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selinuxfs.c
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/* Updated: Karl MacMillan <[email protected]>
*
* Added conditional policy language extensions
*
* Updated: Hewlett-Packard <[email protected]>
*
* Added support for the policy capability bitmap
*
* Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
* Copyright (C) 2003 - 2004 Tresys Technology, LLC
* Copyright (C) 2004 Red Hat, Inc., James Morris <[email protected]>
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*/
#include <linux/kernel.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/mutex.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/security.h>
#include <linux/major.h>
#include <linux/seq_file.h>
#include <linux/percpu.h>
#include <linux/audit.h>
#include <asm/uaccess.h>
/* selinuxfs pseudo filesystem for exporting the security policy API.
Based on the proc code and the fs/nfsd/nfsctl.c code. */
#include "flask.h"
#include "avc.h"
#include "avc_ss.h"
#include "security.h"
#include "objsec.h"
#include "conditional.h"
/* Policy capability filenames */
static char *policycap_names[] = {
"network_peer_controls",
"open_perms"
};
unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
#ifdef CONFIG_SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT
#define SELINUX_COMPAT_NET_VALUE 0
#else
#define SELINUX_COMPAT_NET_VALUE 1
#endif
int selinux_compat_net = SELINUX_COMPAT_NET_VALUE;
static int __init checkreqprot_setup(char *str)
{
selinux_checkreqprot = simple_strtoul(str, NULL, 0) ? 1 : 0;
return 1;
}
__setup("checkreqprot=", checkreqprot_setup);
static int __init selinux_compat_net_setup(char *str)
{
selinux_compat_net = simple_strtoul(str, NULL, 0) ? 1 : 0;
return 1;
}
__setup("selinux_compat_net=", selinux_compat_net_setup);
static DEFINE_MUTEX(sel_mutex);
/* global data for booleans */
static struct dentry *bool_dir;
static int bool_num;
static char **bool_pending_names;
static int *bool_pending_values;
/* global data for classes */
static struct dentry *class_dir;
static unsigned long last_class_ino;
/* global data for policy capabilities */
static struct dentry *policycap_dir;
extern void selnl_notify_setenforce(int val);
/* Check whether a task is allowed to use a security operation. */
static int task_has_security(struct task_struct *tsk,
u32 perms)
{
struct task_security_struct *tsec;
tsec = tsk->security;
if (!tsec)
return -EACCES;
return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
SECCLASS_SECURITY, perms, NULL);
}
enum sel_inos {
SEL_ROOT_INO = 2,
SEL_LOAD, /* load policy */
SEL_ENFORCE, /* get or set enforcing status */
SEL_CONTEXT, /* validate context */
SEL_ACCESS, /* compute access decision */
SEL_CREATE, /* compute create labeling decision */
SEL_RELABEL, /* compute relabeling decision */
SEL_USER, /* compute reachable user contexts */
SEL_POLICYVERS, /* return policy version for this kernel */
SEL_COMMIT_BOOLS, /* commit new boolean values */
SEL_MLS, /* return if MLS policy is enabled */
SEL_DISABLE, /* disable SELinux until next reboot */
SEL_MEMBER, /* compute polyinstantiation membership decision */
SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
SEL_COMPAT_NET, /* whether to use old compat network packet controls */
SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
SEL_INO_NEXT, /* The next inode number to use */
};
static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
#define SEL_INITCON_INO_OFFSET 0x01000000
#define SEL_BOOL_INO_OFFSET 0x02000000
#define SEL_CLASS_INO_OFFSET 0x04000000
#define SEL_POLICYCAP_INO_OFFSET 0x08000000
#define SEL_INO_MASK 0x00ffffff
#define TMPBUFLEN 12
static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
int new_value;
if (count >= PAGE_SIZE)
return -ENOMEM;
if (*ppos != 0) {
/* No partial writes. */
return -EINVAL;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value != selinux_enforcing) {
length = task_has_security(current, SECURITY__SETENFORCE);
if (length)
goto out;
audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
"enforcing=%d old_enforcing=%d auid=%u ses=%u",
new_value, selinux_enforcing,
audit_get_loginuid(current),
audit_get_sessionid(current));
