[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/security/apparmor/domain.c b/src/kernel/linux/v4.14/security/apparmor/domain.c
new file mode 100644
index 0000000..67bf8b7
--- /dev/null
+++ b/src/kernel/linux/v4.14/security/apparmor/domain.c
@@ -0,0 +1,1288 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor policy attachment and domain transitions
+ *
+ * Copyright (C) 2002-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#include <linux/errno.h>
+#include <linux/fdtable.h>
+#include <linux/file.h>
+#include <linux/mount.h>
+#include <linux/syscalls.h>
+#include <linux/tracehook.h>
+#include <linux/personality.h>
+
+#include "include/audit.h"
+#include "include/apparmorfs.h"
+#include "include/context.h"
+#include "include/domain.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"
+
+/**
+ * aa_free_domain_entries - free entries in a domain table
+ * @domain: the domain table to free (MAYBE NULL)
+ */
+void aa_free_domain_entries(struct aa_domain *domain)
+{
+ int i;
+ if (domain) {
+ if (!domain->table)
+ return;
+
+ for (i = 0; i < domain->size; i++)
+ kzfree(domain->table[i]);
+ kzfree(domain->table);
+ domain->table = NULL;
+ }
+}
+
+/**
+ * may_change_ptraced_domain - check if can change profile on ptraced task
+ * @to_label: profile to change to (NOT NULL)
+ * @info: message if there is an error
+ *
+ * Check if current is ptraced and if so if the tracing task is allowed
+ * to trace the new domain
+ *
+ * Returns: %0 or error if change not allowed
+ */
+static int may_change_ptraced_domain(struct aa_label *to_label,
+ const char **info)
+{
+ struct task_struct *tracer;
+ struct aa_label *tracerl = NULL;
+ int error = 0;
+
+ rcu_read_lock();
+ tracer = ptrace_parent(current);
+ if (tracer)
+ /* released below */
+ tracerl = aa_get_task_label(tracer);
+
+ /* not ptraced */
+ if (!tracer || unconfined(tracerl))
+ goto out;
+
+ error = aa_may_ptrace(tracerl, to_label, PTRACE_MODE_ATTACH);
+
+out:
+ rcu_read_unlock();
+ aa_put_label(tracerl);
+
+ if (error)
+ *info = "ptrace prevents transition";
+ return error;
+}
+
+/**** TODO: dedup to aa_label_match - needs perm and dfa, merging
+ * specifically this is an exact copy of aa_label_match except
+ * aa_compute_perms is replaced with aa_compute_fperms
+ * and policy.dfa with file.dfa
+ ****/
+/* match a profile and its associated ns component if needed
+ * Assumes visibility test has already been done.
+ * If a subns profile is not to be matched should be prescreened with
+ * visibility test.
+ */
+static inline unsigned int match_component(struct aa_profile *profile,
+ struct aa_profile *tp,
+ bool stack, unsigned int state)
+{
+ const char *ns_name;
+
+ if (stack)
+ state = aa_dfa_match(profile->file.dfa, state, "&");
+ if (profile->ns == tp->ns)
+ return aa_dfa_match(profile->file.dfa, state, tp->base.hname);
+
+ /* try matching with namespace name and then profile */
+ ns_name = aa_ns_name(profile->ns, tp->ns, true);
+ state = aa_dfa_match_len(profile->file.dfa, state, ":", 1);
+ state = aa_dfa_match(profile->file.dfa, state, ns_name);
+ state = aa_dfa_match_len(profile->file.dfa, state, ":", 1);
+ return aa_dfa_match(profile->file.dfa, state, tp->base.hname);
+}
+
+/**
+ * label_compound_match - find perms for full compound label
+ * @profile: profile to find perms for
+ * @label: label to check access permissions for
+ * @stack: whether this is a stacking request
+ * @start: state to start match in
+ * @subns: whether to do permission checks on components in a subns
+ * @request: permissions to request
+ * @perms: perms struct to set
+ *
+ * Returns: 0 on success else ERROR
+ *
+ * For the label A//&B//&C this does the perm match for A//&B//&C
+ * @perms should be preinitialized with allperms OR a previous permission
+ * check to be stacked.
+ */
+static int label_compound_match(struct aa_profile *profile,
+ struct aa_label *label, bool stack,
+ unsigned int state, bool subns, u32 request,
+ struct aa_perms *perms)
+{
+ struct aa_profile *tp;
+ struct label_it i;
+ struct path_cond cond = { };
+
+ /* find first subcomponent that is visible */
+ label_for_each(i, label, tp) {
+ if (!aa_ns_visible(profile->ns, tp->ns, subns))
+ continue;
+ state = match_component(profile, tp, stack, state);
+ if (!state)
+ goto fail;
+ goto next;
+ }
+
+ /* no component visible */
+ *perms = allperms;
+ return 0;
+
+next:
+ label_for_each_cont(i, label, tp) {
+ if (!aa_ns_visible(profile->ns, tp->ns, subns))
+ continue;
+ state = aa_dfa_match(profile->file.dfa, state, "//&");
+ state = match_component(profile, tp, false, state);
+ if (!state)
+ goto fail;
+ }
+ *perms = aa_compute_fperms(profile->file.dfa, state, &cond);
+ aa_apply_modes_to_perms(profile, perms);
+ if ((perms->allow & request) != request)
+ return -EACCES;
+
+ return 0;
+
+fail:
+ *perms = nullperms;
+ return -EACCES;
+}
+
+/**
+ * label_components_match - find perms for all subcomponents of a label
+ * @profile: profile to find perms for
+ * @label: label to check access permissions for
+ * @stack: whether this is a stacking request
+ * @start: state to start match in
+ * @subns: whether to do permission checks on components in a subns
+ * @request: permissions to request
+ * @perms: an initialized perms struct to add accumulation to
+ *
+ * Returns: 0 on success else ERROR
+ *
+ * For the label A//&B//&C this does the perm match for each of A and B and C
+ * @perms should be preinitialized with allperms OR a previous permission
+ * check to be stacked.
