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-rw-r--r--security/dummy.c16
-rw-r--r--security/inode.c8
-rw-r--r--security/keys/key.c12
-rw-r--r--security/keys/keyring.c5
-rw-r--r--security/keys/process_keys.c57
-rw-r--r--security/keys/request_key.c6
-rw-r--r--security/keys/request_key_auth.c47
-rw-r--r--security/selinux/hooks.c82
-rw-r--r--security/selinux/include/av_perm_to_string.h6
-rw-r--r--security/selinux/include/av_permissions.h8
-rw-r--r--security/selinux/include/class_to_string.h1
-rw-r--r--security/selinux/include/flask.h1
-rw-r--r--security/selinux/include/objsec.h5
-rw-r--r--security/selinux/selinuxfs.c7
14 files changed, 216 insertions, 45 deletions
diff --git a/security/dummy.c b/security/dummy.c
index 64f6da0f422..c3c5493581e 100644
--- a/security/dummy.c
+++ b/security/dummy.c
@@ -191,7 +191,7 @@ static int dummy_sb_kern_mount (struct super_block *sb, void *data)
return 0;
}
-static int dummy_sb_statfs (struct super_block *sb)
+static int dummy_sb_statfs (struct dentry *dentry)
{
return 0;
}
@@ -516,6 +516,11 @@ static int dummy_task_setnice (struct task_struct *p, int nice)
return 0;
}
+static int dummy_task_setioprio (struct task_struct *p, int ioprio)
+{
+ return 0;
+}
+
static int dummy_task_setrlimit (unsigned int resource, struct rlimit *new_rlim)
{
return 0;
@@ -532,6 +537,11 @@ static int dummy_task_getscheduler (struct task_struct *p)
return 0;
}
+static int dummy_task_movememory (struct task_struct *p)
+{
+ return 0;
+}
+
static int dummy_task_wait (struct task_struct *p)
{
return 0;
@@ -860,7 +870,7 @@ static int dummy_setprocattr(struct task_struct *p, char *name, void *value, siz
}
#ifdef CONFIG_KEYS
-static inline int dummy_key_alloc(struct key *key)
+static inline int dummy_key_alloc(struct key *key, struct task_struct *ctx)
{
return 0;
}
@@ -972,9 +982,11 @@ void security_fixup_ops (struct security_operations *ops)
set_to_dummy_if_null(ops, task_getsid);
set_to_dummy_if_null(ops, task_setgroups);
set_to_dummy_if_null(ops, task_setnice);
+ set_to_dummy_if_null(ops, task_setioprio);
set_to_dummy_if_null(ops, task_setrlimit);
set_to_dummy_if_null(ops, task_setscheduler);
set_to_dummy_if_null(ops, task_getscheduler);
+ set_to_dummy_if_null(ops, task_movememory);
set_to_dummy_if_null(ops, task_wait);
set_to_dummy_if_null(ops, task_kill);
set_to_dummy_if_null(ops, task_prctl);
diff --git a/security/inode.c b/security/inode.c
index 8bf40625c67..98a0df500dc 100644
--- a/security/inode.c
+++ b/security/inode.c
@@ -135,11 +135,11 @@ static int fill_super(struct super_block *sb, void *data, int silent)
return simple_fill_super(sb, SECURITYFS_MAGIC, files);
}
-static struct super_block *get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name,
- void *data)
+static int get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name,
+ void *data, struct vfsmount *mnt)
{
- return get_sb_single(fs_type, flags, data, fill_super);
+ return get_sb_single(fs_type, flags, data, fill_super, mnt);
}
static struct file_system_type fs_type = {
diff --git a/security/keys/key.c b/security/keys/key.c
index 3fdc49c6a02..51f85155738 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -247,8 +247,8 @@ static inline void key_alloc_serial(struct key *key)
* instantiate the key or discard it before returning
*/
struct key *key_alloc(struct key_type *type, const char *desc,
- uid_t uid, gid_t gid, key_perm_t perm,
- int not_in_quota)
+ uid_t uid, gid_t gid, struct task_struct *ctx,
+ key_perm_t perm, int not_in_quota)
{
struct key_user *user = NULL;
struct key *key;
@@ -318,7 +318,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
#endif
/* let the security module know about the key */
- ret = security_key_alloc(key);
+ ret = security_key_alloc(key, ctx);
if (ret < 0)
goto security_error;
@@ -822,7 +822,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
/* allocate a new key */
key = key_alloc(ktype, description, current->fsuid, current->fsgid,
