Commit ca4da5dd authored Jul 27, 2015 by Colin Ian King Committed by James Morris Jul 28, 2015

KEYS: ensure we free the assoc array edit if edit is valid



__key_link_end is not freeing the associated array edit structure
and this leads to a 512 byte memory leak each time an identical
existing key is added with add_key().

The reason the add_key() system call returns okay is that
key_create_or_update() calls __key_link_begin() before checking to see
whether it can update a key directly rather than adding/replacing - which
it turns out it can.  Thus __key_link() is not called through
__key_instantiate_and_link() and __key_link_end() must cancel the edit.

CVE-2015-1333

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

parent cbfe8fa6

security/keys/keyring.c

+5 −3

Original line number	Diff line number	Diff line
		@@ -1181,9 +1181,11 @@ void __key_link_end(struct key *keyring,
		if (index_key->type == &key_type_keyring)
		up_write(&keyring_serialise_link_sem);

		if (edit && !edit->dead_leaf) {
		if (edit) {
		if (!edit->dead_leaf) {
		key_payload_reserve(keyring,
		keyring->datalen - KEYQUOTA_LINK_BYTES);
		}
		assoc_array_cancel_edit(edit);
		}
		up_write(&keyring->sem);

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