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v6.13.7
  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#include <linux/local_lock.h>
 22
 23/*
 24 * Size of a cn_msg followed by a proc_event structure.  Since the
 25 * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
 26 * add one 4-byte word to the size here, and then start the actual
 27 * cn_msg structure 4 bytes into the stack buffer.  The result is that
 28 * the immediately following proc_event structure is aligned to 8 bytes.
 29 */
 30#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)
 31
 32/* See comment above; we test our assumption about sizeof struct cn_msg here. */
 33static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)
 34{
 35	BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
 36	return (struct cn_msg *)(buffer + 4);
 37}
 38
 39static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
 40static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
 41
 42/* local_event.count is used as the sequence number of the netlink message */
 43struct local_event {
 44	local_lock_t lock;
 45	__u32 count;
 46};
 47static DEFINE_PER_CPU(struct local_event, local_event) = {
 48	.lock = INIT_LOCAL_LOCK(lock),
 49};
 50
 51static int cn_filter(struct sock *dsk, struct sk_buff *skb, void *data)
 52{
 53	__u32 what, exit_code, *ptr;
 54	enum proc_cn_mcast_op mc_op;
 55	uintptr_t val;
 56
 57	if (!dsk || !dsk->sk_user_data || !data)
 58		return 0;
 59
 60	ptr = (__u32 *)data;
 61	what = *ptr++;
 62	exit_code = *ptr;
 63	val = ((struct proc_input *)(dsk->sk_user_data))->event_type;
 64	mc_op = ((struct proc_input *)(dsk->sk_user_data))->mcast_op;
 65
 66	if (mc_op == PROC_CN_MCAST_IGNORE)
 67		return 1;
 68
 69	if ((__u32)val == PROC_EVENT_ALL)
 70		return 0;
 71
 72	/*
 73	 * Drop packet if we have to report only non-zero exit status
 74	 * (PROC_EVENT_NONZERO_EXIT) and exit status is 0
 75	 */
 76	if (((__u32)val & PROC_EVENT_NONZERO_EXIT) &&
 77	    (what == PROC_EVENT_EXIT)) {
 78		if (exit_code)
 79			return 0;
 80	}
 81
 82	if ((__u32)val & what)
 83		return 0;
 84
 85	return 1;
 86}
 87
 88static inline void send_msg(struct cn_msg *msg)
 89{
 90	__u32 filter_data[2];
 91
 92	local_lock(&local_event.lock);
 93
 94	msg->seq = __this_cpu_inc_return(local_event.count) - 1;
 95	((struct proc_event *)msg->data)->cpu = smp_processor_id();
 96
 97	/*
 98	 * local_lock() disables preemption during send to ensure the messages
 99	 * are ordered according to their sequence numbers.
100	 *
101	 * If cn_netlink_send() fails, the data is not sent.
102	 */
103	filter_data[0] = ((struct proc_event *)msg->data)->what;
104	if (filter_data[0] == PROC_EVENT_EXIT) {
105		filter_data[1] =
106		((struct proc_event *)msg->data)->event_data.exit.exit_code;
107	} else {
108		filter_data[1] = 0;
109	}
110
111	cn_netlink_send_mult(msg, msg->len, 0, CN_IDX_PROC, GFP_NOWAIT,
112			     cn_filter, (void *)filter_data);
113
114	local_unlock(&local_event.lock);
115}
116
117void proc_fork_connector(struct task_struct *task)
118{
119	struct cn_msg *msg;
120	struct proc_event *ev;
121	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
122	struct task_struct *parent;
123
124	if (atomic_read(&proc_event_num_listeners) < 1)
125		return;
126
127	msg = buffer_to_cn_msg(buffer);
128	ev = (struct proc_event *)msg->data;
129	memset(&ev->event_data, 0, sizeof(ev->event_data));
 