+ */
+static int label_components_match(struct aa_profile *profile,
+ struct aa_label *label, bool stack,
+ unsigned int start, bool subns, u32 request,
+ struct aa_perms *perms)
+{
+ struct aa_profile *tp;
+ struct label_it i;
+ struct aa_perms tmp;
+ struct path_cond cond = { };
+ unsigned int state = 0;
+
+ /* find first subcomponent to test */
+ label_for_each(i, label, tp) {
+ if (!aa_ns_visible(profile->ns, tp->ns, subns))
+ continue;
+ state = match_component(profile, tp, stack, start);
+ if (!state)
+ goto fail;
+ goto next;
+ }
+
+ /* no subcomponents visible - no change in perms */
+ return 0;
+
+next:
+ tmp = aa_compute_fperms(profile->file.dfa, state, &cond);
+ aa_apply_modes_to_perms(profile, &tmp);
+ aa_perms_accum(perms, &tmp);
+ label_for_each_cont(i, label, tp) {
+ if (!aa_ns_visible(profile->ns, tp->ns, subns))
+ continue;
+ state = match_component(profile, tp, stack, start);
+ if (!state)
+ goto fail;
+ tmp = aa_compute_fperms(profile->file.dfa, state, &cond);
+ aa_apply_modes_to_perms(profile, &tmp);
+ aa_perms_accum(perms, &tmp);
+ }
+
+ if ((perms->allow & request) != request)
+ return -EACCES;
+
+ return 0;
+
+fail:
+ *perms = nullperms;
+ return -EACCES;
+}
+
+/**
+ * label_match - do a multi-component label match
+ * @profile: profile to match against (NOT NULL)
+ * @label: label to match (NOT NULL)
+ * @stack: whether this is a stacking request
+ * @state: state to start in
+ * @subns: whether to match subns components
+ * @request: permission request
+ * @perms: Returns computed perms (NOT NULL)
+ *
+ * Returns: the state the match finished in, may be the none matching state
+ */
+static int label_match(struct aa_profile *profile, struct aa_label *label,
+ bool stack, unsigned int state, bool subns, u32 request,
+ struct aa_perms *perms)
+{
+ int error;
+
+ *perms = nullperms;
+ error = label_compound_match(profile, label, stack, state, subns,
+ request, perms);
+ if (!error)
+ return error;
+
+ *perms = allperms;
+ return label_components_match(profile, label, stack, state, subns,
+ request, perms);
+}
+
+/******* end TODO: dedup *****/
+
+/**
+ * change_profile_perms - find permissions for change_profile
+ * @profile: the current profile (NOT NULL)
+ * @target: label to transition to (NOT NULL)
+ * @stack: whether this is a stacking request
+ * @request: requested perms
+ * @start: state to start matching in
+ *
+ *
+ * Returns: permission set
+ *
+ * currently only matches full label A//&B//&C or individual components A, B, C
+ * not arbitrary combinations. Eg. A//&B, C
+ */
+static int change_profile_perms(struct aa_profile *profile,
+ struct aa_label *target, bool stack,
+ u32 request, unsigned int start,
+ struct aa_perms *perms)
+{
+ if (profile_unconfined(profile)) {
+ perms->allow = AA_MAY_CHANGE_PROFILE | AA_MAY_ONEXEC;
+ perms->audit = perms->quiet = perms->kill = 0;
+ return 0;
+ }
+
+ /* TODO: add profile in ns screening */
+ return label_match(profile, target, stack, start, true, request, perms);
+}
+
+/**
+ * __attach_match_ - find an attachment match
+ * @name - to match against (NOT NULL)
+ * @head - profile list to walk (NOT NULL)
+ *
+ * Do a linear search on the profiles in the list. There is a matching
+ * preference where an exact match is preferred over a name which uses
+ * expressions to match, and matching expressions with the greatest
+ * xmatch_len are preferred.
