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074d589895
The 'struct key' will use 'time_t' which we try to remove in the kernel, since 'time_t' is not year 2038 safe on 32bit systems. Also the 'struct keyring_search_context' will use 'timespec' type to record current time, which is also not year 2038 safe on 32bit systems. Thus this patch replaces 'time_t' with 'time64_t' which is year 2038 safe for 'struct key', and replace 'timespec' with 'time64_t' for the 'struct keyring_search_context', since we only look at the the seconds part of 'timespec' variable. Moreover we also change the codes where using the 'time_t' and 'timespec', and we can get current time by ktime_get_real_seconds() instead of current_kernel_time(), and use 'TIME64_MAX' macro to initialize the 'time64_t' type variable. Especially in proc.c file, we have replaced 'unsigned long' and 'timespec' type with 'u64' and 'time64_t' type to save the timeout value, which means user will get one 'u64' type timeout value by issuing proc_keys_show() function. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com>
891 lines
21 KiB
C
891 lines
21 KiB
C
/* Manage a process's keyrings
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*
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* Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/sched/user.h>
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#include <linux/keyctl.h>
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#include <linux/fs.h>
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#include <linux/err.h>
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#include <linux/mutex.h>
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#include <linux/security.h>
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#include <linux/user_namespace.h>
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#include <linux/uaccess.h>
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#include "internal.h"
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/* Session keyring create vs join semaphore */
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static DEFINE_MUTEX(key_session_mutex);
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/* User keyring creation semaphore */
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static DEFINE_MUTEX(key_user_keyring_mutex);
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/* The root user's tracking struct */
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struct key_user root_key_user = {
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.usage = REFCOUNT_INIT(3),
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.cons_lock = __MUTEX_INITIALIZER(root_key_user.cons_lock),
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.lock = __SPIN_LOCK_UNLOCKED(root_key_user.lock),
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.nkeys = ATOMIC_INIT(2),
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.nikeys = ATOMIC_INIT(2),
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.uid = GLOBAL_ROOT_UID,
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};
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/*
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* Install the user and user session keyrings for the current process's UID.
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*/
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int install_user_keyrings(void)
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{
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struct user_struct *user;
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const struct cred *cred;
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struct key *uid_keyring, *session_keyring;
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key_perm_t user_keyring_perm;
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char buf[20];
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int ret;
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uid_t uid;
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user_keyring_perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL;
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cred = current_cred();
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user = cred->user;
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uid = from_kuid(cred->user_ns, user->uid);
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kenter("%p{%u}", user, uid);
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if (user->uid_keyring && user->session_keyring) {
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kleave(" = 0 [exist]");
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return 0;
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}
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mutex_lock(&key_user_keyring_mutex);
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ret = 0;
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if (!user->uid_keyring) {
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/* get the UID-specific keyring
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* - there may be one in existence already as it may have been
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* pinned by a session, but the user_struct pointing to it
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* may have been destroyed by setuid */
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sprintf(buf, "_uid.%u", uid);
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uid_keyring = find_keyring_by_name(buf, true);
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if (IS_ERR(uid_keyring)) {
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uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID,
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cred, user_keyring_perm,
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KEY_ALLOC_UID_KEYRING |
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KEY_ALLOC_IN_QUOTA,
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NULL, NULL);
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if (IS_ERR(uid_keyring)) {
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ret = PTR_ERR(uid_keyring);
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goto error;
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}
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}
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/* get a default session keyring (which might also exist
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* already) */
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sprintf(buf, "_uid_ses.%u", uid);
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session_keyring = find_keyring_by_name(buf, true);
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if (IS_ERR(session_keyring)) {
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session_keyring =
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keyring_alloc(buf, user->uid, INVALID_GID,
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cred, user_keyring_perm,
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KEY_ALLOC_UID_KEYRING |
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KEY_ALLOC_IN_QUOTA,
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NULL, NULL);
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if (IS_ERR(session_keyring)) {
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ret = PTR_ERR(session_keyring);
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goto error_release;
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}
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/* we install a link from the user session keyring to
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* the user keyring */
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ret = key_link(session_keyring, uid_keyring);
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if (ret < 0)
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goto error_release_both;
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}
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/* install the keyrings */
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user->uid_keyring = uid_keyring;
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user->session_keyring = session_keyring;
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}
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mutex_unlock(&key_user_keyring_mutex);
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kleave(" = 0");
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return 0;
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error_release_both:
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key_put(session_keyring);
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error_release:
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key_put(uid_keyring);
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error:
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mutex_unlock(&key_user_keyring_mutex);
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kleave(" = %d", ret);
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return ret;
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}
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/*
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* Install a thread keyring to the given credentials struct if it didn't have
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* one already. This is allowed to overrun the quota.