130	ev->timestamp_ns = ktime_get_ns();
131	ev->what = PROC_EVENT_FORK;
132	rcu_read_lock();
133	parent = rcu_dereference(task->real_parent);
134	ev->event_data.fork.parent_pid = parent->pid;
135	ev->event_data.fork.parent_tgid = parent->tgid;
136	rcu_read_unlock();
137	ev->event_data.fork.child_pid = task->pid;
138	ev->event_data.fork.child_tgid = task->tgid;
139
140	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
141	msg->ack = 0; /* not used */
142	msg->len = sizeof(*ev);
143	msg->flags = 0; /* not used */
144	send_msg(msg);
 
145}
146
147void proc_exec_connector(struct task_struct *task)
148{
149	struct cn_msg *msg;
150	struct proc_event *ev;
151	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
152
153	if (atomic_read(&proc_event_num_listeners) < 1)
154		return;
155
156	msg = buffer_to_cn_msg(buffer);
157	ev = (struct proc_event *)msg->data;
158	memset(&ev->event_data, 0, sizeof(ev->event_data));
 
159	ev->timestamp_ns = ktime_get_ns();
160	ev->what = PROC_EVENT_EXEC;
161	ev->event_data.exec.process_pid = task->pid;
162	ev->event_data.exec.process_tgid = task->tgid;
163
164	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
165	msg->ack = 0; /* not used */
166	msg->len = sizeof(*ev);
167	msg->flags = 0; /* not used */
168	send_msg(msg);
169}
170
171void proc_id_connector(struct task_struct *task, int which_id)
172{
173	struct cn_msg *msg;
174	struct proc_event *ev;
175	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
176	const struct cred *cred;
177
178	if (atomic_read(&proc_event_num_listeners) < 1)
179		return;
180
181	msg = buffer_to_cn_msg(buffer);
182	ev = (struct proc_event *)msg->data;
183	memset(&ev->event_data, 0, sizeof(ev->event_data));
184	ev->what = which_id;
185	ev->event_data.id.process_pid = task->pid;
186	ev->event_data.id.process_tgid = task->tgid;
187	rcu_read_lock();
188	cred = __task_cred(task);
189	if (which_id == PROC_EVENT_UID) {
190		ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
191		ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
192	} else if (which_id == PROC_EVENT_GID) {
193		ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
194		ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
195	} else {
196		rcu_read_unlock();
197		return;
198	}
199	rcu_read_unlock();
 
200	ev->timestamp_ns = ktime_get_ns();
201
202	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
203	msg->ack = 0; /* not used */
204	msg->len = sizeof(*ev);
205	msg->flags = 0; /* not used */
206	send_msg(msg);
207}
208
209void proc_sid_connector(struct task_struct *task)
210{
211	struct cn_msg *msg;
212	struct proc_event *ev;
213	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
214
215	if (atomic_read(&proc_event_num_listeners) < 1)
216		return;
217
218	msg = buffer_to_cn_msg(buffer);
219	ev = (struct proc_event *)msg->data;
220	memset(&ev->event_data, 0, sizeof(ev->event_data));
 
221	ev->timestamp_ns = ktime_get_ns();
222	ev->what = PROC_EVENT_SID;
223	ev->event_data.sid.process_pid = task->pid;
224	ev->event_data.sid.process_tgid = task->tgid;
225
226	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
227	msg->ack = 0; /* not used */
228	msg->len = sizeof(*ev);
229	msg->flags = 0; /* not used */
230	send_msg(msg);
231}
232
233void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
234{
235	struct cn_msg *msg;
236	struct proc_event *ev;
237	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
238
239	if (atomic_read(&proc_event_num_listeners) < 1)
240		return;
241
242	msg = buffer_to_cn_msg(buffer);
243	ev = (struct proc_event *)msg->data;
244	memset(&ev->event_data, 0, sizeof(ev->event_data));
 