+ *
+ * Requires: @head not be shared or have appropriate locks held
+ *
+ * Returns: profile or NULL if no match found
+ */
+static struct aa_profile *__attach_match(const char *name,
+ struct list_head *head)
+{
+ int len = 0;
+ struct aa_profile *profile, *candidate = NULL;
+
+ list_for_each_entry_rcu(profile, head, base.list) {
+ if (profile->label.flags & FLAG_NULL)
+ continue;
+ if (profile->xmatch && profile->xmatch_len > len) {
+ unsigned int state = aa_dfa_match(profile->xmatch,
+ DFA_START, name);
+ u32 perm = dfa_user_allow(profile->xmatch, state);
+ /* any accepting state means a valid match. */
+ if (perm & MAY_EXEC) {
+ candidate = profile;
+ len = profile->xmatch_len;
+ }
+ } else if (!strcmp(profile->base.name, name))
+ /* exact non-re match, no more searching required */
+ return profile;
+ }
+
+ return candidate;
+}
+
+/**
+ * find_attach - do attachment search for unconfined processes
+ * @ns: the current namespace (NOT NULL)
+ * @list: list to search (NOT NULL)
+ * @name: the executable name to match against (NOT NULL)
+ *
+ * Returns: label or NULL if no match found
+ */
+static struct aa_label *find_attach(struct aa_ns *ns, struct list_head *list,
+ const char *name)
+{
+ struct aa_profile *profile;
+
+ rcu_read_lock();
+ profile = aa_get_profile(__attach_match(name, list));
+ rcu_read_unlock();
+
+ return profile ? &profile->label : NULL;
+}
+
+static const char *next_name(int xtype, const char *name)
+{
+ return NULL;
+}
+
+/**
+ * x_table_lookup - lookup an x transition name via transition table
+ * @profile: current profile (NOT NULL)
+ * @xindex: index into x transition table
+ * @name: returns: name tested to find label (NOT NULL)
+ *
+ * Returns: refcounted label, or NULL on failure (MAYBE NULL)
+ */
+struct aa_label *x_table_lookup(struct aa_profile *profile, u32 xindex,
+ const char **name)
+{
+ struct aa_label *label = NULL;
+ u32 xtype = xindex & AA_X_TYPE_MASK;
+ int index = xindex & AA_X_INDEX_MASK;
+
+ AA_BUG(!name);
+
+ /* index is guaranteed to be in range, validated at load time */
+ /* TODO: move lookup parsing to unpack time so this is a straight
+ * index into the resultant label
+ */
+ for (*name = profile->file.trans.table[index]; !label && *name;
+ *name = next_name(xtype, *name)) {
+ if (xindex & AA_X_CHILD) {
+ struct aa_profile *new_profile;
+ /* release by caller */
+ new_profile = aa_find_child(profile, *name);
+ if (new_profile)
+ label = &new_profile->label;
+ continue;
+ }
+ label = aa_label_parse(&profile->label, *name, GFP_ATOMIC,
+ true, false);
+ if (IS_ERR(label))
+ label = NULL;
+ }
+
+ /* released by caller */
+
+ return label;
+}
+
+/**
+ * x_to_label - get target label for a given xindex
+ * @profile: current profile (NOT NULL)
+ * @name: name to lookup (NOT NULL)
+ * @xindex: index into x transition table
+ * @lookupname: returns: name used in lookup if one was specified (NOT NULL)
+ *
+ * find label for a transition index
+ *
+ * Returns: refcounted label or NULL if not found available
+ */
+static struct aa_label *x_to_label(struct aa_profile *profile,
+ const char *name, u32 xindex,
+ const char **lookupname,
+ const char **info)
+{
+ struct aa_label *new = NULL;
+ struct aa_ns *ns = profile->ns;
+ u32 xtype = xindex & AA_X_TYPE_MASK;
+ const char *stack = NULL;
+
+ switch (xtype) {
+ case AA_X_NONE:
+ /* fail exec unless ix || ux fallback - handled by caller */
+ *lookupname = NULL;
+ break;
+ case AA_X_TABLE:
+ /* TODO: fix when perm mapping done at unload */
+ stack = profile->file.trans.table[xindex & AA_X_INDEX_MASK];
+ if (*stack != '&') {
+ /* released by caller */
+ new = x_table_lookup(profile, xindex, lookupname);
+ stack = NULL;
+ break;
+ }
+ /* fall through to X_NAME */
+ case AA_X_NAME:
+ if (xindex & AA_X_CHILD)
+ /* released by caller */
+ new = find_attach(ns, &profile->base.profiles,
+ name);
+ else
+ /* released by caller */
+ new = find_attach(ns, &ns->base.profiles,
+ name);
+ *lookupname = name;
+ break;
+ }
+
+ if (!new) {
+ if (xindex & AA_X_INHERIT) {
+ /* (p|c|n)ix - don't change profile but do
+ * use the newest version
+ */
+ *info = "ix fallback";
+ /* no profile && no error */
+ new = aa_get_newest_label(&profile->label);
+ } else if (xindex & AA_X_UNCONFINED) {
+ new = aa_get_newest_label(ns_unconfined(profile->ns));
+ *info = "ux fallback";
+ }
+ }
+
+ if (new && stack) {
+ /* base the stack on post domain transition */
+ struct aa_label *base = new;
+
+ new = aa_label_parse(base, stack, GFP_ATOMIC, true, false);