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*
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* Return: 0 if a thread keyring is now present; -errno on failure.
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*/
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int install_thread_keyring_to_cred(struct cred *new)
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{
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struct key *keyring;
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if (new->thread_keyring)
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return 0;
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keyring = keyring_alloc("_tid", new->uid, new->gid, new,
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KEY_POS_ALL | KEY_USR_VIEW,
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KEY_ALLOC_QUOTA_OVERRUN,
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NULL, NULL);
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if (IS_ERR(keyring))
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return PTR_ERR(keyring);
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new->thread_keyring = keyring;
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return 0;
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}
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/*
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* Install a thread keyring to the current task if it didn't have one already.
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*
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* Return: 0 if a thread keyring is now present; -errno on failure.
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*/
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static int install_thread_keyring(void)
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{
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struct cred *new;
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int ret;
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new = prepare_creds();
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if (!new)
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return -ENOMEM;
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ret = install_thread_keyring_to_cred(new);
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if (ret < 0) {
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abort_creds(new);
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return ret;
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}
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return commit_creds(new);
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}
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/*
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* Install a process keyring to the given credentials struct if it didn't have
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* one already. This is allowed to overrun the quota.
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*
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* Return: 0 if a process keyring is now present; -errno on failure.
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*/
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int install_process_keyring_to_cred(struct cred *new)
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{
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struct key *keyring;
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if (new->process_keyring)
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return 0;
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keyring = keyring_alloc("_pid", new->uid, new->gid, new,
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KEY_POS_ALL | KEY_USR_VIEW,
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KEY_ALLOC_QUOTA_OVERRUN,
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NULL, NULL);
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if (IS_ERR(keyring))
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return PTR_ERR(keyring);
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new->process_keyring = keyring;
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return 0;
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}
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/*
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* Install a process keyring to the current task if it didn't have one already.
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*
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* Return: 0 if a process keyring is now present; -errno on failure.
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*/
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static int install_process_keyring(void)
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{
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struct cred *new;
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int ret;
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new = prepare_creds();
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if (!new)
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return -ENOMEM;
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ret = install_process_keyring_to_cred(new);
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if (ret < 0) {
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abort_creds(new);
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return ret;
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}
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return commit_creds(new);
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}
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/*
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* Install the given keyring as the session keyring of the given credentials
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* struct, replacing the existing one if any. If the given keyring is NULL,
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* then install a new anonymous session keyring.
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*
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* Return: 0 on success; -errno on failure.
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*/
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int install_session_keyring_to_cred(struct cred *cred, struct key *keyring)
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{
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unsigned long flags;
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struct key *old;
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might_sleep();
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/* create an empty session keyring */
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if (!keyring) {
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flags = KEY_ALLOC_QUOTA_OVERRUN;
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if (cred->session_keyring)
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flags = KEY_ALLOC_IN_QUOTA;
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keyring = keyring_alloc("_ses", cred->uid, cred->gid, cred,
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KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ,
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flags, NULL, NULL);
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if (IS_ERR(keyring))
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return PTR_ERR(keyring);
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} else {
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__key_get(keyring);
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}
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/* install the keyring */
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old = cred->session_keyring;
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rcu_assign_pointer(cred->session_keyring, keyring);
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if (old)
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key_put(old);
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return 0;
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}
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/*
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* Install the given keyring as the session keyring of the current task,
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* replacing the existing one if any. If the given keyring is NULL, then
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* install a new anonymous session keyring.