245	ev->timestamp_ns = ktime_get_ns();
246	ev->what = PROC_EVENT_PTRACE;
247	ev->event_data.ptrace.process_pid  = task->pid;
248	ev->event_data.ptrace.process_tgid = task->tgid;
249	if (ptrace_id == PTRACE_ATTACH) {
250		ev->event_data.ptrace.tracer_pid  = current->pid;
251		ev->event_data.ptrace.tracer_tgid = current->tgid;
252	} else if (ptrace_id == PTRACE_DETACH) {
253		ev->event_data.ptrace.tracer_pid  = 0;
254		ev->event_data.ptrace.tracer_tgid = 0;
255	} else
256		return;
257
258	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
259	msg->ack = 0; /* not used */
260	msg->len = sizeof(*ev);
261	msg->flags = 0; /* not used */
262	send_msg(msg);
263}
264
265void proc_comm_connector(struct task_struct *task)
266{
267	struct cn_msg *msg;
268	struct proc_event *ev;
269	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
270
271	if (atomic_read(&proc_event_num_listeners) < 1)
272		return;
273
274	msg = buffer_to_cn_msg(buffer);
275	ev = (struct proc_event *)msg->data;
276	memset(&ev->event_data, 0, sizeof(ev->event_data));
 
277	ev->timestamp_ns = ktime_get_ns();
278	ev->what = PROC_EVENT_COMM;
279	ev->event_data.comm.process_pid  = task->pid;
280	ev->event_data.comm.process_tgid = task->tgid;
281	get_task_comm(ev->event_data.comm.comm, task);
282
283	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
284	msg->ack = 0; /* not used */
285	msg->len = sizeof(*ev);
286	msg->flags = 0; /* not used */
287	send_msg(msg);
288}
289
290void proc_coredump_connector(struct task_struct *task)
291{
292	struct cn_msg *msg;
293	struct proc_event *ev;
294	struct task_struct *parent;
295	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
296
297	if (atomic_read(&proc_event_num_listeners) < 1)
298		return;
299
300	msg = buffer_to_cn_msg(buffer);
301	ev = (struct proc_event *)msg->data;
302	memset(&ev->event_data, 0, sizeof(ev->event_data));
 
