linux-imx

// SPDX-License-Identifier: GPL-2.0-or-later

/* Task credentials management - see Documentation/security/credentials.rst

 *

 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.

 * Written by David Howells (dhowells@redhat.com)

 */

#include <linux/export.h>

#include <linux/cred.h>

#include <linux/slab.h>

#include <linux/sched.h>

#include <linux/sched/coredump.h>

#include <linux/key.h>

#include <linux/keyctl.h>

#include <linux/init_task.h>

#include <linux/security.h>

#include <linux/binfmts.h>

#include <linux/cn_proc.h>

#include <linux/uidgid.h>

​

#if 0

#define kdebug(FMT, ...)                        \

    printk("[%-5.5s%5u] " FMT "\n",                 \

           current->comm, current->pid, ##__VA_ARGS__)

#else

#define kdebug(FMT, ...)                        \

do {                                    \

    if (0)                              \

        no_printk("[%-5.5s%5u] " FMT "\n",          \

              current->comm, current->pid, ##__VA_ARGS__);  \

} while (0)

#endif

​

static struct kmem_cache *cred_jar;

​

/* init to 2 - one for init_task, one to ensure it is never freed */

struct group_info init_groups = { .usage = ATOMIC_INIT(2) };

​

/*

 * The initial credentials for the initial task

 */

struct cred init_cred = {

    .usage          = ATOMIC_INIT(4),

#ifdef CONFIG_DEBUG_CREDENTIALS

    .subscribers        = ATOMIC_INIT(2),

    .magic          = CRED_MAGIC,

#endif

    .uid            = GLOBAL_ROOT_UID,

    .gid            = GLOBAL_ROOT_GID,

    .suid           = GLOBAL_ROOT_UID,

    .sgid           = GLOBAL_ROOT_GID,

    .euid           = GLOBAL_ROOT_UID,

    .egid           = GLOBAL_ROOT_GID,

    .fsuid          = GLOBAL_ROOT_UID,

    .fsgid          = GLOBAL_ROOT_GID,

    .securebits     = SECUREBITS_DEFAULT,

    .cap_inheritable    = CAP_EMPTY_SET,

    .cap_permitted      = CAP_FULL_SET,

    .cap_effective      = CAP_FULL_SET,

    .cap_bset       = CAP_FULL_SET,

    .user           = INIT_USER,

    .user_ns        = &init_user_ns,

    .group_info     = &init_groups,

};

​

static inline void set_cred_subscribers(struct cred *cred, int n)

{

#ifdef CONFIG_DEBUG_CREDENTIALS

    atomic_set(&cred->subscribers, n);

#endif

}

​

static inline int read_cred_subscribers(const struct cred *cred)

{

#ifdef CONFIG_DEBUG_CREDENTIALS

    return atomic_read(&cred->subscribers);

#else

    return 0;

#endif

}

​

static inline void alter_cred_subscribers(const struct cred *_cred, int n)

{

#ifdef CONFIG_DEBUG_CREDENTIALS

    struct cred *cred = (struct cred *) _cred;

​

    atomic_add(n, &cred->subscribers);

#endif

}

​

/*

 * The RCU callback to actually dispose of a set of credentials

 */