diff options
Diffstat (limited to 'security/keys')
-rw-r--r-- | security/keys/internal.h | 4 | ||||
-rw-r--r-- | security/keys/key.c | 71 | ||||
-rw-r--r-- | security/keys/keyctl.c | 63 | ||||
-rw-r--r-- | security/keys/keyring.c | 28 | ||||
-rw-r--r-- | security/keys/proc.c | 7 | ||||
-rw-r--r-- | security/keys/process_keys.c | 69 | ||||
-rw-r--r-- | security/keys/request_key.c | 64 | ||||
-rw-r--r-- | security/keys/request_key_auth.c | 49 | ||||
-rw-r--r-- | security/keys/user_defined.c | 25 |
9 files changed, 289 insertions, 91 deletions
diff --git a/security/keys/internal.h b/security/keys/internal.h index e066e605795..1bb416f4bbc 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -99,7 +99,9 @@ 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); + void *aux, + struct key *dest_keyring, + unsigned long flags); /* * request_key authorisation diff --git a/security/keys/key.c b/security/keys/key.c index b6061fa29da..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; @@ -204,19 +206,18 @@ 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 (!parent->rb_parent) + if (!rb_parent(parent)) p = &key_serial_tree.rb_node; - else if (parent->rb_parent->rb_left == parent) - p = &parent->rb_parent->rb_left; + else if (rb_parent(parent)->rb_left == parent) + p = &(rb_parent(parent)->rb_left); else - p = &parent->rb_parent->rb_right; + p = &(rb_parent(parent)->rb_right); parent = rb_next(parent); if (!parent) @@ -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); @@ -247,8 +248,8 @@ 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, 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); + 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, - perm, not_in_quota); + current, perm, flags); if (IS_ERR(key)) { key_ref = ERR_PTR(PTR_ERR(key)); goto error_3; @@ -907,6 +910,10 @@ 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() */ @@ -982,7 +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..d9ca15c109c 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); @@ -183,8 +183,9 @@ 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 = request_key_and_link(ktype, description, callout_info, NULL, + 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 bffa924c1f8..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, @@ -240,15 +242,16 @@ 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, unsigned long flags, + 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); + flags); if (!IS_ERR(keyring)) { ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL); @@ -952,3 +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 217a0bef3c8..32150cf7c37 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 +77,8 @@ 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, 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; @@ -86,8 +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, 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); @@ -143,7 +145,8 @@ int install_thread_keyring(struct task_struct *tsk) sprintf(buf, "_tid.%u", tsk->pid); - keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 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; @@ -177,7 +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, 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; @@ -208,6 +212,7 @@ error: static int install_session_keyring(struct task_struct *tsk, struct key *keyring) { + unsigned long flags; struct key *old; char buf[20]; @@ -217,7 +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, 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); } @@ -390,6 +400,8 @@ 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 +507,35 @@ 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 +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, 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 f030a0ccbb9..f573ac189a0 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -1,6 +1,6 @@ /* request_key.c: request a key from userspace * - * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved. + * Copyright (C) 2004-6 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or @@ -33,7 +33,8 @@ DECLARE_WAIT_QUEUE_HEAD(request_key_conswq); */ static int call_sbin_request_key(struct key *key, struct key *authkey, - const char *op) + const char *op, + void *aux) { struct task_struct *tsk = current; key_serial_t prkey, sskey; @@ -48,7 +49,8 @@ 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, + KEY_ALLOC_QUOTA_OVERRUN, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error_alloc; @@ -125,7 +127,9 @@ error_alloc: */ static struct key *__request_key_construction(struct key_type *type, const char *description, - const char *callout_info) + const char *callout_info, + void *aux, + unsigned long flags) { request_key_actor_t actor; struct key_construction cons; @@ -133,11 +137,12 @@ 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, KEY_POS_ALL, 0); + current->fsuid, current->fsgid, current, KEY_POS_ALL, + flags); if (IS_ERR(key)) goto alloc_failed; @@ -161,7 +166,7 @@ static struct key *__request_key_construction(struct key_type *type, actor = call_sbin_request_key; if (type->request_key) actor = type->request_key; - ret = actor(key, authkey, "create"); + ret = actor(key, authkey, "create", aux); if (ret < 0) goto request_failed; @@ -255,16 +260,18 @@ alloc_failed: */ static struct key *request_key_construction(struct key_type *type, const char *description, + const char *callout_info, + void *aux, struct key_user *user, - 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); @@ -280,7 +287,8 @@ 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, aux, + flags); error: kleave(" = %p", key); return key; @@ -387,14 +395,17 @@ 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) + void *aux, + 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,%p,%lx", + type->name, description, callout_info, aux, + dest_keyring, flags); /* search all the process keyrings for a key */ key_ref = search_process_keyrings(type, description, type->match, @@ -427,7 +438,8 @@ 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); + callout_info, aux, + user, flags); if (key) break; @@ -483,8 +495,28 @@ 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, + NULL, KEY_ALLOC_IN_QUOTA); } /* end request_key() */ EXPORT_SYMBOL(request_key); + +/*****************************************************************************/ +/* + * request a key with auxiliary data for the upcaller + * - search the process's keyrings + * - check the list of keys being created or updated + * - call out to userspace for a key if supplementary info was provided + */ +struct key *request_key_with_auxdata(struct key_type *type, + const char *description, + const char *callout_info, + void *aux) +{ + return request_key_and_link(type, description, callout_info, aux, + NULL, KEY_ALLOC_IN_QUOTA); + +} /* end request_key_with_auxdata() */ + +EXPORT_SYMBOL(request_key_with_auxdata); diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index cce6ba6b032..cbf58a91b00 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(¤t->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, + ¤t->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(¤t->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); @@ -148,9 +185,9 @@ 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); + KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA); if (IS_ERR(authkey)) { ret = PTR_ERR(authkey); goto error_alloc; @@ -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(¤t->request_key_auth->sem); + kfree(rka); + kleave("= -EKEYREVOKED"); + return ERR_PTR(-EKEYREVOKED); + error_inst: key_revoke(authkey); key_put(authkey); 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) { |