提交 494b9ae7 编写于 作者: J James Morris

Merge commit 'tags/keys-fixes-20171018' into fixes-v4.14-rc5

......@@ -57,6 +57,8 @@ struct key *find_asymmetric_key(struct key *keyring,
char *req, *p;
int len;
BUG_ON(!id_0 && !id_1);
if (id_0) {
lookup = id_0->data;
len = id_0->len;
......@@ -105,7 +107,7 @@ struct key *find_asymmetric_key(struct key *keyring,
if (id_0 && id_1) {
const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
if (!kids->id[0]) {
if (!kids->id[1]) {
pr_debug("First ID matches, but second is missing\n");
goto reject;
}
......
......@@ -88,6 +88,9 @@ static int pkcs7_check_authattrs(struct pkcs7_message *msg)
bool want = false;
sinfo = msg->signed_infos;
if (!sinfo)
goto inconsistent;
if (sinfo->authattrs) {
want = true;
msg->have_authattrs = true;
......
......@@ -109,6 +109,11 @@ static int validate_user_key(struct fscrypt_info *crypt_info,
goto out;
}
ukp = user_key_payload_locked(keyring_key);
if (!ukp) {
/* key was revoked before we acquired its semaphore */
res = -EKEYREVOKED;
goto out;
}
if (ukp->datalen != sizeof(struct fscrypt_key)) {
res = -EINVAL;
goto out;
......
......@@ -84,11 +84,16 @@ struct ecryptfs_page_crypt_context {
static inline struct ecryptfs_auth_tok *
ecryptfs_get_encrypted_key_payload_data(struct key *key)
{
if (key->type == &key_type_encrypted)
return (struct ecryptfs_auth_tok *)
(&((struct encrypted_key_payload *)key->payload.data[0])->payload_data);
else
struct encrypted_key_payload *payload;
if (key->type != &key_type_encrypted)
return NULL;
payload = key->payload.data[0];
if (!payload)
return ERR_PTR(-EKEYREVOKED);
return (struct ecryptfs_auth_tok *)payload->payload_data;
}
static inline struct key *ecryptfs_get_encrypted_key(char *sig)
......@@ -114,12 +119,17 @@ static inline struct ecryptfs_auth_tok *
ecryptfs_get_key_payload_data(struct key *key)
{
struct ecryptfs_auth_tok *auth_tok;
struct user_key_payload *ukp;
auth_tok = ecryptfs_get_encrypted_key_payload_data(key);
if (!auth_tok)
return (struct ecryptfs_auth_tok *)user_key_payload_locked(key)->data;
else
if (auth_tok)
return auth_tok;
ukp = user_key_payload_locked(key);
if (!ukp)
return ERR_PTR(-EKEYREVOKED);
return (struct ecryptfs_auth_tok *)ukp->data;
}
#define ECRYPTFS_MAX_KEYSET_SIZE 1024
......
......@@ -459,7 +459,8 @@ static int ecryptfs_verify_version(u16 version)
* @auth_tok_key: key containing the authentication token
* @auth_tok: authentication token
*
* Returns zero on valid auth tok; -EINVAL otherwise
* Returns zero on valid auth tok; -EINVAL if the payload is invalid; or
* -EKEYREVOKED if the key was revoked before we acquired its semaphore.
*/
static int
ecryptfs_verify_auth_tok_from_key(struct key *auth_tok_key,
......@@ -468,6 +469,12 @@ ecryptfs_verify_auth_tok_from_key(struct key *auth_tok_key,
int rc = 0;
(*auth_tok) = ecryptfs_get_key_payload_data(auth_tok_key);
if (IS_ERR(*auth_tok)) {
rc = PTR_ERR(*auth_tok);
*auth_tok = NULL;
goto out;
}
if (ecryptfs_verify_version((*auth_tok)->version)) {
printk(KERN_ERR "Data structure version mismatch. Userspace "
"tools must match eCryptfs kernel module with major "
......
......@@ -331,6 +331,13 @@ static void fscache_objlist_config(struct fscache_objlist_data *data)
rcu_read_lock();
confkey = user_key_payload_rcu(key);
if (!confkey) {
/* key was revoked */
rcu_read_unlock();
key_put(key);
goto no_config;
}
buf = confkey->data;
for (len = confkey->datalen - 1; len >= 0; len--) {
......