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*
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* Return: 0 on success; -errno on failure.
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*/
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static int install_session_keyring(struct key *keyring)
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{
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struct cred *new;
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int ret;
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new = prepare_creds();
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if (!new)
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return -ENOMEM;
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ret = install_session_keyring_to_cred(new, keyring);
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if (ret < 0) {
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abort_creds(new);
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return ret;
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}
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return commit_creds(new);
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}
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/*
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* Handle the fsuid changing.
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*/
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void key_fsuid_changed(struct task_struct *tsk)
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{
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/* update the ownership of the thread keyring */
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BUG_ON(!tsk->cred);
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if (tsk->cred->thread_keyring) {
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down_write(&tsk->cred->thread_keyring->sem);
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tsk->cred->thread_keyring->uid = tsk->cred->fsuid;
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up_write(&tsk->cred->thread_keyring->sem);
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}
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}
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/*
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* Handle the fsgid changing.
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*/
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void key_fsgid_changed(struct task_struct *tsk)
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{
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/* update the ownership of the thread keyring */
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BUG_ON(!tsk->cred);
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if (tsk->cred->thread_keyring) {
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down_write(&tsk->cred->thread_keyring->sem);
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tsk->cred->thread_keyring->gid = tsk->cred->fsgid;
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up_write(&tsk->cred->thread_keyring->sem);
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}
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}
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/*
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* Search the process keyrings attached to the supplied cred for the first
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* matching key.
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*
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* The search criteria are the type and the match function. The description is
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* given to the match function as a parameter, but doesn't otherwise influence
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* the search. Typically the match function will compare the description
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* parameter to the key's description.
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*
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* This can only search keyrings that grant Search permission to the supplied
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* credentials. Keyrings linked to searched keyrings will also be searched if
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* they grant Search permission too. Keys can only be found if they grant
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* Search permission to the credentials.
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*
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* Returns a pointer to the key with the key usage count incremented if
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* successful, -EAGAIN if we didn't find any matching key or -ENOKEY if we only
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* matched negative keys.
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*
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* In the case of a successful return, the possession attribute is set on the
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* returned key reference.
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*/
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key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx)
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{
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key_ref_t key_ref, ret, err;
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/* we want to return -EAGAIN or -ENOKEY if any of the keyrings were
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* searchable, but we failed to find a key or we found a negative key;
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* otherwise we want to return a sample error (probably -EACCES) if
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* none of the keyrings were searchable
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*
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* in terms of priority: success > -ENOKEY > -EAGAIN > other error
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*/
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key_ref = NULL;
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ret = NULL;
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err = ERR_PTR(-EAGAIN);
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/* search the thread keyring first */
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if (ctx->cred->thread_keyring) {
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key_ref = keyring_search_aux(
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make_key_ref(ctx->cred->thread_keyring, 1), ctx);
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if (!IS_ERR(key_ref))
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goto found;
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switch (PTR_ERR(key_ref)) {
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case -EAGAIN: /* no key */
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case -ENOKEY: /* negative key */
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ret = key_ref;
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break;
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default:
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err = key_ref;
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break;
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}
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}
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/* search the process keyring second */
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if (ctx->cred->process_keyring) {
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key_ref = keyring_search_aux(
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make_key_ref(ctx->cred->process_keyring, 1), ctx);
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if (!IS_ERR(key_ref))
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goto found;
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switch (PTR_ERR(key_ref)) {
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case -EAGAIN: /* no key */
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if (ret)
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break;
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case -ENOKEY: /* negative key */
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ret = key_ref;
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break;
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default:
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err = key_ref;
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break;
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}
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}
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/* search the session keyring */
