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- /* 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/sched/user.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 <linux/uaccess.h>
- #include <keys/request_key_auth-type.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 = REFCOUNT_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 = GLOBAL_ROOT_UID,
- };
- /*
- * 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;
- key_perm_t user_keyring_perm;
- char buf[20];
- int ret;
- uid_t uid;
- user_keyring_perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL;
- cred = current_cred();
- user = cred->user;
- uid = from_kuid(cred->user_ns, user->uid);
- kenter("%p{%u}", 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", uid);
- uid_keyring = find_keyring_by_name(buf, true);
- if (IS_ERR(uid_keyring)) {
- uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID,
- cred, user_keyring_perm,
- KEY_ALLOC_UID_KEYRING |
- KEY_ALLOC_IN_QUOTA,
- NULL, 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", uid);
- session_keyring = find_keyring_by_name(buf, true);
- if (IS_ERR(session_keyring)) {
- session_keyring =
- keyring_alloc(buf, user->uid, INVALID_GID,
- cred, user_keyring_perm,
- KEY_ALLOC_UID_KEYRING |
- KEY_ALLOC_IN_QUOTA,
- NULL, 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 thread keyring to the given credentials struct if it didn't have
- * one already. This is allowed to overrun the quota.
- *
- * Return: 0 if a thread keyring is now present; -errno on failure.
- */
- int install_thread_keyring_to_cred(struct cred *new)
- {
- struct key *keyring;
- if (new->thread_keyring)
- return 0;
- keyring = keyring_alloc("_tid", new->uid, new->gid, new,
- KEY_POS_ALL | KEY_USR_VIEW,
- KEY_ALLOC_QUOTA_OVERRUN,
- NULL, NULL);
- if (IS_ERR(keyring))
- return PTR_ERR(keyring);
- new->thread_keyring = keyring;
- return 0;
- }
- /*
- * Install a thread keyring to the current task if it didn't have one already.
- *
- * Return: 0 if a thread keyring is now present; -errno on failure.
- */
- static int install_thread_keyring(void)
- {
- struct cred *new;
- int ret;
- new = prepare_creds();
- if (!new)
- return -ENOMEM;
- ret = install_thread_keyring_to_cred(new);
- if (ret < 0) {
- abort_creds(new);
- return ret;
- }
- return commit_creds(new);
- }
- /*
- * Install a process keyring to the given credentials struct if it didn't have
- * one already. This is allowed to overrun the quota.
- *
- * Return: 0 if a process keyring is now present; -errno on failure.
- */
- int install_process_keyring_to_cred(struct cred *new)
- {
- struct key *keyring;
- if (new->process_keyring)
- return 0;
- keyring = keyring_alloc("_pid", new->uid, new->gid, new,
- KEY_POS_ALL | KEY_USR_VIEW,
- KEY_ALLOC_QUOTA_OVERRUN,
- NULL, NULL);
- if (IS_ERR(keyring))
- return PTR_ERR(keyring);
- new->process_keyring = keyring;
- return 0;
- }
- /*
- * Install a process keyring to the current task if it didn't have one already.
- *
- * Return: 0 if a process keyring is now present; -errno on failure.
- */
- 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;
- }
- return commit_creds(new);
- }
- /*
- * Install the given keyring as the session keyring of the given credentials
- * struct, replacing the existing one if any. If the given keyring is NULL,
- * then install a new anonymous session keyring.
- *
- * Return: 0 on success; -errno on failure.
- */
- 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->session_keyring)
- flags = KEY_ALLOC_IN_QUOTA;
- keyring = keyring_alloc("_ses", cred->uid, cred->gid, cred,
- KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ,
- flags, NULL, NULL);
- if (IS_ERR(keyring))
- return PTR_ERR(keyring);
- } else {
- __key_get(keyring);
- }
- /* install the keyring */
- old = cred->session_keyring;
- rcu_assign_pointer(cred->session_keyring, keyring);
- if (old)
- key_put(old);
- return 0;
- }
- /*
- * Install the given keyring as the session keyring of the current task,
- * replacing the existing one if any. If the given keyring is NULL, then
- * install a new anonymous session keyring.