303	ev->timestamp_ns = ktime_get_ns();
304	ev->what = PROC_EVENT_COREDUMP;
305	ev->event_data.coredump.process_pid = task->pid;
306	ev->event_data.coredump.process_tgid = task->tgid;
307
308	rcu_read_lock();
309	if (pid_alive(task)) {
310		parent = rcu_dereference(task->real_parent);
311		ev->event_data.coredump.parent_pid = parent->pid;
312		ev->event_data.coredump.parent_tgid = parent->tgid;
313	}
314	rcu_read_unlock();
315
316	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
317	msg->ack = 0; /* not used */
318	msg->len = sizeof(*ev);
319	msg->flags = 0; /* not used */
320	send_msg(msg);
321}
322
323void proc_exit_connector(struct task_struct *task)
324{
325	struct cn_msg *msg;
326	struct proc_event *ev;
327	struct task_struct *parent;
328	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
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	ev->timestamp_ns = ktime_get_ns();
337	ev->what = PROC_EVENT_EXIT;
338	ev->event_data.exit.process_pid = task->pid;
339	ev->event_data.exit.process_tgid = task->tgid;
340	ev->event_data.exit.exit_code = task->exit_code;
341	ev->event_data.exit.exit_signal = task->exit_signal;
342
343	rcu_read_lock();
344	if (pid_alive(task)) {
345		parent = rcu_dereference(task->real_parent);
346		ev->event_data.exit.parent_pid = parent->pid;
347		ev->event_data.exit.parent_tgid = parent->tgid;
348	}
349	rcu_read_unlock();
350
351	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
352	msg->ack = 0; /* not used */
353	msg->len = sizeof(*ev);
354	msg->flags = 0; /* not used */
355	send_msg(msg);
356}
357
358/*
359 * Send an acknowledgement message to userspace
360 *
361 * Use 0 for success, EFOO otherwise.
362 * Note: this is the negative of conventional kernel error
363 * values because it's not being returned via syscall return
364 * mechanisms.
365 */
366static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
367{
368	struct cn_msg *msg;
369	struct proc_event *ev;
370	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
371
372	if (atomic_read(&proc_event_num_listeners) < 1)
373		return;
374
375	msg = buffer_to_cn_msg(buffer);
376	ev = (struct proc_event *)msg->data;
377	memset(&ev->event_data, 0, sizeof(ev->event_data));
378	msg->seq = rcvd_seq;
379	ev->timestamp_ns = ktime_get_ns();
380	ev->cpu = -1;
381	ev->what = PROC_EVENT_NONE;
382	ev->event_data.ack.err = err;
383	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
384	msg->ack = rcvd_ack + 1;
385	msg->len = sizeof(*ev);
386	msg->flags = 0; /* not used */
387	send_msg(msg);
388}
389
390/**
391 * cn_proc_mcast_ctl
392 * @msg: message sent from userspace via the connector
393 * @nsp: NETLINK_CB of the client's socket buffer
394 */
395static void cn_proc_mcast_ctl(struct cn_msg *msg,
396			      struct netlink_skb_parms *nsp)
397{
398	enum proc_cn_mcast_op mc_op = 0, prev_mc_op = 0;
399	struct proc_input *pinput = NULL;
400	enum proc_cn_event ev_type = 0;
401	int err = 0, initial = 0;
402	struct sock *sk = NULL;
403
404	/* 
405	 * Events are reported with respect to the initial pid
406	 * and user namespaces so ignore requestors from
407	 * other namespaces.
408	 */
409	if ((current_user_ns() != &init_user_ns) ||
410	    !task_is_in_init_pid_ns(current))
411		return;
412
413	if (msg->len == sizeof(*pinput)) {
414		pinput = (struct proc_input *)msg->data;
415		mc_op = pinput->mcast_op;
416		ev_type = pinput->event_type;
417	} else if (msg->len == sizeof(mc_op)) {
418		mc_op = *((enum proc_cn_mcast_op *)msg->data);
419		ev_type = PROC_EVENT_ALL;
420	} else {
421		return;
422	}
423
424	ev_type = valid_event((enum proc_cn_event)ev_type);
425
426	if (ev_type == PROC_EVENT_NONE)
427		ev_type = PROC_EVENT_ALL;
428
429	if (nsp->sk) {
430		sk = nsp->sk;
431		if (sk->sk_user_data == NULL) {
432			sk->sk_user_data = kzalloc(sizeof(struct proc_input),
433						   GFP_KERNEL);
434			if (sk->sk_user_data == NULL) {
435				err = ENOMEM;
436				goto out;
437			}
438			initial = 1;
439		} else {
440			prev_mc_op =
441			((struct proc_input *)(sk->sk_user_data))->mcast_op;
442		}
443		((struct proc_input *)(sk->sk_user_data))->event_type =
444			ev_type;
445		((struct proc_input *)(sk->sk_user_data))->mcast_op = mc_op;
446	}
447
448	switch (mc_op) {
449	case PROC_CN_MCAST_LISTEN:
450		if (initial || (prev_mc_op != PROC_CN_MCAST_LISTEN))
451			atomic_inc(&proc_event_num_listeners);
452		break;
453	case PROC_CN_MCAST_IGNORE:
454		if (!initial && (prev_mc_op != PROC_CN_MCAST_IGNORE))
455			atomic_dec(&proc_event_num_listeners);
456		((struct proc_input *)(sk->sk_user_data))->event_type =
457			PROC_EVENT_NONE;
458		break;
459	default:
460		err = EINVAL;
461		break;
462	}
463
464out:
465	cn_proc_ack(err, msg->seq, msg->ack);
466}
467
468/*
469 * cn_proc_init - initialization entry point
470 *
471 * Adds the connector callback to the connector driver.
472 */
473static int __init cn_proc_init(void)
474{
475	int err = cn_add_callback(&cn_proc_event_id,
476				  "cn_proc",
477				  &cn_proc_mcast_ctl);
478	if (err) {
479		pr_warn("cn_proc failed to register\n");
480		return err;
481	}
482	return 0;
483}
484device_initcall(cn_proc_init);
 
