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-rw-r--r--security/keys/gc.c2
-rw-r--r--security/keys/internal.h10
-rw-r--r--security/keys/key.c5
-rw-r--r--security/keys/keyctl.c8
-rw-r--r--security/keys/keyring.c263
-rw-r--r--security/keys/persistent.c10
-rw-r--r--security/keys/proc.c3
-rw-r--r--security/keys/process_keys.c262
-rw-r--r--security/keys/request_key.c62
-rw-r--r--security/keys/request_key_auth.c3
10 files changed, 387 insertions, 241 deletions
diff --git a/security/keys/gc.c b/security/keys/gc.c
index 44e58a3e5663..671dd730ecfc 100644
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -150,7 +150,7 @@ static noinline void key_gc_unused_keys(struct list_head *keys)
atomic_dec(&key->user->nikeys);
key_user_put(key->user);
-
+ key_put_tag(key->domain_tag);
kfree(key->description);
memzero_explicit(key, sizeof(*key));
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 663f291e30d4..c039373488bd 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -85,7 +85,7 @@ extern spinlock_t key_serial_lock;
extern struct mutex key_construction_mutex;
extern wait_queue_head_t request_key_conswq;
-
+extern void key_set_index_key(struct keyring_index_key *index_key);
extern struct key_type *key_type_lookup(const char *type);
extern void key_type_put(struct key_type *ktype);
@@ -123,6 +123,7 @@ struct keyring_search_context {
#define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */
#define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */
#define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */
+#define KEYRING_SEARCH_RECURSE 0x0040 /* Search child keyrings also */
int (*iterator)(const void *object, void *iterator_data);
@@ -143,13 +144,15 @@ extern key_ref_t search_process_keyrings_rcu(struct keyring_search_context *ctx)
extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);
-extern int install_user_keyrings(void);
+extern int look_up_user_keyrings(struct key **, struct key **);
+extern struct key *get_user_session_keyring_rcu(const struct cred *);
extern int install_thread_keyring_to_cred(struct cred *);
extern int install_process_keyring_to_cred(struct cred *);
extern int install_session_keyring_to_cred(struct cred *, struct key *);
extern struct key *request_key_and_link(struct key_type *type,
const char *description,
+ struct key_tag *domain_tag,
const void *callout_info,
size_t callout_len,
void *aux,
@@ -203,7 +206,8 @@ static inline bool key_is_dead(const struct key *key, time64_t limit)
return
key->flags & ((1 << KEY_FLAG_DEAD) |
(1 << KEY_FLAG_INVALIDATED)) ||
- (key->expiry > 0 && key->expiry <= limit);
+ (key->expiry > 0 && key->expiry <= limit) ||
+ key->domain_tag->removed;
}
/*
diff --git a/security/keys/key.c b/security/keys/key.c
index 85dddc0190a7..764f4c57913e 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -281,11 +281,12 @@ struct key *key_alloc(struct key_type *type, const char *desc,
key->index_key.description = kmemdup(desc, desclen + 1, GFP_KERNEL);
if (!key->index_key.description)
goto no_memory_3;
+ key->index_key.type = type;
+ key_set_index_key(&key->index_key);
refcount_set(&key->usage, 1);
init_rwsem(&key->sem);
lockdep_set_class(&key->sem, &type->lock_class);
- key->index_key.type = type;
key->user = user;
key->quotalen = quotalen;
key->datalen = type->def_datalen;
@@ -312,6 +313,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
goto security_error;
/* publish the key by giving it a serial number */
+ refcount_inc(&key->domain_tag->usage);
atomic_inc(&user->nkeys);
key_alloc_serial(key);
@@ -864,6 +866,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
goto error_free_prep;
}
index_key.desc_len = strlen(index_key.description);
+ key_set_index_key(&index_key);
ret = __key_link_lock(keyring, &index_key);
if (ret < 0) {
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 741e4ba382df..9b898c969558 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -26,7 +26,7 @@
#define KEY_MAX_DESC_SIZE 4096
-static const unsigned char keyrings_capabilities[1] = {
+static const unsigned char keyrings_capabilities[2] = {
[0] = (KEYCTL_CAPS0_CAPABILITIES |
(IS_ENABLED(CONFIG_PERSISTENT_KEYRINGS) ? KEYCTL_CAPS0_PERSISTENT_KEYRINGS : 0) |
(IS_ENABLED(CONFIG_KEY_DH_OPERATIONS) ? KEYCTL_CAPS0_DIFFIE_HELLMAN : 0) |
@@ -36,6 +36,8 @@ static const unsigned char keyrings_capabilities[1] = {
KEYCTL_CAPS0_RESTRICT_KEYRING |
KEYCTL_CAPS0_MOVE
),
+ [1] = (KEYCTL_CAPS1_NS_KEYRING_NAME |
+ KEYCTL_CAPS1_NS_KEY_TAG),
};
static int key_get_type_from_user(char *type,
@@ -218,7 +220,7 @@ SYSCALL_DEFINE4(request_key, const char __user *, _type,
}
/* do the search */
- key = request_key_and_link(ktype, description, callout_info,
+ key = request_key_and_link(ktype, description, NULL, callout_info,
callout_len, NULL, key_ref_to_ptr(dest_ref),
KEY_ALLOC_IN_QUOTA);
if (IS_ERR(key)) {
@@ -758,7 +760,7 @@ long keyctl_keyring_search(key_serial_t ringid,
}
/* do the search */
- key_ref = keyring_search(keyring_ref, ktype, description);
+ key_ref = keyring_search(keyring_ref, ktype, description, true);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index e4de4070c754..febf36c6ddc5 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -12,10 +12,13 @@
#include <linux/security.h>
#include <linux/seq_file.h>
#include <linux/err.h>
+#include <linux/user_namespace.h>
+#include <linux/nsproxy.h>
#include <keys/keyring-type.h>
#include <keys/user-type.h>
#include <linux/assoc_array_priv.h>
#include <linux/uaccess.h>
+#include <net/net_namespace.h>
#include "internal.h"
/*
@@ -25,11 +28,6 @@
#define KEYRING_SEARCH_MAX_DEPTH 6
/*
- * We keep all named keyrings in a hash to speed looking them up.
