KEYS: Merge the type-specific data with the payload data

Merge the type-specific data with the payload data into one four-word chunk
as it seems pointless to keep them separate.

Use user_key_payload() for accessing the payloads of overloaded
user-defined keys.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
cc: ecryptfs@vger.kernel.org
cc: linux-ext4@vger.kernel.org
cc: linux-f2fs-devel@lists.sourceforge.net
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-ima-devel@lists.sourceforge.net
This commit is contained in:
David Howells
2015-10-21 14:04:48 +01:00
parent 4adc605edc
commit 146aa8b145
49 changed files with 286 additions and 230 deletions

View File

@@ -20,6 +20,16 @@
MODULE_LICENSE("GPL");
/*
* Layout of key payload words.
*/
enum {
big_key_data,
big_key_path,
big_key_path_2nd_part,
big_key_len,
};
/*
* If the data is under this limit, there's no point creating a shm file to
* hold it as the permanently resident metadata for the shmem fs will be at
@@ -47,7 +57,7 @@ struct key_type key_type_big_key = {
*/
int big_key_preparse(struct key_preparsed_payload *prep)
{
struct path *path = (struct path *)&prep->payload;
struct path *path = (struct path *)&prep->payload.data[big_key_path];
struct file *file;
ssize_t written;
size_t datalen = prep->datalen;
@@ -60,7 +70,7 @@ int big_key_preparse(struct key_preparsed_payload *prep)
/* Set an arbitrary quota */
prep->quotalen = 16;
prep->type_data[1] = (void *)(unsigned long)datalen;
prep->payload.data[big_key_len] = (void *)(unsigned long)datalen;
if (datalen > BIG_KEY_FILE_THRESHOLD) {
/* Create a shmem file to store the data in. This will permit the data
@@ -94,7 +104,8 @@ int big_key_preparse(struct key_preparsed_payload *prep)
if (!data)
return -ENOMEM;
prep->payload[0] = memcpy(data, prep->data, prep->datalen);
prep->payload.data[big_key_data] = data;
memcpy(data, prep->data, prep->datalen);
}
return 0;
@@ -110,10 +121,10 @@ error:
void big_key_free_preparse(struct key_preparsed_payload *prep)
{
if (prep->datalen > BIG_KEY_FILE_THRESHOLD) {
struct path *path = (struct path *)&prep->payload;
struct path *path = (struct path *)&prep->payload.data[big_key_path];
path_put(path);
} else {
kfree(prep->payload[0]);
kfree(prep->payload.data[big_key_data]);
}
}
@@ -123,11 +134,12 @@ void big_key_free_preparse(struct key_preparsed_payload *prep)
*/
void big_key_revoke(struct key *key)
{
struct path *path = (struct path *)&key->payload.data2;
struct path *path = (struct path *)&key->payload.data[big_key_path];
/* clear the quota */
key_payload_reserve(key, 0);
if (key_is_instantiated(key) && key->type_data.x[1] > BIG_KEY_FILE_THRESHOLD)
if (key_is_instantiated(key) &&
(size_t)key->payload.data[big_key_len] > BIG_KEY_FILE_THRESHOLD)
vfs_truncate(path, 0);
}
@@ -136,14 +148,16 @@ void big_key_revoke(struct key *key)
*/
void big_key_destroy(struct key *key)
{
if (key->type_data.x[1] > BIG_KEY_FILE_THRESHOLD) {
struct path *path = (struct path *)&key->payload.data2;
size_t datalen = (size_t)key->payload.data[big_key_len];
if (datalen) {
struct path *path = (struct path *)&key->payload.data[big_key_path];
path_put(path);
path->mnt = NULL;
path->dentry = NULL;
} else {
kfree(key->payload.data);
key->payload.data = NULL;
kfree(key->payload.data[big_key_data]);
key->payload.data[big_key_data] = NULL;
}
}
@@ -152,12 +166,12 @@ void big_key_destroy(struct key *key)
*/
void big_key_describe(const struct key *key, struct seq_file *m)
{
unsigned long datalen = key->type_data.x[1];
size_t datalen = (size_t)key->payload.data[big_key_len];
seq_puts(m, key->description);
if (key_is_instantiated(key))
seq_printf(m, ": %lu [%s]",
seq_printf(m, ": %zu [%s]",
datalen,
datalen > BIG_KEY_FILE_THRESHOLD ? "file" : "buff");
}
@@ -168,14 +182,14 @@ void big_key_describe(const struct key *key, struct seq_file *m)
*/
long big_key_read(const struct key *key, char __user *buffer, size_t buflen)
{
unsigned long datalen = key->type_data.x[1];
size_t datalen = (size_t)key->payload.data[big_key_len];
long ret;
if (!buffer || buflen < datalen)
return datalen;
if (datalen > BIG_KEY_FILE_THRESHOLD) {
struct path *path = (struct path *)&key->payload.data2;
struct path *path = (struct path *)&key->payload.data[big_key_path];
struct file *file;
loff_t pos;
@@ -190,7 +204,8 @@ long big_key_read(const struct key *key, char __user *buffer, size_t buflen)
ret = -EIO;
} else {
ret = datalen;
if (copy_to_user(buffer, key->payload.data, datalen) != 0)
if (copy_to_user(buffer, key->payload.data[big_key_data],
datalen) != 0)
ret = -EFAULT;
}