1117 lines
30 KiB
C
1117 lines
30 KiB
C
/*
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* AppArmor security module
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*
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* This file contains AppArmor policy manipulation functions
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*
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* Copyright (C) 1998-2008 Novell/SUSE
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* Copyright 2009-2010 Canonical Ltd.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, version 2 of the
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* License.
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*
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*
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* AppArmor policy is based around profiles, which contain the rules a
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* task is confined by. Every task in the system has a profile attached
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* to it determined either by matching "unconfined" tasks against the
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* visible set of profiles or by following a profiles attachment rules.
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*
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* Each profile exists in a profile namespace which is a container of
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* visible profiles. Each namespace contains a special "unconfined" profile,
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* which doesn't enforce any confinement on a task beyond DAC.
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*
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* Namespace and profile names can be written together in either
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* of two syntaxes.
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* :namespace:profile - used by kernel interfaces for easy detection
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* namespace://profile - used by policy
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*
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* Profile names can not start with : or @ or ^ and may not contain \0
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*
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* Reserved profile names
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* unconfined - special automatically generated unconfined profile
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* inherit - special name to indicate profile inheritance
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* null-XXXX-YYYY - special automatically generated learning profiles
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*
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* Namespace names may not start with / or @ and may not contain \0 or :
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* Reserved namespace names
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* user-XXXX - user defined profiles
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*
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* a // in a profile or namespace name indicates a hierarchical name with the
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* name before the // being the parent and the name after the child.
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*
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* Profile and namespace hierarchies serve two different but similar purposes.
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* The namespace contains the set of visible profiles that are considered
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* for attachment. The hierarchy of namespaces allows for virtualizing
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* the namespace so that for example a chroot can have its own set of profiles
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* which may define some local user namespaces.
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* The profile hierarchy severs two distinct purposes,
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* - it allows for sub profiles or hats, which allows an application to run
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* subprograms under its own profile with different restriction than it
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* self, and not have it use the system profile.
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* eg. if a mail program starts an editor, the policy might make the
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* restrictions tighter on the editor tighter than the mail program,
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* and definitely different than general editor restrictions
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* - it allows for binary hierarchy of profiles, so that execution history
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* is preserved. This feature isn't exploited by AppArmor reference policy
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* but is allowed. NOTE: this is currently suboptimal because profile
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* aliasing is not currently implemented so that a profile for each
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* level must be defined.
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* eg. /bin/bash///bin/ls as a name would indicate /bin/ls was started
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* from /bin/bash
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*
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* A profile or namespace name that can contain one or more // separators
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* is referred to as an hname (hierarchical).
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* eg. /bin/bash//bin/ls
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*
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* An fqname is a name that may contain both namespace and profile hnames.
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* eg. :ns:/bin/bash//bin/ls
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*
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* NOTES:
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* - locking of profile lists is currently fairly coarse. All profile
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* lists within a namespace use the namespace lock.
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* FIXME: move profile lists to using rcu_lists
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*/
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/string.h>
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#include <linux/cred.h>
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#include <linux/rculist.h>
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#include <linux/user_namespace.h>
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#include "include/apparmor.h"
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#include "include/capability.h"
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#include "include/context.h"
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#include "include/file.h"
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#include "include/ipc.h"
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#include "include/match.h"
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#include "include/path.h"
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#include "include/policy.h"
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#include "include/policy_ns.h"
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#include "include/policy_unpack.h"
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#include "include/resource.h"
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int unprivileged_userns_apparmor_policy = 1;
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const char *const aa_profile_mode_names[] = {
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"enforce",
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"complain",
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"kill",
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"unconfined",
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};
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/* requires profile list write lock held */
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void __aa_update_proxy(struct aa_profile *orig, struct aa_profile *new)
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{
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struct aa_profile *tmp;
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tmp = rcu_dereference_protected(orig->proxy->profile,
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mutex_is_locked(&orig->ns->lock));
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rcu_assign_pointer(orig->proxy->profile, aa_get_profile(new));
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orig->flags |= PFLAG_STALE;
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aa_put_profile(tmp);
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}
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/**
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* __list_add_profile - add a profile to a list
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* @list: list to add it to (NOT NULL)
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* @profile: the profile to add (NOT NULL)
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*
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* refcount @profile, should be put by __list_remove_profile
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*
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* Requires: namespace lock be held, or list not be shared
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*/
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static void __list_add_profile(struct list_head *list,
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struct aa_profile *profile)
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{
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list_add_rcu(&profile->base.list, list);
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/* get list reference */
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aa_get_profile(profile);
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}
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/**
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* __list_remove_profile - remove a profile from the list it is on
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* @profile: the profile to remove (NOT NULL)
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*
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* remove a profile from the list, warning generally removal should
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* be done with __replace_profile as most profile removals are
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* replacements to the unconfined profile.