selinux_enforcing = new_value;
if (selinux_enforcing)
avc_ss_reset(0);
selnl_notify_setenforce(selinux_enforcing);
}
length = count;
out:
free_page((unsigned long) page);
return length;
}
#else
#define sel_write_enforce NULL
#endif
static const struct file_operations sel_enforce_ops = {
.read = sel_read_enforce,
.write = sel_write_enforce,
};
static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
ino_t ino = filp->f_path.dentry->d_inode->i_ino;
int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
security_get_reject_unknown() : !security_get_allow_unknown();
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_handle_unknown_ops = {
.read = sel_read_handle_unknown,
};
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static ssize_t sel_write_disable(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
int new_value;
extern int selinux_disable(void);
if (count >= PAGE_SIZE)
return -ENOMEM;
if (*ppos != 0) {
/* No partial writes. */
return -EINVAL;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value) {
length = selinux_disable();
if (length < 0)
goto out;
audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
"selinux=0 auid=%u ses=%u",
audit_get_loginuid(current),
audit_get_sessionid(current));
}
length = count;
out:
free_page((unsigned long) page);
return length;
}
#else
#define sel_write_disable NULL
#endif
static const struct file_operations sel_disable_ops = {
.write = sel_write_disable,
};
static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_policyvers_ops = {
.read = sel_read_policyvers,
};
/* declaration for sel_write_load */
static int sel_make_bools(void);
static int sel_make_classes(void);
static int sel_make_policycap(void);
/* declaration for sel_make_class_dirs */
static int sel_make_dir(struct inode *dir, struct dentry *dentry,
unsigned long *ino);
static ssize_t sel_read_mls(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static const struct file_operations sel_mls_ops = {
.read = sel_read_mls,
};
static ssize_t sel_write_load(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
int ret;
ssize_t length;
void *data = NULL;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__LOAD_POLICY);
if (length)
goto out;
if (*ppos != 0) {
/* No partial writes. */
length = -EINVAL;
goto out;
}
if ((count > 64 * 1024 * 1024)
|| (data = vmalloc(count)) == NULL) {
length = -ENOMEM;
goto out;
}
length = -EFAULT;
if (copy_from_user(data, buf, count) != 0)
goto out;
length = security_load_policy(data, count);
if (length)
goto out;
ret = sel_make_bools();
if (ret) {
length = ret;
goto out1;
}
ret = sel_make_classes();
if (ret) {
length = ret;
goto out1;
}
ret = sel_make_policycap();
if (ret)
length = ret;
else
length = count;
out1:
printk(KERN_INFO "SELinux: policy loaded with handle_unknown=%s\n",
(security_get_reject_unknown() ? "reject" :
(security_get_allow_unknown() ? "allow" : "deny")));
audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
"policy loaded auid=%u ses=%u",
audit_get_loginuid(current),
audit_get_sessionid(current));
out:
mutex_unlock(&sel_mutex);
vfree(data);
return length;
}
static const struct file_operations sel_load_ops = {
.write = sel_write_load,
};
static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
{
char *canon;
u32 sid, len;
ssize_t length;
length = task_has_security(current, SECURITY__CHECK_CONTEXT);
if (length)
return length;
length = security_context_to_sid(buf, size, &sid);
if (length < 0)
return length;
length = security_sid_to_context(sid, &canon, &len);
if (length < 0)
return length;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
length = -ERANGE;
goto out;
}
memcpy(buf, canon, len);
length = len;
out:
kfree(canon);
return length;
}
static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
unsigned int new_value;
length = task_has_security(current, SECURITY__SETCHECKREQPROT);
if (length)
return length;
if (count >= PAGE_SIZE)
return -ENOMEM;
if (*ppos != 0) {
/* No partial writes. */
return -EINVAL;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%u", &new_value) != 1)
goto out;
selinux_checkreqprot = new_value ? 1 : 0;
length = count;
out:
free_page((unsigned long) page);