+ if (IS_ERR(new))
+ new = NULL;
+ aa_put_label(base);
+ }
+
+ /* released by caller */
+ return new;
+}
+
+static struct aa_label *profile_transition(struct aa_profile *profile,
+ const struct linux_binprm *bprm,
+ char *buffer, struct path_cond *cond,
+ bool *secure_exec)
+{
+ struct aa_label *new = NULL;
+ const char *info = NULL, *name = NULL, *target = NULL;
+ unsigned int state = profile->file.start;
+ struct aa_perms perms = {};
+ bool nonewprivs = false;
+ int error = 0;
+
+ AA_BUG(!profile);
+ AA_BUG(!bprm);
+ AA_BUG(!buffer);
+
+ error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer,
+ &name, &info, profile->disconnected);
+ if (error) {
+ if (profile_unconfined(profile) ||
+ (profile->label.flags & FLAG_IX_ON_NAME_ERROR)) {
+ AA_DEBUG("name lookup ix on error");
+ error = 0;
+ new = aa_get_newest_label(&profile->label);
+ }
+ name = bprm->filename;
+ goto audit;
+ }
+
+ if (profile_unconfined(profile)) {
+ new = find_attach(profile->ns, &profile->ns->base.profiles,
+ name);
+ if (new) {
+ AA_DEBUG("unconfined attached to new label");
+ return new;
+ }
+ AA_DEBUG("unconfined exec no attachment");
+ return aa_get_newest_label(&profile->label);
+ }
+
+ /* find exec permissions for name */
+ state = aa_str_perms(profile->file.dfa, state, name, cond, &perms);
+ if (perms.allow & MAY_EXEC) {
+ /* exec permission determine how to transition */
+ new = x_to_label(profile, name, perms.xindex, &target, &info);
+ if (new && new->proxy == profile->label.proxy && info) {
+ /* hack ix fallback - improve how this is detected */
+ goto audit;
+ } else if (!new) {
+ error = -EACCES;
+ info = "profile transition not found";
+ /* remove MAY_EXEC to audit as failure */
+ perms.allow &= ~MAY_EXEC;
+ }
+ } else if (COMPLAIN_MODE(profile)) {
+ /* no exec permission - learning mode */
+ struct aa_profile *new_profile = aa_new_null_profile(profile,
+ false, name,
+ GFP_ATOMIC);
+ if (!new_profile) {
+ error = -ENOMEM;
+ info = "could not create null profile";
+ } else {
+ error = -EACCES;
+ new = &new_profile->label;
+ }
+ perms.xindex |= AA_X_UNSAFE;
+ } else
+ /* fail exec */
+ error = -EACCES;
+
+ if (!new)
+ goto audit;
+
+ /* Policy has specified a domain transitions. if no_new_privs and
+ * confined and not transitioning to the current domain fail.
+ *
+ * NOTE: Domain transitions from unconfined and to stritly stacked
+ * subsets are allowed even when no_new_privs is set because this
+ * aways results in a further reduction of permissions.
+ */
+ if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) &&
+ !profile_unconfined(profile) &&
+ !aa_label_is_subset(new, &profile->label)) {
+ error = -EPERM;
+ info = "no new privs";
+ nonewprivs = true;
+ perms.allow &= ~MAY_EXEC;
+ goto audit;
+ }
+
+ if (!(perms.xindex & AA_X_UNSAFE)) {
+ if (DEBUG_ON) {
+ dbg_printk("apparmor: scrubbing environment variables"
+ " for %s profile=", name);
+ aa_label_printk(new, GFP_ATOMIC);
+ dbg_printk("\n");
+ }
+ *secure_exec = true;
+ }
+
+audit:
+ aa_audit_file(profile, &perms, OP_EXEC, MAY_EXEC, name, target, new,
+ cond->uid, info, error);
+ if (!new || nonewprivs) {
+ aa_put_label(new);
+ return ERR_PTR(error);
+ }
+
+ return new;
+}
+
+static int profile_onexec(struct aa_profile *profile, struct aa_label *onexec,
+ bool stack, const struct linux_binprm *bprm,
+ char *buffer, struct path_cond *cond,
+ bool *secure_exec)
+{
+ unsigned int state = profile->file.start;
+ struct aa_perms perms = {};
+ const char *xname = NULL, *info = "change_profile onexec";
+ int error = -EACCES;
+
+ AA_BUG(!profile);
+ AA_BUG(!onexec);
+ AA_BUG(!bprm);
+ AA_BUG(!buffer);
+
+ if (profile_unconfined(profile)) {
+ /* change_profile on exec already granted */
+ /*
+ * NOTE: Domain transitions from unconfined are allowed
+ * even when no_new_privs is set because this aways results
+ * in a further reduction of permissions.
+ */
+ return 0;
+ }
+
+ error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer,
+ &xname, &info, profile->disconnected);
+ if (error) {
+ if (profile_unconfined(profile) ||
+ (profile->label.flags & FLAG_IX_ON_NAME_ERROR)) {
+ AA_DEBUG("name lookup ix on error");
+ error = 0;
+ }
+ xname = bprm->filename;
+ goto audit;
+ }
+
+ /* find exec permissions for name */
+ state = aa_str_perms(profile->file.dfa, state, xname, cond, &perms);
+ if (!(perms.allow & AA_MAY_ONEXEC)) {
+ info = "no change_onexec valid for executable";
+ goto audit;
+ }
+ /* test if this exec can be paired with change_profile onexec.