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*
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* put @profile list refcount
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*
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* Requires: namespace lock be held, or list not have been live
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*/
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static void __list_remove_profile(struct aa_profile *profile)
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{
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list_del_rcu(&profile->base.list);
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aa_put_profile(profile);
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}
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/**
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* __remove_profile - remove old profile, and children
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* @profile: profile to be replaced (NOT NULL)
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*
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* Requires: namespace list lock be held, or list not be shared
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*/
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static void __remove_profile(struct aa_profile *profile)
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{
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/* release any children lists first */
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__aa_profile_list_release(&profile->base.profiles);
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/* released by free_profile */
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__aa_update_proxy(profile, profile->ns->unconfined);
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__aa_fs_profile_rmdir(profile);
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__list_remove_profile(profile);
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}
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/**
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* __aa_profile_list_release - remove all profiles on the list and put refs
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* @head: list of profiles (NOT NULL)
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*
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* Requires: namespace lock be held
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*/
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void __aa_profile_list_release(struct list_head *head)
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{
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struct aa_profile *profile, *tmp;
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list_for_each_entry_safe(profile, tmp, head, base.list)
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__remove_profile(profile);
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}
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static void free_proxy(struct aa_proxy *p)
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{
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if (p) {
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/* r->profile will not be updated any more as r is dead */
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aa_put_profile(rcu_dereference_protected(p->profile, true));
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kzfree(p);
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}
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}
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void aa_free_proxy_kref(struct kref *kref)
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{
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struct aa_proxy *p = container_of(kref, struct aa_proxy, count);
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free_proxy(p);
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}
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/**
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* aa_free_data - free a data blob
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* @ptr: data to free
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* @arg: unused
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*/
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static void aa_free_data(void *ptr, void *arg)
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{
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struct aa_data *data = ptr;
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kzfree(data->data);
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kzfree(data->key);
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kzfree(data);
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}
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/**
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* aa_free_profile - free a profile
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* @profile: the profile to free (MAYBE NULL)
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*
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* Free a profile, its hats and null_profile. All references to the profile,
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* its hats and null_profile must have been put.
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*
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* If the profile was referenced from a task context, free_profile() will
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* be called from an rcu callback routine, so we must not sleep here.
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*/
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void aa_free_profile(struct aa_profile *profile)
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{
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struct rhashtable *rht;
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AA_DEBUG("%s(%p)\n", __func__, profile);
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if (!profile)
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return;
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/* free children profiles */
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aa_policy_destroy(&profile->base);
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aa_put_profile(rcu_access_pointer(profile->parent));
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aa_put_ns(profile->ns);
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kzfree(profile->rename);
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aa_free_file_rules(&profile->file);
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aa_free_cap_rules(&profile->caps);
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aa_free_rlimit_rules(&profile->rlimits);
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kzfree(profile->dirname);
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aa_put_dfa(profile->xmatch);
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aa_put_dfa(profile->policy.dfa);
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aa_put_proxy(profile->proxy);
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if (profile->data) {
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rht = profile->data;
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profile->data = NULL;
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rhashtable_free_and_destroy(rht, aa_free_data, NULL);
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kzfree(rht);
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}
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kzfree(profile->hash);
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aa_put_loaddata(profile->rawdata);
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kzfree(profile);
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}
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/**
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* aa_free_profile_rcu - free aa_profile by rcu (called by aa_free_profile_kref)
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* @head: rcu_head callback for freeing of a profile (NOT NULL)
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*/
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static void aa_free_profile_rcu(struct rcu_head *head)
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{
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struct aa_profile *p = container_of(head, struct aa_profile, rcu);
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if (p->flags & PFLAG_NS_COUNT)
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aa_free_ns(p->ns);
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else
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aa_free_profile(p);
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}
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/**
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* aa_free_profile_kref - free aa_profile by kref (called by aa_put_profile)
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* @kr: kref callback for freeing of a profile (NOT NULL)
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*/
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void aa_free_profile_kref(struct kref *kref)
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{
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struct aa_profile *p = container_of(kref, struct aa_profile, count);
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call_rcu(&p->rcu, aa_free_profile_rcu);
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}
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/**
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* aa_alloc_profile - allocate, initialize and return a new profile
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* @hname: name of the profile (NOT NULL)
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* @gfp: allocation type
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*
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* Returns: refcount profile or NULL on failure
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*/
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struct aa_profile *aa_alloc_profile(const char *hname, gfp_t gfp)
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{
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struct aa_profile *profile;
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/* freed by free_profile - usually through aa_put_profile */
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profile = kzalloc(sizeof(*profile), gfp);
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if (!profile)
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return NULL;
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profile->proxy = kzalloc(sizeof(struct aa_proxy), gfp);
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if (!profile->proxy)
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goto fail;
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kref_init(&profile->proxy->count);
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if (!aa_policy_init(&profile->base, NULL, hname, gfp))
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goto fail;
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kref_init(&profile->count);
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/* refcount released by caller */
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return profile;
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fail:
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kzfree(profile->proxy);
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kzfree(profile);
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return NULL;
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}
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/**
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* aa_new_null_profile - create or find a null-X learning profile
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* @parent: profile that caused this profile to be created (NOT NULL)
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* @hat: true if the null- learning profile is a hat
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* @base: name to base the null profile off of
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* @gfp: type of allocation
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*
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* Find/Create a null- complain mode profile used in learning mode. The
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* name of the profile is unique and follows the format of parent//null-XXX.