......@@ -138,6 +138,11 @@ struct key_restriction {
struct key_type *keytype;
};
enum key_state {
KEY_IS_UNINSTANTIATED,
KEY_IS_POSITIVE, /* Positively instantiated */
};
/*****************************************************************************/
/*
* authentication token / access credential / keyring
......@@ -169,6 +174,7 @@ struct key {
* - may not match RCU dereferenced payload
* - payload should contain own length
*/
short state; /* Key state (+) or rejection error (-) */
#ifdef KEY_DEBUGGING
unsigned magic;
......@@ -176,18 +182,16 @@ struct key {
#endif
unsigned long flags; /* status flags (change with bitops) */
#define KEY_FLAG_INSTANTIATED 0 /* set if key has been instantiated */
#define KEY_FLAG_DEAD 1 /* set if key type has been deleted */
#define KEY_FLAG_REVOKED 2 /* set if key had been revoked */
#define KEY_FLAG_IN_QUOTA 3 /* set if key consumes quota */
#define KEY_FLAG_USER_CONSTRUCT 4 /* set if key is being constructed in userspace */
#define KEY_FLAG_NEGATIVE 5 /* set if key is negative */
#define KEY_FLAG_ROOT_CAN_CLEAR 6 /* set if key can be cleared by root without permission */
#define KEY_FLAG_INVALIDATED 7 /* set if key has been invalidated */
#define KEY_FLAG_BUILTIN 8 /* set if key is built in to the kernel */
#define KEY_FLAG_ROOT_CAN_INVAL 9 /* set if key can be invalidated by root without permission */
#define KEY_FLAG_KEEP 10 /* set if key should not be removed */
#define KEY_FLAG_UID_KEYRING 11 /* set if key is a user or user session keyring */
#define KEY_FLAG_DEAD 0 /* set if key type has been deleted */
#define KEY_FLAG_REVOKED 1 /* set if key had been revoked */
#define KEY_FLAG_IN_QUOTA 2 /* set if key consumes quota */
#define KEY_FLAG_USER_CONSTRUCT 3 /* set if key is being constructed in userspace */
#define KEY_FLAG_ROOT_CAN_CLEAR 4 /* set if key can be cleared by root without permission */
#define KEY_FLAG_INVALIDATED 5 /* set if key has been invalidated */
#define KEY_FLAG_BUILTIN 6 /* set if key is built in to the kernel */
#define KEY_FLAG_ROOT_CAN_INVAL 7 /* set if key can be invalidated by root without permission */
#define KEY_FLAG_KEEP 8 /* set if key should not be removed */
#define KEY_FLAG_UID_KEYRING 9 /* set if key is a user or user session keyring */
/* the key type and key description string
* - the desc is used to match a key against search criteria
......@@ -213,7 +217,6 @@ struct key {
struct list_head name_link;
struct assoc_array keys;
};
int reject_error;
};
/* This is set on a keyring to restrict the addition of a link to a key
......@@ -353,17 +356,27 @@ extern void key_set_timeout(struct key *, unsigned);
#define KEY_NEED_SETATTR 0x20 /* Require permission to change attributes */
#define KEY_NEED_ALL 0x3f /* All the above permissions */
static inline short key_read_state(const struct key *key)
{
/* Barrier versus mark_key_instantiated(). */
return smp_load_acquire(&key->state);
}
/**
* key_is_instantiated - Determine if a key has been positively instantiated
* key_is_positive - Determine if a key has been positively instantiated
* @key: The key to check.
*
* Return true if the specified key has been positively instantiated, false
* otherwise.
*/
static inline bool key_is_instantiated(const struct key *key)
static inline bool key_is_positive(const struct key *key)
{
return key_read_state(key) == KEY_IS_POSITIVE;
}
static inline bool key_is_negative(const struct key *key)
{
return test_bit(KEY_FLAG_INSTANTIATED, &key->flags) &&
!test_bit(KEY_FLAG_NEGATIVE, &key->flags);
return key_read_state(key) < 0;
}
#define dereference_key_rcu(KEY) \
......
......@@ -87,6 +87,12 @@ static int digsig_verify_rsa(struct key *key,
down_read(&key->sem);
ukp = user_key_payload_locked(key);
if (!ukp) {
/* key was revoked before we acquired its semaphore */
err = -EKEYREVOKED;
goto err1;
}
if (ukp->datalen < sizeof(*pkh))
goto err1;
......
......@@ -224,7 +224,7 @@ static int dns_resolver_match_preparse(struct key_match_data *match_data)
static void dns_resolver_describe(const struct key *key, struct seq_file *m)
{
seq_puts(m, key->description);
if (key_is_instantiated(key)) {
if (key_is_positive(key)) {
int err = PTR_ERR(key->payload.data[dns_key_error]);
if (err)
......