v4.6
 
  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 task_struct *parent;
 73
 74	if (atomic_read(&proc_event_num_listeners) < 1)
 75		return;
 76
 77	msg = buffer_to_cn_msg(buffer);
 78	ev = (struct proc_event *)msg->data;
 79	memset(&ev->event_data, 0, sizeof(ev->event_data));
 80	get_seq(&msg->seq, &ev->cpu);
 81	ev->timestamp_ns = ktime_get_ns();
 82	ev->what = PROC_EVENT_FORK;
 83	rcu_read_lock();
 84	parent = rcu_dereference(task->real_parent);
 85	ev->event_data.fork.parent_pid = parent->pid;
 86	ev->event_data.fork.parent_tgid = parent->tgid;
 87	rcu_read_unlock();
 88	ev->event_data.fork.child_pid = task->pid;
 89	ev->event_data.fork.child_tgid = task->tgid;
 90
 91	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
 92	msg->ack = 0; /* not used */
 93	msg->len = sizeof(*ev);
 94	msg->flags = 0; /* not used */
 95	/*  If cn_netlink_send() failed, the data is not sent */
 96	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 97}
 98
 99void proc_exec_connector(struct task_struct *task)
100{
101	struct cn_msg *msg;
102	struct proc_event *ev;
103	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
104
105	if (atomic_read(&proc_event_num_listeners) < 1)
106		return;
107
108	msg = buffer_to_cn_msg(buffer);
109	ev = (struct proc_event *)msg->data;
110	memset(&ev->event_data, 0, sizeof(ev->event_data));
111	get_seq(&msg->seq, &ev->cpu);
112	ev->timestamp_ns = ktime_get_ns();
113	ev->what = PROC_EVENT_EXEC;
114	ev->event_data.exec.process_pid = task->pid;
115	ev->event_data.exec.process_tgid = task->tgid;
116
117	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
118	msg->ack = 0; /* not used */
119	msg->len = sizeof(*ev);
120	msg->flags = 0; /* not used */
121	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
122}
123
124void proc_id_connector(struct task_struct *task, int which_id)
125{
126	struct cn_msg *msg;
127	struct proc_event *ev;
128	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
129	const struct cred *cred;
130
131	if (atomic_read(&proc_event_num_listeners) < 1)
132		return;
133
134	msg = buffer_to_cn_msg(buffer);
135	ev = (struct proc_event *)msg->data;
136	memset(&ev->event_data, 0, sizeof(ev->event_data));
137	ev->what = which_id;
138	ev->event_data.id.process_pid = task->pid;
139	ev->event_data.id.process_tgid = task->tgid;
140	rcu_read_lock();
141	cred = __task_cred(task);
142	if (which_id == PROC_EVENT_UID) {
143		ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
144		ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
145	} else if (which_id == PROC_EVENT_GID) {
146		ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
147		ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
148	} else {
149		rcu_read_unlock();
150		return;
151	}
152	rcu_read_unlock();
153	get_seq(&msg->seq, &ev->cpu);
154	ev->timestamp_ns = ktime_get_ns();
155
156	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
157	msg->ack = 0; /* not used */
158	msg->len = sizeof(*ev);
159	msg->flags = 0; /* not used */
160	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
161}
162
163void proc_sid_connector(struct task_struct *task)
164{
165	struct cn_msg *msg;
166	struct proc_event *ev;
167	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
168
169	if (atomic_read(&proc_event_num_listeners) < 1)
170		return;
171
172	msg = buffer_to_cn_msg(buffer);
173	ev = (struct proc_event *)msg->data;
174	memset(&ev->event_data, 0, sizeof(ev->event_data));
175	get_seq(&msg->seq, &ev->cpu);
176	ev->timestamp_ns = ktime_get_ns();
177	ev->what = PROC_EVENT_SID;
178	ev->event_data.sid.process_pid = task->pid;
179	ev->event_data.sid.process_tgid = task->tgid;
180
181	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
182	msg->ack = 0; /* not used */
183	msg->len = sizeof(*ev);
184	msg->flags = 0; /* not used */
185	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
186}
187
188void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
189{
190	struct cn_msg *msg;
191	struct proc_event *ev;
192	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
193
194	if (atomic_read(&proc_event_num_listeners) < 1)
195		return;
196
197	msg = buffer_to_cn_msg(buffer);
198	ev = (struct proc_event *)msg->data;
199	memset(&ev->event_data, 0, sizeof(ev->event_data));
200	get_seq(&msg->seq, &ev->cpu);
201	ev->timestamp_ns = ktime_get_ns();
202	ev->what = PROC_EVENT_PTRACE;
203	ev->event_data.ptrace.process_pid  = task->pid;
204	ev->event_data.ptrace.process_tgid = task->tgid;
205	if (ptrace_id == PTRACE_ATTACH) {
206		ev->event_data.ptrace.tracer_pid  = current->pid;
207		ev->event_data.ptrace.tracer_tgid = current->tgid;
208	} else if (ptrace_id == PTRACE_DETACH) {
209		ev->event_data.ptrace.tracer_pid  = 0;
210		ev->event_data.ptrace.tracer_tgid = 0;
211	} else
212		return;
213
214	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
215	msg->ack = 0; /* not used */
216	msg->len = sizeof(*ev);
217	msg->flags = 0; /* not used */
218	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
219}
220
221void proc_comm_connector(struct task_struct *task)
222{
223	struct cn_msg *msg;
224	struct proc_event *ev;
225	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
226
227	if (atomic_read(&proc_event_num_listeners) < 1)
228		return;
229
230	msg = buffer_to_cn_msg(buffer);
231	ev = (struct proc_event *)msg->data;
232	memset(&ev->event_data, 0, sizeof(ev->event_data));
233	get_seq(&msg->seq, &ev->cpu);
234	ev->timestamp_ns = ktime_get_ns();
235	ev->what = PROC_EVENT_COMM;
236	ev->event_data.comm.process_pid  = task->pid;
237	ev->event_data.comm.process_tgid = task->tgid;
238	get_task_comm(ev->event_data.comm.comm, task);
239
240	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
241	msg->ack = 0; /* not used */
242	msg->len = sizeof(*ev);
243	msg->flags = 0; /* not used */
244	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
245}
246
247void proc_coredump_connector(struct task_struct *task)
248{
249	struct cn_msg *msg;
250	struct proc_event *ev;
 
