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-rw-r--r--security/apparmor/policy.c1209
1 files changed, 1209 insertions, 0 deletions
diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c
new file mode 100644
index 000000000..c7b84fb56
--- /dev/null
+++ b/security/apparmor/policy.c
@@ -0,0 +1,1209 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor policy manipulation functions
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ *
+ * AppArmor policy is based around profiles, which contain the rules a
+ * task is confined by. Every task in the system has a profile attached
+ * to it determined either by matching "unconfined" tasks against the
+ * visible set of profiles or by following a profiles attachment rules.
+ *
+ * Each profile exists in a profile namespace which is a container of
+ * visible profiles. Each namespace contains a special "unconfined" profile,
+ * which doesn't enforce any confinement on a task beyond DAC.
+ *
+ * Namespace and profile names can be written together in either
+ * of two syntaxes.
+ * :namespace:profile - used by kernel interfaces for easy detection
+ * namespace://profile - used by policy
+ *
+ * Profile names can not start with : or @ or ^ and may not contain \0
+ *
+ * Reserved profile names
+ * unconfined - special automatically generated unconfined profile
+ * inherit - special name to indicate profile inheritance
+ * null-XXXX-YYYY - special automatically generated learning profiles
+ *
+ * Namespace names may not start with / or @ and may not contain \0 or :
+ * Reserved namespace names
+ * user-XXXX - user defined profiles
+ *
+ * a // in a profile or namespace name indicates a hierarchical name with the
+ * name before the // being the parent and the name after the child.
+ *
+ * Profile and namespace hierarchies serve two different but similar purposes.
+ * The namespace contains the set of visible profiles that are considered
+ * for attachment. The hierarchy of namespaces allows for virtualizing
+ * the namespace so that for example a chroot can have its own set of profiles
+ * which may define some local user namespaces.
+ * The profile hierarchy severs two distinct purposes,
+ * - it allows for sub profiles or hats, which allows an application to run
+ * subprograms under its own profile with different restriction than it
+ * self, and not have it use the system profile.
+ * eg. if a mail program starts an editor, the policy might make the
+ * restrictions tighter on the editor tighter than the mail program,
+ * and definitely different than general editor restrictions
+ * - it allows for binary hierarchy of profiles, so that execution history
+ * is preserved. This feature isn't exploited by AppArmor reference policy
+ * but is allowed. NOTE: this is currently suboptimal because profile
+ * aliasing is not currently implemented so that a profile for each
+ * level must be defined.
+ * eg. /bin/bash///bin/ls as a name would indicate /bin/ls was started
+ * from /bin/bash
+ *
+ * A profile or namespace name that can contain one or more // separators
+ * is referred to as an hname (hierarchical).
+ * eg. /bin/bash//bin/ls
+ *
+ * An fqname is a name that may contain both namespace and profile hnames.
+ * eg. :ns:/bin/bash//bin/ls
+ *
+ * NOTES:
+ * - locking of profile lists is currently fairly coarse. All profile
+ * lists within a namespace use the namespace lock.
+ * FIXME: move profile lists to using rcu_lists
+ */
+
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/cred.h>
+#include <linux/rculist.h>
+#include <linux/user_namespace.h>
+
+#include "include/apparmor.h"
+#include "include/capability.h"
+#include "include/cred.h"
+#include "include/file.h"
+#include "include/ipc.h"
+#include "include/match.h"
+#include "include/path.h"
+#include "include/policy.h"
+#include "include/policy_ns.h"
+#include "include/policy_unpack.h"
+#include "include/resource.h"
+
+int unprivileged_userns_apparmor_policy = 1;
+
+const char *const aa_profile_mode_names[] = {
+ "enforce",
+ "complain",
+ "kill",
+ "unconfined",
+};
+
+
+/**
+ * __add_profile - add a profiles to list and label tree
+ * @list: list to add it to (NOT NULL)
+ * @profile: the profile to add (NOT NULL)
+ *
+ * refcount @profile, should be put by __list_remove_profile
+ *
+ * Requires: namespace lock be held, or list not be shared
+ */
+static void __add_profile(struct list_head *list, struct aa_profile *profile)
+{
+ struct aa_label *l;
+
+ AA_BUG(!list);
+ AA_BUG(!profile);
+ AA_BUG(!profile->ns);
+ AA_BUG(!mutex_is_locked(&profile->ns->lock));
+
+ list_add_rcu(&profile->base.list, list);
+ /* get list reference */
+ aa_get_profile(profile);
+ l = aa_label_insert(&profile->ns->labels, &profile->label);
+ AA_BUG(l != &profile->label);
+ aa_put_label(l);
+}
+
+/**
+ * __list_remove_profile - remove a profile from the list it is on
+ * @profile: the profile to remove (NOT NULL)
+ *
+ * remove a profile from the list, warning generally removal should
+ * be done with __replace_profile as most profile removals are
+ * replacements to the unconfined profile.