- */
-#define KEYRING_NAME_HASH_SIZE (1 << 5)
-
-/*
* We mark pointers we pass to the associative array with bit 1 set if
* they're keyrings and clear otherwise.
*/
@@ -51,17 +49,21 @@ static inline void *keyring_key_to_ptr(struct key *key)
return key;
}
-static struct list_head keyring_name_hash[KEYRING_NAME_HASH_SIZE];
static DEFINE_RWLOCK(keyring_name_lock);
-static inline unsigned keyring_hash(const char *desc)
+/*
+ * Clean up the bits of user_namespace that belong to us.
+ */
+void key_free_user_ns(struct user_namespace *ns)
{
- unsigned bucket = 0;
-
- for (; *desc; desc++)
- bucket += (unsigned char)*desc;
-
- return bucket & (KEYRING_NAME_HASH_SIZE - 1);
+ write_lock(&keyring_name_lock);
+ list_del_init(&ns->keyring_name_list);
+ write_unlock(&keyring_name_lock);
+
+ key_put(ns->user_keyring_register);
+#ifdef CONFIG_PERSISTENT_KEYRINGS
+ key_put(ns->persistent_keyring_register);
+#endif
}
/*
@@ -100,23 +102,17 @@ static DEFINE_MUTEX(keyring_serialise_link_lock);
/*
* Publish the name of a keyring so that it can be found by name (if it has
- * one).
+ * one and it doesn't begin with a dot).
*/
static void keyring_publish_name(struct key *keyring)
{
- int bucket;
-
- if (keyring->description) {
- bucket = keyring_hash(keyring->description);
+ struct user_namespace *ns = current_user_ns();
+ if (keyring->description &&
+ keyring->description[0] &&
+ keyring->description[0] != '.') {
write_lock(&keyring_name_lock);
-
- if (!keyring_name_hash[bucket].next)
- INIT_LIST_HEAD(&keyring_name_hash[bucket]);
-
- list_add_tail(&keyring->name_link,
- &keyring_name_hash[bucket]);
-
+ list_add_tail(&keyring->name_link, &ns->keyring_name_list);
write_unlock(&keyring_name_lock);
}
}
@@ -164,7 +160,7 @@ static u64 mult_64x32_and_fold(u64 x, u32 y)
/*
* Hash a key type and description.
*/
-static unsigned long hash_key_type_and_desc(const struct keyring_index_key *index_key)
+static void hash_key_type_and_desc(struct keyring_index_key *index_key)
{
const unsigned level_shift = ASSOC_ARRAY_LEVEL_STEP;
const unsigned long fan_mask = ASSOC_ARRAY_FAN_MASK;
@@ -175,9 +171,12 @@ static unsigned long hash_key_type_and_desc(const struct keyring_index_key *inde
int n, desc_len = index_key->desc_len;
type = (unsigned long)index_key->type;
-
acc = mult_64x32_and_fold(type, desc_len + 13);
acc = mult_64x32_and_fold(acc, 9207);
+ piece = (unsigned long)index_key->domain_tag;
+ acc = mult_64x32_and_fold(acc, piece);
+ acc = mult_64x32_and_fold(acc, 9207);
+
for (;;) {
n = desc_len;
if (n <= 0)
@@ -202,24 +201,67 @@ static unsigned long hash_key_type_and_desc(const struct keyring_index_key *inde
* zero for keyrings and non-zero otherwise.
*/
if (index_key->type != &key_type_keyring && (hash & fan_mask) == 0)
- return hash | (hash >> (ASSOC_ARRAY_KEY_CHUNK_SIZE - level_shift)) | 1;
- if (index_key->type == &key_type_keyring && (hash & fan_mask) != 0)
- return (hash + (hash << level_shift)) & ~fan_mask;
- return hash;
+ hash |= (hash >> (ASSOC_ARRAY_KEY_CHUNK_SIZE - level_shift)) | 1;
+ else if (index_key->type == &key_type_keyring && (hash & fan_mask) != 0)
+ hash = (hash + (hash << level_shift)) & ~fan_mask;
+ index_key->hash = hash;
}
/*
- * Build the next index key chunk.
- *
- * On 32-bit systems the index key is laid out as:
- *
- * 0 4 5 9...
- * hash desclen typeptr desc[]
+ * Finalise an index key to include a part of the description actually in the
+ * index key, to set the domain tag and to calculate the hash.
+ */
+void key_set_index_key(struct keyring_index_key *index_key)
+{
+ static struct key_tag default_domain_tag = { .usage = REFCOUNT_INIT(1), };
+ size_t n = min_t(size_t, index_key->desc_len, sizeof(index_key->desc));
+
+ memcpy(index_key->desc, index_key->description, n);
+
+ if (!index_key->domain_tag) {
+ if (index_key->type->flags & KEY_TYPE_NET_DOMAIN)
+ index_key->domain_tag = current->nsproxy->net_ns->key_domain;
+ else
+ index_key->domain_tag = &default_domain_tag;
+ }
+
+ hash_key_type_and_desc(index_key);
+}
+
+/**
+ * key_put_tag - Release a ref on a tag.