......@@ -45,6 +45,7 @@ config BIG_KEYS
bool "Large payload keys"
depends on KEYS
depends on TMPFS
select CRYPTO
select CRYPTO_AES
select CRYPTO_GCM
help
......
......@@ -247,7 +247,7 @@ void big_key_revoke(struct key *key)
/* clear the quota */
key_payload_reserve(key, 0);
if (key_is_instantiated(key) &&
if (key_is_positive(key) &&
(size_t)key->payload.data[big_key_len] > BIG_KEY_FILE_THRESHOLD)
vfs_truncate(path, 0);
}
......@@ -279,7 +279,7 @@ void big_key_describe(const struct key *key, struct seq_file *m)
seq_puts(m, key->description);
if (key_is_instantiated(key))
if (key_is_positive(key))
seq_printf(m, ": %zu [%s]",
datalen,
datalen > BIG_KEY_FILE_THRESHOLD ? "file" : "buff");
......
......@@ -309,6 +309,13 @@ static struct key *request_user_key(const char *master_desc, const u8 **master_k
down_read(&ukey->sem);
upayload = user_key_payload_locked(ukey);
if (!upayload) {
/* key was revoked before we acquired its semaphore */
up_read(&ukey->sem);
key_put(ukey);
ukey = ERR_PTR(-EKEYREVOKED);
goto error;
}
*master_key = upayload->data;
*master_keylen = upayload->datalen;
error:
......@@ -847,7 +854,7 @@ static int encrypted_update(struct key *key, struct key_preparsed_payload *prep)
size_t datalen = prep->datalen;
int ret = 0;
if (test_bit(KEY_FLAG_NEGATIVE, &key->flags))
if (key_is_negative(key))
return -ENOKEY;
if (datalen <= 0 || datalen > 32767 || !prep->data)
return -EINVAL;
......
......@@ -129,15 +129,15 @@ static noinline void key_gc_unused_keys(struct list_head *keys)
while (!list_empty(keys)) {
struct key *key =
list_entry(keys->next, struct key, graveyard_link);
short state = key->state;
list_del(&key->graveyard_link);
kdebug("- %u", key->serial);
key_check(key);
/* Throw away the key data if the key is instantiated */
if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags) &&
!test_bit(KEY_FLAG_NEGATIVE, &key->flags) &&
key->type->destroy)
if (state == KEY_IS_POSITIVE && key->type->destroy)
key->type->destroy(key);
security_key_free(key);
......@@ -151,7 +151,7 @@ static noinline void key_gc_unused_keys(struct list_head *keys)
}
atomic_dec(&key->user->nkeys);
if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
if (state != KEY_IS_UNINSTANTIATED)
atomic_dec(&key->user->nikeys);
key_user_put(key->user);
......
......@@ -401,6 +401,18 @@ int key_payload_reserve(struct key *key, size_t datalen)
}
EXPORT_SYMBOL(key_payload_reserve);
/*
* Change the key state to being instantiated.
*/
static void mark_key_instantiated(struct key *key, int reject_error)
{
/* Commit the payload before setting the state; barrier versus
* key_read_state().
*/
smp_store_release(&key->state,
(reject_error < 0) ? reject_error : KEY_IS_POSITIVE);
}
/*
* Instantiate a key and link it into the target keyring atomically. Must be
* called with the target keyring's semaphore writelocked. The target key's
......@@ -424,14 +436,14 @@ static int __key_instantiate_and_link(struct key *key,
mutex_lock(&key_construction_mutex);
/* can't instantiate twice */
if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
if (key->state == KEY_IS_UNINSTANTIATED) {
/* instantiate the key */
ret = key->type->instantiate(key, prep);
if (ret == 0) {
/* mark the key as being instantiated */
atomic_inc(&key->user->nikeys);
set_bit(KEY_FLAG_INSTANTIATED, &key->flags);
mark_key_instantiated(key, 0);
if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags))
awaken = 1;
......@@ -577,13 +589,10 @@ int key_reject_and_link(struct key *key,
mutex_lock(&key_construction_mutex);
/* can't instantiate twice */
if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
if (key->state == KEY_IS_UNINSTANTIATED) {
/* mark the key as being negatively instantiated */
atomic_inc(&key->user->nikeys);
key->reject_error = -error;
smp_wmb();
set_bit(KEY_FLAG_NEGATIVE, &key->flags);
set_bit(KEY_FLAG_INSTANTIATED, &key->flags);
mark_key_instantiated(key, -error);
now = current_kernel_time();
key->expiry = now.tv_sec + timeout;
key_schedule_gc(key->expiry + key_gc_delay);
......@@ -752,8 +761,8 @@ static inline key_ref_t __key_update(key_ref_t key_ref,
ret = key->type->update(key, prep);
if (ret == 0)
/* updating a negative key instantiates it */
clear_bit(KEY_FLAG_NEGATIVE, &key->flags);
/* Updating a negative key positively instantiates it */
mark_key_instantiated(key, 0);
up_write(&key->sem);
......@@ -936,6 +945,16 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
*/
__key_link_end(keyring, &index_key, edit);
key = key_ref_to_ptr(key_ref);
if (test_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) {
ret = wait_for_key_construction(key, true);
if (ret < 0) {
key_ref_put(key_ref);
key_ref = ERR_PTR(ret);
goto error_free_prep;
}
}
key_ref = __key_update(key_ref, &prep);
goto error_free_prep;
}
......@@ -986,8 +1005,8 @@ int key_update(key_ref_t key_ref, const void *payload, size_t plen)
ret = key->type->update(key, &prep);
if (ret == 0)
/* updating a negative key instantiates it */
clear_bit(KEY_FLAG_NEGATIVE, &key->flags);
/* Updating a negative key positively instantiates it */
mark_key_instantiated(key, 0);
up_write(&key->sem);
......