+ *
+ * put @profile list refcount
+ *
+ * Requires: namespace lock be held, or list not have been live
+ */
+static void __list_remove_profile(struct aa_profile *profile)
+{
+ AA_BUG(!profile);
+ AA_BUG(!profile->ns);
+ AA_BUG(!mutex_is_locked(&profile->ns->lock));
+
+ list_del_rcu(&profile->base.list);
+ aa_put_profile(profile);
+}
+
+/**
+ * __remove_profile - remove old profile, and children
+ * @profile: profile to be replaced (NOT NULL)
+ *
+ * Requires: namespace list lock be held, or list not be shared
+ */
+static void __remove_profile(struct aa_profile *profile)
+{
+ AA_BUG(!profile);
+ AA_BUG(!profile->ns);
+ AA_BUG(!mutex_is_locked(&profile->ns->lock));
+
+ /* release any children lists first */
+ __aa_profile_list_release(&profile->base.profiles);
+ /* released by free_profile */
+ aa_label_remove(&profile->label);
+ __aafs_profile_rmdir(profile);
+ __list_remove_profile(profile);
+}
+
+/**
+ * __aa_profile_list_release - remove all profiles on the list and put refs
+ * @head: list of profiles (NOT NULL)
+ *
+ * Requires: namespace lock be held
+ */
+void __aa_profile_list_release(struct list_head *head)
+{
+ struct aa_profile *profile, *tmp;
+ list_for_each_entry_safe(profile, tmp, head, base.list)
+ __remove_profile(profile);
+}
+
+/**
+ * aa_free_data - free a data blob
+ * @ptr: data to free
+ * @arg: unused
+ */
+static void aa_free_data(void *ptr, void *arg)
+{
+ struct aa_data *data = ptr;
+
+ kfree_sensitive(data->data);
+ kfree_sensitive(data->key);
+ kfree_sensitive(data);
+}
+
+/**
+ * aa_free_profile - free a profile
+ * @profile: the profile to free (MAYBE NULL)
+ *
+ * Free a profile, its hats and null_profile. All references to the profile,
+ * its hats and null_profile must have been put.
+ *
+ * If the profile was referenced from a task context, free_profile() will
+ * be called from an rcu callback routine, so we must not sleep here.
+ */
+void aa_free_profile(struct aa_profile *profile)
+{
+ struct rhashtable *rht;
+ int i;
+
+ AA_DEBUG("%s(%p)\n", __func__, profile);
+
+ if (!profile)
+ return;
+
+ /* free children profiles */
+ aa_policy_destroy(&profile->base);
+ aa_put_profile(rcu_access_pointer(profile->parent));
+
+ aa_put_ns(profile->ns);
+ kfree_sensitive(profile->rename);
+ kfree_sensitive(profile->disconnected);
+
+ aa_free_file_rules(&profile->file);
+ aa_free_cap_rules(&profile->caps);
+ aa_free_rlimit_rules(&profile->rlimits);
+
+ for (i = 0; i < profile->xattr_count; i++)
+ kfree_sensitive(profile->xattrs[i]);
+ kfree_sensitive(profile->xattrs);
+ for (i = 0; i < profile->secmark_count; i++)
+ kfree_sensitive(profile->secmark[i].label);
+ kfree_sensitive(profile->secmark);
+ kfree_sensitive(profile->dirname);
+ aa_put_dfa(profile->xmatch);
+ aa_put_dfa(profile->policy.dfa);
+
+ if (profile->data) {
+ rht = profile->data;
+ profile->data = NULL;
+ rhashtable_free_and_destroy(rht, aa_free_data, NULL);
+ kfree_sensitive(rht);
+ }
+
+ kfree_sensitive(profile->hash);
+ aa_put_loaddata(profile->rawdata);
+ aa_label_destroy(&profile->label);
+
+ kfree_sensitive(profile);
+}
+
+/**
+ * aa_alloc_profile - allocate, initialize and return a new profile
+ * @hname: name of the profile (NOT NULL)
+ * @gfp: allocation type
+ *
+ * Returns: refcount profile or NULL on failure
