diff options
Diffstat (limited to 'security')
-rw-r--r-- | security/capability.c | 6 | ||||
-rw-r--r-- | security/commoncap.c | 25 | ||||
-rw-r--r-- | security/integrity/ima/ima.h | 2 | ||||
-rw-r--r-- | security/integrity/ima/ima_api.c | 4 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 21 | ||||
-rw-r--r-- | security/integrity/ima/ima_policy.c | 3 | ||||
-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 | ||||
-rw-r--r-- | security/security.c | 10 | ||||
-rw-r--r-- | security/smack/Kconfig | 6 | ||||
-rw-r--r-- | security/smack/smackfs.c | 17 | ||||
-rw-r--r-- | security/yama/yama_lsm.c | 100 |
15 files changed, 222 insertions, 116 deletions
diff --git a/security/capability.c b/security/capability.c index b14a30c234b..0fe5a026aef 100644 --- a/security/capability.c +++ b/security/capability.c @@ -395,6 +395,11 @@ static int cap_kernel_module_request(char *kmod_name) return 0; } +static int cap_kernel_module_from_file(struct file *file) +{ + return 0; +} + static int cap_task_setpgid(struct task_struct *p, pid_t pgid) { return 0; @@ -967,6 +972,7 @@ void __init security_fixup_ops(struct security_operations *ops) set_to_cap_if_null(ops, kernel_act_as); set_to_cap_if_null(ops, kernel_create_files_as); set_to_cap_if_null(ops, kernel_module_request); + set_to_cap_if_null(ops, kernel_module_from_file); set_to_cap_if_null(ops, task_fix_setuid); set_to_cap_if_null(ops, task_setpgid); set_to_cap_if_null(ops, task_getpgid); diff --git a/security/commoncap.c b/security/commoncap.c index 6dbae4650ab..7ee08c756d6 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -76,24 +76,33 @@ int cap_netlink_send(struct sock *sk, struct sk_buff *skb) int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, int cap, int audit) { - for (;;) { - /* The owner of the user namespace has all caps. */ - if (targ_ns != &init_user_ns && uid_eq(targ_ns->owner, cred->euid)) - return 0; + struct user_namespace *ns = targ_ns; + /* See if cred has the capability in the target user namespace + * by examining the target user namespace and all of the target + * user namespace's parents. + */ + for (;;) { /* Do we have the necessary capabilities? */ - if (targ_ns == cred->user_ns) + if (ns == cred->user_ns) return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; /* Have we tried all of the parent namespaces? */ - if (targ_ns == &init_user_ns) + if (ns == &init_user_ns) return -EPERM; + /* + * The owner of the user namespace in the parent of the + * user namespace has all caps. + */ + if ((ns->parent == cred->user_ns) && uid_eq(ns->owner, cred->euid)) + return 0; + /* - *If you have a capability in a parent user ns, then you have + * If you have a capability in a parent user ns, then you have * it over all children user namespaces as well. */ - targ_ns = targ_ns->parent; + ns = ns->parent; } /* We never get here */ diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 6ee8826662c..3b2adb794f1 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -127,7 +127,7 @@ struct integrity_iint_cache *integrity_iint_insert(struct inode *inode); struct integrity_iint_cache *integrity_iint_find(struct inode *inode); /* IMA policy related functions */ -enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK, POST_SETATTR }; +enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK, MODULE_CHECK, POST_SETATTR }; int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, int flags); diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index b356884fb3e..0cea3db2165 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -100,12 +100,12 @@ err_out: * ima_get_action - appraise & measure decision based on policy. * @inode: pointer to inode to measure * @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXECUTE) - * @function: calling function (FILE_CHECK, BPRM_CHECK, FILE_MMAP) + * @function: calling function (FILE_CHECK, BPRM_CHECK, FILE_MMAP, MODULE_CHECK) * * The policy is defined in terms of keypairs: * subj=, obj=, type=, func=, mask=, fsmagic= * subj,obj, and type: are LSM specific. - * func: FILE_CHECK | BPRM_CHECK | FILE_MMAP + * func: FILE_CHECK | BPRM_CHECK | FILE_MMAP | MODULE_CHECK * mask: contains the permission mask * fsmagic: hex value * diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 73c9a268253..45de18e9a6f 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -280,6 +280,27 @@ int ima_file_check(struct