(new);
  }
  