spin_unlock(&sysctl_lock);
wait_for_completion(&wait);
spin_lock(&sysctl_lock);
+ } else {
+ /* anything non-NULL; we'll never dereference it */
+ p->unregistering = ERR_PTR(-EINVAL);
}
/*
* do not remove from the list until nobody holds it; walking the
list_del_init(&p->ctl_entry);
}
+void sysctl_head_get(struct ctl_table_header *head)
+{
+ spin_lock(&sysctl_lock);
+ head->count++;
+ spin_unlock(&sysctl_lock);
+}
+
+void sysctl_head_put(struct ctl_table_header *head)
+{
+ spin_lock(&sysctl_lock);
+ if (!--head->count)
+ kfree(head);
+ spin_unlock(&sysctl_lock);
+}
+
+struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
+{
+ if (!head)
+ BUG();
+ spin_lock(&sysctl_lock);
+ if (!use_table(head))
+ head = ERR_PTR(-ENOENT);
+ spin_unlock(&sysctl_lock);
+ return head;
+}
+
void sysctl_head_finish(struct ctl_table_header *head)
{
if (!head)
int op = 0, rc;
if (oldval)
- op |= 004;
+ op |= MAY_READ;
if (newval)
- op |= 002;
+ op |= MAY_WRITE;
if (sysctl_perm(root, table, op))
return -EPERM;
if (n == table->ctl_name) {
int error;
if (table->child) {
- if (sysctl_perm(root, table, 001))
+ if (sysctl_perm(root, table, MAY_EXEC))
return -EPERM;
name++;
nlen--;
mode >>= 6;
else if (in_egroup_p(0))
mode >>= 3;
- if ((mode & op & 0007) == op)
+ if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
return 0;
return -EACCES;
}
int error;
int mode;
- error = security_sysctl(table, op);
+ error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
if (error)
return error;
core_initcall(sysctl_init);
+static struct ctl_table *is_branch_in(struct ctl_table *branch,
+ struct ctl_table *table)
+{
+ struct ctl_table *p;
+ const char *s = branch->procname;
+
+ /* branch should have named subdirectory as its first element */
+ if (!s || !branch->child)
+ return NULL;
+
+ /* ... and nothing else */
+ if (branch[1].procname || branch[1].ctl_name)
+ return NULL;
+
+ /* table should contain subdirectory with the same name */
+ for (p = table; p->procname || p->ctl_name; p++) {
+ if (!p->child)
+ continue;
+ if (p->procname && strcmp(p->procname, s) == 0)
+ return p;
+ }
+ return NULL;
+}
+
+/* see if attaching q to p would be an improvement */
+static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
+{
+ struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
+ struct ctl_table *next;
+ int is_better = 0;
+ int not_in_parent = !p->attached_by;
+
+ while ((next = is_branch_in(by, to)) != NULL) {
+ if (by == q->attached_by)
+ is_better = 1;
+ if (to == p->attached_by)
+ not_in_parent = 1;
+ by = by->child;
+ to = next->child;
+ }
+
+ if (is_better && not_in_parent) {
+ q->attached_by = by;
+ q->attached_to = to;
+ q->parent = p;
+ }
+}
+
/**
* __register_sysctl_paths - register a sysctl hierarchy
* @root: List of sysctl headers to register on
struct ctl_table_header *header;
struct ctl_table *new, **prevp;
unsigned int n, npath;
+ struct ctl_table_set *set;
/* Count the path components */
for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
header->unregistering = NULL;
header->root = root;
sysctl_set_parent(NULL, header->ctl_table);
+ header->count = 1;
#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
if (sysctl_check_table(namespaces, header->ctl_table)) {
kfree(header);
#endif
spin_lock(&sysctl_lock);
header->set = lookup_header_set(root, namespaces);
+ header->attached_by = header->ctl_table;
+ header->attached_to = root_table;
+ header->parent = &root_table_header;
+ for (set = header->set; set; set = set->parent) {
+ struct ctl_table_header *p;
+ list_for_each_entry(p, &set->list, ctl_entry) {
+ if (p->unregistering)
+ continue;
+ try_attach(p, header);
+ }
+ }
+ header->parent->count++;
list_add_tail(&header->ctl_entry, &header->set->list);
spin_unlock(&sysctl_lock);
spin_lock(&sysctl_lock);
start_unregistering(header);
+ if (!--header->parent->count) {
+ WARN_ON(1);
+ kfree(header->parent);
+ }
+ if (!--header->count)
+ kfree(header);
+ spin_unlock(&sysctl_lock);
+}
+
+int sysctl_is_seen(struct ctl_table_header *p)
+{
+ struct ctl_table_set *set = p->set;
+ int res;
+ spin_lock(&sysctl_lock);
+ if (p->unregistering)
+ res = 0;
+ else if (!set->is_seen)
+ res = 1;
+ else
+ res = set->is_seen(set);
spin_unlock(&sysctl_lock);
- kfree(header);
+ return res;
}
void setup_sysctl_set(struct ctl_table_set *p,
{
}
+void sysctl_head_put(struct ctl_table_header *head)
+{
+}
+
#endif /* CONFIG_SYSCTL */
/*