file *file, int mask) } EXPORT_SYMBOL_GPL(ima_file_check); +/** + * ima_module_check - based on policy, collect/store/appraise measurement. + * @file: pointer to the file to be measured/appraised + * + * Measure/appraise kernel modules based on policy. + * + * Always return 0 and audit dentry_open failures. + * Return code is based upon measurement appraisal. + */ +int ima_module_check(struct file *file) +{ + int rc; + + if (!file) + rc = INTEGRITY_UNKNOWN; + else + rc = process_measurement(file, file->f_dentry->d_name.name, + MAY_EXEC, MODULE_CHECK); + return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0; +} + static int __init init_ima(void) { int error; diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index c7dacd2eab7..af7d182d5a4 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -80,6 +80,7 @@ static struct ima_rule_entry default_rules[] = { .flags = IMA_FUNC | IMA_MASK}, {.action = MEASURE,.func = FILE_CHECK,.mask = MAY_READ,.uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_MASK | IMA_UID}, + {.action = MEASURE,.func = MODULE_CHECK, .flags = IMA_FUNC}, }; static struct ima_rule_entry default_appraise_rules[] = { @@ -401,6 +402,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) /* PATH_CHECK is for backwards compat */ else if (strcmp(args[0].from, "PATH_CHECK") == 0) entry->func = FILE_CHECK; + else if (strcmp(args[0].from, "MODULE_CHECK") == 0) + entry->func = MODULE_CHECK; else if (strcmp(args[0].from, "FILE_MMAP") == 0) entry->func = FILE_MMAP; else if (strcmp(args[0].from, "BPRM_CHECK") == 0) 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; diff --git a/security/security.c b/security/security.c index 8dcd4ae10a5..daa97f4ac9d 100644 --- a/security/security.c +++ b/security/security.c @@ -820,6 +820,16 @@ int security_kernel_module_request(char *kmod_name) return security_ops->kernel_module_request(kmod_name); } +int security_kernel_module_from_file(struct file *file) +{ + int ret; + + ret = security_ops->kernel_module_from_file(file); + if (ret) + return ret; + return ima_module_check(file); +} + int security_task_fix_setuid(struct cred *new, const struct cred *old, int flags) { diff --git a/security/smack/Kconfig b/security/smack/Kconfig index 603b0878434..e69de9c642b 100644 --- a/security/smack/Kconfig +++ b/security/smack/Kconfig @@ -1,6 +1,10 @@ config SECURITY_SMACK bool "Simplified Mandatory Access Control Kernel Support" - depends on NETLABEL && SECURITY_NETWORK + depends on NET + depends on INET + depends on SECURITY + select NETLABEL + select SECURITY_NETWORK default n help This selects the Simplified Mandatory Access Control Kernel. diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 99929a50093..76a5dca4640 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -2063,6 +2063,19 @@ static const struct file_operations smk_revoke_subj_ops = { .llseek = generic_file_llseek, }; +static struct kset *smackfs_kset; +/** + * smk_init_sysfs - initialize /sys/fs/smackfs + * + */ +static int smk_init_sysfs(void) +{ + smackfs_kset = kset_create_and_add("smackfs", NULL, fs_kobj); + if (!smackfs_kset) + return -ENOMEM; + return 0; +} + /** * smk_fill_super - fill the /smackfs superblock * @sb: the empty superblock @@ -2183,6 +2196,10 @@ static int __init init_smk_fs(void) if (!security_module_enable(&smack_ops)) return 0; + err = smk_init_sysfs(); + if (err) + printk(KERN_ERR "smackfs: sysfs mountpoint problem.\n"); + err = register_filesystem(&smk_fs_type); if (!err) { smackfs_mount = kern_mount(&smk_fs_type); diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c index b4c29848b49..23414b93771 100644 --- a/security/yama/yama_lsm.c +++ b/security/yama/yama_lsm.c @@ -17,6 +17,7 @@ #include <linux/ptrace.h> #include <linux/prctl.h> #include <linux/ratelimit.h> +#include <linux/workqueue.h> #define YAMA_SCOPE_DISABLED 0 #define YAMA_SCOPE_RELATIONAL 1 @@ -29,12 +30,37 @@ static int ptrace_scope = YAMA_SCOPE_RELATIONAL; struct ptrace_relation { struct task_struct *tracer; struct task_struct *tracee; + bool invalid; struct list_head node; + struct rcu_head rcu; }; static LIST_HEAD(ptracer_relations); static DEFINE_SPINLOCK(ptracer_relations_lock); +static void yama_relation_cleanup(struct work_struct *work); +static DECLARE_WORK(yama_relation_work, yama_relation_cleanup); + +/** + * yama_relation_cleanup - remove invalid entries from