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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor resource mediation and attachment
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11#include <linux/audit.h>
12#include <linux/security.h>
13
14#include "include/audit.h"
15#include "include/cred.h"
16#include "include/resource.h"
17#include "include/policy.h"
18
19/*
20 * Table of rlimit names: we generate it from resource.h.
21 */
22#include "rlim_names.h"
23
24struct aa_sfs_entry aa_sfs_entry_rlimit[] = {
25 AA_SFS_FILE_STRING("mask", AA_SFS_RLIMIT_MASK),
26 { }
27};
28
29/* audit callback for resource specific fields */
30static void audit_cb(struct audit_buffer *ab, void *va)
31{
32 struct common_audit_data *sa = va;
33
34 audit_log_format(ab, " rlimit=%s value=%lu",
35 rlim_names[aad(sa)->rlim.rlim], aad(sa)->rlim.max);
36 if (aad(sa)->peer) {
37 audit_log_format(ab, " peer=");
38 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
39 FLAGS_NONE, GFP_ATOMIC);
40 }
41}
42
43/**
44 * audit_resource - audit setting resource limit
45 * @profile: profile being enforced (NOT NULL)
46 * @resource: rlimit being auditing
47 * @value: value being set
48 * @error: error value
49 *
50 * Returns: 0 or sa->error else other error code on failure
51 */
52static int audit_resource(struct aa_profile *profile, unsigned int resource,
53 unsigned long value, struct aa_label *peer,
54 const char *info, int error)
55{
56 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETRLIMIT);
57
58 aad(&sa)->rlim.rlim = resource;
59 aad(&sa)->rlim.max = value;
60 aad(&sa)->peer = peer;
61 aad(&sa)->info = info;
62 aad(&sa)->error = error;
63
64 return aa_audit(AUDIT_APPARMOR_AUTO, profile, &sa, audit_cb);
65}
66
67/**
68 * aa_map_resouce - map compiled policy resource to internal #
69 * @resource: flattened policy resource number
70 *
71 * Returns: resource # for the current architecture.
72 *
73 * rlimit resource can vary based on architecture, map the compiled policy
74 * resource # to the internal representation for the architecture.
75 */
76int aa_map_resource(int resource)
77{
78 return rlim_map[resource];
79}
80
81static int profile_setrlimit(struct aa_profile *profile, unsigned int resource,
82 struct rlimit *new_rlim)
83{
84 int e = 0;
85
86 if (profile->rlimits.mask & (1 << resource) && new_rlim->rlim_max >
87 profile->rlimits.limits[resource].rlim_max)
88 e = -EACCES;
89 return audit_resource(profile, resource, new_rlim->rlim_max, NULL, NULL,
90 e);
91}
92
93/**
94 * aa_task_setrlimit - test permission to set an rlimit
95 * @label - label confining the task (NOT NULL)
96 * @task - task the resource is being set on
97 * @resource - the resource being set
98 * @new_rlim - the new resource limit (NOT NULL)
99 *
100 * Control raising the processes hard limit.
101 *
102 * Returns: 0 or error code if setting resource failed
103 */
104int aa_task_setrlimit(struct aa_label *label, struct task_struct *task,
105 unsigned int resource, struct rlimit *new_rlim)
106{
107 struct aa_profile *profile;
108 struct aa_label *peer;
109 int error = 0;
110
111 rcu_read_lock();
112 peer = aa_get_newest_cred_label(__task_cred(task));
113 rcu_read_unlock();
114
115 /* TODO: extend resource control to handle other (non current)
116 * profiles. AppArmor rules currently have the implicit assumption
117 * that the task is setting the resource of a task confined with
118 * the same profile or that the task setting the resource of another
119 * task has CAP_SYS_RESOURCE.
