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1/*
2 * cn_proc.c - process events connector
3 *
4 * Copyright (C) Matt Helsley, IBM Corp. 2005
5 * Based on cn_fork.c by Guillaume Thouvenin <guillaume.thouvenin@bull.net>
6 * Original copyright notice follows:
7 * Copyright (C) 2005 BULL SA.
8 *
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24
25#include <linux/module.h>
26#include <linux/kernel.h>
27#include <linux/ktime.h>
28#include <linux/init.h>
29#include <linux/connector.h>
30#include <linux/gfp.h>
31#include <linux/ptrace.h>
32#include <linux/atomic.h>
33#include <linux/pid_namespace.h>
34
35#include <linux/cn_proc.h>
36
37/*
38 * Size of a cn_msg followed by a proc_event structure. Since the
39 * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
40 * add one 4-byte word to the size here, and then start the actual
41 * cn_msg structure 4 bytes into the stack buffer. The result is that
42 * the immediately following proc_event structure is aligned to 8 bytes.
43 */
44#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)
45
46/* See comment above; we test our assumption about sizeof struct cn_msg here. */
47static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)
48{
49 BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
50 return (struct cn_msg *)(buffer + 4);
51}
52
53static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
54static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
55
56/* proc_event_counts is used as the sequence number of the netlink message */
57static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
58
59static inline void get_seq(__u32 *ts, int *cpu)
60{
61 preempt_disable();
62 *ts = __this_cpu_inc_return(proc_event_counts) - 1;
63 *cpu = smp_processor_id();
64 preempt_enable();
65}
66
67void proc_fork_connector(struct task_struct *task)
68{
69 struct cn_msg *msg;
70 struct proc_event *ev;
71 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
72 struct timespec ts;
73 struct task_struct *parent;
74
75 if (atomic_read(&proc_event_num_listeners) < 1)
76 return;
77
78 msg = buffer_to_cn_msg(buffer);
79 ev = (struct proc_event *)msg->data;
80 memset(&ev->event_data, 0, sizeof(ev->event_data));
81 get_seq(&msg->seq, &ev->cpu);
82 ktime_get_ts(&ts); /* get high res monotonic timestamp */
83 ev->timestamp_ns = timespec_to_ns(&ts);
84 ev->what = PROC_EVENT_FORK;
85 rcu_read_lock();
86 parent = rcu_dereference(task->real_parent);
87 ev->event_data.fork.parent_pid = parent->pid;
88 ev->event_data.fork.parent_tgid = parent->tgid;
89 rcu_read_unlock();
90 ev->event_data.fork.child_pid = task->pid;
91 ev->event_data.fork.child_tgid = task->tgid;
92
93 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
94 msg->ack = 0; /* not used */
95 msg->len = sizeof(*ev);
96 msg->flags = 0; /* not used */
97 /* If cn_netlink_send() failed, the data is not sent */
98 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
99}
100
101void proc_exec_connector(struct task_struct *task)
102{
103 struct cn_msg *msg;
104 struct proc_event *ev;
105 struct timespec ts;
106 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
107
108 if (atomic_read(&proc_event_num_listeners) < 1)
109 return;
110
111 msg = buffer_to_cn_msg(buffer);
112 ev = (struct proc_event *)msg->data;
113 memset(&ev->event_data, 0, sizeof(ev->event_data));
114 get_seq(&msg->seq, &ev->cpu);
115 ktime_get_ts(&ts); /* get high res monotonic timestamp */
116 ev->timestamp_ns = timespec_to_ns(&ts);
117 ev->what = PROC_EVENT_EXEC;
118 ev->event_data.exec.process_pid = task->pid;
119 ev->event_data.exec.process_tgid = task->tgid;
120
121 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
122 msg->ack = 0; /* not used */
123 msg->len = sizeof(*ev);
124 msg->flags = 0; /* not used */
125 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
126}
127
128void proc_id_connector(struct task_struct *task, int which_id)
129{
130 struct cn_msg *msg;
131 struct proc_event *ev;
132 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
133 struct timespec ts;
134 const struct cred *cred;
135
136 if (atomic_read(&proc_event_num_listeners) < 1)
137 return;
138
