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 // 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);
 
     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->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;
 }

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