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* where XXX is based on the @name or if that fails or is not supplied
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* a unique number
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*
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* null profiles are added to the profile list but the list does not
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* hold a count on them so that they are automatically released when
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* not in use.
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*
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* Returns: new refcounted profile else NULL on failure
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*/
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struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
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const char *base, gfp_t gfp)
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{
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struct aa_profile *profile;
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char *name;
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AA_BUG(!parent);
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if (base) {
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name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
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gfp);
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if (name) {
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sprintf(name, "%s//null-%s", parent->base.hname, base);
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goto name;
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}
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/* fall through to try shorter uniq */
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}
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name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
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if (!name)
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return NULL;
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sprintf(name, "%s//null-%x", parent->base.hname,
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atomic_inc_return(&parent->ns->uniq_null));
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name:
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/* lookup to see if this is a dup creation */
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profile = aa_find_child(parent, basename(name));
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if (profile)
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goto out;
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profile = aa_alloc_profile(name, gfp);
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if (!profile)
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goto fail;
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profile->mode = APPARMOR_COMPLAIN;
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profile->flags |= PFLAG_NULL;
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if (hat)
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profile->flags |= PFLAG_HAT;
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profile->path_flags = parent->path_flags;
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/* released on free_profile */
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rcu_assign_pointer(profile->parent, aa_get_profile(parent));
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profile->ns = aa_get_ns(parent->ns);
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profile->file.dfa = aa_get_dfa(nulldfa);
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profile->policy.dfa = aa_get_dfa(nulldfa);
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mutex_lock(&profile->ns->lock);
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__list_add_profile(&parent->base.profiles, profile);
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mutex_unlock(&profile->ns->lock);
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/* refcount released by caller */
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out:
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kfree(name);
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return profile;
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fail:
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kfree(name);
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aa_free_profile(profile);
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return NULL;
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}
|
|
|
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/* TODO: profile accounting - setup in remove */
|
|
|
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/**
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* __find_child - find a profile on @head list with a name matching @name
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* @head: list to search (NOT NULL)
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* @name: name of profile (NOT NULL)
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*
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* Requires: rcu_read_lock be held
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*
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* Returns: unrefcounted profile ptr, or NULL if not found
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*/
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static struct aa_profile *__find_child(struct list_head *head, const char *name)
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{
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return (struct aa_profile *)__policy_find(head, name);
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}
|
|
|
|
/**
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* __strn_find_child - find a profile on @head list using substring of @name
|
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* @head: list to search (NOT NULL)
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* @name: name of profile (NOT NULL)
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* @len: length of @name substring to match
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*
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* Requires: rcu_read_lock be held
|
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*
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* Returns: unrefcounted profile ptr, or NULL if not found
|
|
*/
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static struct aa_profile *__strn_find_child(struct list_head *head,
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const char *name, int len)
|
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{
|
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return (struct aa_profile *)__policy_strn_find(head, name, len);
|
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}
|
|
|
|
/**
|
|
* aa_find_child - find a profile by @name in @parent
|
|
* @parent: profile to search (NOT NULL)
|
|
* @name: profile name to search for (NOT NULL)
|
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*
|
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* Returns: a refcounted profile or NULL if not found
|
|
*/
|
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struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
|
|
{
|
|
struct aa_profile *profile;
|
|
|
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rcu_read_lock();
|
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do {
|
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profile = __find_child(&parent->base.profiles, name);
|
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} while (profile && !aa_get_profile_not0(profile));
|
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rcu_read_unlock();
|
|
|
|
/* refcount released by caller */
|
|
return profile;
|
|
}
|
|
|
|
/**
|
|
* __lookup_parent - lookup the parent of a profile of name @hname
|
|
* @ns: namespace to lookup profile in (NOT NULL)
|
|
* @hname: hierarchical profile name to find parent of (NOT NULL)
|
|
*
|
|
* Lookups up the parent of a fully qualified profile name, the profile
|
|
* that matches hname does not need to exist, in general this
|
|
* is used to load a new profile.
