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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-16 15:40:50 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-16 15:40:50 -0800 |
commit | 2a74dbb9a86e8102dcd07d284135b4530a84826e (patch) | |
tree | a54403e312b6062dfb57bd904ba8b8ce3b11e720 /security/keys | |
parent | 770b6cb4d21fb3e3df2a7a51e186a3c14db1ec30 (diff) | |
parent | e93072374112db9dc86635934ee761249be28370 (diff) | |
download | linux-3.10-2a74dbb9a86e8102dcd07d284135b4530a84826e.tar.gz linux-3.10-2a74dbb9a86e8102dcd07d284135b4530a84826e.tar.bz2 linux-3.10-2a74dbb9a86e8102dcd07d284135b4530a84826e.zip |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"A quiet cycle for the security subsystem with just a few maintenance
updates."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
Smack: create a sysfs mount point for smackfs
Smack: use select not depends in Kconfig
Yama: remove locking from delete path
Yama: add RCU to drop read locking
drivers/char/tpm: remove tasklet and cleanup
KEYS: Use keyring_alloc() to create special keyrings
KEYS: Reduce initial permissions on keys
KEYS: Make the session and process keyrings per-thread
seccomp: Make syscall skipping and nr changes more consistent
key: Fix resource leak
keys: Fix unreachable code
KEYS: Add payload preparsing opportunity prior to key instantiate or update
Diffstat (limited to 'security/keys')
-rw-r--r-- | security/keys/key.c | 6 | ||||
-rw-r--r-- | security/keys/keyctl.c | 15 | ||||
-rw-r--r-- | security/keys/keyring.c | 10 | ||||
-rw-r--r-- | security/keys/process_keys.c | 92 | ||||
-rw-r--r-- | security/keys/request_key.c | 21 |
5 files changed, 69 insertions, 75 deletions
diff --git a/security/keys/key.c b/security/keys/key.c index a15c9da8f97..8fb7c7bd465 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -854,13 +854,13 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, /* if the client doesn't provide, decide on the permissions we want */ if (perm == KEY_PERM_UNDEF) { perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; - perm |= KEY_USR_VIEW | KEY_USR_SEARCH | KEY_USR_LINK | KEY_USR_SETATTR; + perm |= KEY_USR_VIEW; if (ktype->read) - perm |= KEY_POS_READ | KEY_USR_READ; + perm |= KEY_POS_READ; if (ktype == &key_type_keyring || ktype->update) - perm |= KEY_USR_WRITE; + perm |= KEY_POS_WRITE; } /* allocate a new key */ diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 5d34b4e827d..4b5c948eb41 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -1132,12 +1132,12 @@ long keyctl_instantiate_key_iov(key_serial_t id, ret = rw_copy_check_uvector(WRITE, _payload_iov, ioc, ARRAY_SIZE(iovstack), iovstack, &iov); if (ret < 0) - return ret; + goto err; if (ret == 0) goto no_payload_free; ret = keyctl_instantiate_key_common(id, iov, ioc, ret, ringid); - +err: if (iov != iovstack) kfree(iov); return ret; @@ -1495,7 +1495,8 @@ long keyctl_session_to_parent(void) goto error_keyring; newwork = &cred->rcu; - cred->tgcred->session_keyring = key_ref_to_ptr(keyring_r); + cred->session_keyring = key_ref_to_ptr(keyring_r); + keyring_r = NULL; init_task_work(newwork, key_change_session_keyring); me = current; @@ -1519,7 +1520,7 @@ long keyctl_session_to_parent(void) mycred = current_cred(); pcred = __task_cred(parent); if (mycred == pcred || - mycred->tgcred->session_keyring == pcred->tgcred->session_keyring) { + mycred->session_keyring == pcred->session_keyring) { ret = 0; goto unlock; } @@ -1535,9 +1536,9 @@ long keyctl_session_to_parent(void) goto unlock; /* the keyrings must have the same UID */ - if ((pcred->tgcred->session_keyring && - !uid_eq(pcred->tgcred->session_keyring->uid, mycred->euid)) || - !uid_eq(mycred->tgcred->session_keyring->uid, mycred->euid)) + if ((pcred->session_keyring && + !uid_eq(pcred->session_keyring->uid, mycred->euid)) || + !uid_eq(mycred->session_keyring->uid, mycred->euid)) goto unlock; /* cancel an already pending keyring replacement */ diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 6e42df15a24..6ece7f2e570 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -257,17 +257,14 @@ error: * Allocate a keyring and link into the destination keyring. */ struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid, - const struct cred *cred, unsigned long flags, - struct key *dest) + const struct cred *cred, key_perm_t perm, + unsigned long flags, struct key *dest) { struct key *keyring; int ret; keyring = key_alloc(&key_type_keyring, description, - uid, gid, cred, - (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL, - flags); - + uid, gid, cred, perm, flags); if (!IS_ERR(keyring)) { ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL); if (ret < 0) { @@ -278,6 +275,7 @@ struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid, return keyring; } +EXPORT_SYMBOL(keyring_alloc); /** * keyring_search_aux - Search a keyring tree for a key matching some criteria diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 86468f385fc..58dfe089094 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -45,10 +45,12 @@ int install_user_keyrings(void) struct user_struct *user; const struct cred *cred; struct key *uid_keyring, *session_keyring; + key_perm_t user_keyring_perm; 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); @@ -73,8 +75,8 @@ int install_user_keyrings(void) uid_keyring = find_keyring_by_name(buf, true); if (IS_ERR(uid_keyring)) { uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID, - cred, KEY_ALLOC_IN_QUOTA, - NULL); + cred, user_keyring_perm, + KEY_ALLOC_IN_QUOTA, NULL); if (IS_ERR(uid_keyring)) { ret = PTR_ERR(uid_keyring); goto error; @@ -89,7 +91,8 @@ int install_user_keyrings(void) if (IS_ERR(session_keyring)) { session_keyring = keyring_alloc(buf, user->uid, INVALID_GID, - cred, KEY_ALLOC_IN_QUOTA, NULL); + cred, user_keyring_perm, + KEY_ALLOC_IN_QUOTA, NULL); if (IS_ERR(session_keyring)) { ret = PTR_ERR(session_keyring); goto error_release; @@ -130,6 +133,7 @@ int install_thread_keyring_to_cred(struct cred *new) struct key *keyring; keyring = keyring_alloc("_tid", new->uid, new->gid, new, + KEY_POS_ALL | KEY_USR_VIEW, KEY_ALLOC_QUOTA_OVERRUN, NULL); if (IS_ERR(keyring)) return PTR_ERR(keyring); @@ -170,27 +174,18 @@ static int install_thread_keyring(void) int install_process_keyring_to_cred(struct cred *new) { struct key *keyring; - int ret; - if (new->tgcred->process_keyring) + if (new->process_keyring) return -EEXIST; - keyring = keyring_alloc("_pid", new->uid, new->gid, - new, KEY_ALLOC_QUOTA_OVERRUN, NULL); + keyring = keyring_alloc("_pid", new->uid, new->gid, new, + KEY_POS_ALL | KEY_USR_VIEW, + KEY_ALLOC_QUOTA_OVERRUN, NULL); if (IS_ERR(keyring)) return PTR_ERR(keyring); - spin_lock_irq(&new->tgcred->lock); - if (!new->tgcred->process_keyring) { - new->tgcred->process_keyring = keyring; - keyring = NULL; - ret = 0; - } else { - ret = -EEXIST; - } - spin_unlock_irq(&new->tgcred->lock); - key_put(keyring); - return ret; + new->process_keyring = keyring; + return 0; } /* @@ -231,11 +226,12 @@ int install_session_keyring_to_cred(struct cred *cred, struct key *keyring) /* create an empty session keyring */ if (!keyring) { flags = KEY_ALLOC_QUOTA_OVERRUN; - if (cred->tgcred->session_keyring) + if (cred->session_keyring) flags = KEY_ALLOC_IN_QUOTA; - keyring = keyring_alloc("_ses", cred->uid, cred->gid, - cred, flags, NULL); + keyring = keyring_alloc("_ses", cred->uid, cred->gid, cred, + KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ, + flags, NULL); if (IS_ERR(keyring)) return PTR_ERR(keyring); } else { @@ -243,17 +239,11 @@ int install_session_keyring_to_cred(struct cred *cred, struct key *keyring) } /* install the keyring */ - spin_lock_irq(&cred->tgcred->lock); - old = cred->tgcred->session_keyring; - rcu_assign_pointer(cred->tgcred->session_keyring, keyring); - spin_unlock_irq(&cred->tgcred->lock); - - /* we're using RCU on the pointer, but there's no point synchronising - * on it if it didn't previously point to anything */ - if (old) { - synchronize_rcu(); + old = cred->session_keyring; + rcu_assign_pointer(cred->session_keyring, keyring); + + if (old) key_put(old); - } return 0; } @@ -368,9 +358,9 @@ key_ref_t search_my_process_keyrings(struct key_type *type, } /* search the process keyring second */ - if (cred->tgcred->process_keyring) { + if (cred->process_keyring) { key_ref = keyring_search_aux( - make_key_ref(cred->tgcred->process_keyring, 1), + make_key_ref(cred->process_keyring, 1), cred, type, description, match, no_state_check); if (!IS_ERR(key_ref)) goto found; @@ -389,12 +379,10 @@ key_ref_t search_my_process_keyrings(struct key_type *type, } /* search the session keyring */ - if (cred->tgcred->session_keyring) { + if (cred->session_keyring) { rcu_read_lock(); key_ref = keyring_search_aux( - make_key_ref(rcu_dereference( - cred->tgcred->session_keyring), - 1), + make_key_ref(rcu_dereference(cred->session_keyring), 1), cred, type, description, match, no_state_check); rcu_read_unlock(); @@ -564,7 +552,7 @@ try_again: break; case KEY_SPEC_PROCESS_KEYRING: - if (!cred->tgcred->process_keyring) { + if (!cred->process_keyring) { if (!