- *
- * Return: 0 on success; -errno on failure.
- */
- 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, keyring);
- 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 keyring_search_context *ctx)
- {
- 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 (ctx->cred->thread_keyring) {
- key_ref = keyring_search_aux(
- make_key_ref(ctx->cred->thread_keyring, 1), ctx);
- if (!IS_ERR(key_ref))
- goto found;
- switch (PTR_ERR(key_ref)) {
- case -EAGAIN: /* no key */
- case -ENOKEY: /* negative key */
- ret = key_ref;
- break;
- default:
- err = key_ref;
- break;
- }
- }
- /* search the process keyring second */
- if (ctx->cred->process_keyring) {
- key_ref = keyring_search_aux(
- make_key_ref(ctx->cred->process_keyring, 1), ctx);
- 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 (ctx->cred->session_keyring) {
- rcu_read_lock();
- key_ref = keyring_search_aux(
- make_key_ref(rcu_dereference(ctx->cred->session_keyring), 1),
- ctx);
- 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 (ctx->cred->user->session_keyring) {
- key_ref = keyring_search_aux(
- make_key_ref(ctx->cred->user->session_keyring, 1),
- ctx);
- 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 keyring_search_context *ctx)
- {
- struct request_key_auth *rka;
- key_ref_t key_ref, ret = ERR_PTR(-EACCES), err;
- might_sleep();
- key_ref = search_my_process_keyrings(ctx);
- 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 (ctx->cred->request_key_auth &&
- ctx->cred == current_cred() &&
- ctx->index_key.type != &key_type_request_key_auth
- ) {
- const struct cred *cred = ctx->cred;
- /* defend against the auth key being revoked */
- down_read(&cred->request_key_auth->sem);
- if (key_validate(ctx->cred->request_key_auth) == 0) {
- rka = ctx->cred->request_key_auth->payload.data[0];
- ctx->cred = rka->cred;
- key_ref = search_process_keyrings(ctx);
- ctx->cred = 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.
- */
- bool lookup_user_key_possessed(const struct key *key,
- const struct key_match_data *match_data)
- {
- return key == match_data->raw_data;
- }
- /*
- * 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 keyring_search_context ctx = {
- .match_data.cmp = lookup_user_key_possessed,
- .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
- .flags = KEYRING_SEARCH_NO_STATE_CHECK,
- };
- struct request_key_auth *rka;
- struct key *key;
- key_ref_t key_ref, skey_ref;
- int ret;
- try_again:
- ctx.cred = get_current_cred();
- key_ref = ERR_PTR(-ENOKEY);
- switch (id) {
- case KEY_SPEC_THREAD_KEYRING:
- if (!ctx.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 = ctx.cred->thread_keyring;
- __key_get(key);
- key_ref = make_key_ref(key, 1);
- break;
- case KEY_SPEC_PROCESS_KEYRING:
- if (!ctx.cred->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 = ctx.cred->process_keyring;
- __key_get(key);
- key_ref = make_key_ref(key, 1);
- break;
- case KEY_SPEC_SESSION_KEYRING:
- if (!ctx.cred->session_keyring) {
- /* always install a session keyring upon access if one
- * doesn't exist yet */
- ret = install_user_keyrings();
- if (ret < 0)
- goto error;
- if (lflags & KEY_LOOKUP_CREATE)
- ret = join_session_keyring(NULL);
- else
- ret = install_session_keyring(
- ctx.cred->user->session_keyring);
- if (ret < 0)
- goto error;
- goto reget_creds;
- } else if (ctx.cred->session_keyring ==
- ctx.cred->user->session_keyring &&
- lflags & KEY_LOOKUP_CREATE) {
- ret = join_session_keyring(NULL);
- if (ret < 0)
- goto error;
- goto reget_creds;
- }
- rcu_read_lock();
- key = rcu_dereference(ctx.cred->session_keyring);