139 msg = buffer_to_cn_msg(buffer);
140 ev = (struct proc_event *)msg->data;
141 memset(&ev->event_data, 0, sizeof(ev->event_data));
142 ev->what = which_id;
143 ev->event_data.id.process_pid = task->pid;
144 ev->event_data.id.process_tgid = task->tgid;
145 rcu_read_lock();
146 cred = __task_cred(task);
147 if (which_id == PROC_EVENT_UID) {
148 ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
149 ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
150 } else if (which_id == PROC_EVENT_GID) {
151 ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
152 ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
153 } else {
154 rcu_read_unlock();
155 return;
156 }
157 rcu_read_unlock();
158 get_seq(&msg->seq, &ev->cpu);
159 ktime_get_ts(&ts); /* get high res monotonic timestamp */
160 ev->timestamp_ns = timespec_to_ns(&ts);
161
162 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
163 msg->ack = 0; /* not used */
164 msg->len = sizeof(*ev);
165 msg->flags = 0; /* not used */
166 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
167}
168
169void proc_sid_connector(struct task_struct *task)
170{
171 struct cn_msg *msg;
172 struct proc_event *ev;
173 struct timespec ts;
174 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
175
176 if (atomic_read(&proc_event_num_listeners) < 1)
177 return;
178
179 msg = buffer_to_cn_msg(buffer);
180 ev = (struct proc_event *)msg->data;
181 memset(&ev->event_data, 0, sizeof(ev->event_data));
182 get_seq(&msg->seq, &ev->cpu);
183 ktime_get_ts(&ts); /* get high res monotonic timestamp */
184 ev->timestamp_ns = timespec_to_ns(&ts);
185 ev->what = PROC_EVENT_SID;
186 ev->event_data.sid.process_pid = task->pid;
187 ev->event_data.sid.process_tgid = task->tgid;
188
189 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
190 msg->ack = 0; /* not used */
191 msg->len = sizeof(*ev);
192 msg->flags = 0; /* not used */
193 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
194}
195
196void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
197{
198 struct cn_msg *msg;
199 struct proc_event *ev;
200 struct timespec ts;
201 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
202
203 if (atomic_read(&proc_event_num_listeners) < 1)
204 return;
205
206 msg = buffer_to_cn_msg(buffer);
207 ev = (struct proc_event *)msg->data;
208 memset(&ev->event_data, 0, sizeof(ev->event_data));
209 get_seq(&msg->seq, &ev->cpu);
210 ktime_get_ts(&ts); /* get high res monotonic timestamp */
211 ev->timestamp_ns = timespec_to_ns(&ts);
212 ev->what = PROC_EVENT_PTRACE;
213 ev->event_data.ptrace.process_pid = task->pid;
214 ev->event_data.ptrace.process_tgid = task->tgid;
215 if (ptrace_id == PTRACE_ATTACH) {
216 ev->event_data.ptrace.tracer_pid = current->pid;
217 ev->event_data.ptrace.tracer_tgid = current->tgid;
218 } else if (ptrace_id == PTRACE_DETACH) {
219 ev->event_data.ptrace.tracer_pid = 0;
220 ev->event_data.ptrace.tracer_tgid = 0;
221 } else
222 return;
223
224 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
225 msg->ack = 0; /* not used */
226 msg->len = sizeof(*ev);
227 msg->flags = 0; /* not used */
228 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
229}
230
231void proc_comm_connector(struct task_struct *task)
232{
233 struct cn_msg *msg;
234 struct proc_event *ev;
235 struct timespec ts;
236 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
237
238 if (atomic_read(&proc_event_num_listeners) < 1)
239 return;
240
241 msg = buffer_to_cn_msg(buffer);
242 ev = (struct proc_event *)msg->data;
243 memset(&ev->event_data, 0, sizeof(ev->event_data));
244 get_seq(&msg->seq, &ev->cpu);
245 ktime_get_ts(&ts); /* get high res monotonic timestamp */
246 ev->timestamp_ns = timespec_to_ns(&ts);
247 ev->what = PROC_EVENT_COMM;
248 ev->event_data.comm.process_pid = task->pid;
249 ev->event_data.comm.process_tgid = task->tgid;
250 get_task_comm(ev->event_data.comm.comm, task);
251
252 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
253 msg->ack = 0; /* not used */
254 msg->len = sizeof(*ev);
255 msg->flags = 0; /* not used */
256 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
257}
258
259void proc_coredump_connector(struct task_struct *task)
