KEYS: Have the garbage collector set its timer for live expired keys

The key garbage collector sets a timer to start a new collection cycle at the
point the earliest key to expire should be considered garbage.  However, it
currently only does this if the key it is considering hasn't yet expired.

If the key being considering has expired, but hasn't yet reached the collection
time then it is ignored, and won't be collected until some other key provokes a
round of collection.

Make the garbage collector set the timer for the earliest key that hasn't yet
passed its collection time, rather than the earliest key that hasn't yet
expired.

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 485fc6233c38e16336bc9886c0dbfceb2fa63cdd..4770be375ffece3d506ea86b769aee3bf8607595 100644 (file)
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -169,9 +169,9 @@ static void key_garbage_collector(struct work_struct *work)
 
        /* trawl through the keys looking for keyrings */
        for (;;) {
-               if (key->expiry > now && key->expiry < new_timer) {
+               if (key->expiry > limit && key->expiry < new_timer) {
                        kdebug("will expire %x in %ld",
-                              key_serial(key), key->expiry - now);
+                              key_serial(key), key->expiry - limit);
                        new_timer = key->expiry;
                }