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-rw-r--r--Documentation/security/keys.txt17
-rw-r--r--include/linux/key.h3
-rw-r--r--include/linux/keyctl.h1
-rw-r--r--security/keys/compat.c3
-rw-r--r--security/keys/gc.c21
-rw-r--r--security/keys/internal.h15
-rw-r--r--security/keys/key.c22
-rw-r--r--security/keys/keyctl.c34
-rw-r--r--security/keys/keyring.c25
-rw-r--r--security/keys/permission.c15
-rw-r--r--security/keys/proc.c3
11 files changed, 131 insertions, 28 deletions
diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt
index d389acd31e19..aa0dbd74b71b 100644
--- a/Documentation/security/keys.txt
+++ b/Documentation/security/keys.txt
@@ -805,6 +805,23 @@ The keyctl syscall functions are:
kernel and resumes executing userspace.
+ (*) Invalidate a key.
+
+ long keyctl(KEYCTL_INVALIDATE, key_serial_t key);
+
+ This function marks a key as being invalidated and then wakes up the
+ garbage collector. The garbage collector immediately removes invalidated
+ keys from all keyrings and deletes the key when its reference count
+ reaches zero.
+
+ Keys that are marked invalidated become invisible to normal key operations
+ immediately, though they are still visible in /proc/keys until deleted
+ (they're marked with an 'i' flag).
+
+ A process must have search permission on the key for this function to be
+ successful.
+
+
===============
KERNEL SERVICES
===============
diff --git a/include/linux/key.h b/include/linux/key.h
index 13c0dcd8ee48..b145b054b3e0 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -160,6 +160,7 @@ struct key {
#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 */
/* the description string
* - this is used to match a key against search criteria
@@ -203,6 +204,7 @@ extern struct key *key_alloc(struct key_type *type,
#define KEY_ALLOC_NOT_IN_QUOTA 0x0002 /* not in quota */
extern void key_revoke(struct key *key);
+extern void key_invalidate(struct key *key);
extern void key_put(struct key *key);
static inline struct key *key_get(struct key *key)
@@ -323,6 +325,7 @@ extern void key_init(void);
#define key_serial(k) 0
#define key_get(k) ({ NULL; })
#define key_revoke(k) do { } while(0)
+#define key_invalidate(k) do { } while(0)
#define key_put(k) do { } while(0)
#define key_ref_put(k) do { } while(0)
#define make_key_ref(k, p) NULL
diff --git a/include/linux/keyctl.h b/include/linux/keyctl.h
index 9b0b865ce622..c9b7f4faf97a 100644
--- a/include/linux/keyctl.h
+++ b/include/linux/keyctl.h
@@ -55,5 +55,6 @@
#define KEYCTL_SESSION_TO_PARENT 18 /* apply session keyring to parent process */
#define KEYCTL_REJECT 19 /* reject a partially constructed key */
#define KEYCTL_INSTANTIATE_IOV 20 /* instantiate a partially constructed key */
+#define KEYCTL_INVALIDATE 21 /* invalidate a key */
#endif /* _LINUX_KEYCTL_H */
diff --git a/security/keys/compat.c b/security/keys/compat.c
index 4c48e13448f8..fab4f8dda6c6 100644
--- a/security/keys/compat.c
+++ b/security/keys/compat.c
@@ -135,6 +135,9 @@ asmlinkage long compat_sys_keyctl(u32 option,
return compat_keyctl_instantiate_key_iov(
arg2, compat_ptr(arg3), arg4, arg5);
+ case KEYCTL_INVALIDATE:
+ return keyctl_invalidate_key(arg2);
+
default:
return -EOPNOTSUPP;
}
diff --git a/security/keys/gc.c b/security/keys/gc.c
index adddaa258d50..61ab7c82ebb1 100644
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -72,6 +72,15 @@ void key_schedule_gc(time_t gc_at)
}
/*
+ * Schedule a dead links collection run.
+ */
+void key_schedule_gc_links(void)
+{
+ set_bit(KEY_GC_KEY_EXPIRED, &key_gc_flags);
+ queue_work(system_nrt_wq, &key_gc_work);
+}
+
+/*
* Some key's cleanup time was met after it expired, so we need to get the
* reaper to go through a cycle finding expired keys.