......@@ -766,10 +766,9 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
key = key_ref_to_ptr(key_ref);
if (test_bit(KEY_FLAG_NEGATIVE, &key->flags)) {
ret = -ENOKEY;
goto error2;
}
ret = key_read_state(key);
if (ret < 0)
goto error2; /* Negatively instantiated */
/* see if we can read it directly */
ret = key_permission(key_ref, KEY_NEED_READ);
......@@ -901,7 +900,7 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group)
atomic_dec(&key->user->nkeys);
atomic_inc(&newowner->nkeys);
if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
if (key->state != KEY_IS_UNINSTANTIATED) {
atomic_dec(&key->user->nikeys);
atomic_inc(&newowner->nikeys);
}
......
......@@ -414,7 +414,7 @@ static void keyring_describe(const struct key *keyring, struct seq_file *m)
else
seq_puts(m, "[anon]");
if (key_is_instantiated(keyring)) {
if (key_is_positive(keyring)) {
if (keyring->keys.nr_leaves_on_tree != 0)
seq_printf(m, ": %lu", keyring->keys.nr_leaves_on_tree);
else
......@@ -553,7 +553,8 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
{
struct keyring_search_context *ctx = iterator_data;
const struct key *key = keyring_ptr_to_key(object);
unsigned long kflags = key->flags;
unsigned long kflags = READ_ONCE(key->flags);
short state = READ_ONCE(key->state);
kenter("{%d}", key->serial);
......@@ -565,6 +566,8 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
/* skip invalidated, revoked and expired keys */
if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) {
time_t expiry = READ_ONCE(key->expiry);
if (kflags & ((1 << KEY_FLAG_INVALIDATED) |
(1 << KEY_FLAG_REVOKED))) {
ctx->result = ERR_PTR(-EKEYREVOKED);
......@@ -572,7 +575,7 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
goto skipped;
}
if (key->expiry && ctx->now.tv_sec >= key->expiry) {
if (expiry && ctx->now.tv_sec >= expiry) {
if (!(ctx->flags & KEYRING_SEARCH_SKIP_EXPIRED))
ctx->result = ERR_PTR(-EKEYEXPIRED);
kleave(" = %d [expire]", ctx->skipped_ret);
......@@ -597,9 +600,8 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) {
/* we set a different error code if we pass a negative key */
if (kflags & (1 << KEY_FLAG_NEGATIVE)) {
smp_rmb();
ctx->result = ERR_PTR(key->reject_error);
if (state < 0) {
ctx->result = ERR_PTR(state);
kleave(" = %d [neg]", ctx->skipped_ret);
goto skipped;
}
......
......@@ -88,7 +88,8 @@ EXPORT_SYMBOL(key_task_permission);
*/
int key_validate(const struct key *key)
{
unsigned long flags = key->flags;
unsigned long flags = READ_ONCE(key->flags);
time_t expiry = READ_ONCE(key->expiry);
if (flags & (1 << KEY_FLAG_INVALIDATED))
return -ENOKEY;
......@@ -99,9 +100,9 @@ int key_validate(const struct key *key)
return -EKEYREVOKED;
/* check it hasn't expired */
if (key->expiry) {
if (expiry) {
struct timespec now = current_kernel_time();
if (now.tv_sec >= key->expiry)
if (now.tv_sec >= expiry)
return -EKEYEXPIRED;
}
......
