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0f2a55d5bb
Update comments for scripts/kernel-doc and fix some of errors reported by scripts/checkpatch.pl . Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
726 lines
20 KiB
C
726 lines
20 KiB
C
/*
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* security/tomoyo/gc.c
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*
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* Copyright (C) 2005-2011 NTT DATA CORPORATION
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*/
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#include "common.h"
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#include <linux/kthread.h>
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#include <linux/slab.h>
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/* The list for "struct tomoyo_io_buffer". */
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static LIST_HEAD(tomoyo_io_buffer_list);
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/* Lock for protecting tomoyo_io_buffer_list. */
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static DEFINE_SPINLOCK(tomoyo_io_buffer_list_lock);
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/* Size of an element. */
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static const u8 tomoyo_element_size[TOMOYO_MAX_POLICY] = {
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[TOMOYO_ID_GROUP] = sizeof(struct tomoyo_group),
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[TOMOYO_ID_PATH_GROUP] = sizeof(struct tomoyo_path_group),
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[TOMOYO_ID_NUMBER_GROUP] = sizeof(struct tomoyo_number_group),
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[TOMOYO_ID_AGGREGATOR] = sizeof(struct tomoyo_aggregator),
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[TOMOYO_ID_TRANSITION_CONTROL] =
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sizeof(struct tomoyo_transition_control),
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[TOMOYO_ID_MANAGER] = sizeof(struct tomoyo_manager),
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/* [TOMOYO_ID_CONDITION] = "struct tomoyo_condition"->size, */
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/* [TOMOYO_ID_NAME] = "struct tomoyo_name"->size, */
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/* [TOMOYO_ID_ACL] =
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tomoyo_acl_size["struct tomoyo_acl_info"->type], */
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[TOMOYO_ID_DOMAIN] = sizeof(struct tomoyo_domain_info),
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};
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/* Size of a domain ACL element. */
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static const u8 tomoyo_acl_size[] = {
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[TOMOYO_TYPE_PATH_ACL] = sizeof(struct tomoyo_path_acl),
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[TOMOYO_TYPE_PATH2_ACL] = sizeof(struct tomoyo_path2_acl),
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[TOMOYO_TYPE_PATH_NUMBER_ACL] = sizeof(struct tomoyo_path_number_acl),
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[TOMOYO_TYPE_MKDEV_ACL] = sizeof(struct tomoyo_mkdev_acl),
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[TOMOYO_TYPE_MOUNT_ACL] = sizeof(struct tomoyo_mount_acl),
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};
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/**
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* tomoyo_struct_used_by_io_buffer - Check whether the list element is used by /sys/kernel/security/tomoyo/ users or not.
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns true if @element is used by /sys/kernel/security/tomoyo/ users,
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* false otherwise.
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*/
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static bool tomoyo_struct_used_by_io_buffer(const struct list_head *element)
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{
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struct tomoyo_io_buffer *head;
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bool in_use = false;
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spin_lock(&tomoyo_io_buffer_list_lock);
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list_for_each_entry(head, &tomoyo_io_buffer_list, list) {
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head->users++;
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spin_unlock(&tomoyo_io_buffer_list_lock);
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if (mutex_lock_interruptible(&head->io_sem)) {
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in_use = true;
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goto out;
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}
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if (head->r.domain == element || head->r.group == element ||
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head->r.acl == element || &head->w.domain->list == element)
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in_use = true;
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mutex_unlock(&head->io_sem);
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out:
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spin_lock(&tomoyo_io_buffer_list_lock);
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head->users--;
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if (in_use)
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break;
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}
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spin_unlock(&tomoyo_io_buffer_list_lock);
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return in_use;
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}
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/**
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* tomoyo_name_used_by_io_buffer - Check whether the string is used by /sys/kernel/security/tomoyo/ users or not.
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*
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* @string: String to check.
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* @size: Memory allocated for @string .
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*
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* Returns true if @string is used by /sys/kernel/security/tomoyo/ users,
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* false otherwise.