(lflags & KEY_LOOKUP_CREATE)) goto error; @@ -576,13 +564,13 @@ try_again: goto reget_creds; } - key = cred->tgcred->process_keyring; + key = cred->process_keyring; atomic_inc(&key->usage); key_ref = make_key_ref(key, 1); break; case KEY_SPEC_SESSION_KEYRING: - if (!cred->tgcred->session_keyring) { + if (!cred->session_keyring) { /* always install a session keyring upon access if one * doesn't exist yet */ ret = install_user_keyrings(); @@ -597,7 +585,7 @@ try_again: if (ret < 0) goto error; goto reget_creds; - } else if (cred->tgcred->session_keyring == + } else if (cred->session_keyring == cred->user->session_keyring && lflags & KEY_LOOKUP_CREATE) { ret = join_session_keyring(NULL); @@ -607,7 +595,7 @@ try_again: } rcu_read_lock(); - key = rcu_dereference(cred->tgcred->session_keyring); + key = rcu_dereference(cred->session_keyring); atomic_inc(&key->usage); rcu_read_unlock(); key_ref = make_key_ref(key, 1); @@ -767,12 +755,6 @@ long join_session_keyring(const char *name) struct key *keyring; long ret, serial; - /* only permit this if there's a single thread in the thread group - - * this avoids us having to adjust the creds on all threads and risking - * ENOMEM */ - if (!current_is_single_threaded()) - return -EMLINK; - new = prepare_creds(); if (!new) return -ENOMEM; @@ -784,7 +766,7 @@ long join_session_keyring(const char *name) if (ret < 0) goto error; - serial = new->tgcred->session_keyring->serial; + serial = new->session_keyring->serial; ret = commit_creds(new); if (ret == 0) ret = serial; @@ -798,8 +780,10 @@ long join_session_keyring(const char *name) keyring = find_keyring_by_name(name, false); if (PTR_ERR(keyring) == -ENOKEY) { /* not found - try and create a new one */ - keyring = keyring_alloc(name, old->uid, old->gid, old, - KEY_ALLOC_IN_QUOTA, NULL); + keyring = keyring_alloc( + name, old->uid, old->gid, old, + KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_LINK, + KEY_ALLOC_IN_QUOTA, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error2; @@ -807,6 +791,9 @@ long join_session_keyring(const char *name) } else if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error2; + } else if (keyring == new->session_keyring) { + ret = 0; + goto error2; } /* we've got a keyring - now to install it */ @@ -863,8 +850,7 @@ void key_change_session_keyring(struct callback_head *twork) new->jit_keyring = old->jit_keyring; new->thread_keyring = key_get(old->thread_keyring); - new->tgcred->tgid = old->tgcred->tgid; - new->tgcred->process_keyring = key_get(old->tgcred->process_keyring); + new->process_keyring = key_get(old->process_keyring); security_transfer_creds(new, old); diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 66e21184b55..4bd6bdb7419 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -126,6 +126,7 @@ static int call_sbin_request_key(struct key_construction *cons, cred = get_current_cred(); keyring = keyring_alloc(desc, cred->fsuid, cred->fsgid, cred, + KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ, KEY_ALLOC_QUOTA_OVERRUN, NULL); put_cred(cred); if (IS_ERR(keyring)) { @@ -150,12 +151,12 @@ static int call_sbin_request_key(struct key_construction *cons, cred->thread_keyring ? cred->thread_keyring->serial : 0); prkey = 0; - if (cred->tgcred->process_keyring) - prkey = cred->tgcred->process_keyring->serial; + if (cred->process_keyring) + prkey = cred->process_keyring->serial; sprintf(keyring_str[1], "%d", prkey); rcu_read_lock(); - session = rcu_dereference(cred->tgcred->session_keyring); + session = rcu_dereference(cred->session_keyring); if (!session) session = cred->user->session_keyring; sskey = session->serial; @@ -297,14 +298,14 @@ static void construct_get_dest_keyring(struct key **_dest_keyring) break; case KEY_REQKEY_DEFL_PROCESS_KEYRING: - dest_keyring = key_get(cred->tgcred->process_keyring); + dest_keyring = key_get(cred->process_keyring); if (dest_keyring) break; case KEY_REQKEY_DEFL_SESSION_KEYRING: rcu_read_lock(); dest_keyring = key_get( - rcu_dereference(cred->tgcred->session_keyring)); + rcu_dereference(cred->session_keyring)); rcu_read_unlock(); if (dest_keyring) @@ -347,6 +348,7 @@ static int construct_alloc_key(struct key_type *type, const struct cred *cred = current_cred(); unsigned long prealloc; struct key *key; + key_perm_t perm; key_ref_t key_ref; int ret; @@ -355,8 +357,15 @@ static int construct_alloc_key(struct key_type *type, *_key = NULL; mutex_lock(&user->cons_lock); + perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; + perm |= KEY_USR_VIEW; + if (type->read) + perm |= KEY_POS_READ; + if (type == &key_type_keyring || type->update) + perm |= KEY_POS_WRITE; + key = key_alloc(type, description, cred->fsuid, cred->fsgid, cred, - KEY_POS_ALL, flags); + perm, flags); if (IS_ERR(key)) goto alloc_failed; |