+ * @tag: The tag to release.
*
- * On 64-bit systems:
+ * This releases a reference the given tag and returns true if that ref was the
+ * last one.
+ */
+bool key_put_tag(struct key_tag *tag)
+{
+ if (refcount_dec_and_test(&tag->usage)) {
+ kfree_rcu(tag, rcu);
+ return true;
+ }
+
+ return false;
+}
+
+/**
+ * key_remove_domain - Kill off a key domain and gc its keys
+ * @domain_tag: The domain tag to release.
*
- * 0 8 9 17...
- * hash desclen typeptr desc[]
+ * This marks a domain tag as being dead and releases a ref on it. If that
+ * wasn't the last reference, the garbage collector is poked to try and delete
+ * all keys that were in the domain.
+ */
+void key_remove_domain(struct key_tag *domain_tag)
+{
+ domain_tag->removed = true;
+ if (!key_put_tag(domain_tag))
+ key_schedule_gc_links();
+}
+
+/*
+ * Build the next index key chunk.
*
* We return it one word-sized chunk at a time.
*/
@@ -227,41 +269,33 @@ static unsigned long keyring_get_key_chunk(const void *data, int level)
{
const struct keyring_index_key *index_key = data;
unsigned long chunk = 0;
- long offset = 0;
+ const u8 *d;
int desc_len = index_key->desc_len, n = sizeof(chunk);
level /= ASSOC_ARRAY_KEY_CHUNK_SIZE;
switch (level) {
case 0:
- return hash_key_type_and_desc(index_key);
+ return index_key->hash;
case 1:
- return ((unsigned long)index_key->type << 8) | desc_len;
+ return index_key->x;
case 2:
- if (desc_len == 0)
- return (u8)((unsigned long)index_key->type >>
- (ASSOC_ARRAY_KEY_CHUNK_SIZE - 8));
- n--;
- offset = 1;
- /* fall through */
+ return (unsigned long)index_key->type;
+ case 3:
+ return (unsigned long)index_key->domain_tag;
default:
- offset += sizeof(chunk) - 1;
- offset += (level - 3) * sizeof(chunk);
- if (offset >= desc_len)
+ level -= 4;
+ if (desc_len <= sizeof(index_key->desc))
return 0;
- desc_len -= offset;
+
+ d = index_key->description + sizeof(index_key->desc);
+ d += level * sizeof(long);
+ desc_len -= sizeof(index_key->desc);
if (desc_len > n)
desc_len = n;
- offset += desc_len;
do {
chunk <<= 8;
- chunk |= ((u8*)index_key->description)[--offset];
+ chunk |= *d++;
} while (--desc_len > 0);
-
- if (level == 2) {
- chunk <<= 8;
- chunk |= (u8)((unsigned long)index_key->type >>
- (ASSOC_ARRAY_KEY_CHUNK_SIZE - 8));
- }
return chunk;
}
}
@@ -278,6 +312,7 @@ static bool keyring_compare_object(const void *object, const void *data)
const struct key *key = keyring_ptr_to_key(object);
return key->index_key.type == index_key->type &&
+ key->index_key.domain_tag == index_key->domain_tag &&
key->index_key.desc_len == index_key->desc_len &&
memcmp(key->index_key.description, index_key->description,
index_key->desc_len) == 0;
@@ -296,43 +331,38 @@ static int keyring_diff_objects(const void *object, const void *data)
int level, i;
level = 0;
- seg_a = hash_key_type_and_desc(a);
- seg_b = hash_key_type_and_desc(b);
+ seg_a = a->hash;
+ seg_b = b->hash;
if ((seg_a ^ seg_b) != 0)
goto differ;
+ level += ASSOC_ARRAY_KEY_CHUNK_SIZE / 8;
/* The number of bits contributed by the hash is controlled by a
* constant in the assoc_array headers. Everything else thereafter we
* can deal with as being machine word-size dependent.
*/
- level += ASSOC_ARRAY_KEY_CHUNK_SIZE / 8;
- seg_a = a->desc_len;
- seg_b = b->desc_len;
+ seg_a = a->x;
+ seg_b = b->x;
if ((seg_a ^ seg_b) != 0)
goto differ;
+ level += sizeof(unsigned long);
/* The next bit may not work on big endian */
- level++;
seg_a = (unsigned long)a->type;
seg_b = (unsigned long)b->type;
if ((seg_a ^ seg_b) != 0)
goto differ;
+ level += sizeof(unsigned long);
+ seg_a = (unsigned long)a->domain_tag;
+ seg_b = (unsigned long)b->domain_tag;
+ if ((seg_a ^ seg_b) != 0)
+ goto differ;
level += sizeof(unsigned long);
- if (a->desc_len == 0)
- goto same;
- i = 0;
- if (((unsigned long)a->description | (unsigned long)b->description) &
- (sizeof(unsigned long) - 1)) {
- do {
- seg_a = *(unsigned long *)(a->description + i);
- seg_b = *(unsigned long *)(b->description + i);
- if ((seg_a ^ seg_b) != 0)
- goto differ_plus_i;
- i += sizeof(unsigned long);
- } while (i < (a->desc_len & (sizeof(unsigned long) - 1)));
- }
+ i = sizeof(a->desc);
+ if (a->desc_len <= i)
+ goto same;
for (; i < a->desc_len; i++) {
seg_a = *(unsigned char *)(a->description + i);
@@ -658,6 +688,9 @@ static bool search_nested_keyrings(struct key *keyring,
BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
(ctx->flags & STATE_CHECKS) == STATE_CHECKS);
+ if (ctx->index_key.description)
+ key_set_index_key(&ctx->index_key);
+
/* Check to see if this top-level keyring is what we are looking for
* and whether it is valid or not.