+ * onexec permission is linked to exec with a standard pairing
+ * exec\0change_profile
+ */
+ state = aa_dfa_null_transition(profile->file.dfa, state);
+ error = change_profile_perms(profile, onexec, stack, AA_MAY_ONEXEC,
+ state, &perms);
+ if (error) {
+ perms.allow &= ~AA_MAY_ONEXEC;
+ goto audit;
+ }
+ /* Policy has specified a domain transitions. if no_new_privs and
+ * confined and not transitioning to the current domain fail.
+ *
+ * NOTE: Domain transitions from unconfined and to stritly stacked
+ * subsets are allowed even when no_new_privs is set because this
+ * aways results in a further reduction of permissions.
+ */
+ if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) &&
+ !profile_unconfined(profile) &&
+ !aa_label_is_subset(onexec, &profile->label)) {
+ error = -EPERM;
+ info = "no new privs";
+ perms.allow &= ~AA_MAY_ONEXEC;
+ goto audit;
+ }
+
+ if (!(perms.xindex & AA_X_UNSAFE)) {
+ if (DEBUG_ON) {
+ dbg_printk("apparmor: scrubbing environment "
+ "variables for %s label=", xname);
+ aa_label_printk(onexec, GFP_ATOMIC);
+ dbg_printk("\n");
+ }
+ *secure_exec = true;
+ }
+
+audit:
+ return aa_audit_file(profile, &perms, OP_EXEC, AA_MAY_ONEXEC, xname,
+ NULL, onexec, cond->uid, info, error);
+}
+
+/* ensure none ns domain transitions are correctly applied with onexec */
+
+static struct aa_label *handle_onexec(struct aa_label *label,
+ struct aa_label *onexec, bool stack,
+ const struct linux_binprm *bprm,
+ char *buffer, struct path_cond *cond,
+ bool *unsafe)
+{
+ struct aa_profile *profile;
+ struct aa_label *new;
+ int error;
+
+ AA_BUG(!label);
+ AA_BUG(!onexec);
+ AA_BUG(!bprm);
+ AA_BUG(!buffer);
+
+ if (!stack) {
+ error = fn_for_each_in_ns(label, profile,
+ profile_onexec(profile, onexec, stack,
+ bprm, buffer, cond, unsafe));
+ if (error)
+ return ERR_PTR(error);
+ new = fn_label_build_in_ns(label, profile, GFP_ATOMIC,
+ aa_get_newest_label(onexec),
+ profile_transition(profile, bprm, buffer,
+ cond, unsafe));
+
+ } else {
+ /* TODO: determine how much we want to losen this */
+ error = fn_for_each_in_ns(label, profile,
+ profile_onexec(profile, onexec, stack, bprm,
+ buffer, cond, unsafe));
+ if (error)
+ return ERR_PTR(error);
+ new = fn_label_build_in_ns(label, profile, GFP_ATOMIC,
+ aa_label_merge(&profile->label, onexec,
+ GFP_ATOMIC),
+ profile_transition(profile, bprm, buffer,
+ cond, unsafe));
+ }
+
+ if (new)
+ return new;
+
+ /* TODO: get rid of GLOBAL_ROOT_UID */
+ error = fn_for_each_in_ns(label, profile,
+ aa_audit_file(profile, &nullperms, OP_CHANGE_ONEXEC,
+ AA_MAY_ONEXEC, bprm->filename, NULL,
+ onexec, GLOBAL_ROOT_UID,
+ "failed to build target label", -ENOMEM));
+ return ERR_PTR(error);
+}
+
+/**
+ * apparmor_bprm_set_creds - set the new creds on the bprm struct
+ * @bprm: binprm for the exec (NOT NULL)
+ *
+ * Returns: %0 or error on failure
+ *
+ * TODO: once the other paths are done see if we can't refactor into a fn
+ */
+int apparmor_bprm_set_creds(struct linux_binprm *bprm)
+{
+ struct aa_task_ctx *ctx;
+ struct aa_label *label, *new = NULL;
+ struct aa_profile *profile;
+ char *buffer = NULL;
+ const char *info = NULL;
+ int error = 0;
+ bool unsafe = false;
+ struct path_cond cond = {
+ file_inode(bprm->file)->i_uid,
+ file_inode(bprm->file)->i_mode
+ };
+
+ if (bprm->called_set_creds)
+ return 0;
+
+ ctx = cred_ctx(bprm->cred);
+ AA_BUG(!ctx);
+
+ label = aa_get_newest_label(ctx->label);
+
+ /* buffer freed below, name is pointer into buffer */
+ get_buffers(buffer);
+ /* Test for onexec first as onexec override other x transitions. */
+ if (ctx->onexec)
+ new = handle_onexec(label, ctx->onexec, ctx->token,
+ bprm, buffer, &cond, &unsafe);
+ else
+ new = fn_label_build(label, profile, GFP_ATOMIC,
+ profile_transition(profile, bprm, buffer,
+ &cond, &unsafe));
+
+ AA_BUG(!new);
+ if (IS_ERR(new)) {
+ error = PTR_ERR(new);
+ goto done;
+ } else if (!new) {
+ error = -ENOMEM;
+ goto done;
+ }
+
+ /* TODO: Add ns level no_new_privs subset test */
+
+ if (bprm->unsafe & LSM_UNSAFE_SHARE) {
+ /* FIXME: currently don't mediate shared state */