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*/
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static bool tomoyo_name_used_by_io_buffer(const char *string,
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const size_t size)
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{
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struct tomoyo_io_buffer *head;
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bool in_use = false;
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spin_lock(&tomoyo_io_buffer_list_lock);
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list_for_each_entry(head, &tomoyo_io_buffer_list, list) {
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int i;
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head->users++;
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spin_unlock(&tomoyo_io_buffer_list_lock);
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if (mutex_lock_interruptible(&head->io_sem)) {
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in_use = true;
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goto out;
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}
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for (i = 0; i < TOMOYO_MAX_IO_READ_QUEUE; i++) {
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const char *w = head->r.w[i];
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if (w < string || w > string + size)
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continue;
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in_use = true;
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break;
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}
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mutex_unlock(&head->io_sem);
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out:
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spin_lock(&tomoyo_io_buffer_list_lock);
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head->users--;
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if (in_use)
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break;
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}
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spin_unlock(&tomoyo_io_buffer_list_lock);
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return in_use;
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}
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/* Structure for garbage collection. */
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struct tomoyo_gc {
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struct list_head list;
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enum tomoyo_policy_id type;
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size_t size;
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struct list_head *element;
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};
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/* List of entries to be deleted. */
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static LIST_HEAD(tomoyo_gc_list);
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/* Length of tomoyo_gc_list. */
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static int tomoyo_gc_list_len;
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/**
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* tomoyo_add_to_gc - Add an entry to to be deleted list.
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*
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* @type: One of values in "enum tomoyo_policy_id".
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* @element: Pointer to "struct list_head".
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*
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* Returns true on success, false otherwise.
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*
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* Caller holds tomoyo_policy_lock mutex.
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*
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* Adding an entry needs kmalloc(). Thus, if we try to add thousands of
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* entries at once, it will take too long time. Thus, do not add more than 128
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* entries per a scan. But to be able to handle worst case where all entries
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* are in-use, we accept one more entry per a scan.
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*
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* If we use singly linked list using "struct list_head"->prev (which is
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* LIST_POISON2), we can avoid kmalloc().
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*/
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static bool tomoyo_add_to_gc(const int type, struct list_head *element)
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{
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struct tomoyo_gc *entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
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if (!entry)
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return false;
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entry->type = type;
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if (type == TOMOYO_ID_ACL)
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entry->size = tomoyo_acl_size[
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container_of(element,
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typeof(struct tomoyo_acl_info),
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list)->type];
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else if (type == TOMOYO_ID_NAME)
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entry->size = strlen(container_of(element,
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typeof(struct tomoyo_name),
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head.list)->entry.name) + 1;
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else if (type == TOMOYO_ID_CONDITION)
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entry->size =
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container_of(element, typeof(struct tomoyo_condition),
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head.list)->size;
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else
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entry->size = tomoyo_element_size[type];
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entry->element = element;
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list_add(&entry->list, &tomoyo_gc_list);
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list_del_rcu(element);
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return tomoyo_gc_list_len++ < 128;
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}
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/**
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* tomoyo_element_linked_by_gc - Validate next element of an entry.
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*
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* @element: Pointer to an element.
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* @size: Size of @element in byte.
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*
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* Returns true if @element is linked by other elements in the garbage
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* collector's queue, false otherwise.
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*/
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static bool tomoyo_element_linked_by_gc(const u8 *element, const size_t size)
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{
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struct tomoyo_gc *p;
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list_for_each_entry(p, &tomoyo_gc_list, list) {
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const u8 *ptr = (const u8 *) p->element->next;
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if (ptr < element || element + size < ptr)
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continue;
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return true;
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}
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return false;
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}
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/**
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* tomoyo_del_transition_control - Delete members in "struct tomoyo_transition_control".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_transition_control(struct list_head *element)