- perm, not_in_quota);
+ current, perm, not_in_quota);
if (IS_ERR(key)) {
key_ref = ERR_PTR(PTR_ERR(key));
goto error_3;
@@ -907,6 +907,10 @@ void key_revoke(struct key *key)
* it */
down_write(&key->sem);
set_bit(KEY_FLAG_REVOKED, &key->flags);
+
+ if (key->type->revoke)
+ key->type->revoke(key);
+
up_write(&key->sem);
} /* end key_revoke() */
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index bffa924c1f8..1357207fc9d 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -240,13 +240,14 @@ static long keyring_read(const struct key *keyring,
* allocate a keyring and link into the destination keyring
*/
struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
- int not_in_quota, struct key *dest)
+ struct task_struct *ctx, int not_in_quota,
+ struct key *dest)
{
struct key *keyring;
int ret;
keyring = key_alloc(&key_type_keyring, description,
- uid, gid,
+ uid, gid, ctx,
(KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
not_in_quota);
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 217a0bef3c8..4d9825f9962 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -67,7 +67,8 @@ struct key root_session_keyring = {
/*
* allocate the keyrings to be associated with a UID
*/
-int alloc_uid_keyring(struct user_struct *user)
+int alloc_uid_keyring(struct user_struct *user,
+ struct task_struct *ctx)
{
struct key *uid_keyring, *session_keyring;
char buf[20];
@@ -76,7 +77,7 @@ int alloc_uid_keyring(struct user_struct *user)
/* concoct a default session keyring */
sprintf(buf, "_uid_ses.%u", user->uid);
- session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0, NULL);
+ session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0, NULL);
if (IS_ERR(session_keyring)) {
ret = PTR_ERR(session_keyring);
goto error;
@@ -86,7 +87,7 @@ int alloc_uid_keyring(struct user_struct *user)
* keyring */
sprintf(buf, "_uid.%u", user->uid);
- uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0,
+ uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0,
session_keyring);
if (IS_ERR(uid_keyring)) {
key_put(session_keyring);
@@ -143,7 +144,7 @@ int install_thread_keyring(struct task_struct *tsk)
sprintf(buf, "_tid.%u", tsk->pid);
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+ keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error;
@@ -177,7 +178,7 @@ int install_process_keyring(struct task_struct *tsk)
if (!tsk->signal->process_keyring) {
sprintf(buf, "_pid.%u", tsk->tgid);
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+ keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error;
@@ -217,7 +218,7 @@ static int install_session_keyring(struct task_struct *tsk,
if (!keyring) {
sprintf(buf, "_ses.%u", tsk->tgid);
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+ keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
if (IS_ERR(keyring))
return PTR_ERR(keyring);
}
@@ -390,6 +391,8 @@ key_ref_t search_process_keyrings(struct key_type *type,
struct request_key_auth *rka;
key_ref_t key_ref, ret, err;
+ might_sleep();
+
/* we want to return -EAGAIN or -ENOKEY if any of the keyrings were
* searchable, but we failed to find a key or we found a negative key;
* otherwise we want to return a sample error (probably -EACCES) if
@@ -495,27 +498,35 @@ key_ref_t search_process_keyrings(struct key_type *type,
*/
if (context->request_key_auth &&
context == current &&
- type != &key_type_request_key_auth &&
- key_validate(context->request_key_auth) == 0
+ type != &key_type_request_key_auth
) {
- rka = context->request_key_auth->payload.data;
+ /* defend against the auth key being revoked */
+ down_read(&context->request_key_auth->sem);
- key_ref = search_process_keyrings(type, description, match,
- rka->context);
+ if (key_validate(context->request_key_auth) == 0) {
+ rka = context->request_key_auth->payload.data;
- if (!IS_ERR(key_ref))
- goto found;
+ key_ref = search_process_keyrings(type, description,
+ match, rka->context);