+ ;
+ }
+
+ if (bprm->unsafe & (LSM_UNSAFE_PTRACE)) {
+ /* TODO: test needs to be profile of label to new */
+ error = may_change_ptraced_domain(new, &info);
+ if (error)
+ goto audit;
+ }
+
+ if (unsafe) {
+ if (DEBUG_ON) {
+ dbg_printk("scrubbing environment variables for %s "
+ "label=", bprm->filename);
+ aa_label_printk(new, GFP_ATOMIC);
+ dbg_printk("\n");
+ }
+ bprm->secureexec = 1;
+ }
+
+ if (label->proxy != new->proxy) {
+ /* when transitioning clear unsafe personality bits */
+ if (DEBUG_ON) {
+ dbg_printk("apparmor: clearing unsafe personality "
+ "bits. %s label=", bprm->filename);
+ aa_label_printk(new, GFP_ATOMIC);
+ dbg_printk("\n");
+ }
+ bprm->per_clear |= PER_CLEAR_ON_SETID;
+ }
+ aa_put_label(ctx->label);
+ /* transfer reference, released when ctx is freed */
+ ctx->label = new;
+
+done:
+ /* clear out temporary/transitional state from the context */
+ aa_clear_task_ctx_trans(ctx);
+
+ aa_put_label(label);
+ put_buffers(buffer);
+
+ return error;
+
+audit:
+ error = fn_for_each(label, profile,
+ aa_audit_file(profile, &nullperms, OP_EXEC, MAY_EXEC,
+ bprm->filename, NULL, new,
+ file_inode(bprm->file)->i_uid, info,
+ error));
+ aa_put_label(new);
+ goto done;
+}
+
+/*
+ * Functions for self directed profile change
+ */
+
+
+/* helper fn for change_hat
+ *
+ * Returns: label for hat transition OR ERR_PTR. Does NOT return NULL
+ */
+static struct aa_label *build_change_hat(struct aa_profile *profile,
+ const char *name, bool sibling)
+{
+ struct aa_profile *root, *hat = NULL;
+ const char *info = NULL;
+ int error = 0;
+
+ if (sibling && PROFILE_IS_HAT(profile)) {
+ root = aa_get_profile_rcu(&profile->parent);
+ } else if (!sibling && !PROFILE_IS_HAT(profile)) {
+ root = aa_get_profile(profile);
+ } else {
+ info = "conflicting target types";
+ error = -EPERM;
+ goto audit;
+ }
+
+ hat = aa_find_child(root, name);
+ if (!hat) {
+ error = -ENOENT;
+ if (COMPLAIN_MODE(profile)) {
+ hat = aa_new_null_profile(profile, true, name,
+ GFP_KERNEL);
+ if (!hat) {
+ info = "failed null profile create";
+ error = -ENOMEM;
+ }
+ }
+ }
+ aa_put_profile(root);
+
+audit:
+ aa_audit_file(profile, &nullperms, OP_CHANGE_HAT, AA_MAY_CHANGEHAT,
+ name, hat ? hat->base.hname : NULL,
+ hat ? &hat->label : NULL, GLOBAL_ROOT_UID, NULL,
+ error);
+ if (!hat || (error && error != -ENOENT))
+ return ERR_PTR(error);
+ /* if hat && error - complain mode, already audited and we adjust for
+ * complain mode allow by returning hat->label
+ */
+ return &hat->label;
+}
+
+/* helper fn for changing into a hat
+ *
+ * Returns: label for hat transition or ERR_PTR. Does not return NULL
+ */
+static struct aa_label *change_hat(struct aa_label *label, const char *hats[],
+ int count, int flags)
+{
+ struct aa_profile *profile, *root, *hat = NULL;
+ struct aa_label *new;
+ struct label_it it;
+ bool sibling = false;
+ const char *name, *info = NULL;
+ int i, error;
+
+ AA_BUG(!label);
+ AA_BUG(!hats);
+ AA_BUG(count < 1);
+
+ if (PROFILE_IS_HAT(labels_profile(label)))
+ sibling = true;
+
+ /*find first matching hat */
+ for (i = 0; i < count && !hat; i++) {
+ name = hats[i];
+ label_for_each_in_ns(it, labels_ns(label), label, profile) {
+ if (sibling && PROFILE_IS_HAT(profile)) {
+ root = aa_get_profile_rcu(&profile->parent);
+ } else if (!sibling && !PROFILE_IS_HAT(profile)) {
+ root = aa_get_profile(profile);
+ } else { /* conflicting change type */
+ info = "conflicting targets types";
+ error = -EPERM;
+ goto fail;
+ }
+ hat = aa_find_child(root, name);
+ aa_put_profile(root);
+ if (!hat) {
+ if (!COMPLAIN_MODE(profile))
+ goto outer_continue;
+ /* complain mode succeed as if hat */
+ } else if (!PROFILE_IS_HAT(hat)) {
+ info = "target not hat";
+ error = -EPERM;
+ aa_put_profile(hat);
+ goto fail;
+ }
+ aa_put_profile(hat);
+ }
+ /* found a hat for all profiles in ns */
+ goto build;
+outer_continue:
+ ;
+ }
+ /* no hats that match, find appropriate error
+ *
+ * In complain mode audit of the failure is based off of the first
+ * hat supplied. This is done due how userspace interacts with
+ * change_hat.