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{
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struct tomoyo_transition_control *ptr =
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container_of(element, typeof(*ptr), head.list);
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tomoyo_put_name(ptr->domainname);
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tomoyo_put_name(ptr->program);
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}
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/**
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* tomoyo_del_aggregator - Delete members in "struct tomoyo_aggregator".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_aggregator(struct list_head *element)
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{
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struct tomoyo_aggregator *ptr =
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container_of(element, typeof(*ptr), head.list);
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tomoyo_put_name(ptr->original_name);
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tomoyo_put_name(ptr->aggregated_name);
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}
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/**
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* tomoyo_del_manager - Delete members in "struct tomoyo_manager".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_manager(struct list_head *element)
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{
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struct tomoyo_manager *ptr =
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container_of(element, typeof(*ptr), head.list);
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tomoyo_put_name(ptr->manager);
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}
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/**
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* tomoyo_del_acl - Delete members in "struct tomoyo_acl_info".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_acl(struct list_head *element)
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{
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struct tomoyo_acl_info *acl =
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container_of(element, typeof(*acl), list);
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tomoyo_put_condition(acl->cond);
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switch (acl->type) {
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case TOMOYO_TYPE_PATH_ACL:
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{
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struct tomoyo_path_acl *entry
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= container_of(acl, typeof(*entry), head);
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tomoyo_put_name_union(&entry->name);
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}
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break;
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case TOMOYO_TYPE_PATH2_ACL:
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{
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struct tomoyo_path2_acl *entry
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= container_of(acl, typeof(*entry), head);
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tomoyo_put_name_union(&entry->name1);
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tomoyo_put_name_union(&entry->name2);
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}
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break;
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case TOMOYO_TYPE_PATH_NUMBER_ACL:
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{
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struct tomoyo_path_number_acl *entry
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= container_of(acl, typeof(*entry), head);
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tomoyo_put_name_union(&entry->name);
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tomoyo_put_number_union(&entry->number);
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}
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break;
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case TOMOYO_TYPE_MKDEV_ACL:
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{
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struct tomoyo_mkdev_acl *entry
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= container_of(acl, typeof(*entry), head);
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tomoyo_put_name_union(&entry->name);
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tomoyo_put_number_union(&entry->mode);
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tomoyo_put_number_union(&entry->major);
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tomoyo_put_number_union(&entry->minor);
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}
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break;
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case TOMOYO_TYPE_MOUNT_ACL:
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{
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struct tomoyo_mount_acl *entry
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= container_of(acl, typeof(*entry), head);
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tomoyo_put_name_union(&entry->dev_name);
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tomoyo_put_name_union(&entry->dir_name);
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tomoyo_put_name_union(&entry->fs_type);
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tomoyo_put_number_union(&entry->flags);
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}
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break;
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}
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}
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/**
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* tomoyo_del_domain - Delete members in "struct tomoyo_domain_info".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns true if deleted, false otherwise.
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*/
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static bool tomoyo_del_domain(struct list_head *element)
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{
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struct tomoyo_domain_info *domain =
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container_of(element, typeof(*domain), list);
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struct tomoyo_acl_info *acl;
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struct tomoyo_acl_info *tmp;
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/*
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* Since we don't protect whole execve() operation using SRCU,
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* we need to recheck domain->users at this point.
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*
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* (1) Reader starts SRCU section upon execve().
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* (2) Reader traverses tomoyo_domain_list and finds this domain.
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* (3) Writer marks this domain as deleted.
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* (4) Garbage collector removes this domain from tomoyo_domain_list
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* because this domain is marked as deleted and used by nobody.
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* (5) Reader saves reference to this domain into
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* "struct linux_binprm"->cred->security .
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* (6) Reader finishes SRCU section, although execve() operation has
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* not finished yet.
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* (7) Garbage collector waits for SRCU synchronization.
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* (8) Garbage collector kfree() this domain because this domain is
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* used by nobody.
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* (9) Reader finishes execve() operation and restores this domain from
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* "struct linux_binprm"->cred->security.
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*
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* By updating domain->users at (5), we can solve this race problem
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* by rechecking domain->users at (8).