|
|
*
|
|
* Requires: rcu_read_lock be held
|
|
*
|
|
* Returns: unrefcounted policy or NULL if not found
|
|
*/
|
|
static struct aa_policy *__lookup_parent(struct aa_ns *ns,
|
|
const char *hname)
|
|
{
|
|
struct aa_policy *policy;
|
|
struct aa_profile *profile = NULL;
|
|
char *split;
|
|
|
|
policy = &ns->base;
|
|
|
|
for (split = strstr(hname, "//"); split;) {
|
|
profile = __strn_find_child(&policy->profiles, hname,
|
|
split - hname);
|
|
if (!profile)
|
|
return NULL;
|
|
policy = &profile->base;
|
|
hname = split + 2;
|
|
split = strstr(hname, "//");
|
|
}
|
|
if (!profile)
|
|
return &ns->base;
|
|
return &profile->base;
|
|
}
|
|
|
|
/**
|
|
* __lookupn_profile - lookup the profile matching @hname
|
|
* @base: base list to start looking up profile name from (NOT NULL)
|
|
* @hname: hierarchical profile name (NOT NULL)
|
|
* @n: length of @hname
|
|
*
|
|
* Requires: rcu_read_lock be held
|
|
*
|
|
* Returns: unrefcounted profile pointer or NULL if not found
|
|
*
|
|
* Do a relative name lookup, recursing through profile tree.
|
|
*/
|
|
static struct aa_profile *__lookupn_profile(struct aa_policy *base,
|
|
const char *hname, size_t n)
|
|
{
|
|
struct aa_profile *profile = NULL;
|
|
const char *split;
|
|
|
|
for (split = strnstr(hname, "//", n); split;
|
|
split = strnstr(hname, "//", n)) {
|
|
profile = __strn_find_child(&base->profiles, hname,
|
|
split - hname);
|
|
if (!profile)
|
|
return NULL;
|
|
|
|
base = &profile->base;
|
|
n -= split + 2 - hname;
|
|
hname = split + 2;
|
|
}
|
|
|
|
if (n)
|
|
return __strn_find_child(&base->profiles, hname, n);
|
|
return NULL;
|
|
}
|
|
|
|
static struct aa_profile *__lookup_profile(struct aa_policy *base,
|
|
const char *hname)
|
|
{
|
|
return __lookupn_profile(base, hname, strlen(hname));
|
|
}
|
|
|
|
/**
|
|
* aa_lookup_profile - find a profile by its full or partial name
|
|
* @ns: the namespace to start from (NOT NULL)
|
|
* @hname: name to do lookup on. Does not contain namespace prefix (NOT NULL)
|
|
* @n: size of @hname
|
|
*
|
|
* Returns: refcounted profile or NULL if not found
|
|
*/
|
|
struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
|
|
size_t n)
|
|
{
|
|
struct aa_profile *profile;
|
|
|
|
rcu_read_lock();
|
|
do {
|
|
profile = __lookupn_profile(&ns->base, hname, n);
|
|
} while (profile && !aa_get_profile_not0(profile));
|
|
rcu_read_unlock();
|
|
|
|
/* the unconfined profile is not in the regular profile list */
|
|
if (!profile && strncmp(hname, "unconfined", n) == 0)
|
|
profile = aa_get_newest_profile(ns->unconfined);
|
|
|
|
/* refcount released by caller */
|
|
return profile;
|
|
}
|
|
|
|
struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *hname)
|
|
{
|
|
return aa_lookupn_profile(ns, hname, strlen(hname));
|
|
}
|
|
|
|
struct aa_profile *aa_fqlookupn_profile(struct aa_profile *base,
|
|
const char *fqname, size_t n)
|
|
{
|
|
struct aa_profile *profile;
|
|
struct aa_ns *ns;
|
|
const char *name, *ns_name;
|
|
size_t ns_len;
|
|
|
|
name = aa_splitn_fqname(fqname, n, &ns_name, &ns_len);
|
|
if (ns_name) {
|
|
ns = aa_findn_ns(base->ns, ns_name, ns_len);
|
|
if (!ns)
|
|
return NULL;
|
|
} else
|
|
ns = aa_get_ns(base->ns);
|
|
|
|
if (name)
|
|
profile = aa_lookupn_profile(ns, name, n - (name - fqname));
|
|
else if (ns)
|
|
/* default profile for ns, currently unconfined */
|
|
profile = aa_get_newest_profile(ns->unconfined);
|
|
else
|
|
profile = NULL;
|
|
aa_put_ns(ns);
|
|
|
|
return profile;
|
|
}
|
|
|
|
/**
|
|
* replacement_allowed - test to see if replacement is allowed
|
|
* @profile: profile to test if it can be replaced (MAYBE NULL)
|
|
* @noreplace: true if replacement shouldn't be allowed but addition is okay
|
|
* @info: Returns - info about why replacement failed (NOT NULL)
|
|
*
|
|
* Returns: %0 if replacement allowed else error code
|
|
*/
|
|
static int replacement_allowed(struct aa_profile *profile, int noreplace,
|
|
const char **info)
|
|
{
|
|
if (profile) {
|
|
if (profile->flags & PFLAG_IMMUTABLE) {
|
|
*info = "cannot replace immutible profile";
|
|
return -EPERM;
|
|
} else if (noreplace) {
|
|
*info = "profile already exists";
|
|