- switch (PTR_ERR(key_ref)) {
- case -EAGAIN: /* no key */
- if (ret)
+ up_read(&context->request_key_auth->sem);
+
+ if (!IS_ERR(key_ref))
+ goto found;
+
+ switch (PTR_ERR(key_ref)) {
+ case -EAGAIN: /* no key */
+ if (ret)
+ break;
+ case -ENOKEY: /* negative key */
+ ret = key_ref;
break;
- case -ENOKEY: /* negative key */
- ret = key_ref;
- break;
- default:
- err = key_ref;
- break;
+ default:
+ err = key_ref;
+ break;
+ }
+ } else {
+ up_read(&context->request_key_auth->sem);
}
}
@@ -717,7 +728,7 @@ long join_session_keyring(const char *name)
keyring = find_keyring_by_name(name, 0);
if (PTR_ERR(keyring) == -ENOKEY) {
/* not found - try and create a new one */
- keyring = keyring_alloc(name, tsk->uid, tsk->gid, 0, NULL);
+ keyring = keyring_alloc(name, tsk->uid, tsk->gid, tsk, 0, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error2;
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index f030a0ccbb9..eab66a06ca5 100644
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -48,7 +48,8 @@ static int call_sbin_request_key(struct key *key,
/* allocate a new session keyring */
sprintf(desc, "_req.%u", key->serial);
- keyring = keyring_alloc(desc, current->fsuid, current->fsgid, 1, NULL);
+ keyring = keyring_alloc(desc, current->fsuid, current->fsgid,
+ current, 1, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error_alloc;
@@ -137,7 +138,8 @@ static struct key *__request_key_construction(struct key_type *type,
/* create a key and add it to the queue */
key = key_alloc(type, description,
- current->fsuid, current->fsgid, KEY_POS_ALL, 0);
+ current->fsuid, current->fsgid,
+ current, KEY_POS_ALL, 0);
if (IS_ERR(key))
goto alloc_failed;
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index cce6ba6b032..cb9817ced3f 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -20,6 +20,7 @@
static int request_key_auth_instantiate(struct key *, const void *, size_t);
static void request_key_auth_describe(const struct key *, struct seq_file *);
+static void request_key_auth_revoke(struct key *);
static void request_key_auth_destroy(struct key *);
static long request_key_auth_read(const struct key *, char __user *, size_t);
@@ -31,6 +32,7 @@ struct key_type key_type_request_key_auth = {
.def_datalen = sizeof(struct request_key_auth),
.instantiate = request_key_auth_instantiate,
.describe = request_key_auth_describe,
+ .revoke = request_key_auth_revoke,
.destroy = request_key_auth_destroy,
.read = request_key_auth_read,
};
@@ -93,6 +95,24 @@ static long request_key_auth_read(const struct key *key,
/*****************************************************************************/
/*
+ * handle revocation of an authorisation token key
+ * - called with the key sem write-locked
+ */
+static void request_key_auth_revoke(struct key *key)
+{
+ struct request_key_auth *rka = key->payload.data;
+
+ kenter("{%d}", key->serial);
+
+ if (rka->context) {
+ put_task_struct(rka->context);
+ rka->context = NULL;
+ }
+
+} /* end request_key_auth_revoke() */
+
+/*****************************************************************************/
+/*
* destroy an instantiation authorisation token key
*/
static void request_key_auth_destroy(struct key *key)
@@ -101,6 +121,11 @@ static void request_key_auth_destroy(struct key *key)
kenter("{%d}", key->serial);
+ if (rka->context) {
+ put_task_struct(rka->context);
+ rka->context = NULL;
+ }
+
key_put(rka->target_key);
kfree(rka);
@@ -131,14 +156,26 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info)
* another process */
if (current->request_key_auth) {
/* it is - use that instantiation context here too */
+ down_read(&current->request_key_auth->sem);
+
+ /* if the auth key has been revoked, then the key we're
+ * servicing is already instantiated */
+ if (test_bit(KEY_FLAG_REVOKED,
+ &current->request_key_auth->flags))
+ goto auth_key_revoked;
+
irka = current->request_key_auth->payload.data;