return length;
}
static const struct file_operations sel_checkreqprot_ops = {
.read = sel_read_checkreqprot,
.write = sel_write_checkreqprot,
};
static ssize_t sel_read_compat_net(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char tmpbuf[TMPBUFLEN];
ssize_t length;
length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_compat_net);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
static ssize_t sel_write_compat_net(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page;
ssize_t length;
int new_value;
length = task_has_security(current, SECURITY__LOAD_POLICY);
if (length)
return length;
if (count >= PAGE_SIZE)
return -ENOMEM;
if (*ppos != 0) {
/* No partial writes. */
return -EINVAL;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
selinux_compat_net = new_value ? 1 : 0;
length = count;
out:
free_page((unsigned long) page);
return length;
}
static const struct file_operations sel_compat_net_ops = {
.read = sel_read_compat_net,
.write = sel_write_compat_net,
};
/*
* Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
*/
static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
static ssize_t (*write_op[])(struct file *, char *, size_t) = {
[SEL_ACCESS] = sel_write_access,
[SEL_CREATE] = sel_write_create,
[SEL_RELABEL] = sel_write_relabel,
[SEL_USER] = sel_write_user,
[SEL_MEMBER] = sel_write_member,
[SEL_CONTEXT] = sel_write_context,
};
static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
{
ino_t ino = file->f_path.dentry->d_inode->i_ino;
char *data;
ssize_t rv;
if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
return -EINVAL;
data = simple_transaction_get(file, buf, size);
if (IS_ERR(data))
return PTR_ERR(data);
rv = write_op[ino](file, data, size);
if (rv > 0) {
simple_transaction_set(file, rv);
rv = size;
}
return rv;
}
static const struct file_operations transaction_ops = {
.write = selinux_transaction_write,
.read = simple_transaction_read,
.release = simple_transaction_release,
};
/*
* payload - write methods
* If the method has a response, the response should be put in buf,
* and the length returned. Otherwise return 0 or and -error.
*/
static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid;
u16 tclass;
u32 req;
struct av_decision avd;
ssize_t length;
length = task_has_security(current, SECURITY__COMPUTE_AV);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_compute_av(ssid, tsid, tclass, req, &avd);
if (length < 0)
goto out2;
length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
"%x %x %x %x %u",
avd.allowed, avd.decided,
avd.auditallow, avd.auditdeny,
avd.seqno);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon;
u32 len;
length = task_has_security(current, SECURITY__COMPUTE_CREATE);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_transition_sid(ssid, tsid, tclass, &newsid);
if (length < 0)
goto out2;
length = security_sid_to_context(newsid, &newcon, &len);
if (length < 0)
goto out2;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
length = -ERANGE;
goto out3;
}
memcpy(buf, newcon, len);
length = len;
out3:
kfree(newcon);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon;
u32 len;
length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_change_sid(ssid, tsid, tclass, &newsid);
if (length < 0)
goto out2;
length = security_sid_to_context(newsid, &newcon, &len);
if (length < 0)
goto out2;
if (len > SIMPLE_TRANSACTION_LIMIT) {
length = -ERANGE;
goto out3;
}
memcpy(buf, newcon, len);
length = len;
out3:
kfree(newcon);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
{
char *con, *user, *ptr;
u32 sid, *sids;
ssize_t length;
char *newcon;
int i, rc;
u32 len, nsids;
length = task_has_security(current, SECURITY__COMPUTE_USER);
if (length)
return length;
length = -ENOMEM;
con = kzalloc(size+1, GFP_KERNEL);
if (!con)
return length;
user = kzalloc(size+1, GFP_KERNEL);
if (!user)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s", con, user) != 2)
goto out2;
length = security_context_to_sid(con, strlen(con)+1, &sid);
if (length < 0)
goto out2;
length = security_get_user_sids(sid, user, &sids, &nsids);
if (length < 0)
goto out2;
length = sprintf(buf, "%u", nsids) + 1;
ptr = buf + length;
for (i = 0; i < nsids; i++) {