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if (ctx->cred->session_keyring) {
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rcu_read_lock();
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key_ref = keyring_search_aux(
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make_key_ref(rcu_dereference(ctx->cred->session_keyring), 1),
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ctx);
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rcu_read_unlock();
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if (!IS_ERR(key_ref))
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goto found;
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switch (PTR_ERR(key_ref)) {
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case -EAGAIN: /* no key */
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if (ret)
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break;
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case -ENOKEY: /* negative key */
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ret = key_ref;
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break;
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default:
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err = key_ref;
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break;
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}
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}
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/* or search the user-session keyring */
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else if (ctx->cred->user->session_keyring) {
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key_ref = keyring_search_aux(
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make_key_ref(ctx->cred->user->session_keyring, 1),
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ctx);
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if (!IS_ERR(key_ref))
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goto found;
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switch (PTR_ERR(key_ref)) {
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case -EAGAIN: /* no key */
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if (ret)
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break;
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case -ENOKEY: /* negative key */
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ret = key_ref;
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break;
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default:
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err = key_ref;
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break;
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}
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}
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/* no key - decide on the error we're going to go for */
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key_ref = ret ? ret : err;
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found:
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return key_ref;
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}
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/*
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* Search the process keyrings attached to the supplied cred for the first
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* matching key in the manner of search_my_process_keyrings(), but also search
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* the keys attached to the assumed authorisation key using its credentials if
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* one is available.
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*
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* Return same as search_my_process_keyrings().
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*/
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key_ref_t search_process_keyrings(struct keyring_search_context *ctx)
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{
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struct request_key_auth *rka;
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key_ref_t key_ref, ret = ERR_PTR(-EACCES), err;
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might_sleep();
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key_ref = search_my_process_keyrings(ctx);
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if (!IS_ERR(key_ref))
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goto found;
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err = key_ref;
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/* if this process has an instantiation authorisation key, then we also
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* search the keyrings of the process mentioned there
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* - we don't permit access to request_key auth keys via this method
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*/
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if (ctx->cred->request_key_auth &&
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ctx->cred == current_cred() &&
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ctx->index_key.type != &key_type_request_key_auth
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) {
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const struct cred *cred = ctx->cred;
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/* defend against the auth key being revoked */
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down_read(&cred->request_key_auth->sem);
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if (key_validate(ctx->cred->request_key_auth) == 0) {
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rka = ctx->cred->request_key_auth->payload.data[0];
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ctx->cred = rka->cred;
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key_ref = search_process_keyrings(ctx);
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ctx->cred = cred;
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up_read(&cred->request_key_auth->sem);
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if (!IS_ERR(key_ref))
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goto found;
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ret = key_ref;
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} else {
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up_read(&cred->request_key_auth->sem);
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}
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}
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/* no key - decide on the error we're going to go for */
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if (err == ERR_PTR(-ENOKEY) || ret == ERR_PTR(-ENOKEY))
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key_ref = ERR_PTR(-ENOKEY);
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else if (err == ERR_PTR(-EACCES))
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key_ref = ret;
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else
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key_ref = err;
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found:
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return key_ref;
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}
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/*
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* See if the key we're looking at is the target key.
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*/
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bool lookup_user_key_possessed(const struct key *key,
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const struct key_match_data *match_data)
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{
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return key == match_data->raw_data;
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}
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/*
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* Look up a key ID given us by userspace with a given permissions mask to get
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* the key it refers to.
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*
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* Flags can be passed to request that special keyrings be created if referred
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* to directly, to permit partially constructed keys to be found and to skip
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* validity and permission checks on the found key.
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*
|
|
* 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 = ktime_get_real_seconds();
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* 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);
|