return -EEXIST;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* audit callback for net specific fields */
|
|
static void audit_cb(struct audit_buffer *ab, void *va)
|
|
{
|
|
struct common_audit_data *sa = va;
|
|
|
|
if (aad(sa)->iface.ns) {
|
|
audit_log_format(ab, " ns=");
|
|
audit_log_untrustedstring(ab, aad(sa)->iface.ns);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* aa_audit_policy - Do auditing of policy changes
|
|
* @profile: profile to check if it can manage policy
|
|
* @op: policy operation being performed
|
|
* @gfp: memory allocation flags
|
|
* @nsname: name of the ns being manipulated (MAY BE NULL)
|
|
* @name: name of profile being manipulated (NOT NULL)
|
|
* @info: any extra information to be audited (MAYBE NULL)
|
|
* @error: error code
|
|
*
|
|
* Returns: the error to be returned after audit is done
|
|
*/
|
|
static int audit_policy(struct aa_profile *profile, const char *op,
|
|
const char *nsname, const char *name,
|
|
const char *info, int error)
|
|
{
|
|
DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, op);
|
|
|
|
aad(&sa)->iface.ns = nsname;
|
|
aad(&sa)->name = name;
|
|
aad(&sa)->info = info;
|
|
aad(&sa)->error = error;
|
|
|
|
return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
|
|
}
|
|
|
|
/**
|
|
* policy_view_capable - check if viewing policy in at @ns is allowed
|
|
* ns: namespace being viewed by current task (may be NULL)
|
|
* Returns: true if viewing policy is allowed
|
|
*
|
|
* If @ns is NULL then the namespace being viewed is assumed to be the
|
|
* tasks current namespace.
|
|
*/
|
|
bool policy_view_capable(struct aa_ns *ns)
|
|
{
|
|
struct user_namespace *user_ns = current_user_ns();
|
|
struct aa_ns *view_ns = aa_get_current_ns();
|
|
bool root_in_user_ns = uid_eq(current_euid(), make_kuid(user_ns, 0)) ||
|
|
in_egroup_p(make_kgid(user_ns, 0));
|
|
bool response = false;
|
|
if (!ns)
|
|
ns = view_ns;
|
|
|
|
if (root_in_user_ns && aa_ns_visible(view_ns, ns, true) &&
|
|
(user_ns == &init_user_ns ||
|
|
(unprivileged_userns_apparmor_policy != 0 &&
|
|
user_ns->level == view_ns->level)))
|
|
response = true;
|
|
aa_put_ns(view_ns);
|
|
|
|
return response;
|
|
}
|
|
|
|
bool policy_admin_capable(struct aa_ns *ns)
|
|
{
|
|
struct user_namespace *user_ns = current_user_ns();
|
|
bool capable = ns_capable(user_ns, CAP_MAC_ADMIN);
|
|
|
|
AA_DEBUG("cap_mac_admin? %d\n", capable);
|
|
AA_DEBUG("policy locked? %d\n", aa_g_lock_policy);
|
|
|
|
return policy_view_capable(ns) && capable && !aa_g_lock_policy;
|
|
}
|
|
|
|
/**
|
|
* aa_may_manage_policy - can the current task manage policy
|
|
* @profile: profile to check if it can manage policy
|
|
* @op: the policy manipulation operation being done
|
|
*
|
|
* Returns: 0 if the task is allowed to manipulate policy else error
|
|
*/
|
|
int aa_may_manage_policy(struct aa_profile *profile, struct aa_ns *ns,
|
|
const char *op)
|
|
{
|
|
/* check if loading policy is locked out */
|
|
if (aa_g_lock_policy)
|
|
return audit_policy(profile, op, NULL, NULL,
|
|
"policy_locked", -EACCES);
|
|
|
|
if (!policy_admin_capable(ns))
|
|
return audit_policy(profile, op, NULL, NULL,
|
|
"not policy admin", -EACCES);
|
|
|
|
/* TODO: add fine grained mediation of policy loads */
|
|
return 0;
|
|
}
|
|
|
|
static struct aa_profile *__list_lookup_parent(struct list_head *lh,
|
|
struct aa_profile *profile)
|
|
{
|
|
const char *base = basename(profile->base.hname);
|
|
long len = base - profile->base.hname;
|
|
struct aa_load_ent *ent;
|
|
|
|
/* parent won't have trailing // so remove from len */
|
|
if (len <= 2)
|
|
return NULL;
|
|
len -= 2;
|
|
|
|
list_for_each_entry(ent, lh, list) {
|
|
if (ent->new == profile)
|
|
continue;
|
|
if (strncmp(ent->new->base.hname, profile->base.hname, len) ==
|
|
0 && ent->new->base.hname[len] == 0)
|
|
return ent->new;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* __replace_profile - replace @old with @new on a list
|
|
* @old: profile to be replaced (NOT NULL)
|
|
* @new: profile to replace @old with (NOT NULL)
|
|
* @share_proxy: transfer @old->proxy to @new
|
|
*
|
|
* Will duplicate and refcount elements that @new inherits from @old
|
|
* and will inherit @old children.