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*/
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if (atomic_read(&domain->users))
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return false;
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list_for_each_entry_safe(acl, tmp, &domain->acl_info_list, list) {
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tomoyo_del_acl(&acl->list);
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tomoyo_memory_free(acl);
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}
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tomoyo_put_name(domain->domainname);
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return true;
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}
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/**
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* tomoyo_del_condition - Delete members in "struct tomoyo_condition".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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void tomoyo_del_condition(struct list_head *element)
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{
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struct tomoyo_condition *cond = container_of(element, typeof(*cond),
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head.list);
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const u16 condc = cond->condc;
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const u16 numbers_count = cond->numbers_count;
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const u16 names_count = cond->names_count;
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const u16 argc = cond->argc;
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const u16 envc = cond->envc;
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unsigned int i;
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const struct tomoyo_condition_element *condp
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= (const struct tomoyo_condition_element *) (cond + 1);
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struct tomoyo_number_union *numbers_p
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= (struct tomoyo_number_union *) (condp + condc);
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struct tomoyo_name_union *names_p
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= (struct tomoyo_name_union *) (numbers_p + numbers_count);
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const struct tomoyo_argv *argv
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= (const struct tomoyo_argv *) (names_p + names_count);
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const struct tomoyo_envp *envp
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= (const struct tomoyo_envp *) (argv + argc);
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for (i = 0; i < numbers_count; i++)
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tomoyo_put_number_union(numbers_p++);
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for (i = 0; i < names_count; i++)
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tomoyo_put_name_union(names_p++);
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for (i = 0; i < argc; argv++, i++)
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tomoyo_put_name(argv->value);
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for (i = 0; i < envc; envp++, i++) {
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tomoyo_put_name(envp->name);
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tomoyo_put_name(envp->value);
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}
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}
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/**
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* tomoyo_del_name - Delete members in "struct tomoyo_name".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_name(struct list_head *element)
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{
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const struct tomoyo_name *ptr =
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container_of(element, typeof(*ptr), head.list);
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}
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/**
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* tomoyo_del_path_group - Delete members in "struct tomoyo_path_group".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_path_group(struct list_head *element)
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{
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struct tomoyo_path_group *member =
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container_of(element, typeof(*member), head.list);
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tomoyo_put_name(member->member_name);
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}
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/**
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* tomoyo_del_group - Delete "struct tomoyo_group".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_group(struct list_head *element)
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{
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struct tomoyo_group *group =
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container_of(element, typeof(*group), head.list);
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tomoyo_put_name(group->group_name);
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}
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/**
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* tomoyo_del_number_group - Delete members in "struct tomoyo_number_group".
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*
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* @element: Pointer to "struct list_head".
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*
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* Returns nothing.
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*/
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static void tomoyo_del_number_group(struct list_head *element)
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{
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struct tomoyo_number_group *member =
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container_of(element, typeof(*member), head.list);
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}
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/**
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* tomoyo_collect_member - Delete elements with "struct tomoyo_acl_head".
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*
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* @id: One of values in "enum tomoyo_policy_id".
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* @member_list: Pointer to "struct list_head".
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*
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* Returns true if some elements are deleted, false otherwise.
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*/
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static bool tomoyo_collect_member(const enum tomoyo_policy_id id,
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struct list_head *member_list)
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{
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struct tomoyo_acl_head *member;
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list_for_each_entry(member, member_list, list) {
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if (!member->is_deleted)
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continue;
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if (!tomoyo_add_to_gc(id, &member->list))
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return false;
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}
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return true;
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}
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/**
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* tomoyo_collect_acl - Delete elements in "struct tomoyo_domain_info".
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*
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* @list: Pointer to "struct list_head".
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*
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* Returns true if some elements are deleted, false otherwise.
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*/
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static bool tomoyo_collect_acl(struct list_head *list)
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{
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struct tomoyo_acl_info *acl;
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list_for_each_entry(acl, list, list) {
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if (!acl->is_deleted)
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continue;
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if (!tomoyo_add_to_gc(TOMOYO_ID_ACL, &acl->list))
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return false;
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}
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return true;
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}
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/**
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* tomoyo_collect_entry - Scan lists for deleted elements.
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*
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* Returns nothing.
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*/
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static void tomoyo_collect_entry(void)
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{
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int i;
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enum tomoyo_policy_id id;
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struct tomoyo_policy_namespace *ns;
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int idx;
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if (mutex_lock_interruptible(&tomoyo_policy_lock))
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return;
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|
idx = tomoyo_read_lock();
|
|
{
|
|
struct tomoyo_domain_info *domain;
|
|
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
|
|
if (!tomoyo_collect_acl(&domain->acl_info_list))
|
|
goto unlock;
|
|
if (!domain->is_deleted || atomic_read(&domain->users))
|
|
continue;
|
|
/*
|
|
* Nobody is referring this domain. But somebody may
|
|
* refer this domain after successful execve().
|
|
* We recheck domain->users after SRCU synchronization.