+ */
+ name = NULL;
+ label_for_each_in_ns(it, labels_ns(label), label, profile) {
+ if (!list_empty(&profile->base.profiles)) {
+ info = "hat not found";
+ error = -ENOENT;
+ goto fail;
+ }
+ }
+ info = "no hats defined";
+ error = -ECHILD;
+
+fail:
+ label_for_each_in_ns(it, labels_ns(label), label, profile) {
+ /*
+ * no target as it has failed to be found or built
+ *
+ * change_hat uses probing and should not log failures
+ * related to missing hats
+ */
+ /* TODO: get rid of GLOBAL_ROOT_UID */
+ if (count > 1 || COMPLAIN_MODE(profile)) {
+ aa_audit_file(profile, &nullperms, OP_CHANGE_HAT,
+ AA_MAY_CHANGEHAT, name, NULL, NULL,
+ GLOBAL_ROOT_UID, info, error);
+ }
+ }
+ return ERR_PTR(error);
+
+build:
+ new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
+ build_change_hat(profile, name, sibling),
+ aa_get_label(&profile->label));
+ if (!new) {
+ info = "label build failed";
+ error = -ENOMEM;
+ goto fail;
+ } /* else if (IS_ERR) build_change_hat has logged error so return new */
+
+ return new;
+}
+
+/**
+ * aa_change_hat - change hat to/from subprofile
+ * @hats: vector of hat names to try changing into (MAYBE NULL if @count == 0)
+ * @count: number of hat names in @hats
+ * @token: magic value to validate the hat change
+ * @flags: flags affecting behavior of the change
+ *
+ * Returns %0 on success, error otherwise.
+ *
+ * Change to the first profile specified in @hats that exists, and store
+ * the @hat_magic in the current task context. If the count == 0 and the
+ * @token matches that stored in the current task context, return to the
+ * top level profile.
+ *
+ * change_hat only applies to profiles in the current ns, and each profile
+ * in the ns must make the same transition otherwise change_hat will fail.
+ */
+int aa_change_hat(const char *hats[], int count, u64 token, int flags)
+{
+ const struct cred *cred;
+ struct aa_task_ctx *ctx;
+ struct aa_label *label, *previous, *new = NULL, *target = NULL;
+ struct aa_profile *profile;
+ struct aa_perms perms = {};
+ const char *info = NULL;
+ int error = 0;
+
+ /*
+ * Fail explicitly requested domain transitions if no_new_privs.
+ * There is no exception for unconfined as change_hat is not
+ * available.
+ */
+ if (task_no_new_privs(current)) {
+ /* not an apparmor denial per se, so don't log it */
+ AA_DEBUG("no_new_privs - change_hat denied");
+ return -EPERM;
+ }
+
+ /* released below */
+ cred = get_current_cred();
+ ctx = cred_ctx(cred);
+ label = aa_get_newest_cred_label(cred);
+ previous = aa_get_newest_label(ctx->previous);
+
+ if (unconfined(label)) {
+ info = "unconfined can not change_hat";
+ error = -EPERM;
+ goto fail;
+ }
+
+ if (count) {
+ new = change_hat(label, hats, count, flags);
+ AA_BUG(!new);
+ if (IS_ERR(new)) {
+ error = PTR_ERR(new);
+ new = NULL;
+ /* already audited */
+ goto out;
+ }
+
+ error = may_change_ptraced_domain(new, &info);
+ if (error)
+ goto fail;
+
+ if (flags & AA_CHANGE_TEST)
+ goto out;
+
+ target = new;
+ error = aa_set_current_hat(new, token);
+ if (error == -EACCES)
+ /* kill task in case of brute force attacks */
+ goto kill;
+ } else if (previous && !(flags & AA_CHANGE_TEST)) {
+ /* Return to saved label. Kill task if restore fails
+ * to avoid brute force attacks
+ */
+ target = previous;
+ error = aa_restore_previous_label(token);
+ if (error) {
+ if (error == -EACCES)
+ goto kill;
+ goto fail;
+ }
+ } /* else ignore @flags && restores when there is no saved profile */
+
+out:
+ aa_put_label(new);
+ aa_put_label(previous);
+ aa_put_label(label);
+ put_cred(cred);
+
+ return error;
+
+kill:
+ info = "failed token match";
+ perms.kill = AA_MAY_CHANGEHAT;
+
+fail:
+ fn_for_each_in_ns(label, profile,
+ aa_audit_file(profile, &perms, OP_CHANGE_HAT,
+ AA_MAY_CHANGEHAT, NULL, NULL, target,
+ GLOBAL_ROOT_UID, info, error));
+
+ goto out;
+}
+
+
+static int change_profile_perms_wrapper(const char *op, const char *name,
+ struct aa_profile *profile,
+ struct aa_label *target, bool stack,
+ u32 request, struct aa_perms *perms)
+{
+ const char *info = NULL;
+ int error = 0;
+
+ /*
+ * Fail explicitly requested domain transitions when no_new_privs
+ * and not unconfined OR the transition results in a stack on
+ * the current label.
+ * Stacking domain transitions and transitions from unconfined are
+ * allowed even when no_new_privs is set because this aways results
+ * in a reduction of permissions.
