KEYS: Move the unreferenced key reaper to the keys garbage collector file
Move the unreferenced key reaper function to the keys garbage collector file
as that's a more appropriate place with the dead key link reaper.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/keys/gc.c b/security/keys/gc.c
index 89df6b5..b23db3f 100644
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -10,6 +10,8 @@
*/
#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/security.h>
#include <keys/keyring-type.h>
#include "internal.h"
@@ -19,12 +21,18 @@
unsigned key_gc_delay = 5 * 60;
/*
- * Reaper
+ * Reaper for unused keys.
+ */
+static void key_gc_unused_keys(struct work_struct *work);
+DECLARE_WORK(key_gc_unused_work, key_gc_unused_keys);
+
+/*
+ * Reaper for links from keyrings to dead keys.
*/
static void key_gc_timer_func(unsigned long);
-static void key_garbage_collector(struct work_struct *);
+static void key_gc_dead_links(struct work_struct *);
static DEFINE_TIMER(key_gc_timer, key_gc_timer_func, 0, 0);
-static DECLARE_WORK(key_gc_work, key_garbage_collector);
+static DECLARE_WORK(key_gc_work, key_gc_dead_links);
static key_serial_t key_gc_cursor; /* the last key the gc considered */
static bool key_gc_again;
static unsigned long key_gc_executing;
@@ -108,10 +116,12 @@
}
/*
- * Garbage collector for keys. This involves scanning the keyrings for dead,
- * expired and revoked keys that have overstayed their welcome
+ * Garbage collector for links to dead keys.
+ *
+ * This involves scanning the keyrings for dead, expired and revoked keys that
+ * have overstayed their welcome
*/
-static void key_garbage_collector(struct work_struct *work)
+static void key_gc_dead_links(struct work_struct *work)
{
struct rb_node *rb;
key_serial_t cursor;
@@ -220,3 +230,68 @@
}
kleave(" [end]");
}
+
+/*
+ * Garbage collector for unused keys.
+ *
+ * This is done in process context so that we don't have to disable interrupts
+ * all over the place. key_put() schedules this rather than trying to do the
+ * cleanup itself, which means key_put() doesn't have to sleep.
+ */
+static void key_gc_unused_keys(struct work_struct *work)
+{
+ struct rb_node *_n;
+ struct key *key;
+
+go_again:
+ /* look for a dead key in the tree */
+ spin_lock(&key_serial_lock);
+
+ for (_n = rb_first(&key_serial_tree); _n; _n = rb_next(_n)) {
+ key = rb_entry(_n, struct key, serial_node);
+
+ if (atomic_read(&key->usage) == 0)
+ goto found_dead_key;
+ }
+
+ spin_unlock(&key_serial_lock);
+ return;
+
+found_dead_key:
+ /* we found a dead key - once we've removed it from the tree, we can
+ * drop the lock */
+ rb_erase(&key->serial_node, &key_serial_tree);
+ spin_unlock(&key_serial_lock);
+
+ key_check(key);
+
+ security_key_free(key);
+
+ /* deal with the user's key tracking and quota */
+ if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ spin_lock(&key->user->lock);
+ key->user->qnkeys--;
+ key->user->qnbytes -= key->quotalen;
+ spin_unlock(&key->user->lock);
+ }
+
+ atomic_dec(&key->user->nkeys);
+ if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
+ atomic_dec(&key->user->nikeys);
+
+ key_user_put(key->user);
+
+ /* now throw away the key memory */
+ if (key->type->destroy)
+ key->type->destroy(key);
+
+ kfree(key->description);
+
+#ifdef KEY_DEBUGGING
+ key->magic = KEY_DEBUG_MAGIC_X;
+#endif
+ kmem_cache_free(key_jar, key);
+
+ /* there may, of course, be more than one key to destroy */
+ goto go_again;
+}