rka->context = irka->context;
rka->pid = irka->pid;
+ get_task_struct(rka->context);
+
+ up_read(&current->request_key_auth->sem);
}
else {
/* it isn't - use this process as the context */
rka->context = current;
rka->pid = current->pid;
+ get_task_struct(rka->context);
}
rka->target_key = key_get(target);
@@ -148,7 +185,7 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info)
sprintf(desc, "%x", target->serial);
authkey = key_alloc(&key_type_request_key_auth, desc,
- current->fsuid, current->fsgid,
+ current->fsuid, current->fsgid, current,
KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH |
KEY_USR_VIEW, 1);
if (IS_ERR(authkey)) {
@@ -161,9 +198,15 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info)
if (ret < 0)
goto error_inst;
- kleave(" = {%d})", authkey->serial);
+ kleave(" = {%d}", authkey->serial);
return authkey;
+auth_key_revoked:
+ up_read(&current->request_key_auth->sem);
+ kfree(rka);
+ kleave("= -EKEYREVOKED");
+ return ERR_PTR(-EKEYREVOKED);
+
error_inst:
key_revoke(authkey);
key_put(authkey);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 54adc9d31e9..79c16e31c88 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1903,13 +1903,13 @@ static int selinux_sb_kern_mount(struct super_block *sb, void *data)
return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
}
-static int selinux_sb_statfs(struct super_block *sb)
+static int selinux_sb_statfs(struct dentry *dentry)
{
struct avc_audit_data ad;
AVC_AUDIT_DATA_INIT(&ad,FS);
- ad.u.fs.dentry = sb->s_root;
- return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad);
+ ad.u.fs.dentry = dentry->d_sb->s_root;
+ return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
}
static int selinux_mount(char * dev_name,
@@ -2645,6 +2645,11 @@ static int selinux_task_setnice(struct task_struct *p, int nice)
return task_has_perm(current,p, PROCESS__SETSCHED);
}
+static int selinux_task_setioprio(struct task_struct *p, int ioprio)
+{
+ return task_has_perm(current, p, PROCESS__SETSCHED);
+}
+
static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
{
struct rlimit *old_rlim = current->signal->rlim + resource;
@@ -2674,6 +2679,11 @@ static int selinux_task_getscheduler(struct task_struct *p)
return task_has_perm(current, p, PROCESS__GETSCHED);
}
+static int selinux_task_movememory(struct task_struct *p)
+{
+ return task_has_perm(current, p, PROCESS__SETSCHED);
+}
+
static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
{
u32 perm;
@@ -4252,6 +4262,57 @@ static int selinux_setprocattr(struct task_struct *p,
return size;
}
+#ifdef CONFIG_KEYS
+
+static int selinux_key_alloc(struct key *k, struct task_struct *tsk)
+{
+ struct task_security_struct *tsec = tsk->security;
+ struct key_security_struct *ksec;
+
+ ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
+ if (!ksec)
+ return -ENOMEM;
+
+ ksec->obj = k;
+ ksec->sid = tsec->sid;
+ k->security = ksec;
+
+ return 0;
+}
+
+static void selinux_key_free(struct key *k)
+{
+ struct key_security_struct *ksec = k->security;
+
+ k->security = NULL;
+ kfree(ksec);
+}
+
+static int selinux_key_permission(key_ref_t key_ref,
+ struct task_struct *ctx,
+ key_perm_t perm)
+{
+ struct key *key;
+ struct task_security_struct *tsec;
+ struct key_security_struct *ksec;
+
+ key = key_ref_to_ptr(key_ref);
+
+ tsec = ctx->security;
+ ksec = key->security;
+
+ /* if no specific permissions are requested, we skip the
+ permission check. No serious, additional covert channels
+ appear to be created. */
+ if (perm == 0)
+ return 0;
+
+ return avc_has_perm(tsec->sid, ksec->sid,
+ SECCLASS_KEY, perm, NULL);
+}
+
+#endif
+
static struct security_operations selinux_ops = {
.ptrace = selinux_ptrace,
.capget = selinux_capget,
@@ -4332,9 +4393,11 @@ static struct security_operations selinux_ops = {
.task_getsid = selinux_task_getsid,
.task_setgroups = selinux_task_setgroups,
.task_setnice = selinux_task_setnice,
+ .task_setioprio = selinux_task_setioprio,