*/
@@ -79,8 +88,7 @@ static void key_gc_timer_func(unsigned long data)
{
kenter("");
key_gc_next_run = LONG_MAX;
- set_bit(KEY_GC_KEY_EXPIRED, &key_gc_flags);
- queue_work(system_nrt_wq, &key_gc_work);
+ key_schedule_gc_links();
}
/*
@@ -131,12 +139,12 @@ void key_gc_keytype(struct key_type *ktype)
static void key_gc_keyring(struct key *keyring, time_t limit)
{
struct keyring_list *klist;
- struct key *key;
int loop;
kenter("%x", key_serial(keyring));
- if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+ if (keyring->flags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED)))
goto dont_gc;
/* scan the keyring looking for dead keys */
@@ -148,9 +156,8 @@ static void key_gc_keyring(struct key *keyring, time_t limit)
loop = klist->nkeys;
smp_rmb();
for (loop--; loop >= 0; loop--) {
- key = rcu_dereference(klist->keys[loop]);
- if (test_bit(KEY_FLAG_DEAD, &key->flags) ||
- (key->expiry > 0 && key->expiry <= limit))
+ struct key *key = rcu_dereference(klist->keys[loop]);
+ if (key_is_dead(key, limit))
goto do_gc;
}
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 65647f825584..f711b094ed41 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -152,7 +152,8 @@ extern long join_session_keyring(const char *name);
extern struct work_struct key_gc_work;
extern unsigned key_gc_delay;
extern void keyring_gc(struct key *keyring, time_t limit);
-extern void key_schedule_gc(time_t expiry_at);
+extern void key_schedule_gc(time_t gc_at);
+extern void key_schedule_gc_links(void);
extern void key_gc_keytype(struct key_type *ktype);
extern int key_task_permission(const key_ref_t key_ref,
@@ -197,6 +198,17 @@ extern struct key *request_key_auth_new(struct key *target,
extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
/*
+ * Determine whether a key is dead.
+ */
+static inline bool key_is_dead(struct key *key, time_t limit)
+{
+ return
+ key->flags & ((1 << KEY_FLAG_DEAD) |
+ (1 << KEY_FLAG_INVALIDATED)) ||
+ (key->expiry > 0 && key->expiry <= limit);
+}
+
+/*
* keyctl() functions
*/
extern long keyctl_get_keyring_ID(key_serial_t, int);
@@ -225,6 +237,7 @@ extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
extern long keyctl_instantiate_key_iov(key_serial_t,
const struct iovec __user *,
unsigned, key_serial_t);
+extern long keyctl_invalidate_key(key_serial_t);
extern long keyctl_instantiate_key_common(key_serial_t,
const struct iovec __user *,
diff --git a/security/keys/key.c b/security/keys/key.c
index dc628941ecd3..c9bf66ac36e0 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -955,6 +955,28 @@ void key_revoke(struct key *key)
EXPORT_SYMBOL(key_revoke);
/**
+ * key_invalidate - Invalidate a key.
+ * @key: The key to be invalidated.
+ *
+ * Mark a key as being invalidated and have it cleaned up immediately. The key
+ * is ignored by all searches and other operations from this point.
+ */
+void key_invalidate(struct key *key)
+{
+ kenter("%d", key_serial(key));
+
+ key_check(key);
+
+ if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
+ down_write_nested(&key->sem, 1);
+ if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags))
+ key_schedule_gc_links();
+ up_write(&key->sem);
+ }
+}
+EXPORT_SYMBOL(key_invalidate);
+
+/**
* register_key_type - Register a type of key.
* @ktype: The new key type.
*
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index fb767c6cd99f..ddb3e05bc5fc 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -375,6 +375,37 @@ error:
}
/*
+ * Invalidate a key.
+ *
+ * The key must be grant the caller Invalidate permission for this to work.
+ * The key and any links to the key will be automatically garbage collected
+ * immediately.
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_invalidate_key(key_serial_t id)
+{
+ key_ref_t key_ref;
+ long ret;
+
+ kenter("%d", id);
+
+ key_ref = lookup_user_key(id, 0, KEY_SEARCH);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+
+ key_invalidate(key_ref_to_ptr(key_ref));
+ ret = 0;
+
+ key_ref_put(key_ref);
+error:
+ kleave(" = %ld", ret);
+ return ret;
+}
+
+/*
* Clear the specified keyring, creating an empty process keyring if one of the
* special keyring IDs is used.