260{
261 struct cn_msg *msg;
262 struct proc_event *ev;
263 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
264 struct timespec ts;
265
266 if (atomic_read(&proc_event_num_listeners) < 1)
267 return;
268
269 msg = buffer_to_cn_msg(buffer);
270 ev = (struct proc_event *)msg->data;
271 memset(&ev->event_data, 0, sizeof(ev->event_data));
272 get_seq(&msg->seq, &ev->cpu);
273 ktime_get_ts(&ts); /* get high res monotonic timestamp */
274 ev->timestamp_ns = timespec_to_ns(&ts);
275 ev->what = PROC_EVENT_COREDUMP;
276 ev->event_data.coredump.process_pid = task->pid;
277 ev->event_data.coredump.process_tgid = task->tgid;
278
279 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
280 msg->ack = 0; /* not used */
281 msg->len = sizeof(*ev);
282 msg->flags = 0; /* not used */
283 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
284}
285
286void proc_exit_connector(struct task_struct *task)
287{
288 struct cn_msg *msg;
289 struct proc_event *ev;
290 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
291 struct timespec ts;
292
293 if (atomic_read(&proc_event_num_listeners) < 1)
294 return;
295
296 msg = buffer_to_cn_msg(buffer);
297 ev = (struct proc_event *)msg->data;
298 memset(&ev->event_data, 0, sizeof(ev->event_data));
299 get_seq(&msg->seq, &ev->cpu);
300 ktime_get_ts(&ts); /* get high res monotonic timestamp */
301 ev->timestamp_ns = timespec_to_ns(&ts);
302 ev->what = PROC_EVENT_EXIT;
303 ev->event_data.exit.process_pid = task->pid;
304 ev->event_data.exit.process_tgid = task->tgid;
305 ev->event_data.exit.exit_code = task->exit_code;
306 ev->event_data.exit.exit_signal = task->exit_signal;
307
308 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
309 msg->ack = 0; /* not used */
310 msg->len = sizeof(*ev);
311 msg->flags = 0; /* not used */
312 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
313}
314
315/*
316 * Send an acknowledgement message to userspace
317 *
318 * Use 0 for success, EFOO otherwise.
319 * Note: this is the negative of conventional kernel error
320 * values because it's not being returned via syscall return
321 * mechanisms.
322 */
323static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
324{
325 struct cn_msg *msg;
326 struct proc_event *ev;
327 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
328 struct timespec ts;
329
330 if (atomic_read(&proc_event_num_listeners) < 1)
331 return;
332
333 msg = buffer_to_cn_msg(buffer);
334 ev = (struct proc_event *)msg->data;
335 memset(&ev->event_data, 0, sizeof(ev->event_data));
336 msg->seq = rcvd_seq;
337 ktime_get_ts(&ts); /* get high res monotonic timestamp */
338 ev->timestamp_ns = timespec_to_ns(&ts);
339 ev->cpu = -1;
340 ev->what = PROC_EVENT_NONE;
341 ev->event_data.ack.err = err;
342 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
343 msg->ack = rcvd_ack + 1;
344 msg->len = sizeof(*ev);
345 msg->flags = 0; /* not used */
346 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
347}
348
349/**
350 * cn_proc_mcast_ctl
351 * @data: message sent from userspace via the connector
352 */
353static void cn_proc_mcast_ctl(struct cn_msg *msg,
354 struct netlink_skb_parms *nsp)
355{
356 enum proc_cn_mcast_op *mc_op = NULL;
357 int err = 0;
358
359 if (msg->len != sizeof(*mc_op))
360 return;
361
362 /*
363 * Events are reported with respect to the initial pid
364 * and user namespaces so ignore requestors from
365 * other namespaces.
366 */
367 if ((current_user_ns() != &init_user_ns) ||
368 (task_active_pid_ns(current) != &init_pid_ns))
369 return;
370
371 /* Can only change if privileged. */
372 if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
373 err = EPERM;
374 goto out;
375 }
376
377 mc_op = (enum proc_cn_mcast_op *)msg->data;
378 switch (*mc_op) {
379 case PROC_CN_MCAST_LISTEN:
380 atomic_inc(&proc_event_num_listeners);
381 break;
382 case PROC_CN_MCAST_IGNORE:
383 atomic_dec(&proc_event_num_listeners);
384 break;
385 default:
386 err = EINVAL;
387 break;
388 }
389
390out:
391 cn_proc_ack(err, msg->seq, msg->ack);
392}
393
394/*
395 * cn_proc_init - initialization entry point
396 *
397 * Adds the connector callback to the connector driver.