+ */
+struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
+ gfp_t gfp)
+{
+ struct aa_profile *profile;
+
+ /* freed by free_profile - usually through aa_put_profile */
+ profile = kzalloc(struct_size(profile, label.vec, 2), gfp);
+ if (!profile)
+ return NULL;
+
+ if (!aa_policy_init(&profile->base, NULL, hname, gfp))
+ goto fail;
+ if (!aa_label_init(&profile->label, 1, gfp))
+ goto fail;
+
+ /* update being set needed by fs interface */
+ if (!proxy) {
+ proxy = aa_alloc_proxy(&profile->label, gfp);
+ if (!proxy)
+ goto fail;
+ } else
+ aa_get_proxy(proxy);
+ profile->label.proxy = proxy;
+
+ profile->label.hname = profile->base.hname;
+ profile->label.flags |= FLAG_PROFILE;
+ profile->label.vec[0] = profile;
+
+ /* refcount released by caller */
+ return profile;
+
+fail:
+ aa_free_profile(profile);
+
+ return NULL;
+}
+
+/* TODO: profile accounting - setup in remove */
+
+/**
+ * __strn_find_child - find a profile on @head list using substring of @name
+ * @head: list to search (NOT NULL)
+ * @name: name of profile (NOT NULL)
+ * @len: length of @name substring to match
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted profile ptr, or NULL if not found
+ */
+static struct aa_profile *__strn_find_child(struct list_head *head,
+ const char *name, int len)
+{
+ return (struct aa_profile *)__policy_strn_find(head, name, len);
+}
+
+/**
+ * __find_child - find a profile on @head list with a name matching @name
+ * @head: list to search (NOT NULL)
+ * @name: name of profile (NOT NULL)
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted profile ptr, or NULL if not found
+ */
+static struct aa_profile *__find_child(struct list_head *head, const char *name)
+{
+ return __strn_find_child(head, name, strlen(name));
+}
+
+/**
+ * aa_find_child - find a profile by @name in @parent
+ * @parent: profile to search (NOT NULL)
+ * @name: profile name to search for (NOT NULL)
+ *
+ * Returns: a refcounted profile or NULL if not found
+ */
+struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
+{
+ struct aa_profile *profile;
+
+ rcu_read_lock();
+ do {
+ profile = __find_child(&parent->base.profiles, name);
+ } while (profile && !aa_get_profile_not0(profile));
+ 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_lookupn_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_label *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_lookupn_ns(labels_ns(base), ns_name, ns_len);
+ if (!ns)
+ return NULL;
+ } else
+ ns = aa_get_ns(labels_ns(base));
+
+ 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;
+}
+
+/**
+ * aa_new_null_profile - create or find a null-X learning profile
+ * @parent: profile that caused this profile to be created (NOT NULL)
+ * @hat: true if the null- learning profile is a hat
+ * @base: name to base the null profile off of
+ * @gfp: type of allocation
+ *
+ * Find/Create a null- complain mode profile used in learning mode. The
+ * name of the profile is unique and follows the format of parent//null-XXX.
+ * where XXX is based on the @name or if that fails or is not supplied
+ * a unique number
+ *
+ * null profiles are added to the profile list but the list does not
+ * hold a count on them so that they are automatically released when
+ * not in use.
