diff options
Diffstat (limited to 'security')
-rw-r--r-- | security/Kconfig | 20 | ||||
-rw-r--r-- | security/dummy.c | 3 | ||||
-rw-r--r-- | security/keys/internal.h | 3 | ||||
-rw-r--r-- | security/keys/key.c | 57 | ||||
-rw-r--r-- | security/keys/keyctl.c | 61 | ||||
-rw-r--r-- | security/keys/keyring.c | 25 | ||||
-rw-r--r-- | security/keys/proc.c | 7 | ||||
-rw-r--r-- | security/keys/process_keys.c | 24 | ||||
-rw-r--r-- | security/keys/request_key.c | 36 | ||||
-rw-r--r-- | security/keys/request_key_auth.c | 2 | ||||
-rw-r--r-- | security/keys/user_defined.c | 25 | ||||
-rw-r--r-- | security/selinux/hooks.c | 56 | ||||
-rw-r--r-- | security/selinux/include/av_perm_to_string.h | 3 | ||||
-rw-r--r-- | security/selinux/include/av_permissions.h | 4 | ||||
-rw-r--r-- | security/selinux/include/objsec.h | 2 |
15 files changed, 247 insertions, 81 deletions
diff --git a/security/Kconfig b/security/Kconfig index 34f593410d5..67785df264e 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -22,16 +22,22 @@ config KEYS If you are unsure as to whether this is required, answer N. config KEYS_DEBUG_PROC_KEYS - bool "Enable the /proc/keys file by which all keys may be viewed" + bool "Enable the /proc/keys file by which keys may be viewed" depends on KEYS help - This option turns on support for the /proc/keys file through which - all the keys on the system can be listed. + This option turns on support for the /proc/keys file - through which + can be listed all the keys on the system that are viewable by the + reading process. - This option is a slight security risk in that it makes it possible - for anyone to see all the keys on the system. Normally the manager - pretends keys that are inaccessible to a process don't exist as far - as that process is concerned. + The only keys included in the list are those that grant View + permission to the reading process whether or not it possesses them. + Note that LSM security checks are still performed, and may further + filter out keys that the current process is not authorised to view. + + Only key attributes are listed here; key payloads are not included in + the resulting table. + + If you are unsure as to whether this is required, answer N. config SECURITY bool "Enable different security models" diff --git a/security/dummy.c b/security/dummy.c index c3c5493581e..310fcdf7b74 100644 --- a/security/dummy.c +++ b/security/dummy.c @@ -870,7 +870,8 @@ 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, struct task_struct *ctx) +static inline int dummy_key_alloc(struct key *key, struct task_struct *ctx, + unsigned long flags) { return 0; } diff --git a/security/keys/internal.h b/security/keys/internal.h index e066e605795..3c2877f0663 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -99,7 +99,8 @@ extern int install_process_keyring(struct task_struct *tsk); extern struct key *request_key_and_link(struct key_type *type, const char *description, const char *callout_info, - struct key *dest_keyring); + struct key *dest_keyring, + unsigned long flags); /* * request_key authorisation diff --git a/security/keys/key.c b/security/keys/key.c index 51f85155738..80de8c3e9cc 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -11,15 +11,16 @@ #include <linux/module.h> #include <linux/init.h> +#include <linux/poison.