|
|
*/
|
|
if (!tomoyo_add_to_gc(TOMOYO_ID_DOMAIN, &domain->list))
|
|
goto unlock;
|
|
}
|
|
}
|
|
list_for_each_entry_rcu(ns, &tomoyo_namespace_list, namespace_list) {
|
|
for (id = 0; id < TOMOYO_MAX_POLICY; id++)
|
|
if (!tomoyo_collect_member(id, &ns->policy_list[id]))
|
|
goto unlock;
|
|
for (i = 0; i < TOMOYO_MAX_ACL_GROUPS; i++)
|
|
if (!tomoyo_collect_acl(&ns->acl_group[i]))
|
|
goto unlock;
|
|
for (i = 0; i < TOMOYO_MAX_GROUP; i++) {
|
|
struct list_head *list = &ns->group_list[i];
|
|
struct tomoyo_group *group;
|
|
switch (i) {
|
|
case 0:
|
|
id = TOMOYO_ID_PATH_GROUP;
|
|
break;
|
|
default:
|
|
id = TOMOYO_ID_NUMBER_GROUP;
|
|
break;
|
|
}
|
|
list_for_each_entry(group, list, head.list) {
|
|
if (!tomoyo_collect_member
|
|
(id, &group->member_list))
|
|
goto unlock;
|
|
if (!list_empty(&group->member_list) ||
|
|
atomic_read(&group->head.users))
|
|
continue;
|
|
if (!tomoyo_add_to_gc(TOMOYO_ID_GROUP,
|
|
&group->head.list))
|
|
goto unlock;
|
|
}
|
|
}
|
|
}
|
|
id = TOMOYO_ID_CONDITION;
|
|
for (i = 0; i < TOMOYO_MAX_HASH + 1; i++) {
|
|
struct list_head *list = !i ?
|
|
&tomoyo_condition_list : &tomoyo_name_list[i - 1];
|
|
struct tomoyo_shared_acl_head *ptr;
|
|
list_for_each_entry(ptr, list, list) {
|
|
if (atomic_read(&ptr->users))
|
|
continue;
|
|
if (!tomoyo_add_to_gc(id, &ptr->list))
|
|
goto unlock;
|
|
}
|
|
id = TOMOYO_ID_NAME;
|
|
}
|
|
unlock:
|
|
tomoyo_read_unlock(idx);
|
|
mutex_unlock(&tomoyo_policy_lock);
|
|
}
|
|
|
|
/**
|
|
* tomoyo_kfree_entry - Delete entries in tomoyo_gc_list.
|
|
*
|
|
* Returns true if some entries were kfree()d, false otherwise.
|
|
*/
|
|
static bool tomoyo_kfree_entry(void)
|
|
{
|
|
struct tomoyo_gc *p;
|
|
struct tomoyo_gc *tmp;
|
|
bool result = false;
|
|
|
|
list_for_each_entry_safe(p, tmp, &tomoyo_gc_list, list) {
|
|
struct list_head *element = p->element;
|
|
|
|
/*
|
|
* list_del_rcu() in tomoyo_add_to_gc() guarantees that the
|
|
* list element became no longer reachable from the list which
|
|
* the element was originally on (e.g. tomoyo_domain_list).
|
|
* Also, synchronize_srcu() in tomoyo_gc_thread() guarantees
|
|
* that the list element became no longer referenced by syscall
|
|
* users.
|
|
*
|
|
* However, there are three users which may still be using the
|
|
* list element. We need to defer until all of these users
|
|
* forget the list element.
|
|
*
|
|
* Firstly, defer until "struct tomoyo_io_buffer"->r.{domain,
|
|
* group,acl} and "struct tomoyo_io_buffer"->w.domain forget
|
|
* the list element.
|
|
*/
|
|
if (tomoyo_struct_used_by_io_buffer(element))
|
|
continue;
|
|
/*
|
|
* Secondly, defer until all other elements in the
|
|
* tomoyo_gc_list list forget the list element.
|
|
*/
|
|
if (tomoyo_element_linked_by_gc((const u8 *) element, p->size))
|
|
continue;
|
|
switch (p->type) {
|
|
case TOMOYO_ID_TRANSITION_CONTROL:
|
|
tomoyo_del_transition_control(element);
|
|
break;
|
|
case TOMOYO_ID_AGGREGATOR:
|
|
tomoyo_del_aggregator(element);
|
|
break;
|
|
case TOMOYO_ID_MANAGER:
|
|
tomoyo_del_manager(element);
|
|
break;
|
|
case TOMOYO_ID_CONDITION:
|
|
tomoyo_del_condition(element);
|
|
break;
|
|
case TOMOYO_ID_NAME:
|
|
/*
|
|
* Thirdly, defer until all "struct tomoyo_io_buffer"
|
|
* ->r.w[] forget the list element.