+ *
+ * Returns: new refcounted profile else NULL on failure
+ */
+struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
+ const char *base, gfp_t gfp)
+{
+ struct aa_profile *p, *profile;
+ const char *bname;
+ char *name = NULL;
+
+ AA_BUG(!parent);
+
+ if (base) {
+ name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
+ gfp);
+ if (name) {
+ sprintf(name, "%s//null-%s", parent->base.hname, base);
+ goto name;
+ }
+ /* fall through to try shorter uniq */
+ }
+
+ name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
+ if (!name)
+ return NULL;
+ sprintf(name, "%s//null-%x", parent->base.hname,
+ atomic_inc_return(&parent->ns->uniq_null));
+
+name:
+ /* lookup to see if this is a dup creation */
+ bname = basename(name);
+ profile = aa_find_child(parent, bname);
+ if (profile)
+ goto out;
+
+ profile = aa_alloc_profile(name, NULL, gfp);
+ if (!profile)
+ goto fail;
+
+ profile->mode = APPARMOR_COMPLAIN;
+ profile->label.flags |= FLAG_NULL;
+ if (hat)
+ profile->label.flags |= FLAG_HAT;
+ profile->path_flags = parent->path_flags;
+
+ /* released on free_profile */
+ rcu_assign_pointer(profile->parent, aa_get_profile(parent));
+ profile->ns = aa_get_ns(parent->ns);
+ profile->file.dfa = aa_get_dfa(nulldfa);
+ profile->policy.dfa = aa_get_dfa(nulldfa);
+
+ mutex_lock_nested(&profile->ns->lock, profile->ns->level);
+ p = __find_child(&parent->base.profiles, bname);
+ if (p) {
+ aa_free_profile(profile);
+ profile = aa_get_profile(p);
+ } else {
+ __add_profile(&parent->base.profiles, profile);
+ }
+ mutex_unlock(&profile->ns->lock);
+
+ /* refcount released by caller */
+out:
+ kfree(name);
+
+ return profile;
+
+fail:
+ kfree(name);
+ aa_free_profile(profile);
+ return NULL;
+}
+
+/**
+ * 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->label.flags & FLAG_IMMUTIBLE) {
+ *info = "cannot replace immutable 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);
+ }
+}
+
+/**
+ * audit_policy - Do auditing of policy changes
+ * @label: label to check if it can manage policy
+ * @op: policy operation being performed
+ * @ns_name: name of namespace being manipulated
+ * @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_label *label, const char *op,
+ const char *ns_name, const char *name,
+ const char *info, int error)
+{
+ DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, op);
+
+ aad(&sa)->iface.ns = ns_name;
+ aad(&sa)->name = name;
+ aad(&sa)->info = info;
+ aad(&sa)->error = error;
+ aad(&sa)->label = label;
+
+ aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, audit_cb);
+
+ return error;
+}
+
+/* don't call out to other LSMs in the stack for apparmor policy admin
+ * permissions
+ */
+static int policy_ns_capable(struct aa_label *label,
+ struct user_namespace *userns, int cap)
+{
+ int err;
+
+ /* check for MAC_ADMIN cap in cred */
+ err = cap_capable(current_cred(), userns, cap, CAP_OPT_NONE);
+ if (!err)
+ err = aa_capable(label, cap, CAP_OPT_NONE);
+
+ return err;
+}
+
+/**
+ * aa_policy_view_capable - check if viewing policy in at @ns is allowed
+ * label: label that is trying to view policy in ns
+ * ns: namespace being viewed by @label (may be NULL if @label's ns)
+ * 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 aa_policy_view_capable(struct aa_label *label, struct aa_ns *ns)
+{
+ struct user_namespace *user_ns = current_user_ns();
+ struct aa_ns *view_ns = labels_view(label);
+ 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;
+
+ return response;
+}
+
+bool aa_policy_admin_capable(struct aa_label *label, struct aa_ns *ns)
+{
+ struct user_namespace *user_ns = current_user_ns();
+ bool capable = policy_ns_capable(label, user_ns, CAP_MAC_ADMIN) == 0;
+
+ AA_DEBUG("cap_mac_admin? %d\n", capable);
+ AA_DEBUG("policy locked? %d\n", aa_g_lock_policy);
+
+ return aa_policy_view_capable(label, ns) && capable &&
+ !aa_g_lock_policy;
+}
+
+bool aa_current_policy_view_capable(struct aa_ns *ns)
+{
+ struct aa_label *label;
+ bool res;
+