rc = security_sid_to_context(sids[i], &newcon, &len);
if (rc) {
length = rc;
goto out3;
}
if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
kfree(newcon);
length = -ERANGE;
goto out3;
}
memcpy(ptr, newcon, len);
kfree(newcon);
ptr += len;
length += len;
}
out3:
kfree(sids);
out2:
kfree(user);
out:
kfree(con);
return length;
}
static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
{
char *scon, *tcon;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon;
u32 len;
length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
if (length)
return length;
length = -ENOMEM;
scon = kzalloc(size+1, GFP_KERNEL);
if (!scon)
return length;
tcon = kzalloc(size+1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out2;
length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
if (length < 0)
goto out2;
length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
if (length < 0)
goto out2;
length = security_member_sid(ssid, tsid, tclass, &newsid);
if (length < 0)
goto out2;
length = security_sid_to_context(newsid, &newcon, &len);
if (length < 0)
goto out2;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
length = -ERANGE;
goto out3;
}
memcpy(buf, newcon, len);
length = len;
out3:
kfree(newcon);
out2:
kfree(tcon);
out:
kfree(scon);
return length;
}
static struct inode *sel_make_inode(struct super_block *sb, int mode)
{
struct inode *ret = new_inode(sb);
if (ret) {
ret->i_mode = mode;
ret->i_uid = ret->i_gid = 0;
ret->i_blocks = 0;
ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
}
return ret;
}
static ssize_t sel_read_bool(struct file *filep, char __user *buf,
size_t count, loff_t *ppos)
{
char *page = NULL;
ssize_t length;
ssize_t ret;
int cur_enforcing;
struct inode *inode = filep->f_path.dentry->d_inode;
unsigned index = inode->i_ino & SEL_INO_MASK;
const char *name = filep->f_path.dentry->d_name.name;
mutex_lock(&sel_mutex);
if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
ret = -EINVAL;
goto out;
}
if (count > PAGE_SIZE) {
ret = -EINVAL;
goto out;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page) {
ret = -ENOMEM;
goto out;
}
cur_enforcing = security_get_bool_value(index);
if (cur_enforcing < 0) {
ret = cur_enforcing;
goto out;
}
length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
bool_pending_values[index]);
ret = simple_read_from_buffer(buf, count, ppos, page, length);
out:
mutex_unlock(&sel_mutex);
if (page)
free_page((unsigned long)page);
return ret;
}
static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
size_t count, loff_t *ppos)
{
char *page = NULL;
ssize_t length;
int new_value;
struct inode *inode = filep->f_path.dentry->d_inode;
unsigned index = inode->i_ino & SEL_INO_MASK;
const char *name = filep->f_path.dentry->d_name.name;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__SETBOOL);
if (length)
goto out;
if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
length = -EINVAL;
goto out;
}
if (count >= PAGE_SIZE) {
length = -ENOMEM;
goto out;
}
if (*ppos != 0) {
/* No partial writes. */
length = -EINVAL;
goto out;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page) {
length = -ENOMEM;
goto out;
}
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value)
new_value = 1;
bool_pending_values[index] = new_value;
length = count;
out:
mutex_unlock(&sel_mutex);
if (page)
free_page((unsigned long) page);
return length;
}
static const struct file_operations sel_bool_ops = {
.read = sel_read_bool,
.write = sel_write_bool,
};
static ssize_t sel_commit_bools_write(struct file *filep,
const char __user *buf,
size_t count, loff_t *ppos)
{
char *page = NULL;
ssize_t length;
int new_value;
mutex_lock(&sel_mutex);
length = task_has_security(current, SECURITY__SETBOOL);
if (length)
goto out;
if (count >= PAGE_SIZE) {
length = -ENOMEM;
goto out;
}
if (*ppos != 0) {
/* No partial writes. */
goto out;
}
page = (char *)get_zeroed_page(GFP_KERNEL);
if (!page) {
length = -ENOMEM;
goto out;
}
length = -EFAULT;
if (copy_from_user(page, buf, count))
goto out;
length = -EINVAL;
if (sscanf(page, "%d", &new_value) != 1)
goto out;
if (new_value && bool_pending_values)
security_set_bools(bool_num, bool_pending_values);
length = count;
out: