![Tejun Heo](/assets/img/avatar_default.png)
percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
819 lines
18 KiB
C
819 lines
18 KiB
C
/* Management of 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/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 <asm/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 = ATOMIC_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 = 0,
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.user_ns = &init_user_ns,
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};
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/*****************************************************************************/
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/*
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* install user and user session keyrings for a particular 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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char buf[20];
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int ret;
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cred = current_cred();
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user = cred->user;
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kenter("%p{%u}", user, user->uid);
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if (user->uid_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", user->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, (gid_t) -1,
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cred, KEY_ALLOC_IN_QUOTA,
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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", user->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, (gid_t) -1,
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cred, KEY_ALLOC_IN_QUOTA, 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 fresh thread keyring directly to new credentials
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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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keyring = keyring_alloc("_tid", new->uid, new->gid, new,
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KEY_ALLOC_QUOTA_OVERRUN, 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 fresh thread keyring, discarding the old one
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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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BUG_ON(new->thread_keyring);
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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 directly to a credentials struct
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* - returns -EEXIST if there was already a process keyring, 0 if one installed,
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* and other -ve on any other error
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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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int ret;
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if (new->tgcred->process_keyring)
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return -EEXIST;
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keyring = keyring_alloc("_pid", new->uid, new->gid,
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new, KEY_ALLOC_QUOTA_OVERRUN, NULL);
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if (IS_ERR(keyring))
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return PTR_ERR(keyring);
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spin_lock_irq(&new->tgcred->lock);
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if (!new->tgcred->process_keyring) {
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new->tgcred->process_keyring = keyring;
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keyring = NULL;
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ret = 0;
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} else {
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ret = -EEXIST;
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}
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spin_unlock_irq(&new->tgcred->lock);
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key_put(keyring);
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return ret;
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}
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/*
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* make sure a process keyring is installed
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* - we
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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 != -EEXIST ?: 0;
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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 session keyring directly to a credentials struct
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*/
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static int install_session_keyring_to_cred(struct cred *cred,
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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->tgcred->session_keyring)
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flags = KEY_ALLOC_IN_QUOTA;
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keyring = keyring_alloc("_ses", cred->uid, cred->gid,
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cred, flags, 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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atomic_inc(&keyring->usage);
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}
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/* install the keyring */
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spin_lock_irq(&cred->tgcred->lock);
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old = cred->tgcred->session_keyring;
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rcu_assign_pointer(cred->tgcred->session_keyring, keyring);
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spin_unlock_irq(&cred->tgcred->lock);
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/* we're using RCU on the pointer, but there's no point synchronising
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* on it if it didn't previously point to anything */
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if (old) {
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synchronize_rcu();
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key_put(old);
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}
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return 0;
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}
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/*
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* install a session keyring, discarding the old one
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* - if a keyring is not supplied, an empty one is invented
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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, NULL);
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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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/*
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* the filesystem user ID changed
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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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} /* end key_fsuid_changed() */
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/*****************************************************************************/
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/*
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* the filesystem group ID changed
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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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} /* end key_fsgid_changed() */
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/*****************************************************************************/
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/*
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* search the process keyrings for the first matching key
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* - we use the supplied match function to see if the description (or other
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* feature of interest) matches
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* - we return -EAGAIN if we didn't find any matching key
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* - we return -ENOKEY if we found only negative matching keys
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*/
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key_ref_t search_process_keyrings(struct key_type *type,
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const void *description,
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key_match_func_t match,
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const struct cred *cred)
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{
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struct request_key_auth *rka;
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key_ref_t key_ref, ret, err;
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might_sleep();
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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 (cred->thread_keyring) {
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key_ref = keyring_search_aux(
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make_key_ref(cred->thread_keyring, 1),
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cred, type, description, match);
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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 process keyring second */
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if (cred->tgcred->process_keyring) {
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key_ref = keyring_search_aux(
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make_key_ref(cred->tgcred->process_keyring, 1),
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cred, type, description, match);
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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 (cred->tgcred->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(
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cred->tgcred->session_keyring),
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1),
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cred, type, description, match);
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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 (cred->user->session_keyring) {
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key_ref = keyring_search_aux(
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make_key_ref(cred->user->session_keyring, 1),
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cred, type, description, match);
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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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/* 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 (cred->request_key_auth &&
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cred == current_cred() &&
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type != &key_type_request_key_auth
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) {
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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(cred->request_key_auth) == 0) {
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rka = cred->request_key_auth->payload.data;
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key_ref = search_process_keyrings(type, description,
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match, rka->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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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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} 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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key_ref = ret ? ret : err;
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found:
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return key_ref;
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} /* end search_process_keyrings() */
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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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static int lookup_user_key_possessed(const struct key *key, const void *target)
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{
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return key == target;
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} /* end lookup_user_key_possessed() */
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/*****************************************************************************/
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/*
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* lookup a key given a key ID from userspace with a given permissions mask
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* - don't create special keyrings unless so requested
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* - partially constructed keys aren't found unless requested
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*/
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key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
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key_perm_t perm)
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{
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struct request_key_auth *rka;
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const struct cred *cred;
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struct key *key;
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key_ref_t key_ref, skey_ref;
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int ret;
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|
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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 = 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 = 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 = 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;
|
|
|
|
} /* end lookup_user_key() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* join the named keyring as the session keyring if possible, or attempt to
|
|
* create a new one of that name if not
|
|
* - if the name is NULL, an empty anonymous keyring is installed instead
|
|
* - named session keyring joining is done with a semaphore held
|
|
*/
|
|
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 when that process resumes userspace on
|
|
* behalf of one of its children
|
|
*/
|
|
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->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);
|
|
}
|