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/security.h> #include <linux/workqueue.h> +#include <linux/random.h> #include <linux/err.h> #include "internal.h" static kmem_cache_t *key_jar; -static key_serial_t key_serial_next = 3; struct rb_root key_serial_tree; /* tree of keys indexed by serial */ DEFINE_SPINLOCK(key_serial_lock); @@ -169,22 +170,23 @@ static void __init __key_insert_serial(struct key *key) /*****************************************************************************/ /* * assign a key the next unique serial number - * - we work through all the serial numbers between 2 and 2^31-1 in turn and - * then wrap + * - these are assigned randomly to avoid security issues through covert + * channel problems */ static inline void key_alloc_serial(struct key *key) { struct rb_node *parent, **p; struct key *xkey; - spin_lock(&key_serial_lock); - - /* propose a likely serial number and look for a hole for it in the + /* propose a random serial number and look for a hole for it in the * serial number tree */ - key->serial = key_serial_next; - if (key->serial < 3) - key->serial = 3; - key_serial_next = key->serial + 1; + do { + get_random_bytes(&key->serial, sizeof(key->serial)); + + key->serial >>= 1; /* negative numbers are not permitted */ + } while (key->serial < 3); + + spin_lock(&key_serial_lock); parent = NULL; p = &key_serial_tree.rb_node; @@ -204,12 +206,11 @@ static inline void key_alloc_serial(struct key *key) /* we found a key with the proposed serial number - walk the tree from * that point looking for the next unused serial number */ - serial_exists: +serial_exists: for (;;) { - key->serial = key_serial_next; + key->serial++; if (key->serial < 2) key->serial = 2; - key_serial_next = key->serial + 1; if (!rb_parent(parent)) p = &key_serial_tree.rb_node; @@ -228,7 +229,7 @@ static inline void key_alloc_serial(struct key *key) } /* we've found a suitable hole - arrange for this key to occupy it */ - insert_here: +insert_here: rb_link_node(&key->serial_node, parent, p); rb_insert_color(&key->serial_node, &key_serial_tree); @@ -248,7 +249,7 @@ static inline void key_alloc_serial(struct key *key) */ struct key *key_alloc(struct key_type *type, const char *desc, uid_t uid, gid_t gid, struct task_struct *ctx, - key_perm_t perm, int not_in_quota) + key_perm_t perm, unsigned long flags) { struct key_user *user = NULL; struct key *key; @@ -269,12 +270,14 @@ struct key *key_alloc(struct key_type *type, const char *desc, /* check that the user's quota permits allocation of another key and * its description */ - if (!not_in_quota) { + if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { spin_lock(&user->lock); - if (user->qnkeys + 1 >= KEYQUOTA_MAX_KEYS || - user->qnbytes + quotalen >= KEYQUOTA_MAX_BYTES - ) - goto no_quota; + if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) { + if (user->qnkeys + 1 >= KEYQUOTA_MAX_KEYS || + user->qnbytes + quotalen >= KEYQUOTA_MAX_BYTES + ) + goto no_quota; + } user->qnkeys++; user->qnbytes += quotalen; @@ -308,7 +311,7 @@ struct key *key_alloc(struct key_type *type, const char *desc, key->payload.data = NULL; key->security = NULL; - if (!not_in_quota) + if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) key->flags |= 1 << KEY_FLAG_IN_QUOTA; memset(&key->type_data, 0, sizeof(key->type_data)); @@ -318,7 +321,7 @@ 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, ctx); + ret = security_key_alloc(key, ctx, flags); if (ret < 0) goto security_error; @@ -332,7 +335,7 @@ error: security_error: kfree(key->description); kmem_cache_free(key_jar, key); - if (!not_in_quota) { + if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { spin_lock(&user->lock); user->qnkeys--; user->qnbytes -= quotalen; @@ -345,7 +348,7 @@ security_error: no_memory_3: kmem_cache_free(key_jar, key); no_memory_2: - if (!not_in_quota) { + if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { spin_lock(&user->lock); user->qnkeys--; user->qnbytes -= quotalen; @@ -761,7 +764,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, const char *description, const void *payload, size_t plen, - int not_in_quota) + unsigned long flags) { struct key_type *ktype; struct key *keyring, *key = NULL; @@ -822,7 +825,7 @@ 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, - current, perm, not_in_quota); + current, perm, flags); if (IS_ERR(key)) { key_ref = ERR_PTR(PTR_ERR(key)); goto error_3; @@ -986,7 +989,7 @@ void