diff options
author | David Howells <dhowells@redhat.com> | 2012-01-17 20:39:40 +0000 |
---|---|---|
committer | James Morris <jmorris@namei.org> | 2012-01-18 10:41:27 +1100 |
commit | efde8b6e16f11e7d1681c68d86c7fd51053cada7 (patch) | |
tree | 4fb5e80428c4f36c5da35ff3319cd71c1771451c /security/keys/gc.c | |
parent | 25add8cf99c9ec8b8dc0acd8b9241e963fc0d29c (diff) |
KEYS: Add missing smp_rmb() primitives to the keyring search code
Add missing smp_rmb() primitives to the keyring search code.
When keyring payloads are appended to without replacement (thus using up spare
slots in the key pointer array), an smp_wmb() is issued between the pointer
assignment and the increment of the key count (nkeys).
There should be corresponding read barriers between the read of nkeys and
dereferences of keys[n] when n is dependent on the value of nkeys.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/keys/gc.c')
-rw-r--r-- | security/keys/gc.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/security/keys/gc.c b/security/keys/gc.c index bf4d8da5a795..a42b45531aac 100644 --- a/security/keys/gc.c +++ b/security/keys/gc.c @@ -145,7 +145,9 @@ static void key_gc_keyring(struct key *keyring, time_t limit) if (!klist) goto unlock_dont_gc; - for (loop = klist->nkeys - 1; loop >= 0; loop--) { + loop = klist->nkeys; + smp_rmb(); + for (loop--; loop >= 0; loop--) { key = klist->keys[loop]; if (test_bit(KEY_FLAG_DEAD, &key->flags) || (key->expiry > 0 && key->expiry <= limit)) |