KEYS: big_key: Use key preparsing
Make use of key preparsing in the big key type so that quota size determination
can take place prior to keyring locking when a key is being added.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
diff --git a/security/keys/big_key.c b/security/keys/big_key.c
index 8137b27..c2f91a0 100644
--- a/security/keys/big_key.c
+++ b/security/keys/big_key.c
@@ -34,7 +34,9 @@
struct key_type key_type_big_key = {
.name = "big_key",
.def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
- .instantiate = big_key_instantiate,
+ .preparse = big_key_preparse,
+ .free_preparse = big_key_free_preparse,
+ .instantiate = generic_key_instantiate,
.match = user_match,
.revoke = big_key_revoke,
.destroy = big_key_destroy,
@@ -43,11 +45,11 @@
};
/*
- * Instantiate a big key
+ * Preparse a big key
*/
-int big_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
+int big_key_preparse(struct key_preparsed_payload *prep)
{
- struct path *path = (struct path *)&key->payload.data2;
+ struct path *path = (struct path *)&prep->payload;
struct file *file;
ssize_t written;
size_t datalen = prep->datalen;
@@ -58,11 +60,9 @@
goto error;
/* Set an arbitrary quota */
- ret = key_payload_reserve(key, 16);
- if (ret < 0)
- goto error;
+ prep->quotalen = 16;
- key->type_data.x[1] = datalen;
+ prep->type_data[1] = (void *)(unsigned long)datalen;
if (datalen > BIG_KEY_FILE_THRESHOLD) {
/* Create a shmem file to store the data in. This will permit the data
@@ -73,7 +73,7 @@
file = shmem_kernel_file_setup("", datalen, 0);
if (IS_ERR(file)) {
ret = PTR_ERR(file);
- goto err_quota;
+ goto error;
}
written = kernel_write(file, prep->data, prep->datalen, 0);
@@ -93,24 +93,33 @@
} else {
/* Just store the data in a buffer */
void *data = kmalloc(datalen, GFP_KERNEL);
- if (!data) {
- ret = -ENOMEM;
- goto err_quota;
- }
+ if (!data)
+ return -ENOMEM;
- key->payload.data = memcpy(data, prep->data, prep->datalen);
+ prep->payload[0] = memcpy(data, prep->data, prep->datalen);
}
return 0;
err_fput:
fput(file);
-err_quota:
- key_payload_reserve(key, 0);
error:
return ret;
}
/*
+ * Clear preparsement.
+ */
+void big_key_free_preparse(struct key_preparsed_payload *prep)
+{
+ if (prep->datalen > BIG_KEY_FILE_THRESHOLD) {
+ struct path *path = (struct path *)&prep->payload;
+ path_put(path);
+ } else {
+ kfree(prep->payload[0]);
+ }
+}
+
+/*
* dispose of the links from a revoked keyring
* - called with the key sem write-locked
*/