*/
@@ -697,6 +730,9 @@ descend_to_keyring:
* Non-keyrings avoid the leftmost branch of the root entirely (root
* slots 1-15).
*/
+ if (!(ctx->flags & KEYRING_SEARCH_RECURSE))
+ goto not_this_keyring;
+
ptr = READ_ONCE(keyring->keys.root);
if (!ptr)
goto not_this_keyring;
@@ -897,13 +933,15 @@ key_ref_t keyring_search_rcu(key_ref_t keyring_ref,
* @keyring: The root of the keyring tree to be searched.
* @type: The type of keyring we want to find.
* @description: The name of the keyring we want to find.
+ * @recurse: True to search the children of @keyring also
*
* As keyring_search_rcu() above, but using the current task's credentials and
* type's default matching function and preferred search method.
*/
key_ref_t keyring_search(key_ref_t keyring,
struct key_type *type,
- const char *description)
+ const char *description,
+ bool recurse)
{
struct keyring_search_context ctx = {
.index_key.type = type,
@@ -918,6 +956,8 @@ key_ref_t keyring_search(key_ref_t keyring,
key_ref_t key;
int ret;
+ if (recurse)
+ ctx.flags |= KEYRING_SEARCH_RECURSE;
if (type->match_preparse) {
ret = type->match_preparse(&ctx.match_data);
if (ret < 0)
@@ -1102,50 +1142,44 @@ found:
*/
struct key *find_keyring_by_name(const char *name, bool uid_keyring)
{
+ struct user_namespace *ns = current_user_ns();
struct key *keyring;
- int bucket;
if (!name)
return ERR_PTR(-EINVAL);
- bucket = keyring_hash(name);
-
read_lock(&keyring_name_lock);
- if (keyring_name_hash[bucket].next) {
- /* search this hash bucket for a keyring with a matching name
- * that's readable and that hasn't been revoked */
- list_for_each_entry(keyring,
- &keyring_name_hash[bucket],
- name_link
- ) {
- if (!kuid_has_mapping(current_user_ns(), keyring->user->uid))
- continue;
-
- if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
- continue;
+ /* Search this hash bucket for a keyring with a matching name that
+ * grants Search permission and that hasn't been revoked
+ */
+ list_for_each_entry(keyring, &ns->keyring_name_list, name_link) {
+ if (!kuid_has_mapping(ns, keyring->user->uid))
+ continue;
- if (strcmp(keyring->description, name) != 0)
- continue;
+ if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+ continue;
- if (uid_keyring) {
- if (!test_bit(KEY_FLAG_UID_KEYRING,
- &keyring->flags))
- continue;
- } else {
- if (key_permission(make_key_ref(keyring, 0),
- KEY_NEED_SEARCH) < 0)
- continue;
- }
+ if (strcmp(keyring->description, name) != 0)
+ continue;
- /* we've got a match but we might end up racing with
- * key_cleanup() if the keyring is currently 'dead'
- * (ie. it has a zero usage count) */
- if (!refcount_inc_not_zero(&keyring->usage))
+ if (uid_keyring) {
+ if (!test_bit(KEY_FLAG_UID_KEYRING,
+ &keyring->flags))
+ continue;
+ } else {
+ if (key_permission(make_key_ref(keyring, 0),
+ KEY_NEED_SEARCH) < 0)
continue;
- keyring->last_used_at = ktime_get_real_seconds();
- goto out;
}
+
+ /* we've got a match but we might end up racing with
+ * key_cleanup() if the keyring is currently 'dead'
+ * (ie. it has a zero usage count) */
+ if (!refcount_inc_not_zero(&keyring->usage))
+ continue;
+ keyring->last_used_at = ktime_get_real_seconds();
+ goto out;
}
keyring = ERR_PTR(-ENOKEY);
@@ -1188,7 +1222,8 @@ static int keyring_detect_cycle(struct key *A, struct key *B)
.flags = (KEYRING_SEARCH_NO_STATE_CHECK |
KEYRING_SEARCH_NO_UPDATE_TIME |
KEYRING_SEARCH_NO_CHECK_PERM |
- KEYRING_SEARCH_DETECT_TOO_DEEP),
+ KEYRING_SEARCH_DETECT_TOO_DEEP |
+ KEYRING_SEARCH_RECURSE),
};
rcu_read_lock();
diff --git a/security/keys/persistent.c b/security/keys/persistent.c
index da9a0f42b795..97af230aa4b2 100644
--- a/security/keys/persistent.c
+++ b/security/keys/persistent.c
@@ -80,15 +80,17 @@ static long key_get_persistent(struct user_namespace *ns, kuid_t uid,
long ret;
/* Look in the register if it exists */
+ memset(&index_key, 0, sizeof(index_key));
index_key.type = &key_type_keyring;
index_key.description = buf;
index_key.desc_len = sprintf(buf, "_persistent.%u", from_kuid(ns, uid));
+ key_set_index_key(&index_key);
if (ns->persistent_keyring_register) {
reg_ref = make_key_ref(ns->persistent_keyring_register, true);
- down_read(&ns->persistent_keyring_register_sem);
+ down_read(&ns->keyring_sem);
persistent_ref = find_key_to_update(reg_ref, &index_key);
- up_read(&ns->persistent_keyring_register_sem);
+ up_read(&ns->keyring_sem);
if (persistent_ref)
goto found;
@@ -97,9 +99,9 @@ static long key_get_persistent(struct user_namespace *ns, kuid_t uid,
/* It wasn't in the register, so we'll need to create it. We might
* also need to create the register.