398 */
399static int __init cn_proc_init(void)
400{
401 int err = cn_add_callback(&cn_proc_event_id,
402 "cn_proc",
403 &cn_proc_mcast_ctl);
404 if (err) {
405 pr_warn("cn_proc failed to register\n");
406 return err;
407 }
408 return 0;
409}
410
411module_init(cn_proc_init);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * cn_proc.c - process events connector
4 *
5 * Copyright (C) Matt Helsley, IBM Corp. 2005
6 * Based on cn_fork.c by Guillaume Thouvenin <guillaume.thouvenin@bull.net>
7 * Original copyright notice follows:
8 * Copyright (C) 2005 BULL SA.
9 */
10
11#include <linux/kernel.h>
12#include <linux/ktime.h>
13#include <linux/init.h>
14#include <linux/connector.h>
15#include <linux/gfp.h>
16#include <linux/ptrace.h>
17#include <linux/atomic.h>
18#include <linux/pid_namespace.h>
19
20#include <linux/cn_proc.h>
21
22/*
23 * Size of a cn_msg followed by a proc_event structure. Since the
24 * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
25 * add one 4-byte word to the size here, and then start the actual
26 * cn_msg structure 4 bytes into the stack buffer. The result is that
27 * the immediately following proc_event structure is aligned to 8 bytes.
28 */
29#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)
30
31/* See comment above; we test our assumption about sizeof struct cn_msg here. */
32static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)
33{
34 BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
35 return (struct cn_msg *)(buffer + 4);
36}
37
38static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
39static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
40
41/* proc_event_counts is used as the sequence number of the netlink message */
42static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
43
44static inline void send_msg(struct cn_msg *msg)
45{
46 preempt_disable();
47
48 msg->seq = __this_cpu_inc_return(proc_event_counts) - 1;
49 ((struct proc_event *)msg->data)->cpu = smp_processor_id();
50
51 /*
52 * Preemption remains disabled during send to ensure the messages are
53 * ordered according to their sequence numbers.
54 *
55 * If cn_netlink_send() fails, the data is not sent.
56 */
57 cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT);
58
59 preempt_enable();
60}
61
62void proc_fork_connector(struct task_struct *task)
63{
64 struct cn_msg *msg;
65 struct proc_event *ev;
66 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
67 struct task_struct *parent;
68
69 if (atomic_read(&proc_event_num_listeners) < 1)
70 return;
71
72 msg = buffer_to_cn_msg(buffer);
73 ev = (struct proc_event *)msg->data;
74 memset(&ev->event_data, 0, sizeof(ev->event_data));
75 ev->timestamp_ns = ktime_get_ns();
76 ev->what = PROC_EVENT_FORK;
77 rcu_read_lock();
78 parent = rcu_dereference(task->real_parent);
79 ev->event_data.fork.parent_pid = parent->pid;
80 ev->event_data.fork.parent_tgid = parent->tgid;
81 rcu_read_unlock();
82 ev->event_data.fork.child_pid = task->pid;
83 ev->event_data.fork.child_tgid = task->tgid;
84
85 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
86 msg->ack = 0; /* not used */
87 msg->len = sizeof(*ev);
88 msg->flags = 0; /* not used */
89 send_msg(msg);
90}
91
92void proc_exec_connector(struct task_struct *task)
93{
94 struct cn_msg *msg;
95 struct proc_event *ev;
96 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
97
98 if (atomic_read(&proc_event_num_listeners) < 1)
99 return;
100
101 msg = buffer_to_cn_msg(buffer);
102 ev = (struct proc_event *)msg->data;
103 memset(&ev->event_data, 0, sizeof(ev->event_data));
104 ev->timestamp_ns = ktime_get_ns();
105 ev->what = PROC_EVENT_EXEC;
106 ev->event_data.exec.process_pid = task->pid;
107 ev->event_data.exec.process_tgid = task->tgid;
108
109 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
110 msg->ack = 0; /* not used */
111 msg->len = sizeof(*ev);
112 msg->flags = 0; /* not used */
113 send_msg(msg);
114}
115
116void proc_id_connector(struct task_struct *task, int which_id)
117{
118 struct cn_msg *msg;
119 struct proc_event *ev;
120 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
