forked from luck/tmp_suning_uos_patched
3a2dc8382a
2.6.36 introduced the abilitiy to specify the task that is having its rlimits set. Update mediation to ensure that confined tasks can only set their own group_leader as expected by current policy. Add TODO note about extending policy to support setting other tasks rlimits. Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
139 lines
3.9 KiB
C
139 lines
3.9 KiB
C
/*
|
|
* AppArmor security module
|
|
*
|
|
* This file contains AppArmor resource mediation and attachment
|
|
*
|
|
* Copyright (C) 1998-2008 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/audit.h>
|
|
|
|
#include "include/audit.h"
|
|
#include "include/resource.h"
|
|
#include "include/policy.h"
|
|
|
|
/*
|
|
* Table of rlimit names: we generate it from resource.h.
|
|
*/
|
|
#include "rlim_names.h"
|
|
|
|
/* audit callback for resource specific fields */
|
|
static void audit_cb(struct audit_buffer *ab, void *va)
|
|
{
|
|
struct common_audit_data *sa = va;
|
|
|
|
audit_log_format(ab, " rlimit=%s value=%lu",
|
|
rlim_names[sa->aad.rlim.rlim], sa->aad.rlim.max);
|
|
}
|
|
|
|
/**
|
|
* audit_resource - audit setting resource limit
|
|
* @profile: profile being enforced (NOT NULL)
|
|
* @resoure: rlimit being auditing
|
|
* @value: value being set
|
|
* @error: error value
|
|
*
|
|
* Returns: 0 or sa->error else other error code on failure
|
|
*/
|
|
static int audit_resource(struct aa_profile *profile, unsigned int resource,
|
|
unsigned long value, int error)
|
|
{
|
|
struct common_audit_data sa;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&sa, NONE);
|
|
sa.aad.op = OP_SETRLIMIT,
|
|
sa.aad.rlim.rlim = resource;
|
|
sa.aad.rlim.max = value;
|
|
sa.aad.error = error;
|
|
return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_KERNEL, &sa,
|
|
audit_cb);
|
|
}
|
|
|
|
/**
|
|
* aa_map_resouce - map compiled policy resource to internal #
|
|
* @resource: flattened policy resource number
|
|
*
|
|
* Returns: resource # for the current architecture.
|
|
*
|
|
* rlimit resource can vary based on architecture, map the compiled policy
|
|
* resource # to the internal representation for the architecture.
|
|
*/
|
|
int aa_map_resource(int resource)
|
|
{
|
|
return rlim_map[resource];
|
|
}
|
|
|
|
/**
|
|
* aa_task_setrlimit - test permission to set an rlimit
|
|
* @profile - profile confining the task (NOT NULL)
|
|
* @task - task the resource is being set on
|
|
* @resource - the resource being set
|
|
* @new_rlim - the new resource limit (NOT NULL)
|
|
*
|
|
* Control raising the processes hard limit.
|
|
*
|
|
* Returns: 0 or error code if setting resource failed
|
|
*/
|
|
int aa_task_setrlimit(struct aa_profile *profile, struct task_struct *task,
|
|
unsigned int resource, struct rlimit *new_rlim)
|
|
{
|
|
int error = 0;
|
|
|
|
/* TODO: extend resource control to handle other (non current)
|
|
* processes. AppArmor rules currently have the implicit assumption
|
|
* that the task is setting the resource of the current process
|
|
*/
|
|
if ((task != current->group_leader) ||
|
|
(profile->rlimits.mask & (1 << resource) &&
|
|
new_rlim->rlim_max > profile->rlimits.limits[resource].rlim_max))
|
|
error = -EACCES;
|
|
|
|
return audit_resource(profile, resource, new_rlim->rlim_max, error);
|
|
}
|
|
|
|
/**
|
|
* __aa_transition_rlimits - apply new profile rlimits
|
|
* @old: old profile on task (NOT NULL)
|
|
* @new: new profile with rlimits to apply (NOT NULL)
|
|
*/
|
|
void __aa_transition_rlimits(struct aa_profile *old, struct aa_profile *new)
|
|
{
|
|
unsigned int mask = 0;
|
|
struct rlimit *rlim, *initrlim;
|
|
int i;
|
|
|
|
/* for any rlimits the profile controlled reset the soft limit
|
|
* to the less of the tasks hard limit and the init tasks soft limit
|
|
*/
|
|
if (old->rlimits.mask) {
|
|
for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
|
|
if (old->rlimits.mask & mask) {
|
|
rlim = current->signal->rlim + i;
|
|
initrlim = init_task.signal->rlim + i;
|
|
rlim->rlim_cur = min(rlim->rlim_max,
|
|
initrlim->rlim_cur);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* set any new hard limits as dictated by the new profile */
|
|
if (!new->rlimits.mask)
|
|
return;
|
|
for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
|
|
if (!(new->rlimits.mask & mask))
|
|
continue;
|
|
|
|
rlim = current->signal->rlim + i;
|
|
rlim->rlim_max = min(rlim->rlim_max,
|
|
new->rlimits.limits[i].rlim_max);
|
|
/* soft limit should not exceed hard limit */
|
|
rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
|
|
}
|
|
}
|