/*
* selinux_kernel_status_page
*
* It returns a reference to selinux_status_page. If the status page is
* not allocated yet, it also tries to allocate it at the first time.
*/
struct page *selinux_kernel_status_page(void)
{
struct selinux_kernel_status *status;
struct page *result = NULL;
mutex_lock(&selinux_status_lock);
if (!selinux_status_page) {
selinux_status_page = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (selinux_status_page) {
status = page_address(selinux_status_page);
status->version = SELINUX_KERNEL_STATUS_VERSION;
status->sequence = 0;
status->enforcing = selinux_enforcing;
/*
* NOTE: the next policyload event shall set
* a positive value on the status->policyload,
* although it may not be 1, but never zero.
* So, application can know it was updated.
*/
status->policyload = 0;
status->deny_unknown = !security_get_allow_unknown();
}
}
result = selinux_status_page;
mutex_unlock(&selinux_status_lock);
return result;
}
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);
}
/*
* selinux_status_update_policyload
*
* It updates status of the times of policy reloaded, and current
* setting of deny_unknown.
*/
void selinux_status_update_policyload(int seqno)
{
struct selinux_kernel_status *status;
mutex_lock(&selinux_status_lock);
if (selinux_status_page) {
status = page_address(selinux_status_page);
status->sequence++;
smp_wmb();
status->policyload = seqno;
status->deny_unknown = !security_get_allow_unknown();
smp_wmb();
status->sequence++;
}
mutex_unlock(&selinux_status_lock);
}
struct page *selinux_kernel_status_page(void)
{
struct selinux_kernel_status *status;
struct page *result = NULL;
mutex_lock(&selinux_status_lock);
if (!selinux_status_page) {
selinux_status_page = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (selinux_status_page) {
status = page_address(selinux_status_page);
status->version = SELINUX_KERNEL_STATUS_VERSION;
status->sequence = 0;
status->enforcing = selinux_enforcing;
status->policyload = 0;
status->deny_unknown = !security_get_allow_unknown();
}
}
result = selinux_status_page;
mutex_unlock(&selinux_status_lock);
return result;
}