121 const struct cred *cred;
122
123 if (atomic_read(&proc_event_num_listeners) < 1)
124 return;
125
126 msg = buffer_to_cn_msg(buffer);
127 ev = (struct proc_event *)msg->data;
128 memset(&ev->event_data, 0, sizeof(ev->event_data));
129 ev->what = which_id;
130 ev->event_data.id.process_pid = task->pid;
131 ev->event_data.id.process_tgid = task->tgid;
132 rcu_read_lock();
133 cred = __task_cred(task);
134 if (which_id == PROC_EVENT_UID) {
135 ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
136 ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
137 } else if (which_id == PROC_EVENT_GID) {
138 ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
139 ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
140 } else {
141 rcu_read_unlock();
142 return;
143 }
144 rcu_read_unlock();
145 ev->timestamp_ns = ktime_get_ns();
146
147 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
148 msg->ack = 0; /* not used */
149 msg->len = sizeof(*ev);
150 msg->flags = 0; /* not used */
151 send_msg(msg);
152}
153
154void proc_sid_connector(struct task_struct *task)
155{
156 struct cn_msg *msg;
157 struct proc_event *ev;
158 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
159
160 if (atomic_read(&proc_event_num_listeners) < 1)
161 return;
162
163 msg = buffer_to_cn_msg(buffer);
164 ev = (struct proc_event *)msg->data;
165 memset(&ev->event_data, 0, sizeof(ev->event_data));
166 ev->timestamp_ns = ktime_get_ns();
167 ev->what = PROC_EVENT_SID;
168 ev->event_data.sid.process_pid = task->pid;
169 ev->event_data.sid.process_tgid = task->tgid;
170
171 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
172 msg->ack = 0; /* not used */
173 msg->len = sizeof(*ev);
174 msg->flags = 0; /* not used */
175 send_msg(msg);
176}
177
178void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
179{
180 struct cn_msg *msg;
181 struct proc_event *ev;
182 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
183
184 if (atomic_read(&proc_event_num_listeners) < 1)
185 return;
186
187 msg = buffer_to_cn_msg(buffer);
188 ev = (struct proc_event *)msg->data;
189 memset(&ev->event_data, 0, sizeof(ev->event_data));
190 ev->timestamp_ns = ktime_get_ns();
191 ev->what = PROC_EVENT_PTRACE;
192 ev->event_data.ptrace.process_pid = task->pid;
193 ev->event_data.ptrace.process_tgid = task->tgid;
194 if (ptrace_id == PTRACE_ATTACH) {
195 ev->event_data.ptrace.tracer_pid = current->pid;
196 ev->event_data.ptrace.tracer_tgid = current->tgid;
197 } else if (ptrace_id == PTRACE_DETACH) {
198 ev->event_data.ptrace.tracer_pid = 0;
199 ev->event_data.ptrace.tracer_tgid = 0;
200 } else
201 return;
202
203 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
204 msg->ack = 0; /* not used */
205 msg->len = sizeof(*ev);
206 msg->flags = 0; /* not used */
207 send_msg(msg);
208}
209
210void proc_comm_connector(struct task_struct *task)
211{
212 struct cn_msg *msg;
213 struct proc_event *ev;
214 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
215
216 if (atomic_read(&proc_event_num_listeners) < 1)
217 return;
218
219 msg = buffer_to_cn_msg(buffer);
220 ev = (struct proc_event *)msg->data;
221 memset(&ev->event_data, 0, sizeof(ev->event_data));
222 ev->timestamp_ns = ktime_get_ns();
223 ev->what = PROC_EVENT_COMM;
224 ev->event_data.comm.process_pid = task->pid;
225 ev->event_data.comm.process_tgid = task->tgid;
226 get_task_comm(ev->event_data.comm.comm, task);
227
228 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
229 msg->ack = 0; /* not used */
230 msg->len = sizeof(*ev);
231 msg->flags = 0; /* not used */
232 send_msg(msg);
233}
234
235void proc_coredump_connector(struct task_struct *task)
236{
237 struct cn_msg *msg;
238 struct proc_event *ev;
239 struct task_struct *parent;
240 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
241
242 if (atomic_read(&proc_event_num_listeners) < 1)
243 return;
244
245 msg = buffer_to_cn_msg(buffer);
246 ev = (struct proc_event *)msg->data;
247 memset(&ev->event_data, 0, sizeof(ev->event_data));
248 ev->timestamp_ns = ktime_get_ns();
249 ev->what = PROC_EVENT_COREDUMP;