|
|
*
|
|
* refcount @new for list, put @old list refcount
|
|
*
|
|
* Requires: namespace list lock be held, or list not be shared
|
|
*/
|
|
static void __replace_profile(struct aa_profile *old, struct aa_profile *new,
|
|
bool share_proxy)
|
|
{
|
|
struct aa_profile *child, *tmp;
|
|
|
|
if (!list_empty(&old->base.profiles)) {
|
|
LIST_HEAD(lh);
|
|
list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu);
|
|
|
|
list_for_each_entry_safe(child, tmp, &lh, base.list) {
|
|
struct aa_profile *p;
|
|
|
|
list_del_init(&child->base.list);
|
|
p = __find_child(&new->base.profiles, child->base.name);
|
|
if (p) {
|
|
/* @p replaces @child */
|
|
__replace_profile(child, p, share_proxy);
|
|
continue;
|
|
}
|
|
|
|
/* inherit @child and its children */
|
|
/* TODO: update hname of inherited children */
|
|
/* list refcount transferred to @new */
|
|
p = aa_deref_parent(child);
|
|
rcu_assign_pointer(child->parent, aa_get_profile(new));
|
|
list_add_rcu(&child->base.list, &new->base.profiles);
|
|
aa_put_profile(p);
|
|
}
|
|
}
|
|
|
|
if (!rcu_access_pointer(new->parent)) {
|
|
struct aa_profile *parent = aa_deref_parent(old);
|
|
rcu_assign_pointer(new->parent, aa_get_profile(parent));
|
|
}
|
|
__aa_update_proxy(old, new);
|
|
if (share_proxy) {
|
|
aa_put_proxy(new->proxy);
|
|
new->proxy = aa_get_proxy(old->proxy);
|
|
} else if (!rcu_access_pointer(new->proxy->profile))
|
|
/* aafs interface uses proxy */
|
|
rcu_assign_pointer(new->proxy->profile,
|
|
aa_get_profile(new));
|
|
__aa_fs_profile_migrate_dents(old, new);
|
|
|
|
if (list_empty(&new->base.list)) {
|
|
/* new is not on a list already */
|
|
list_replace_rcu(&old->base.list, &new->base.list);
|
|
aa_get_profile(new);
|
|
aa_put_profile(old);
|
|
} else
|
|
__list_remove_profile(old);
|
|
}
|
|
|
|
/**
|
|
* __lookup_replace - lookup replacement information for a profile
|
|
* @ns - namespace the lookup occurs in
|
|
* @hname - name of profile to lookup
|
|
* @noreplace - true if not replacing an existing profile
|
|
* @p - Returns: profile to be replaced
|
|
* @info - Returns: info string on why lookup failed
|
|
*
|
|
* Returns: profile to replace (no ref) on success else ptr error
|
|
*/
|
|
static int __lookup_replace(struct aa_ns *ns, const char *hname,
|
|
bool noreplace, struct aa_profile **p,
|
|
const char **info)
|
|
{
|
|
*p = aa_get_profile(__lookup_profile(&ns->base, hname));
|
|
if (*p) {
|
|
int error = replacement_allowed(*p, noreplace, info);
|
|
if (error) {
|
|
*info = "profile can not be replaced";
|
|
return error;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* aa_replace_profiles - replace profile(s) on the profile list
|
|
* @view: namespace load is viewed from
|
|
* @label: label that is attempting to load/replace policy
|
|
* @noreplace: true if only doing addition, no replacement allowed
|
|
* @udata: serialized data stream (NOT NULL)
|
|
*
|
|
* unpack and replace a profile on the profile list and uses of that profile
|
|
* by any aa_task_ctx. If the profile does not exist on the profile list
|
|
* it is added.
|
|
*
|
|
* Returns: size of data consumed else error code on failure.