+ label = __begin_current_label_crit_section();
+ res = aa_policy_view_capable(label, ns);
+ __end_current_label_crit_section(label);
+
+ return res;
+}
+
+bool aa_current_policy_admin_capable(struct aa_ns *ns)
+{
+ struct aa_label *label;
+ bool res;
+
+ label = __begin_current_label_crit_section();
+ res = aa_policy_admin_capable(label, ns);
+ __end_current_label_crit_section(label);
+
+ return res;
+}
+
+/**
+ * aa_may_manage_policy - can the current task manage policy
+ * @label: label 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_label *label, struct aa_ns *ns, u32 mask)
+{
+ const char *op;
+
+ if (mask & AA_MAY_REMOVE_POLICY)
+ op = OP_PROF_RM;
+ else if (mask & AA_MAY_REPLACE_POLICY)
+ op = OP_PROF_REPL;
+ else
+ op = OP_PROF_LOAD;
+
+ /* check if loading policy is locked out */
+ if (aa_g_lock_policy)
+ return audit_policy(label, op, NULL, NULL, "policy_locked",
+ -EACCES);
+
+ if (!aa_policy_admin_capable(label, ns))
+ return audit_policy(label, 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)
+{
+ 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);
+ 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_label_replace(&old->label, &new->label);
+ /* migrate dents must come after label replacement b/c update */
+ __aafs_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;
+}
+
+static void share_name(struct aa_profile *old, struct aa_profile *new)
+{
+ aa_put_str(new->base.hname);
+ aa_get_str(old->base.hname);
+ new->base.hname = old->base.hname;
+ new->base.name = old->base.name;
+ new->label.hname = old->label.hname;
+}
+
+/* Update to newest version of parent after previous replacements
+ * Returns: unrefcount newest version of parent
+ */
+static struct aa_profile *update_to_newest_parent(struct aa_profile *new)
+{
+ struct aa_profile *parent, *newest;
+
+ parent = rcu_dereference_protected(new->parent,
+ mutex_is_locked(&new->ns->lock));
+ newest = aa_get_newest_profile(parent);
+
+ /* parent replaced in this atomic set? */
+ if (newest != parent) {
+ aa_put_profile(parent);
+ rcu_assign_pointer(new->parent, newest);
+ } else
+ aa_put_profile(newest);
+
+ return newest;
+}
+
+/**
+ * aa_replace_profiles - replace profile(s) on the profile list
+ * @policy_ns: namespace load is occurring on
+ * @label: label that is attempting to load/replace policy
+ * @mask: permission mask
+ * @udata: serialized data stream (NOT NULL)
+ *
+ * unpack and replace a profile on the profile list and uses of that profile
+ * by any task creds via invalidating the old version of the profile, which
+ * tasks will notice to update their own cred. 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 *policy_ns, struct aa_label *label,
+ u32 mask, struct aa_loaddata *udata)
+{
+ const char *ns_name = NULL, *info = NULL;
+ struct aa_ns *ns = NULL;
+ struct aa_load_ent *ent, *tmp;
+ struct aa_loaddata *rawdata_ent;
+ const char *op;
+ ssize_t count, error;
+ LIST_HEAD(lh);
+
+ op = mask & AA_MAY_REPLACE_POLICY ? OP_PROF_REPL : OP_PROF_LOAD;
+ aa_get_loaddata(udata);
+ /* 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(policy_ns ? policy_ns : labels_ns(label),
+ ns_name);
+ if (IS_ERR(ns)) {
+ op = OP_PROF_LOAD;
+ info = "failed to prepare namespace";
+ error = PTR_ERR(ns);
+ ns = NULL;
+ ent = NULL;
+ goto fail;
+ }
+ } else
+ ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(label));
+
+ mutex_lock_nested(&ns->lock, ns->level);
+ /* check for duplicate rawdata blobs: space and file dedup */
+ if (!list_empty(&ns->rawdata_list)) {
+ list_for_each_entry(rawdata_ent, &ns->rawdata_list, list) {
+ if (aa_rawdata_eq(rawdata_ent, udata)) {
+ struct aa_loaddata *tmp;
+
+ tmp = __aa_get_loaddata(rawdata_ent);
+ /* check we didn't fail the race */
+ if (tmp) {
+ aa_put_loaddata(udata);
+ udata = tmp;
+ break;
+ }
+ }
+ }
+ }
+ /* setup parent and ns info */
+ list_for_each_entry(ent, &lh, list) {
+ struct aa_policy *policy;
+
+ if (aa_g_export_binary)
+ ent->new->rawdata = aa_get_loaddata(udata);