*/
- down_write(&ns->persistent_keyring_register_sem);
+ down_write(&ns->keyring_sem);
persistent_ref = key_create_persistent(ns, uid, &index_key);
- up_write(&ns->persistent_keyring_register_sem);
+ up_write(&ns->keyring_sem);
if (!IS_ERR(persistent_ref))
goto found;
diff --git a/security/keys/proc.c b/security/keys/proc.c
index 7f15550c10f5..415f3f1c2da0 100644
--- a/security/keys/proc.c
+++ b/security/keys/proc.c
@@ -166,7 +166,8 @@ static int proc_keys_show(struct seq_file *m, void *v)
.match_data.cmp = lookup_user_key_possessed,
.match_data.raw_data = key,
.match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
- .flags = KEYRING_SEARCH_NO_STATE_CHECK,
+ .flags = (KEYRING_SEARCH_NO_STATE_CHECK |
+ KEYRING_SEARCH_RECURSE),
};
key_ref = make_key_ref(key, 0);
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index b99ad2c5342f..09541de31f2f 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -15,15 +15,13 @@
#include <linux/security.h>
#include <linux/user_namespace.h>
#include <linux/uaccess.h>
+#include <linux/init_task.h>
#include <keys/request_key_auth-type.h>
#include "internal.h"
/* Session keyring create vs join semaphore */
static DEFINE_MUTEX(key_session_mutex);
-/* User keyring creation semaphore */
-static DEFINE_MUTEX(key_user_keyring_mutex);
-
/* The root user's tracking struct */
struct key_user root_key_user = {
.usage = REFCOUNT_INIT(3),
@@ -35,99 +33,186 @@ struct key_user root_key_user = {
};
/*
- * Install the user and user session keyrings for the current process's UID.
+ * Get or create a user register keyring.
+ */
+static struct key *get_user_register(struct user_namespace *user_ns)
+{
+ struct key *reg_keyring = READ_ONCE(user_ns->user_keyring_register);
+
+ if (reg_keyring)
+ return reg_keyring;
+
+ down_write(&user_ns->keyring_sem);
+
+ /* Make sure there's a register keyring. It gets owned by the
+ * user_namespace's owner.
+ */
+ reg_keyring = user_ns->user_keyring_register;
+ if (!reg_keyring) {
+ reg_keyring = keyring_alloc(".user_reg",
+ user_ns->owner, INVALID_GID,
+ &init_cred,
+ KEY_POS_WRITE | KEY_POS_SEARCH |
+ KEY_USR_VIEW | KEY_USR_READ,
+ 0,
+ NULL, NULL);
+ if (!IS_ERR(reg_keyring))
+ smp_store_release(&user_ns->user_keyring_register,
+ reg_keyring);
+ }
+
+ up_write(&user_ns->keyring_sem);
+
+ /* We don't return a ref since the keyring is pinned by the user_ns */
+ return reg_keyring;
+}
+
+/*
+ * Look up the user and user session keyrings for the current process's UID,
+ * creating them if they don't exist.
*/
-int install_user_keyrings(void)
+int look_up_user_keyrings(struct key **_user_keyring,
+ struct key **_user_session_keyring)
{
- struct user_struct *user;
- const struct cred *cred;
- struct key *uid_keyring, *session_keyring;
+ const struct cred *cred = current_cred();
+ struct user_namespace *user_ns = current_user_ns();
+ struct key *reg_keyring, *uid_keyring, *session_keyring;
key_perm_t user_keyring_perm;
+ key_ref_t uid_keyring_r, session_keyring_r;
+ uid_t uid = from_kuid(user_ns, cred->user->uid);
char buf[20];
int ret;
- uid_t uid;
user_keyring_perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL;
- cred = current_cred();
- user = cred->user;
- uid = from_kuid(cred->user_ns, user->uid);
- kenter("%p{%u}", user, uid);
+ kenter("%u", uid);
- if (READ_ONCE(user->uid_keyring) && READ_ONCE(user->session_keyring)) {
- kleave(" = 0 [exist]");
- return 0;
- }
+ reg_keyring = get_user_register(user_ns);
+ if (IS_ERR(reg_keyring))
+ return PTR_ERR(reg_keyring);
- mutex_lock(&key_user_keyring_mutex);
+ down_write(&user_ns->keyring_sem);
ret = 0;
- if (!user->uid_keyring) {
- /* get the UID-specific keyring
- * - there may be one in existence already as it may have been
- * pinned by a session, but the user_struct pointing to it
- * may have been destroyed by setuid */
- sprintf(buf, "_uid.%u", uid);
-
- uid_keyring = find_keyring_by_name(buf, true);
+ /* Get the user keyring. Note that there may be one in existence
+ * already as it may have been pinned by a session, but the user_struct
+ * pointing to it may have been destroyed by setuid.