120 */
121
122 if (label != peer &&
123 aa_capable(label, CAP_SYS_RESOURCE, CAP_OPT_NOAUDIT) != 0)
124 error = fn_for_each(label, profile,
125 audit_resource(profile, resource,
126 new_rlim->rlim_max, peer,
127 "cap_sys_resource", -EACCES));
128 else
129 error = fn_for_each_confined(label, profile,
130 profile_setrlimit(profile, resource, new_rlim));
131 aa_put_label(peer);
132
133 return error;
134}
135
136/**
137 * __aa_transition_rlimits - apply new profile rlimits
138 * @old_l: old label on task (NOT NULL)
139 * @new_l: new label with rlimits to apply (NOT NULL)
140 */
141void __aa_transition_rlimits(struct aa_label *old_l, struct aa_label *new_l)
142{
143 unsigned int mask = 0;
144 struct rlimit *rlim, *initrlim;
145 struct aa_profile *old, *new;
146 struct label_it i;
147
148 old = labels_profile(old_l);
149 new = labels_profile(new_l);
150
151 /* for any rlimits the profile controlled, reset the soft limit
152 * to the lesser of the tasks hard limit and the init tasks soft limit
153 */
154 label_for_each_confined(i, old_l, old) {
155 if (old->rlimits.mask) {
156 int j;
157
158 for (j = 0, mask = 1; j < RLIM_NLIMITS; j++,
159 mask <<= 1) {
160 if (old->rlimits.mask & mask) {
161 rlim = current->signal->rlim + j;
162 initrlim = init_task.signal->rlim + j;
163 rlim->rlim_cur = min(rlim->rlim_max,
164 initrlim->rlim_cur);
165 }
166 }
167 }
168 }
169
170 /* set any new hard limits as dictated by the new profile */
171 label_for_each_confined(i, new_l, new) {
172 int j;
173
174 if (!new->rlimits.mask)
175 continue;
176 for (j = 0, mask = 1; j < RLIM_NLIMITS; j++, mask <<= 1) {
177 if (!(new->rlimits.mask & mask))
178 continue;
179
180 rlim = current->signal->rlim + j;
181 rlim->rlim_max = min(rlim->rlim_max,
182 new->rlimits.limits[j].rlim_max);
183 /* soft limit should not exceed hard limit */
184 rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
185 }
186 }
187}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor resource mediation and attachment
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11#include <linux/audit.h>
12#include <linux/security.h>
13
14#include "include/audit.h"
15#include "include/cred.h"
16#include "include/resource.h"
17#include "include/policy.h"
18
19/*
20 * Table of rlimit names: we generate it from resource.h.
21 */
22#include "rlim_names.h"
23
24struct aa_sfs_entry aa_sfs_entry_rlimit[] = {
25 AA_SFS_FILE_STRING("mask", AA_SFS_RLIMIT_MASK),
26 { }
27};
28
29/* audit callback for resource specific fields */
30static void audit_cb(struct audit_buffer *ab, void *va)
31{
32 struct common_audit_data *sa = va;
33
34 audit_log_format(ab, " rlimit=%s value=%lu",
35 rlim_names[aad(sa)->rlim.rlim], aad(sa)->rlim.max);
36 if (aad(sa)->peer) {
37 audit_log_format(ab, " peer=");
38 aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
39 FLAGS_NONE, GFP_ATOMIC);
40 }
41}
42
43/**
44 * audit_resource - audit setting resource limit
45 * @profile: profile being enforced (NOT NULL)
46 * @resource: rlimit being auditing
47 * @value: value being set
48 * @peer: aa_albel of the task being set
49 * @info: info being auditing
50 * @error: error value
51 *
52 * Returns: 0 or sa->error else other error code on failure
53 */
54static int audit_resource(struct aa_profile *profile, unsigned int resource,
55 unsigned long value, struct aa_label *peer,
56 const char *info, int error)
57{
58 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, AA_CLASS_RLIMITS,
59 OP_SETRLIMIT);
60
61 aad(&sa)->rlim.rlim = resource;
62 aad(&sa)->rlim.max = value;
63 aad(&sa)->peer = peer;
64 aad(&sa)->info = info;
65 aad(&sa)->error = error;
66
67 return aa_audit(AUDIT_APPARMOR_AUTO, profile, &sa, audit_cb);
68}
69
70/**
71 * aa_map_resource - map compiled policy resource to internal #
72 * @resource: flattened policy resource number
73 *
74 * Returns: resource # for the current architecture.
75 *
76 * rlimit resource can vary based on architecture, map the compiled policy
77 * resource # to the internal representation for the architecture.