250 ev->event_data.coredump.process_pid = task->pid;
251 ev->event_data.coredump.process_tgid = task->tgid;
252
253 rcu_read_lock();
254 if (pid_alive(task)) {
255 parent = rcu_dereference(task->real_parent);
256 ev->event_data.coredump.parent_pid = parent->pid;
257 ev->event_data.coredump.parent_tgid = parent->tgid;
258 }
259 rcu_read_unlock();
260
261 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
262 msg->ack = 0; /* not used */
263 msg->len = sizeof(*ev);
264 msg->flags = 0; /* not used */
265 send_msg(msg);
266}
267
268void proc_exit_connector(struct task_struct *task)
269{
270 struct cn_msg *msg;
271 struct proc_event *ev;
272 struct task_struct *parent;
273 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
274
275 if (atomic_read(&proc_event_num_listeners) < 1)
276 return;
277
278 msg = buffer_to_cn_msg(buffer);
279 ev = (struct proc_event *)msg->data;
280 memset(&ev->event_data, 0, sizeof(ev->event_data));
281 ev->timestamp_ns = ktime_get_ns();
282 ev->what = PROC_EVENT_EXIT;
283 ev->event_data.exit.process_pid = task->pid;
284 ev->event_data.exit.process_tgid = task->tgid;
285 ev->event_data.exit.exit_code = task->exit_code;
286 ev->event_data.exit.exit_signal = task->exit_signal;
287
288 rcu_read_lock();
289 if (pid_alive(task)) {
290 parent = rcu_dereference(task->real_parent);
291 ev->event_data.exit.parent_pid = parent->pid;
292 ev->event_data.exit.parent_tgid = parent->tgid;
293 }
294 rcu_read_unlock();
295
296 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
297 msg->ack = 0; /* not used */
298 msg->len = sizeof(*ev);
299 msg->flags = 0; /* not used */
300 send_msg(msg);
301}
302
303/*
304 * Send an acknowledgement message to userspace
305 *
306 * Use 0 for success, EFOO otherwise.
307 * Note: this is the negative of conventional kernel error
308 * values because it's not being returned via syscall return
309 * mechanisms.
310 */
311static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
312{
313 struct cn_msg *msg;
314 struct proc_event *ev;
315 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
316
317 if (atomic_read(&proc_event_num_listeners) < 1)
318 return;
319
320 msg = buffer_to_cn_msg(buffer);
321 ev = (struct proc_event *)msg->data;
322 memset(&ev->event_data, 0, sizeof(ev->event_data));
323 msg->seq = rcvd_seq;
324 ev->timestamp_ns = ktime_get_ns();
325 ev->cpu = -1;
326 ev->what = PROC_EVENT_NONE;
327 ev->event_data.ack.err = err;
328 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
329 msg->ack = rcvd_ack + 1;
330 msg->len = sizeof(*ev);
331 msg->flags = 0; /* not used */
332 send_msg(msg);
333}
334
335/**
336 * cn_proc_mcast_ctl
337 * @data: message sent from userspace via the connector
338 */
339static void cn_proc_mcast_ctl(struct cn_msg *msg,
340 struct netlink_skb_parms *nsp)
341{
342 enum proc_cn_mcast_op *mc_op = NULL;
343 int err = 0;
344
345 if (msg->len != sizeof(*mc_op))
346 return;
347
348 /*
349 * Events are reported with respect to the initial pid
350 * and user namespaces so ignore requestors from
351 * other namespaces.
352 */
353 if ((current_user_ns() != &init_user_ns) ||
354 (task_active_pid_ns(current) != &init_pid_ns))
355 return;
356
357 /* Can only change if privileged. */
358 if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
359 err = EPERM;
360 goto out;
361 }
362
363 mc_op = (enum proc_cn_mcast_op *)msg->data;
364 switch (*mc_op) {
365 case PROC_CN_MCAST_LISTEN:
366 atomic_inc(&proc_event_num_listeners);
367 break;
368 case PROC_CN_MCAST_IGNORE:
369 atomic_dec(&proc_event_num_listeners);
370 break;
371 default:
372 err = EINVAL;
373 break;
374 }
375
376out:
377 cn_proc_ack(err, msg->seq, msg->ack);
378}
379
380/*
381 * cn_proc_init - initialization entry point
382 *
383 * Adds the connector callback to the connector driver.
384 */
385static int __init cn_proc_init(void)
386{
387 int err = cn_add_callback(&cn_proc_event_id,
388 "cn_proc",
389 &cn_proc_mcast_ctl);
390 if (err) {
391 pr_warn("cn_proc failed to register\n");
392 return err;
393 }
394 return 0;
395}
396device_initcall(cn_proc_init);