......@@ -179,9 +179,12 @@ static int proc_keys_show(struct seq_file *m, void *v)
struct rb_node *_p = v;
struct key *key = rb_entry(_p, struct key, serial_node);
struct timespec now;
time_t expiry;
unsigned long timo;
unsigned long flags;
key_ref_t key_ref, skey_ref;
char xbuf[16];
short state;
int rc;
struct keyring_search_context ctx = {
......@@ -217,12 +220,13 @@ static int proc_keys_show(struct seq_file *m, void *v)
rcu_read_lock();
/* come up with a suitable timeout value */
if (key->expiry == 0) {
expiry = READ_ONCE(key->expiry);
if (expiry == 0) {
memcpy(xbuf, "perm", 5);
} else if (now.tv_sec >= key->expiry) {
} else if (now.tv_sec >= expiry) {
memcpy(xbuf, "expd", 5);
} else {
timo = key->expiry - now.tv_sec;
timo = expiry - now.tv_sec;
if (timo < 60)
sprintf(xbuf, "%lus", timo);
......@@ -236,18 +240,21 @@ static int proc_keys_show(struct seq_file *m, void *v)
sprintf(xbuf, "%luw", timo / (60*60*24*7));
}
#define showflag(KEY, LETTER, FLAG) \
(test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
state = key_read_state(key);
#define showflag(FLAGS, LETTER, FLAG) \
((FLAGS & (1 << FLAG)) ? LETTER : '-')
flags = READ_ONCE(key->flags);
seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
key->serial,
showflag(key, 'I', KEY_FLAG_INSTANTIATED),
showflag(key, 'R', KEY_FLAG_REVOKED),
showflag(key, 'D', KEY_FLAG_DEAD),
showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
showflag(key, 'N', KEY_FLAG_NEGATIVE),
showflag(key, 'i', KEY_FLAG_INVALIDATED),
state != KEY_IS_UNINSTANTIATED ? 'I' : '-',
showflag(flags, 'R', KEY_FLAG_REVOKED),
showflag(flags, 'D', KEY_FLAG_DEAD),
showflag(flags, 'Q', KEY_FLAG_IN_QUOTA),
showflag(flags, 'U', KEY_FLAG_USER_CONSTRUCT),
state < 0 ? 'N' : '-',
showflag(flags, 'i', KEY_FLAG_INVALIDATED),
refcount_read(&key->usage),
xbuf,
key->perm,
......
......@@ -730,7 +730,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
ret = -EIO;
if (!(lflags & KEY_LOOKUP_PARTIAL) &&
!test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
key_read_state(key) == KEY_IS_UNINSTANTIATED)
goto invalid_key;
/* check the permissions */
......
......@@ -595,10 +595,9 @@ int wait_for_key_construction(struct key *key, bool intr)
intr ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
if (ret)
return -ERESTARTSYS;
if (test_bit(KEY_FLAG_NEGATIVE, &key->flags)) {
smp_rmb();
return key->reject_error;
}
ret = key_read_state(key);
if (ret < 0)
return ret;
return key_validate(key);
}
EXPORT_SYMBOL(wait_for_key_construction);
......
......@@ -73,7 +73,7 @@ static void request_key_auth_describe(const struct key *key,
seq_puts(m, "key:");
seq_puts(m, key->description);
if (key_is_instantiated(key))
if (key_is_positive(key))
seq_printf(m, " pid:%d ci:%zu", rka->pid, rka->callout_len);
}
......
......@@ -1066,7 +1066,7 @@ static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
char *datablob;
int ret = 0;
if (test_bit(KEY_FLAG_NEGATIVE, &key->flags))
if (key_is_negative(key))
return -ENOKEY;
p = key->payload.data[0];
if (!p->migratable)
......
......@@ -114,7 +114,7 @@ int user_update(struct key *key, struct key_preparsed_payload *prep)
/* attach the new data, displacing the old */
key->expiry = prep->expiry;
if (!test_bit(KEY_FLAG_NEGATIVE, &key->flags))
if (key_is_positive(key))
zap = dereference_key_locked(key);
rcu_assign_keypointer(key, prep->payload.data[0]);
prep->payload.data[0] = NULL;
......@@ -162,7 +162,7 @@ EXPORT_SYMBOL_GPL(user_destroy);
void user_describe(const struct key *key, struct seq_file *m)
{
seq_puts(m, key->description);
if (key_is_instantiated(key))
if (key_is_positive(key))
seq_printf(m, ": %u", key->datalen);
}
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册