78 */
79int aa_map_resource(int resource)
80{
81 return rlim_map[resource];
82}
83
84static int profile_setrlimit(struct aa_profile *profile, unsigned int resource,
85 struct rlimit *new_rlim)
86{
87 struct aa_ruleset *rules = list_first_entry(&profile->rules,
88 typeof(*rules), list);
89 int e = 0;
90
91 if (rules->rlimits.mask & (1 << resource) && new_rlim->rlim_max >
92 rules->rlimits.limits[resource].rlim_max)
93 e = -EACCES;
94 return audit_resource(profile, resource, new_rlim->rlim_max, NULL, NULL,
95 e);
96}
97
98/**
99 * aa_task_setrlimit - test permission to set an rlimit
100 * @label - label confining the task (NOT NULL)
101 * @task - task the resource is being set on
102 * @resource - the resource being set
103 * @new_rlim - the new resource limit (NOT NULL)
104 *
105 * Control raising the processes hard limit.
106 *
107 * Returns: 0 or error code if setting resource failed
108 */
109int aa_task_setrlimit(struct aa_label *label, struct task_struct *task,
110 unsigned int resource, struct rlimit *new_rlim)
111{
112 struct aa_profile *profile;
113 struct aa_label *peer;
114 int error = 0;
115
116 rcu_read_lock();
117 peer = aa_get_newest_cred_label(__task_cred(task));
118 rcu_read_unlock();
119
120 /* TODO: extend resource control to handle other (non current)
121 * profiles. AppArmor rules currently have the implicit assumption
122 * that the task is setting the resource of a task confined with
123 * the same profile or that the task setting the resource of another
124 * task has CAP_SYS_RESOURCE.
125 */
126
127 if (label != peer &&
128 aa_capable(label, CAP_SYS_RESOURCE, CAP_OPT_NOAUDIT) != 0)
129 error = fn_for_each(label, profile,
130 audit_resource(profile, resource,
131 new_rlim->rlim_max, peer,
132 "cap_sys_resource", -EACCES));
133 else
134 error = fn_for_each_confined(label, profile,
135 profile_setrlimit(profile, resource, new_rlim));
136 aa_put_label(peer);
137
138 return error;
139}
140
141/**
142 * __aa_transition_rlimits - apply new profile rlimits
143 * @old_l: old label on task (NOT NULL)
144 * @new_l: new label with rlimits to apply (NOT NULL)
145 */
146void __aa_transition_rlimits(struct aa_label *old_l, struct aa_label *new_l)
147{
148 unsigned int mask = 0;
149 struct rlimit *rlim, *initrlim;
150 struct aa_profile *old, *new;
151 struct label_it i;
152
153 old = labels_profile(old_l);
154 new = labels_profile(new_l);
155
156 /* for any rlimits the profile controlled, reset the soft limit
157 * to the lesser of the tasks hard limit and the init tasks soft limit
158 */
159 label_for_each_confined(i, old_l, old) {
160 struct aa_ruleset *rules = list_first_entry(&old->rules,
161 typeof(*rules),
162 list);
163 if (rules->rlimits.mask) {
164 int j;
165
166 for (j = 0, mask = 1; j < RLIM_NLIMITS; j++,
167 mask <<= 1) {
168 if (rules->rlimits.mask & mask) {
169 rlim = current->signal->rlim + j;
170 initrlim = init_task.signal->rlim + j;
171 rlim->rlim_cur = min(rlim->rlim_max,
172 initrlim->rlim_cur);
173 }
174 }
175 }
176 }
177
178 /* set any new hard limits as dictated by the new profile */
179 label_for_each_confined(i, new_l, new) {
180 struct aa_ruleset *rules = list_first_entry(&new->rules,
181 typeof(*rules),
182 list);
183 int j;
184
185 if (!rules->rlimits.mask)
186 continue;
187 for (j = 0, mask = 1; j < RLIM_NLIMITS; j++, mask <<= 1) {
188 if (!(rules->rlimits.mask & mask))
189 continue;
190
191 rlim = current->signal->rlim + j;
192 rlim->rlim_max = min(rlim->rlim_max,
193 rules->rlimits.limits[j].rlim_max);
194 /* soft limit should not exceed hard limit */
195 rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
196 }
197 }
198}