+ error = __lookup_replace(ns, ent->new->base.hname,
+ !(mask & AA_MAY_REPLACE_POLICY),
+ &ent->old, &info);
+ if (error)
+ goto fail_lock;
+
+ if (ent->new->rename) {
+ error = __lookup_replace(ns, ent->new->rename,
+ !(mask & AA_MAY_REPLACE_POLICY),
+ &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 */
+ if (!udata->dents[AAFS_LOADDATA_DIR] && aa_g_export_binary) {
+ error = __aa_fs_create_rawdata(ns, udata);
+ if (error) {
+ info = "failed to create raw_data dir and files";
+ ent = NULL;
+ goto fail_lock;
+ }
+ }
+ list_for_each_entry(ent, &lh, list) {
+ if (!ent->old) {
+ 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 = __aafs_profile_mkdir(ent->new, parent);
+ }
+
+ if (error) {
+ info = "failed to create";
+ goto fail_lock;
+ }
+ }
+
+ /* Done with checks that may fail - do actual replacement */
+ __aa_bump_ns_revision(ns);
+ if (aa_g_export_binary)
+ __aa_loaddata_update(udata, ns->revision);
+ 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;
+
+ if (ent->old && ent->old->rawdata == ent->new->rawdata &&
+ ent->new->rawdata) {
+ /* dedup actual profile replacement */
+ audit_policy(label, op, ns_name, ent->new->base.hname,
+ "same as current profile, skipping",
+ error);
+ /* break refcount cycle with proxy. */
+ aa_put_proxy(ent->new->label.proxy);
+ ent->new->label.proxy = NULL;
+ goto skip;
+ }
+
+ /*
+ * TODO: finer dedup based on profile range in data. Load set
+ * can differ but profile may remain unchanged
+ */
+ audit_policy(label, op, ns_name, ent->new->base.hname, NULL,
+ error);
+
+ if (ent->old) {
+ share_name(ent->old, ent->new);
+ __replace_profile(ent->old, ent->new);
+ } else {
+ struct list_head *lh;
+
+ if (rcu_access_pointer(ent->new->parent)) {
+ struct aa_profile *parent;
+
+ parent = update_to_newest_parent(ent->new);
+ lh = &parent->base.profiles;
+ } else
+ lh = &ns->base.profiles;
+ __add_profile(lh, ent->new);
+ }
+ skip:
+ aa_load_ent_free(ent);
+ }
+ __aa_labelset_update_subtree(ns);
+ mutex_unlock(&ns->lock);
+
+out:
+ aa_put_ns(ns);
+ aa_put_loaddata(udata);
+ kfree(ns_name);
+
+ if (error)
+ return error;
+ return udata->size;
+
+fail_lock:
+ mutex_unlock(&ns->lock);
+
+ /* audit cause of failure */
+ op = (ent && !ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
+fail:
+ audit_policy(label, op, ns_name, ent ? ent->new->base.hname : NULL,
+ 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 = (!tmp->old) ? OP_PROF_LOAD : OP_PROF_REPL;
+ audit_policy(label, 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
+ * @policy_ns: namespace the remove is being done from
+ * @subj: label 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 preconfinement values
+ *
+ * Returns: size of data consume else error code if fails
+ */
+ssize_t aa_remove_profiles(struct aa_ns *policy_ns, struct aa_label *subj,
+ char *fqname, size_t size)
+{
+ struct aa_ns *ns = NULL;
+ struct aa_profile *profile = NULL;
+ const char *name = fqname, *info = NULL;
+ const char *ns_name = NULL;
+ ssize_t error = 0;
+
+ if (*fqname == 0) {
+ info = "no profile specified";
+ error = -ENOENT;
+ goto fail;
+ }
+
+ if (fqname[0] == ':') {
+ size_t ns_len;
+
+ name = aa_splitn_fqname(fqname, size, &ns_name, &ns_len);
+ /* released below */
+ ns = aa_lookupn_ns(policy_ns ? policy_ns : labels_ns(subj),
+ ns_name, ns_len);
+ if (!ns) {
+ info = "namespace does not exist";
+ error = -ENOENT;
+ goto fail;
+ }
+ } else
+ /* released below */
+ ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(subj));
+
+ if (!name) {
+ /* remove namespace - can only happen if fqname[0] == ':' */
+ mutex_lock_nested(&ns->parent->lock, ns->parent->level);
+ __aa_bump_ns_revision(ns);
+ __aa_remove_ns(ns);
+ mutex_unlock(&ns->parent->lock);
+ } else {
+ /* remove profile */
+ mutex_lock_nested(&ns->lock, ns->level);
+ 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;
+ __aa_bump_ns_revision(ns);
+ __remove_profile(profile);
+ __aa_labelset_update_subtree(ns);
+ 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;
+}