|
|
*/
|
|
if (tomoyo_name_used_by_io_buffer(
|
|
container_of(element, typeof(struct tomoyo_name),
|
|
head.list)->entry.name, p->size))
|
|
continue;
|
|
tomoyo_del_name(element);
|
|
break;
|
|
case TOMOYO_ID_ACL:
|
|
tomoyo_del_acl(element);
|
|
break;
|
|
case TOMOYO_ID_DOMAIN:
|
|
if (!tomoyo_del_domain(element))
|
|
continue;
|
|
break;
|
|
case TOMOYO_ID_PATH_GROUP:
|
|
tomoyo_del_path_group(element);
|
|
break;
|
|
case TOMOYO_ID_GROUP:
|
|
tomoyo_del_group(element);
|
|
break;
|
|
case TOMOYO_ID_NUMBER_GROUP:
|
|
tomoyo_del_number_group(element);
|
|
break;
|
|
case TOMOYO_MAX_POLICY:
|
|
break;
|
|
}
|
|
tomoyo_memory_free(element);
|
|
list_del(&p->list);
|
|
kfree(p);
|
|
tomoyo_gc_list_len--;
|
|
result = true;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* tomoyo_gc_thread - Garbage collector thread function.
|
|
*
|
|
* @unused: Unused.
|
|
*
|
|
* In case OOM-killer choose this thread for termination, we create this thread
|
|
* as a short live thread whenever /sys/kernel/security/tomoyo/ interface was
|
|
* close()d.
|
|
*
|
|
* Returns 0.
|
|
*/
|
|
static int tomoyo_gc_thread(void *unused)
|
|
{
|
|
/* Garbage collector thread is exclusive. */
|
|
static DEFINE_MUTEX(tomoyo_gc_mutex);
|
|
if (!mutex_trylock(&tomoyo_gc_mutex))
|
|
goto out;
|
|
daemonize("GC for TOMOYO");
|
|
do {
|
|
tomoyo_collect_entry();
|
|
if (list_empty(&tomoyo_gc_list))
|
|
break;
|
|
synchronize_srcu(&tomoyo_ss);
|
|
} while (tomoyo_kfree_entry());
|
|
{
|
|
struct tomoyo_io_buffer *head;
|
|
struct tomoyo_io_buffer *tmp;
|
|
|
|
spin_lock(&tomoyo_io_buffer_list_lock);
|
|
list_for_each_entry_safe(head, tmp, &tomoyo_io_buffer_list,
|
|
list) {
|
|
if (head->users)
|
|
continue;
|
|
list_del(&head->list);
|
|
kfree(head->read_buf);
|
|
kfree(head->write_buf);
|
|
kfree(head);
|
|
}
|
|
spin_unlock(&tomoyo_io_buffer_list_lock);
|
|
}
|
|
mutex_unlock(&tomoyo_gc_mutex);
|
|
out:
|
|
/* This acts as do_exit(0). */
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* tomoyo_notify_gc - Register/unregister /sys/kernel/security/tomoyo/ users.
|
|
*
|
|
* @head: Pointer to "struct tomoyo_io_buffer".
|
|
* @is_register: True if register, false if unregister.
|
|
*
|
|
* Returns nothing.
|
|
*/
|
|
void tomoyo_notify_gc(struct tomoyo_io_buffer *head, const bool is_register)
|
|
{
|
|
bool is_write = false;
|
|
|
|
spin_lock(&tomoyo_io_buffer_list_lock);
|
|
if (is_register) {
|
|
head->users = 1;
|
|
list_add(&head->list, &tomoyo_io_buffer_list);
|
|
} else {
|
|
is_write = head->write_buf != NULL;
|
|
if (!--head->users) {
|
|
list_del(&head->list);
|
|
kfree(head->read_buf);
|
|
kfree(head->write_buf);
|
|
kfree(head);
|
|
}
|
|
}
|
|
spin_unlock(&tomoyo_io_buffer_list_lock);
|
|
if (is_write) {
|
|
struct task_struct *task = kthread_create(tomoyo_gc_thread,
|
|
NULL,
|
|
"GC for TOMOYO");
|
|
if (!IS_ERR(task))
|
|
wake_up_process(task);
|
|
}
|
|
}
|