unregister_key_type(struct key_type *ktype) if (key->type == ktype) { if (ktype->destroy) ktype->destroy(key); - memset(&key->payload, 0xbd, sizeof(key->payload)); + memset(&key->payload, KEY_DESTROY, sizeof(key->payload)); } } diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index ed71d86d2ce..329411cf876 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -102,7 +102,7 @@ asmlinkage long sys_add_key(const char __user *_type, /* create or update the requested key and add it to the target * keyring */ key_ref = key_create_or_update(keyring_ref, type, description, - payload, plen, 0); + payload, plen, KEY_ALLOC_IN_QUOTA); if (!IS_ERR(key_ref)) { ret = key_ref_to_ptr(key_ref)->serial; key_ref_put(key_ref); @@ -184,7 +184,8 @@ asmlinkage long sys_request_key(const char __user *_type, /* do the search */ key = request_key_and_link(ktype, description, callout_info, - key_ref_to_ptr(dest_ref)); + key_ref_to_ptr(dest_ref), + KEY_ALLOC_IN_QUOTA); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error5; @@ -672,6 +673,7 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) */ long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid) { + struct key_user *newowner, *zapowner = NULL; struct key *key; key_ref_t key_ref; long ret; @@ -695,19 +697,50 @@ long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid) if (!capable(CAP_SYS_ADMIN)) { /* only the sysadmin can chown a key to some other UID */ if (uid != (uid_t) -1 && key->uid != uid) - goto no_access; + goto error_put; /* only the sysadmin can set the key's GID to a group other * than one of those that the current process subscribes to */ if (gid != (gid_t) -1 && gid != key->gid && !in_group_p(gid)) - goto no_access; + goto error_put; } - /* change the UID (have to update the quotas) */ + /* change the UID */ if (uid != (uid_t) -1 && uid != key->uid) { - /* don't support UID changing yet */ - ret = -EOPNOTSUPP; - goto no_access; + ret = -ENOMEM; + newowner = key_user_lookup(uid); + if (!newowner) + goto error_put; + + /* transfer the quota burden to the new user */ + if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) { + spin_lock(&newowner->lock); + if (newowner->qnkeys + 1 >= KEYQUOTA_MAX_KEYS || + newowner->qnbytes + key->quotalen >= + KEYQUOTA_MAX_BYTES) + goto quota_overrun; + + newowner->qnkeys++; + newowner->qnbytes += key->quotalen; + spin_unlock(&newowner->lock); + + spin_lock(&key->user->lock); + key->user->qnkeys--; + key->user->qnbytes -= key->quotalen; + spin_unlock(&key->user->lock); + } + + atomic_dec(&key->user->nkeys); + atomic_inc(&newowner->nkeys); + + if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { + atomic_dec(&key->user->nikeys); + atomic_inc(&newowner->nikeys); + } + + zapowner = key->user; + key->user = newowner; + key->uid = uid; } /* change the GID */ @@ -716,12 +749,20 @@ long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid) ret = 0; - no_access: +error_put: up_write(&key->sem); key_put(key); - error: + if (zapowner) + key_user_put(zapowner); +error: return ret; +quota_overrun: + spin_unlock(&newowner->lock); + zapowner = newowner; + ret = -EDQUOT; + goto error_put; + } /* end keyctl_chown_key() */ /*****************************************************************************/ diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 1357207fc9d..e8d02acc51e 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -49,6 +49,7 @@ static inline unsigned keyring_hash(const char *desc) static int keyring_instantiate(struct key *keyring, const void *data, size_t datalen); static int keyring_match(const struct key *keyring, const void *criterion); +static void keyring_revoke(struct key *keyring); static void keyring_destroy(struct key *keyring); static void keyring_describe(const struct key *keyring, struct seq_file *m); static long keyring_read(const struct key *keyring, @@ -59,6 +60,7 @@ struct key_type