+ */
+ snprintf(buf, sizeof(buf), "_uid.%u", uid);
+ uid_keyring_r = keyring_search(make_key_ref(reg_keyring, true),
+ &key_type_keyring, buf, false);
+ kdebug("_uid %p", uid_keyring_r);
+ if (uid_keyring_r == ERR_PTR(-EAGAIN)) {
+ uid_keyring = keyring_alloc(buf, cred->user->uid, INVALID_GID,
+ cred, user_keyring_perm,
+ KEY_ALLOC_UID_KEYRING |
+ KEY_ALLOC_IN_QUOTA,
+ NULL, reg_keyring);
if (IS_ERR(uid_keyring)) {
- uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID,
- cred, user_keyring_perm,
- KEY_ALLOC_UID_KEYRING |
- KEY_ALLOC_IN_QUOTA,
- NULL, NULL);
- if (IS_ERR(uid_keyring)) {
- ret = PTR_ERR(uid_keyring);
- goto error;
- }
+ ret = PTR_ERR(uid_keyring);
+ goto error;
}
+ } else if (IS_ERR(uid_keyring_r)) {
+ ret = PTR_ERR(uid_keyring_r);
+ goto error;
+ } else {
+ uid_keyring = key_ref_to_ptr(uid_keyring_r);
+ }
- /* get a default session keyring (which might also exist
- * already) */
- sprintf(buf, "_uid_ses.%u", uid);
-
- session_keyring = find_keyring_by_name(buf, true);
+ /* Get a default session keyring (which might also exist already) */
+ snprintf(buf, sizeof(buf), "_uid_ses.%u", uid);
+ session_keyring_r = keyring_search(make_key_ref(reg_keyring, true),
+ &key_type_keyring, buf, false);
+ kdebug("_uid_ses %p", session_keyring_r);
+ if (session_keyring_r == ERR_PTR(-EAGAIN)) {
+ session_keyring = keyring_alloc(buf, cred->user->uid, INVALID_GID,
+ cred, user_keyring_perm,
+ KEY_ALLOC_UID_KEYRING |
+ KEY_ALLOC_IN_QUOTA,
+ NULL, NULL);
if (IS_ERR(session_keyring)) {
- session_keyring =
- keyring_alloc(buf, user->uid, INVALID_GID,
- cred, user_keyring_perm,
- KEY_ALLOC_UID_KEYRING |
- KEY_ALLOC_IN_QUOTA,
- NULL, NULL);
- if (IS_ERR(session_keyring)) {
- ret = PTR_ERR(session_keyring);
- goto error_release;
- }
-
- /* we install a link from the user session keyring to
- * the user keyring */
- ret = key_link(session_keyring, uid_keyring);
- if (ret < 0)
- goto error_release_both;
+ ret = PTR_ERR(session_keyring);
+ goto error_release;
}
- /* install the keyrings */
- /* paired with READ_ONCE() */
- smp_store_release(&user->uid_keyring, uid_keyring);
- /* paired with READ_ONCE() */
- smp_store_release(&user->session_keyring, session_keyring);
+ /* We install a link from the user session keyring to
+ * the user keyring.
+ */
+ ret = key_link(session_keyring, uid_keyring);
+ if (ret < 0)
+ goto error_release_session;
+
+ /* And only then link the user-session keyring to the
+ * register.
+ */
+ ret = key_link(reg_keyring, session_keyring);
+ if (ret < 0)
+ goto error_release_session;
+ } else if (IS_ERR(session_keyring_r)) {
+ ret = PTR_ERR(session_keyring_r);
+ goto error_release;
+ } else {
+ session_keyring = key_ref_to_ptr(session_keyring_r);
}
- mutex_unlock(&key_user_keyring_mutex);
+ up_write(&user_ns->keyring_sem);
+
+ if (_user_session_keyring)
+ *_user_session_keyring = session_keyring;
+ else
+ key_put(session_keyring);
+ if (_user_keyring)
+ *_user_keyring = uid_keyring;
+ else
+ key_put(uid_keyring);
kleave(" = 0");
return 0;
-error_release_both:
+error_release_session:
key_put(session_keyring);
error_release:
key_put(uid_keyring);
error:
- mutex_unlock(&key_user_keyring_mutex);
+ up_write(&user_ns->keyring_sem);
kleave(" = %d", ret);
return ret;
}
/*
+ * Get the user session keyring if it exists, but don't create it if it
+ * doesn't.
+ */
+struct key *get_user_session_keyring_rcu(const struct cred *cred)
+{
+ struct key *reg_keyring = READ_ONCE(cred->user_ns->user_keyring_register);
+ key_ref_t session_keyring_r;
+ char buf[20];
+
+ struct keyring_search_context ctx = {
+ .index_key.type = &key_type_keyring,
+ .index_key.description = buf,
+ .cred = cred,
+ .match_data.cmp = key_default_cmp,
+ .match_data.raw_data = buf,
+ .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
+ .flags = KEYRING_SEARCH_DO_STATE_CHECK,
+ };
+
+ if (!reg_keyring)
+ return NULL;
+
+ ctx.index_key.desc_len = snprintf(buf, sizeof(buf), "_uid_ses.%u",
+ from_kuid(cred->user_ns,
+ cred->user->uid));
+
+ session_keyring_r = keyring_search_rcu(make_key_ref(reg_keyring, true),
+ &ctx);
+ if (IS_ERR(session_keyring_r))
+ return NULL;
+ return key_ref_to_ptr(session_keyring_r);
+}
+
+/*
* Install a thread keyring to the given credentials struct if it didn't have
* one already. This is allowed to overrun the quota.