+ */
+ if (task_no_new_privs(current) && !stack &&
+ !profile_unconfined(profile) &&
+ !aa_label_is_subset(target, &profile->label)) {
+ info = "no new privs";
+ error = -EPERM;
+ }
+
+ if (!error)
+ error = change_profile_perms(profile, target, stack, request,
+ profile->file.start, perms);
+ if (error)
+ error = aa_audit_file(profile, perms, op, request, name,
+ NULL, target, GLOBAL_ROOT_UID, info,
+ error);
+
+ return error;
+}
+
+/**
+ * aa_change_profile - perform a one-way profile transition
+ * @fqname: name of profile may include namespace (NOT NULL)
+ * @onexec: whether this transition is to take place immediately or at exec
+ * @flags: flags affecting change behavior
+ *
+ * Change to new profile @name. Unlike with hats, there is no way
+ * to change back. If @name isn't specified the current profile name is
+ * used.
+ * If @onexec then the transition is delayed until
+ * the next exec.
+ *
+ * Returns %0 on success, error otherwise.
+ */
+int aa_change_profile(const char *fqname, int flags)
+{
+ struct aa_label *label, *new = NULL, *target = NULL;
+ struct aa_profile *profile;
+ struct aa_perms perms = {};
+ const char *info = NULL;
+ const char *auditname = fqname; /* retain leading & if stack */
+ bool stack = flags & AA_CHANGE_STACK;
+ int error = 0;
+ char *op;
+ u32 request;
+
+ if (!fqname || !*fqname) {
+ AA_DEBUG("no profile name");
+ return -EINVAL;
+ }
+
+ if (flags & AA_CHANGE_ONEXEC) {
+ request = AA_MAY_ONEXEC;
+ if (stack)
+ op = OP_STACK_ONEXEC;
+ else
+ op = OP_CHANGE_ONEXEC;
+ } else {
+ request = AA_MAY_CHANGE_PROFILE;
+ if (stack)
+ op = OP_STACK;
+ else
+ op = OP_CHANGE_PROFILE;
+ }
+
+ label = aa_get_current_label();
+
+ if (*fqname == '&') {
+ stack = true;
+ /* don't have label_parse() do stacking */
+ fqname++;
+ }
+ target = aa_label_parse(label, fqname, GFP_KERNEL, true, false);
+ if (IS_ERR(target)) {
+ struct aa_profile *tprofile;
+
+ info = "label not found";
+ error = PTR_ERR(target);
+ target = NULL;
+ /*
+ * TODO: fixme using labels_profile is not right - do profile
+ * per complain profile
+ */
+ if ((flags & AA_CHANGE_TEST) ||
+ !COMPLAIN_MODE(labels_profile(label)))
+ goto audit;
+ /* released below */
+ tprofile = aa_new_null_profile(labels_profile(label), false,
+ fqname, GFP_KERNEL);
+ if (!tprofile) {
+ info = "failed null profile create";
+ error = -ENOMEM;
+ goto audit;
+ }
+ target = &tprofile->label;
+ goto check;
+ }
+
+ /*
+ * self directed transitions only apply to current policy ns
+ * TODO: currently requiring perms for stacking and straight change
+ * stacking doesn't strictly need this. Determine how much
+ * we want to loosen this restriction for stacking
+ *
+ * if (!stack) {
+ */
+ error = fn_for_each_in_ns(label, profile,
+ change_profile_perms_wrapper(op, auditname,
+ profile, target, stack,
+ request, &perms));
+ if (error)
+ /* auditing done in change_profile_perms_wrapper */
+ goto out;
+
+ /* } */
+
+check:
+ /* check if tracing task is allowed to trace target domain */
+ error = may_change_ptraced_domain(target, &info);
+ if (error && !fn_for_each_in_ns(label, profile,
+ COMPLAIN_MODE(profile)))
+ goto audit;
+
+ /* TODO: add permission check to allow this
+ * if ((flags & AA_CHANGE_ONEXEC) && !current_is_single_threaded()) {
+ * info = "not a single threaded task";
+ * error = -EACCES;
+ * goto audit;
+ * }
+ */
+ if (flags & AA_CHANGE_TEST)
+ goto out;
+
+ if (!(flags & AA_CHANGE_ONEXEC)) {
+ /* only transition profiles in the current ns */
+ if (stack)
+ new = aa_label_merge(label, target, GFP_KERNEL);
+ else
+ new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
+ aa_get_label(target),
+ aa_get_label(&profile->label));
+ if (IS_ERR_OR_NULL(new)) {
+ info = "failed to build target label";
+ if (!new)
+ error = -ENOMEM;
+ else
+ error = PTR_ERR(new);
+ new = NULL;
+ perms.allow = 0;
+ goto audit;
+ }
+ error = aa_replace_current_label(new);
+ } else
+ /* full transition will be built in exec path */
+ error = aa_set_current_onexec(target, stack);
+
+audit:
+ error = fn_for_each_in_ns(label, profile,
+ aa_audit_file(profile, &perms, op, request, auditname,
+ NULL, new ? new : target,
+ GLOBAL_ROOT_UID, info, error));
+
+out:
+ aa_put_label(new);
+ aa_put_label(target);
+ aa_put_label(label);
+
+ return error;
+}