key_type_keyring = { .def_datalen = sizeof(struct keyring_list), .instantiate = keyring_instantiate, .match = keyring_match, + .revoke = keyring_revoke, .destroy = keyring_destroy, .describe = keyring_describe, .read = keyring_read, @@ -240,7 +242,7 @@ 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, - struct task_struct *ctx, int not_in_quota, + struct task_struct *ctx, unsigned long flags, struct key *dest) { struct key *keyring; @@ -249,7 +251,7 @@ struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid, keyring = key_alloc(&key_type_keyring, description, uid, gid, ctx, (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL, - not_in_quota); + flags); if (!IS_ERR(keyring)) { ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL); @@ -953,3 +955,22 @@ int keyring_clear(struct key *keyring) } /* end keyring_clear() */ EXPORT_SYMBOL(keyring_clear); + +/*****************************************************************************/ +/* + * dispose of the links from a revoked keyring + * - called with the key sem write-locked + */ +static void keyring_revoke(struct key *keyring) +{ + struct keyring_list *klist = keyring->payload.subscriptions; + + /* adjust the quota */ + key_payload_reserve(keyring, 0); + + if (klist) { + rcu_assign_pointer(keyring->payload.subscriptions, NULL); + call_rcu(&klist->rcu, keyring_clear_rcu_disposal); + } + +} /* end keyring_revoke() */ diff --git a/security/keys/proc.c b/security/keys/proc.c index 12b750e51fb..686a9ee0c5d 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -137,6 +137,13 @@ static int proc_keys_show(struct seq_file *m, void *v) struct timespec now; unsigned long timo; char xbuf[12]; + int rc; + + /* check whether the current task is allowed to view the key (assuming + * non-possession) */ + rc = key_task_permission(make_key_ref(key, 0), current, KEY_VIEW); + if (rc < 0) + return 0; now = current_kernel_time(); diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 4d9825f9962..32150cf7c37 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -77,7 +77,8 @@ 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, ctx, 0, NULL); + session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, + KEY_ALLOC_IN_QUOTA, NULL); if (IS_ERR(session_keyring)) { ret = PTR_ERR(session_keyring); goto error; @@ -87,8 +88,8 @@ 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, ctx, 0, - session_keyring); + uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, + KEY_ALLOC_IN_QUOTA, session_keyring); if (IS_ERR(uid_keyring)) { key_put(session_keyring); ret = PTR_ERR(uid_keyring); @@ -144,7 +145,8 @@ int install_thread_keyring(struct task_struct *tsk) sprintf(buf, "_tid.%u", tsk->pid); - keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL); + keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, + KEY_ALLOC_QUOTA_OVERRUN, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error; @@ -178,7 +180,8 @@ 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, tsk, 1, NULL); + keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, + KEY_ALLOC_QUOTA_OVERRUN, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error; @@ -209,6 +212,7 @@ error: static int install_session_keyring(struct task_struct *tsk, struct key *keyring) { + unsigned long flags; struct key *old; char buf[20]; @@ -218,7 +222,12 @@ 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, tsk, 1, NULL); + flags = KEY_ALLOC_QUOTA_OVERRUN; + if (tsk->signal->session_keyring) + flags = KEY_ALLOC_IN_QUOTA; + + keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, + flags, NULL); if (IS_ERR(keyring)) return PTR_ERR(keyring); } @@ -728,7 +737,8 @@ 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, tsk, 0, NULL); + keyring = keyring_alloc(name, tsk->uid, tsk->gid, tsk, + KEY_ALLOC_IN_QUOTA, 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 eab66a06ca5..58d1efd4fc2 