- __key_get(key);
- rcu_read_unlock();
- key_ref = make_key_ref(key, 1);
- break;
- case KEY_SPEC_USER_KEYRING:
- if (!ctx.cred->user->uid_keyring) {
- ret = install_user_keyrings();
- if (ret < 0)
- goto error;
- }
- key = ctx.cred->user->uid_keyring;
- __key_get(key);
- key_ref = make_key_ref(key, 1);
- break;
- case KEY_SPEC_USER_SESSION_KEYRING:
- if (!ctx.cred->user->session_keyring) {
- ret = install_user_keyrings();
- if (ret < 0)
- goto error;
- }
- key = ctx.cred->user->session_keyring;
- __key_get(key);
- 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 = ctx.cred->request_key_auth;
- if (!key)
- goto error;
- __key_get(key);
- key_ref = make_key_ref(key, 1);
- break;
- case KEY_SPEC_REQUESTOR_KEYRING:
- if (!ctx.cred->request_key_auth)
- goto error;
- down_read(&ctx.cred->request_key_auth->sem);
- if (test_bit(KEY_FLAG_REVOKED,
- &ctx.cred->request_key_auth->flags)) {
- key_ref = ERR_PTR(-EKEYREVOKED);
- key = NULL;
- } else {
- rka = ctx.cred->request_key_auth->payload.data[0];
- key = rka->dest_keyring;
- __key_get(key);
- }
- up_read(&ctx.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 */
- ctx.index_key.type = key->type;
- ctx.index_key.description = key->description;
- ctx.index_key.desc_len = strlen(key->description);
- ctx.match_data.raw_data = key;
- kdebug("check possessed");
- skey_ref = search_process_keyrings(&ctx);
- kdebug("possessed=%p", skey_ref);
- 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) &&
- key_read_state(key) == KEY_IS_UNINSTANTIATED)
- goto invalid_key;
- /* check the permissions */
- ret = key_task_permission(key_ref, ctx.cred, perm);
- if (ret < 0)
- goto invalid_key;
- key->last_used_at = current_kernel_time().tv_sec;
- error:
- put_cred(ctx.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(ctx.cred);
- goto try_again;
- }
- EXPORT_SYMBOL(lookup_user_key);
- /*
- * 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;
- 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->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_POS_ALL | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_LINK,
- KEY_ALLOC_IN_QUOTA, NULL, NULL);
- if (IS_ERR(keyring)) {
- ret = PTR_ERR(keyring);
- goto error2;
- }
- } else if (IS_ERR(keyring)) {
- ret = PTR_ERR(keyring);
- goto error2;
- } else if (keyring == new->session_keyring) {
- ret = 0;
- goto error3;
- }
- /* we've got a keyring - now to install it */
- ret = install_session_keyring_to_cred(new, keyring);
- if (ret < 0)
- goto error3;
- commit_creds(new);
- mutex_unlock(&key_session_mutex);
- ret = keyring->serial;
- key_put(keyring);
- okay:
- return ret;
- error3:
- key_put(keyring);
- 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_change_session_keyring(struct callback_head *twork)
- {
- const struct cred *old = current_cred();
- struct cred *new = container_of(twork, struct cred, rcu);
- if (unlikely(current->flags & PF_EXITING)) {
- put_cred(new);
- return;
- }
- 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 = get_user_ns(old->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_ambient = old->cap_ambient;
- new->cap_bset = old->cap_bset;
- new->jit_keyring = old->jit_keyring;
- new->thread_keyring = key_get(old->thread_keyring);
- new->process_keyring = key_get(old->process_keyring);
- security_transfer_creds(new, old);
- commit_creds(new);
- }
- /*
- * Make sure that root's user and user-session keyrings exist.
- */
- static int __init init_root_keyring(void)
- {
- return install_user_keyrings();
- }
- late_initcall(init_root_keyring);
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