|
|
*/
|
|
ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
|
|
bool noreplace, struct aa_loaddata *udata)
|
|
{
|
|
const char *ns_name, *info = NULL;
|
|
struct aa_ns *ns = NULL;
|
|
struct aa_load_ent *ent, *tmp;
|
|
const char *op = OP_PROF_REPL;
|
|
ssize_t count, error;
|
|
LIST_HEAD(lh);
|
|
|
|
/* released below */
|
|
error = aa_unpack(udata, &lh, &ns_name);
|
|
if (error)
|
|
goto out;
|
|
|
|
/* ensure that profiles are all for the same ns
|
|
* TODO: update locking to remove this constaint. All profiles in
|
|
* the load set must succeed as a set or the load will
|
|
* fail. Sort ent list and take ns locks in hierarchy order
|
|
*/
|
|
count = 0;
|
|
list_for_each_entry(ent, &lh, list) {
|
|
if (ns_name) {
|
|
if (ent->ns_name &&
|
|
strcmp(ent->ns_name, ns_name) != 0) {
|
|
info = "policy load has mixed namespaces";
|
|
error = -EACCES;
|
|
goto fail;
|
|
}
|
|
} else if (ent->ns_name) {
|
|
if (count) {
|
|
info = "policy load has mixed namespaces";
|
|
error = -EACCES;
|
|
goto fail;
|
|
}
|
|
ns_name = ent->ns_name;
|
|
} else
|
|
count++;
|
|
}
|
|
if (ns_name) {
|
|
ns = aa_prepare_ns(view, ns_name);
|
|
if (IS_ERR(ns)) {
|
|
info = "failed to prepare namespace";
|
|
error = PTR_ERR(ns);
|
|
ns = NULL;
|
|
goto fail;
|
|
}
|
|
} else
|
|
ns = aa_get_ns(view);
|
|
|
|
mutex_lock(&ns->lock);
|
|
/* setup parent and ns info */
|
|
list_for_each_entry(ent, &lh, list) {
|
|
struct aa_policy *policy;
|
|
ent->new->rawdata = aa_get_loaddata(udata);
|
|
error = __lookup_replace(ns, ent->new->base.hname, noreplace,
|
|
&ent->old, &info);
|
|
if (error)
|
|
goto fail_lock;
|
|
|
|
if (ent->new->rename) {
|
|
error = __lookup_replace(ns, ent->new->rename,
|
|
noreplace, &ent->rename,
|
|
&info);
|
|
if (error)
|
|
goto fail_lock;
|
|
}
|
|
|
|
/* released when @new is freed */
|
|
ent->new->ns = aa_get_ns(ns);
|
|
|
|
if (ent->old || ent->rename)
|
|
continue;
|
|
|
|
/* no ref on policy only use inside lock */
|
|
policy = __lookup_parent(ns, ent->new->base.hname);
|
|
if (!policy) {
|
|
struct aa_profile *p;
|
|
p = __list_lookup_parent(&lh, ent->new);
|
|
if (!p) {
|
|
error = -ENOENT;
|
|
info = "parent does not exist";
|
|
goto fail_lock;
|
|
}
|
|
rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
|
|
} else if (policy != &ns->base) {
|
|
/* released on profile replacement or free_profile */
|
|
struct aa_profile *p = (struct aa_profile *) policy;
|
|
rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
|
|
}
|
|
}
|
|
|
|
/* create new fs entries for introspection if needed */
|
|
list_for_each_entry(ent, &lh, list) {
|
|
if (ent->old) {
|
|
/* inherit old interface files */
|
|
|
|
/* if (ent->rename)
|
|
TODO: support rename */
|
|
/* } else if (ent->rename) {
|
|
TODO: support rename */
|
|
} else {
|
|
struct dentry *parent;
|
|
if (rcu_access_pointer(ent->new->parent)) {
|
|
struct aa_profile *p;
|
|
p = aa_deref_parent(ent->new);
|
|
parent = prof_child_dir(p);
|
|
} else
|
|
parent = ns_subprofs_dir(ent->new->ns);
|
|
error = __aa_fs_profile_mkdir(ent->new, parent);
|
|
}
|
|
|
|
if (error) {
|
|
info = "failed to create ";
|
|
goto fail_lock;
|
|
}
|
|
}
|
|
|
|
/* Done with checks that may fail - do actual replacement */
|
|
list_for_each_entry_safe(ent, tmp, &lh, list) {
|
|
list_del_init(&ent->list);
|
|
op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
|
|
|
|
audit_policy(profile, op, NULL, ent->new->base.hname,
|
|
NULL, error);
|
|
|
|
if (ent->old) {
|
|
__replace_profile(ent->old, ent->new, 1);
|
|
if (ent->rename) {
|
|
/* aafs interface uses proxy */
|
|
struct aa_proxy *r = ent->new->proxy;
|
|
rcu_assign_pointer(r->profile,
|
|
aa_get_profile(ent->new));
|
|
__replace_profile(ent->rename, ent->new, 0);
|
|
}
|
|
} else if (ent->rename) {
|
|
/* aafs interface uses proxy */
|
|
rcu_assign_pointer(ent->new->proxy->profile,
|
|
aa_get_profile(ent->new));
|
|
__replace_profile(ent->rename, ent->new, 0);
|