*
@@ -336,6 +421,7 @@ void key_fsgid_changed(struct cred *new_cred)
*/
key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx)
{
+ struct key *user_session;
key_ref_t key_ref, ret, err;
const struct cred *cred = ctx->cred;
@@ -411,10 +497,11 @@ key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx)
}
}
/* or search the user-session keyring */
- else if (READ_ONCE(cred->user->session_keyring)) {
- key_ref = keyring_search_rcu(
- make_key_ref(READ_ONCE(cred->user->session_keyring), 1),
- ctx);
+ else if ((user_session = get_user_session_keyring_rcu(cred))) {
+ key_ref = keyring_search_rcu(make_key_ref(user_session, 1),
+ ctx);
+ key_put(user_session);
+
if (!IS_ERR(key_ref))
goto found;
@@ -527,10 +614,11 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
struct keyring_search_context ctx = {
.match_data.cmp = lookup_user_key_possessed,
.match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
- .flags = KEYRING_SEARCH_NO_STATE_CHECK,
+ .flags = (KEYRING_SEARCH_NO_STATE_CHECK |
+ KEYRING_SEARCH_RECURSE),
};
struct request_key_auth *rka;
- struct key *key;
+ struct key *key, *user_session;
key_ref_t key_ref, skey_ref;
int ret;
@@ -579,20 +667,20 @@ try_again:
if (!ctx.cred->session_keyring) {
/* always install a session keyring upon access if one
* doesn't exist yet */
- ret = install_user_keyrings();
+ ret = look_up_user_keyrings(NULL, &user_session);
if (ret < 0)
goto error;
if (lflags & KEY_LOOKUP_CREATE)
ret = join_session_keyring(NULL);
else
- ret = install_session_keyring(
- ctx.cred->user->session_keyring);
+ ret = install_session_keyring(user_session);
+ key_put(user_session);
if (ret < 0)
goto error;
goto reget_creds;
- } else if (ctx.cred->session_keyring ==
- READ_ONCE(ctx.cred->user->session_keyring) &&
+ } else if (test_bit(KEY_FLAG_UID_KEYRING,
+ &ctx.cred->session_keyring->flags) &&
lflags & KEY_LOOKUP_CREATE) {
ret = join_session_keyring(NULL);
if (ret < 0)
@@ -606,26 +694,16 @@ try_again:
break;
case KEY_SPEC_USER_KEYRING:
- if (!READ_ONCE(ctx.cred->user->uid_keyring)) {
- ret = install_user_keyrings();
- if (ret < 0)
- goto error;
- }
-
- key = ctx.cred->user->uid_keyring;
- __key_get(key);
+ ret = look_up_user_keyrings(&key, NULL);
+ if (ret < 0)
+ goto error;
key_ref = make_key_ref(key, 1);
break;
case KEY_SPEC_USER_SESSION_KEYRING:
- if (!READ_ONCE(ctx.cred->user->session_keyring)) {
- ret = install_user_keyrings();
- if (ret < 0)
- goto error;
- }
-
- key = ctx.cred->user->session_keyring;
- __key_get(key);
+ ret = look_up_user_keyrings(NULL, &key);
+ if (ret < 0)
+ goto error;
key_ref = make_key_ref(key, 1);
break;
@@ -874,7 +952,7 @@ void key_change_session_keyring(struct callback_head *twork)
*/
static int __init init_root_keyring(void)
{
- return install_user_keyrings();
+ return look_up_user_keyrings(NULL, NULL);
}
late_initcall(init_root_keyring);
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index f2b4da143963..7325f382dbf4 100644
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -13,6 +13,7 @@
#include <linux/err.h>
#include <linux/keyctl.h>
#include <linux/slab.h>
+#include <net/net_namespace.h>
#include "internal.h"
#include <keys/request_key_auth-type.h>
@@ -117,7 +118,7 @@ static int call_sbin_request_key(struct key *authkey, void *aux)
struct request_key_auth *rka = get_request_key_auth(authkey);
const struct cred *cred = current_cred();
key_serial_t prkey, sskey;
- struct key *key = rka->target_key, *keyring, *session;
+ struct key *key = rka->target_key, *keyring, *session, *user_session;
char *argv[9], *envp[3], uid_str[12], gid_str[12];
char key_str[12], keyring_str[3][12];
char desc[20];
@@ -125,9 +126,9 @@ static int call_sbin_request_key(struct key *authkey, void *aux)
kenter("{%d},{%d},%s", key->serial, authkey->serial, rka->op);
- ret = install_user_keyrings();
+ ret = look_up_user_keyrings(NULL, &user_session);
if (ret < 0)
- goto error_alloc;
+ goto error_us;
/* allocate a new session keyring */
sprintf(desc, "_req.%u", key->serial);
@@ -165,7 +166,7 @@ static int call_sbin_request_key(struct key *authkey, void *aux)
session = cred->session_keyring;
if (!session)
- session = cred->user->session_keyring;
+ session = user_session;
sskey = session->serial;
sprintf(keyring_str[2], "%d", sskey);
@@ -207,6 +208,8 @@ error_link:
key_put(keyring);
error_alloc:
+ key_put(user_session);
+error_us:
complete_request_key(authkey, ret);
kleave(" = %d", ret);
return ret;
@@ -313,13 +316,15 @@ static int construct_get_dest_keyring(struct key **_dest_keyring)
/* fall through */
case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
- dest_keyring =
- key_get(READ_ONCE(cred->user->session_keyring));
+ ret = look_up_user_keyrings(NULL, &dest_keyring);
+ if (ret < 0)
+ return ret;
break;
case KEY_REQKEY_DEFL_USER_KEYRING:
- dest_keyring =
- key_get(READ_ONCE(cred->user->uid_keyring));
+ ret = look_up_user_keyrings(&dest_keyring, NULL);
+ if (ret < 0)
+ return ret;
break;
case KEY_REQKEY_DEFL_GROUP_KEYRING:
@@ -525,16 +530,18 @@ error:
* request_key_and_link - Request a key and cache it in a keyring.
* @type: The type of key we want.
* @description: The searchable description of the key.
+ * @domain_tag: The domain in which the key operates.
* @callout_info: The data to pass to the instantiation upcall (or NULL).
* @callout_len: The length of callout_info.
* @aux: Auxiliary data for the upcall.
* @dest_keyring: Where to cache the key.
* @flags: Flags to key_alloc().
*
- * A key matching the specified criteria is searched for in the process's
- * keyrings and returned with its usage count incremented if found. Otherwise,
- * if callout_info is not NULL, a key will be allocated and some service
- * (probably in userspace) will be asked to instantiate it.