the relation list + * + */ +static void yama_relation_cleanup(struct work_struct *work) +{ + struct ptrace_relation *relation; + + spin_lock(&ptracer_relations_lock); + rcu_read_lock(); + list_for_each_entry_rcu(relation, &ptracer_relations, node) { + if (relation->invalid) { + list_del_rcu(&relation->node); + kfree_rcu(relation, rcu); + } + } + rcu_read_unlock(); + spin_unlock(&ptracer_relations_lock); +} + /** * yama_ptracer_add - add/replace an exception for this tracer/tracee pair * @tracer: the task_struct of the process doing the ptrace @@ -48,32 +74,34 @@ static DEFINE_SPINLOCK(ptracer_relations_lock); static int yama_ptracer_add(struct task_struct *tracer, struct task_struct *tracee) { - int rc = 0; - struct ptrace_relation *added; - struct ptrace_relation *entry, *relation = NULL; + struct ptrace_relation *relation, *added; added = kmalloc(sizeof(*added), GFP_KERNEL); if (!added) return -ENOMEM; - spin_lock_bh(&ptracer_relations_lock); - list_for_each_entry(entry, &ptracer_relations, node) - if (entry->tracee == tracee) { - relation = entry; - break; + added->tracee = tracee; + added->tracer = tracer; + added->invalid = false; + + spin_lock(&ptracer_relations_lock); + rcu_read_lock(); + list_for_each_entry_rcu(relation, &ptracer_relations, node) { + if (relation->invalid) + continue; + if (relation->tracee == tracee) { + list_replace_rcu(&relation->node, &added->node); + kfree_rcu(relation, rcu); + goto out; } - if (!relation) { - relation = added; - relation->tracee = tracee; - list_add(&relation->node, &ptracer_relations); } - relation->tracer = tracer; - spin_unlock_bh(&ptracer_relations_lock); - if (added != relation) - kfree(added); + list_add_rcu(&added->node, &ptracer_relations); - return rc; +out: + rcu_read_unlock(); + spin_unlock(&ptracer_relations_lock); + return 0; } /** @@ -84,16 +112,23 @@ static int yama_ptracer_add(struct task_struct *tracer, static void yama_ptracer_del(struct task_struct *tracer, struct task_struct *tracee) { - struct ptrace_relation *relation, *safe; + struct ptrace_relation *relation; + bool marked = false; - spin_lock_bh(&ptracer_relations_lock); - list_for_each_entry_safe(relation, safe, &ptracer_relations, node) + rcu_read_lock(); + list_for_each_entry_rcu(relation, &ptracer_relations, node) { + if (relation->invalid) + continue; if (relation->tracee == tracee || (tracer && relation->tracer == tracer)) { - list_del(&relation->node); - kfree(relation); + relation->invalid = true; + marked = true; } - spin_unlock_bh(&ptracer_relations_lock); + } + rcu_read_unlock(); + + if (marked) + schedule_work(&yama_relation_work); } /** @@ -217,21 +252,22 @@ static int ptracer_exception_found(struct task_struct *tracer, struct task_struct *parent = NULL; bool found = false; - spin_lock_bh(&ptracer_relations_lock); rcu_read_lock(); if (!thread_group_leader(tracee)) tracee = rcu_dereference(tracee->group_leader); - list_for_each_entry(relation, &ptracer_relations, node) + list_for_each_entry_rcu(relation, &ptracer_relations, node) { + if (relation->invalid) + continue; if (relation->tracee == tracee) { parent = relation->tracer; found = true; break; } + } if (found && (parent == NULL || task_is_descendant(parent, tracer))) rc = 1; rcu_read_unlock(); - spin_unlock_bh(&ptracer_relations_lock); return rc; } @@ -262,14 +298,18 @@ int yama_ptrace_access_check(struct task_struct *child, /* No additional restrictions. */ break; case YAMA_SCOPE_RELATIONAL: + rcu_read_lock(); if (!task_is_descendant(current, child) && !ptracer_exception_found(current, child) && - !ns_capable(task_user_ns(child), CAP_SYS_PTRACE)) + !ns_capable(__task_cred(child)->user_ns, CAP_SYS_PTRACE)) rc = -EPERM; + rcu_read_unlock(); break; case YAMA_SCOPE_CAPABILITY: - if (!ns_capable(task_user_ns(child), CAP_SYS_PTRACE)) + rcu_read_lock(); + if (!ns_capable(__task_cred(child)->user_ns, CAP_SYS_PTRACE)) rc = -EPERM; + rcu_read_unlock(); break; case YAMA_SCOPE_NO_ATTACH: default: @@ -307,8 +347,10 @@ int yama_ptrace_traceme(struct task_struct *parent) /* Only disallow PTRACE_TRACEME on more aggressive settings. */ switch (ptrace_scope) { case YAMA_SCOPE_CAPABILITY: - if (!ns_capable(task_user_ns(parent), CAP_SYS_PTRACE)) + rcu_read_lock(); + if (!ns_capable(__task_cred(parent)->user_ns, CAP_SYS_PTRACE)) rc = -EPERM; + rcu_read_unlock(); break; case YAMA_SCOPE_NO_ATTACH: rc = -EPERM; |