|
} else if (ent->new->parent) {
|
|
struct aa_profile *parent, *newest;
|
|
parent = aa_deref_parent(ent->new);
|
|
newest = aa_get_newest_profile(parent);
|
|
|
|
/* parent replaced in this atomic set? */
|
|
if (newest != parent) {
|
|
aa_get_profile(newest);
|
|
rcu_assign_pointer(ent->new->parent, newest);
|
|
aa_put_profile(parent);
|
|
}
|
|
/* aafs interface uses proxy */
|
|
rcu_assign_pointer(ent->new->proxy->profile,
|
|
aa_get_profile(ent->new));
|
|
__list_add_profile(&newest->base.profiles, ent->new);
|
|
aa_put_profile(newest);
|
|
} else {
|
|
/* aafs interface uses proxy */
|
|
rcu_assign_pointer(ent->new->proxy->profile,
|
|
aa_get_profile(ent->new));
|
|
__list_add_profile(&ns->base.profiles, ent->new);
|
|
}
|
|
aa_load_ent_free(ent);
|
|
}
|
|
mutex_unlock(&ns->lock);
|
|
|
|
out:
|
|
aa_put_ns(ns);
|
|
|
|
if (error)
|
|
return error;
|
|
return udata->size;
|
|
|
|
fail_lock:
|
|
mutex_unlock(&ns->lock);
|
|
|
|
/* audit cause of failure */
|
|
op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
|
|
fail:
|
|
audit_policy(profile, op, ns_name, ent->new->base.hname,
|
|
info, error);
|
|
/* audit status that rest of profiles in the atomic set failed too */
|
|
info = "valid profile in failed atomic policy load";
|
|
list_for_each_entry(tmp, &lh, list) {
|
|
if (tmp == ent) {
|
|
info = "unchecked profile in failed atomic policy load";
|
|
/* skip entry that caused failure */
|
|
continue;
|
|
}
|
|
op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
|
|
audit_policy(profile, op, ns_name,
|
|
tmp->new->base.hname, info, error);
|
|
}
|
|
list_for_each_entry_safe(ent, tmp, &lh, list) {
|
|
list_del_init(&ent->list);
|
|
aa_load_ent_free(ent);
|
|
}
|
|
|
|
goto out;
|
|
}
|
|
|
|
/**
|
|
* aa_remove_profiles - remove profile(s) from the system
|
|
* @view: namespace the remove is being done from
|
|
* @subj: profile attempting to remove policy
|
|
* @fqname: name of the profile or namespace to remove (NOT NULL)
|
|
* @size: size of the name
|
|
*
|
|
* Remove a profile or sub namespace from the current namespace, so that
|
|
* they can not be found anymore and mark them as replaced by unconfined
|
|
*
|
|
* NOTE: removing confinement does not restore rlimits to preconfinemnet values
|
|
*
|
|
* Returns: size of data consume else error code if fails
|
|
*/
|
|
ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_profile *subj,
|
|
char *fqname, size_t size)
|
|
{
|
|
struct aa_ns *root = NULL, *ns = NULL;
|
|
struct aa_profile *profile = NULL;
|
|
const char *name = fqname, *info = NULL;
|
|
char *ns_name = NULL;
|
|
ssize_t error = 0;
|
|
|
|
if (*fqname == 0) {
|
|
info = "no profile specified";
|
|
error = -ENOENT;
|
|
goto fail;
|
|
}
|
|
|
|
root = view;
|
|
|
|
if (fqname[0] == ':') {
|
|
name = aa_split_fqname(fqname, &ns_name);
|
|
/* released below */
|
|
ns = aa_find_ns(root, ns_name);
|
|
if (!ns) {
|
|
info = "namespace does not exist";
|
|
error = -ENOENT;
|
|
goto fail;
|
|
}
|
|
} else
|
|
/* released below */
|
|
ns = aa_get_ns(root);
|
|
|
|
if (!name) {
|
|
/* remove namespace - can only happen if fqname[0] == ':' */
|
|
mutex_lock(&ns->parent->lock);
|
|
__aa_remove_ns(ns);
|
|
mutex_unlock(&ns->parent->lock);
|
|
} else {
|
|
/* remove profile */
|
|
mutex_lock(&ns->lock);
|
|
profile = aa_get_profile(__lookup_profile(&ns->base, name));
|
|
if (!profile) {
|
|
error = -ENOENT;
|
|
info = "profile does not exist";
|
|
goto fail_ns_lock;
|
|
}
|
|
name = profile->base.hname;
|
|
__remove_profile(profile);
|
|
mutex_unlock(&ns->lock);
|
|
}
|
|
|
|
/* don't fail removal if audit fails */
|
|
(void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
|
|
error);
|
|
aa_put_ns(ns);
|
|
aa_put_profile(profile);
|
|
return size;
|
|
|
|
fail_ns_lock:
|
|
mutex_unlock(&ns->lock);
|
|
aa_put_ns(ns);
|
|
|
|
fail:
|
|
(void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
|
|
error);
|
|
return error;
|
|
}
|