*
@@ -1622,6 +1653,9 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3,
(unsigned) arg4,
(key_serial_t) arg5);
+ case KEYCTL_INVALIDATE:
+ return keyctl_invalidate_key((key_serial_t) arg2);
+
default:
return -EOPNOTSUPP;
}
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 89d02cfb00c2..7445875f6818 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -382,13 +382,17 @@ key_ref_t keyring_search_aux(key_ref_t keyring_ref,
/* otherwise, the top keyring must not be revoked, expired, or
* negatively instantiated if we are to search it */
key_ref = ERR_PTR(-EAGAIN);
- if (kflags & ((1 << KEY_FLAG_REVOKED) | (1 << KEY_FLAG_NEGATIVE)) ||
+ if (kflags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED) |
+ (1 << KEY_FLAG_NEGATIVE)) ||
(keyring->expiry && now.tv_sec >= keyring->expiry))
goto error_2;
/* start processing a new keyring */
descend:
- if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+ kflags = keyring->flags;
+ if (kflags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED)))
goto not_this_keyring;
keylist = rcu_dereference(keyring->payload.subscriptions);
@@ -406,9 +410,10 @@ descend:
if (key->type != type)
continue;
- /* skip revoked keys and expired keys */
+ /* skip invalidated, revoked and expired keys */
if (!no_state_check) {
- if (kflags & (1 << KEY_FLAG_REVOKED))
+ if (kflags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED)))
continue;
if (key->expiry && now.tv_sec >= key->expiry)
@@ -559,7 +564,8 @@ key_ref_t __keyring_search_one(key_ref_t keyring_ref,
key->type->match(key, description)) &&
key_permission(make_key_ref(key, possessed),
perm) == 0 &&
- !test_bit(KEY_FLAG_REVOKED, &key->flags)
+ !(key->flags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED)))
)
goto found;
}
@@ -1177,15 +1183,6 @@ static void keyring_revoke(struct key *keyring)
}
/*
- * Determine whether a key is dead.
- */
-static bool key_is_dead(struct key *key, time_t limit)
-{
- return test_bit(KEY_FLAG_DEAD, &key->flags) ||
- (key->expiry > 0 && key->expiry <= limit);
-}
-
-/*
* Collect garbage from the contents of a keyring, replacing the old list with
* a new one with the pointers all shuffled down.
*
diff --git a/security/keys/permission.c b/security/keys/permission.c
index c35b5229e3cd..5f4c00c0947d 100644
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -87,20 +87,25 @@ EXPORT_SYMBOL(key_task_permission);
* key_validate - Validate a key.
* @key: The key to be validated.
*
- * Check that a key is valid, returning 0 if the key is okay, -EKEYREVOKED if
- * the key's type has been removed or if the key has been revoked or
- * -EKEYEXPIRED if the key has expired.
+ * Check that a key is valid, returning 0 if the key is okay, -ENOKEY if the
+ * key is invalidated, -EKEYREVOKED if the key's type has been removed or if
+ * the key has been revoked or -EKEYEXPIRED if the key has expired.
*/
int key_validate(struct key *key)
{
struct timespec now;
+ unsigned long flags = key->flags;
int ret = 0;
if (key) {
+ ret = -ENOKEY;
+ if (flags & (1 << KEY_FLAG_INVALIDATED))
+ goto error;
+
/* check it's still accessible */
ret = -EKEYREVOKED;
- if (test_bit(KEY_FLAG_REVOKED, &key->flags) ||
- test_bit(KEY_FLAG_DEAD, &key->flags))
+ if (flags & ((1 << KEY_FLAG_REVOKED) |
+ (1 << KEY_FLAG_DEAD)))
goto error;
/* check it hasn't expired */
diff --git a/security/keys/proc.c b/security/keys/proc.c
index 49bbc97943ad..30d1ddfd9cef 100644
--- a/security/keys/proc.c
+++ b/security/keys/proc.c
@@ -242,7 +242,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
#define showflag(KEY, LETTER, FLAG) \
(test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
- seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
+ 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),
@@ -250,6 +250,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
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),
atomic_read(&key->usage),
xbuf,
key->perm,
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 08:20:00 +0000