+ * A key matching the specified criteria (type, description, domain_tag) is
+ * searched for in the process's keyrings and returned with its usage count
+ * incremented if found. Otherwise, if callout_info is not NULL, a key will be
+ * allocated and some service (probably in userspace) will be asked to
+ * instantiate it.
*
* If successfully found or created, the key will be linked to the destination
* keyring if one is provided.
@@ -550,6 +557,7 @@ error:
*/
struct key *request_key_and_link(struct key_type *type,
const char *description,
+ struct key_tag *domain_tag,
const void *callout_info,
size_t callout_len,
void *aux,
@@ -558,6 +566,7 @@ struct key *request_key_and_link(struct key_type *type,
{
struct keyring_search_context ctx = {
.index_key.type = type,
+ .index_key.domain_tag = domain_tag,
.index_key.description = description,
.index_key.desc_len = strlen(description),
.cred = current_cred(),
@@ -565,7 +574,8 @@ struct key *request_key_and_link(struct key_type *type,
.match_data.raw_data = description,
.match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
.flags = (KEYRING_SEARCH_DO_STATE_CHECK |
- KEYRING_SEARCH_SKIP_EXPIRED),
+ KEYRING_SEARCH_SKIP_EXPIRED |
+ KEYRING_SEARCH_RECURSE),
};
struct key *key;
key_ref_t key_ref;
@@ -663,9 +673,10 @@ int wait_for_key_construction(struct key *key, bool intr)
EXPORT_SYMBOL(wait_for_key_construction);
/**
- * request_key - Request a key and wait for construction
+ * request_key_tag - Request a key and wait for construction
* @type: Type of key.
* @description: The searchable description of the key.
+ * @domain_tag: The domain in which the key operates.
* @callout_info: The data to pass to the instantiation upcall (or NULL).
*
* As for request_key_and_link() except that it does not add the returned key
@@ -676,9 +687,10 @@ EXPORT_SYMBOL(wait_for_key_construction);
* Furthermore, it then works as wait_for_key_construction() to wait for the
* completion of keys undergoing construction with a non-interruptible wait.
*/
-struct key *request_key(struct key_type *type,
- const char *description,
- const char *callout_info)
+struct key *request_key_tag(struct key_type *type,
+ const char *description,
+ struct key_tag *domain_tag,
+ const char *callout_info)
{
struct key *key;
size_t callout_len = 0;
@@ -686,7 +698,8 @@ struct key *request_key(struct key_type *type,
if (callout_info)
callout_len = strlen(callout_info);
- key = request_key_and_link(type, description, callout_info, callout_len,
+ key = request_key_and_link(type, description, domain_tag,
+ callout_info, callout_len,
NULL, NULL, KEY_ALLOC_IN_QUOTA);
if (!IS_ERR(key)) {
ret = wait_for_key_construction(key, false);
@@ -697,12 +710,13 @@ struct key *request_key(struct key_type *type,
}
return key;
}
-EXPORT_SYMBOL(request_key);
+EXPORT_SYMBOL(request_key_tag);
/**
* request_key_with_auxdata - Request a key with auxiliary data for the upcaller
* @type: The type of key we want.
* @description: The searchable description of the key.
+ * @domain_tag: The domain in which the key operates.
* @callout_info: The data to pass to the instantiation upcall (or NULL).
* @callout_len: The length of callout_info.
* @aux: Auxiliary data for the upcall.
@@ -715,6 +729,7 @@ EXPORT_SYMBOL(request_key);
*/
struct key *request_key_with_auxdata(struct key_type *type,
const char *description,
+ struct key_tag *domain_tag,
const void *callout_info,
size_t callout_len,
void *aux)
@@ -722,7 +737,8 @@ struct key *request_key_with_auxdata(struct key_type *type,
struct key *key;
int ret;
- key = request_key_and_link(type, description, callout_info, callout_len,
+ key = request_key_and_link(type, description, domain_tag,
+ callout_info, callout_len,
aux, NULL, KEY_ALLOC_IN_QUOTA);
if (!IS_ERR(key)) {
ret = wait_for_key_construction(key, false);
@@ -739,6 +755,7 @@ EXPORT_SYMBOL(request_key_with_auxdata);
* request_key_rcu - Request key from RCU-read-locked context
* @type: The type of key we want.
* @description: The name of the key we want.
+ * @domain_tag: The domain in which the key operates.
*
* Request a key from a context that we may not sleep in (such as RCU-mode
* pathwalk). Keys under construction are ignored.
@@ -746,10 +763,13 @@ EXPORT_SYMBOL(request_key_with_auxdata);
* Return a pointer to the found key if successful, -ENOKEY if we couldn't find
* a key or some other error if the key found was unsuitable or inaccessible.
*/
-struct key *request_key_rcu(struct key_type *type, const char *description)
+struct key *request_key_rcu(struct key_type *type,
+ const char *description,
+ struct key_tag *domain_tag)
{
struct keyring_search_context ctx = {
.index_key.type = type,
+ .index_key.domain_tag = domain_tag,
.index_key.description = description,
.index_key.desc_len = strlen(description),
.cred = current_cred(),
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index 5456c0c72857..e73ec040e250 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -248,7 +248,8 @@ struct key *key_get_instantiation_authkey(key_serial_t target_id)
.match_data.cmp = key_default_cmp,
.match_data.raw_data = description,
.match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
- .flags = KEYRING_SEARCH_DO_STATE_CHECK,
+ .flags = (KEYRING_SEARCH_DO_STATE_CHECK |
+ KEYRING_SEARCH_RECURSE),
};
struct key *authkey;
key_ref_t authkey_ref;