.task_setrlimit = selinux_task_setrlimit,
.task_setscheduler = selinux_task_setscheduler,
.task_getscheduler = selinux_task_getscheduler,
+ .task_movememory = selinux_task_movememory,
.task_kill = selinux_task_kill,
.task_wait = selinux_task_wait,
.task_prctl = selinux_task_prctl,
@@ -4406,6 +4469,12 @@ static struct security_operations selinux_ops = {
.xfrm_state_delete_security = selinux_xfrm_state_delete,
.xfrm_policy_lookup = selinux_xfrm_policy_lookup,
#endif
+
+#ifdef CONFIG_KEYS
+ .key_alloc = selinux_key_alloc,
+ .key_free = selinux_key_free,
+ .key_permission = selinux_key_permission,
+#endif
};
static __init int selinux_init(void)
@@ -4441,6 +4510,13 @@ static __init int selinux_init(void)
} else {
printk(KERN_INFO "SELinux: Starting in permissive mode\n");
}
+
+#ifdef CONFIG_KEYS
+ /* Add security information to initial keyrings */
+ security_key_alloc(&root_user_keyring, current);
+ security_key_alloc(&root_session_keyring, current);
+#endif
+
return 0;
}
diff --git a/security/selinux/include/av_perm_to_string.h b/security/selinux/include/av_perm_to_string.h
index 70ee65a5881..bc020bde6c8 100644
--- a/security/selinux/include/av_perm_to_string.h
+++ b/security/selinux/include/av_perm_to_string.h
@@ -242,3 +242,9 @@
S_(SECCLASS_PACKET, PACKET__SEND, "send")
S_(SECCLASS_PACKET, PACKET__RECV, "recv")
S_(SECCLASS_PACKET, PACKET__RELABELTO, "relabelto")
+ S_(SECCLASS_KEY, KEY__VIEW, "view")
+ S_(SECCLASS_KEY, KEY__READ, "read")
+ S_(SECCLASS_KEY, KEY__WRITE, "write")
+ S_(SECCLASS_KEY, KEY__SEARCH, "search")
+ S_(SECCLASS_KEY, KEY__LINK, "link")
+ S_(SECCLASS_KEY, KEY__SETATTR, "setattr")
diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h
index 1d9cf3d306b..1205227a3a3 100644
--- a/security/selinux/include/av_permissions.h
+++ b/security/selinux/include/av_permissions.h
@@ -959,3 +959,11 @@
#define PACKET__SEND 0x00000001UL
#define PACKET__RECV 0x00000002UL
#define PACKET__RELABELTO 0x00000004UL
+
+#define KEY__VIEW 0x00000001UL
+#define KEY__READ 0x00000002UL
+#define KEY__WRITE 0x00000004UL
+#define KEY__SEARCH 0x00000008UL
+#define KEY__LINK 0x00000010UL
+#define KEY__SETATTR 0x00000020UL
+
diff --git a/security/selinux/include/class_to_string.h b/security/selinux/include/class_to_string.h
index 3aec75fee4f..24303b61309 100644
--- a/security/selinux/include/class_to_string.h
+++ b/security/selinux/include/class_to_string.h
@@ -60,3 +60,4 @@
S_("netlink_kobject_uevent_socket")
S_("appletalk_socket")
S_("packet")
+ S_("key")
diff --git a/security/selinux/include/flask.h b/security/selinux/include/flask.h
index a0eb9e281d1..95887aed2a6 100644
--- a/security/selinux/include/flask.h
+++ b/security/selinux/include/flask.h
@@ -62,6 +62,7 @@
#define SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET 55
#define SECCLASS_APPLETALK_SOCKET 56
#define SECCLASS_PACKET 57
+#define SECCLASS_KEY 58
/*
* Security identifier indices for initial entities
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 54c03077888..8f5547ad185 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -99,6 +99,11 @@ struct sk_security_struct {
u32 peer_sid; /* SID of peer */
};
+struct key_security_struct {
+ struct key *obj; /* back pointer */
+ u32 sid; /* SID of key */
+};
+
extern unsigned int selinux_checkreqprot;
#endif /* _SELINUX_OBJSEC_H_ */
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index 2e73d3279f2..7029bbc9bef 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -1345,10 +1345,11 @@ err:
goto out;
}
-static struct super_block *sel_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+static int sel_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data,
+ struct vfsmount *mnt)
{
- return get_sb_single(fs_type, flags, data, sel_fill_super);
+ return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
}
static struct file_system_type sel_fs_type = {
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-16 02:47:51 +0000