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -48,8 +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, - current, 1, NULL); + keyring = keyring_alloc(desc, current->fsuid, current->fsgid, current, + KEY_ALLOC_QUOTA_OVERRUN, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error_alloc; @@ -126,7 +126,8 @@ error_alloc: */ static struct key *__request_key_construction(struct key_type *type, const char *description, - const char *callout_info) + const char *callout_info, + unsigned long flags) { request_key_actor_t actor; struct key_construction cons; @@ -134,12 +135,12 @@ static struct key *__request_key_construction(struct key_type *type, struct key *key, *authkey; int ret, negated; - kenter("%s,%s,%s", type->name, description, callout_info); + kenter("%s,%s,%s,%lx", type->name, description, callout_info, flags); /* create a key and add it to the queue */ key = key_alloc(type, description, - current->fsuid, current->fsgid, - current, KEY_POS_ALL, 0); + current->fsuid, current->fsgid, current, KEY_POS_ALL, + flags); if (IS_ERR(key)) goto alloc_failed; @@ -258,15 +259,16 @@ alloc_failed: static struct key *request_key_construction(struct key_type *type, const char *description, struct key_user *user, - const char *callout_info) + const char *callout_info, + unsigned long flags) { struct key_construction *pcons; struct key *key, *ckey; DECLARE_WAITQUEUE(myself, current); - kenter("%s,%s,{%d},%s", - type->name, description, user->uid, callout_info); + kenter("%s,%s,{%d},%s,%lx", + type->name, description, user->uid, callout_info, flags); /* see if there's such a key under construction already */ down_write(&key_construction_sem); @@ -282,7 +284,8 @@ static struct key *request_key_construction(struct key_type *type, } /* see about getting userspace to construct the key */ - key = __request_key_construction(type, description, callout_info); + key = __request_key_construction(type, description, callout_info, + flags); error: kleave(" = %p", key); return key; @@ -389,14 +392,15 @@ static void request_key_link(struct key *key, struct key *dest_keyring) struct key *request_key_and_link(struct key_type *type, const char *description, const char *callout_info, - struct key *dest_keyring) + struct key *dest_keyring, + unsigned long flags) { struct key_user *user; struct key *key; key_ref_t key_ref; - kenter("%s,%s,%s,%p", - type->name, description, callout_info, dest_keyring); + kenter("%s,%s,%s,%p,%lx", + type->name, description, callout_info, dest_keyring, flags); /* search all the process keyrings for a key */ key_ref = search_process_keyrings(type, description, type->match, @@ -429,7 +433,8 @@ struct key *request_key_and_link(struct key_type *type, /* ask userspace (returns NULL if it waited on a key * being constructed) */ key = request_key_construction(type, description, - user, callout_info); + user, callout_info, + flags); if (key) break; @@ -485,7 +490,8 @@ struct key *request_key(struct key_type *type, const char *description, const char *callout_info) { - return request_key_and_link(type, description, callout_info, NULL); + return request_key_and_link(type, description, callout_info, NULL, + KEY_ALLOC_IN_QUOTA); } /* end request_key() */ diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index cb9817ced3f..cbf58a91b00 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -187,7 +187,7 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info) authkey = key_alloc(&key_type_request_key_auth, desc, current->fsuid, current->fsgid, current, KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH | - KEY_USR_VIEW, 1); + KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA); if (IS_ERR(authkey)) { ret = PTR_ERR(authkey); goto error_alloc; diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c index 8e71895b97a..5bbfdebb7ac 100644 --- a/security/keys/user_defined.c +++ b/security/keys/user_defined.c @@ -28,6 +28,7 @@ struct key_type key_type_user = { .instantiate = user_instantiate, .update = user_update, .match = user_match, + .revoke = user_revoke, .destroy = user_destroy, .describe = user_describe, .read = user_read, @@ -67,6 +68,7 @@ error: return ret; } /* end user_instantiate() */ + EXPORT_SYMBOL_GPL(user_instantiate); /*****************************************************************************/ @@ -141,7 +143,28 @@ EXPORT_SYMBOL_GPL(user_match); /*****************************************************************************/ /* - * dispose of the data dangling from the corpse of a user + * dispose of the links from a revoked keyring + * - called with the key sem write-locked + */ +void user_revoke(struct key *key) +{ + struct user_key_payload *upayload = key->payload.data; + + /* clear the quota */ + key_payload_reserve(key, 0); + + if (upayload) { + rcu_assign_pointer(key->payload.data, NULL); + call_rcu(&upayload->rcu, user_update_rcu_disposal); + } + +} /* end user_revoke() */ + +EXPORT_SYMBOL(user_revoke); + +/*****************************************************************************/ +/* + * dispose of the data dangling from the corpse of a user key */ void user_destroy(struct key *key) { diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 79c16e31c88..28832e68980 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1099,6 +1099,17 @@ static int may_create(struct inode *dir, FILESYSTEM__ASSOCIATE, &ad); } +/* Check whether a task can create a key. */ +static int may_create_key(u32 ksid, + struct task_struct *ctx) +{ + struct task_security_struct *tsec; + + tsec = ctx->security; + + return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); +} + #define MAY_LINK 0 #define MAY_UNLINK 1 #define MAY_RMDIR 2 @@ -1521,8 +1532,10 @@ static int selinux_bprm_set_security(struct linux_binprm *bprm) /* Default to the current task SID. */ bsec->sid = tsec->sid; - /* Reset create SID on execve. */ + /* Reset fs, key, and sock SIDs on execve. */ tsec->create_sid = 0; + tsec->keycreate_sid = 0; + tsec->sockcreate_sid = 0; if (tsec->exec_sid) { newsid = tsec->exec_sid; @@ -2574,9 +2587,11 @@ static int selinux_task_alloc_security(struct task_struct *tsk) tsec2->osid = tsec1->osid; tsec2->sid = tsec1->sid; - /* Retain the exec and create SIDs across fork */ + /* Retain the exec, fs, key, and sock SIDs across fork */ tsec2->exec_sid = tsec1->exec_sid; tsec2->create_sid = tsec1->create_sid; + tsec2->keycreate_sid = tsec1->keycreate_sid; + tsec2->sockcreate_sid = tsec1->sockcreate_sid; /* Retain ptracer SID across fork, if any. This will be reset by the ptrace hook upon any @@ -2926,12 +2941,14 @@ static int selinux_socket_create(int family, int type, { int err = 0; struct task_security_struct *tsec; + u32 newsid; if (kern) goto out; tsec = current->security; - err = avc_has_perm(tsec->sid, tsec->sid, + newsid = tsec->sockcreate_sid ? : tsec->sid; + err = avc_has_perm(tsec->sid, newsid, socket_type_to_security_class(family, type, protocol), SOCKET__CREATE, NULL); @@ -2944,12 +2961,14 @@ static void selinux_socket_post_create(struct socket *sock, int family, { struct inode_security_struct *isec; struct task_security_struct *tsec; + u32 newsid; isec = SOCK_INODE(sock)->i_security; tsec = current->security; + newsid = tsec->sockcreate_sid ? : tsec->sid; isec->sclass = socket_type_to_security_class(family, type, protocol); - isec->sid = kern ? SECINITSID_KERNEL : tsec->sid; + isec->sid = kern ? SECINITSID_KERNEL : newsid; isec->initialized = 1; return; @@ -4150,6 +4169,10 @@ static int selinux_getprocattr(struct task_struct *p, sid = tsec->exec_sid; else if (!strcmp(name, "fscreate")) sid = tsec->create_sid; + else if (!strcmp(name, "keycreate")) + sid = tsec->keycreate_sid; + else if (!strcmp(name, "sockcreate")) + sid = tsec->sockcreate_sid; else return -EINVAL; @@ -4182,6 +4205,10 @@ static int selinux_setprocattr(struct task_struct *p, error = task_has_perm(current, p, PROCESS__SETEXEC); else if (!strcmp(name, "fscreate")) error = task_has_perm(current, p, PROCESS__SETFSCREATE); + else if (!strcmp(name, "keycreate")) + error = task_has_perm(current, p, PROCESS__SETKEYCREATE); + else if (!strcmp(name, "sockcreate")) + error = task_has_perm(current, p, PROCESS__SETSOCKCREATE); else if (!strcmp(name, "current")) error = task_has_perm(current, p, PROCESS__SETCURRENT); else @@ -4211,6 +4238,13 @@ static int selinux_setprocattr(struct task_struct *p, tsec->exec_sid = sid; else if (!strcmp(name, "fscreate")) tsec->create_sid = sid; + else if (!strcmp(name, "keycreate")) { + error = may_create_key(sid, p); + if (error) + return error; + tsec->keycreate_sid = sid; + } else if (!strcmp(name, "sockcreate")) + tsec->sockcreate_sid = sid; else if (!strcmp(name, "current")) { struct av_decision avd; @@ -4264,7 +4298,8 @@ static int selinux_setprocattr(struct task_struct *p, #ifdef CONFIG_KEYS -static int selinux_key_alloc(struct key *k, struct task_struct *tsk) +static int selinux_key_alloc(struct key *k, struct task_struct *tsk, + unsigned long flags) { struct task_security_struct *tsec = tsk->security; struct key_security_struct *ksec; @@ -4274,7 +4309,10 @@ static int selinux_key_alloc(struct key *k, struct task_struct *tsk) return -ENOMEM; ksec->obj = k; - ksec->sid = tsec->sid; + if (tsec->keycreate_sid) + ksec->sid = tsec->keycreate_sid; + else + ksec->sid = tsec->sid; k->security = ksec; return 0; @@ -4513,8 +4551,10 @@ static __init int selinux_init(void) #ifdef CONFIG_KEYS /* Add security information to initial keyrings */ - security_key_alloc(&root_user_keyring, current); - security_key_alloc(&root_session_keyring, current); + selinux_key_alloc(&root_user_keyring, current, + KEY_ALLOC_NOT_IN_QUOTA); + selinux_key_alloc(&root_session_keyring, current, + KEY_ALLOC_NOT_IN_QUOTA); #endif return 0; diff --git a/security/selinux/include/av_perm_to_string.h b/security/selinux/include/av_perm_to_string.h index bc020bde6c8..7c9b5838083 100644 --- a/security/selinux/include/av_perm_to_string.h +++ b/security/selinux/include/av_perm_to_string.h @@ -72,6 +72,8 @@ S_(SECCLASS_PROCESS, PROCESS__EXECMEM, "execmem") S_(SECCLASS_PROCESS, PROCESS__EXECSTACK, "execstack") S_(SECCLASS_PROCESS, PROCESS__EXECHEAP, "execheap") + S_(SECCLASS_PROCESS, PROCESS__SETKEYCREATE, "setkeycreate") + S_(SECCLASS_PROCESS, PROCESS__SETSOCKCREATE, "setsockcreate") S_(SECCLASS_MSGQ, MSGQ__ENQUEUE, "enqueue") S_(SECCLASS_MSG, MSG__SEND, "send") S_(SECCLASS_MSG, MSG__RECEIVE, "receive") @@ -248,3 +250,4 @@ S_(SECCLASS_KEY, KEY__SEARCH, "search") S_(SECCLASS_KEY, KEY__LINK, "link") S_(SECCLASS_KEY, KEY__SETATTR, "setattr") + S_(SECCLASS_KEY, KEY__CREATE, "create") diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h index 1205227a3a3..69fd4b48202 100644 --- a/security/selinux/include/av_permissions.h +++ b/security/selinux/include/av_permissions.h @@ -467,6 +467,8 @@ #define PROCESS__EXECMEM 0x02000000UL #define PROCESS__EXECSTACK 0x04000000UL #define PROCESS__EXECHEAP 0x08000000UL +#define PROCESS__SETKEYCREATE 0x10000000UL +#define PROCESS__SETSOCKCREATE 0x20000000UL #define IPC__CREATE 0x00000001UL #define IPC__DESTROY 0x00000002UL @@ -966,4 +968,4 @@ #define KEY__SEARCH 0x00000008UL #define KEY__LINK 0x00000010UL #define KEY__SETATTR 0x00000020UL - +#define KEY__CREATE 0x00000040UL diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h index 8f5547ad185..cf54a304169 100644 --- a/security/selinux/include/objsec.h +++ b/security/selinux/include/objsec.h @@ -32,6 +32,8 @@ struct task_security_struct { u32 sid; /* current SID */ u32 exec_sid; /* exec SID */ u32 create_sid; /* fscreate SID */ + u32 keycreate_sid; /* keycreate SID */ + u32 sockcreate_sid; /* fscreate SID */ u32 ptrace_sid; /* SID of ptrace parent */ }; |