251	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
252
253	if (atomic_read(&proc_event_num_listeners) < 1)
254		return;
255
256	msg = buffer_to_cn_msg(buffer);
257	ev = (struct proc_event *)msg->data;
258	memset(&ev->event_data, 0, sizeof(ev->event_data));
259	get_seq(&msg->seq, &ev->cpu);
260	ev->timestamp_ns = ktime_get_ns();
261	ev->what = PROC_EVENT_COREDUMP;
262	ev->event_data.coredump.process_pid = task->pid;
263	ev->event_data.coredump.process_tgid = task->tgid;
264
 
 
 
 
 
 
 
 
265	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
266	msg->ack = 0; /* not used */
267	msg->len = sizeof(*ev);
268	msg->flags = 0; /* not used */
269	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
270}
271
272void proc_exit_connector(struct task_struct *task)
273{
274	struct cn_msg *msg;
275	struct proc_event *ev;
 
276	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
277
278	if (atomic_read(&proc_event_num_listeners) < 1)
279		return;
280
281	msg = buffer_to_cn_msg(buffer);
282	ev = (struct proc_event *)msg->data;
283	memset(&ev->event_data, 0, sizeof(ev->event_data));
284	get_seq(&msg->seq, &ev->cpu);
285	ev->timestamp_ns = ktime_get_ns();
286	ev->what = PROC_EVENT_EXIT;
287	ev->event_data.exit.process_pid = task->pid;
288	ev->event_data.exit.process_tgid = task->tgid;
289	ev->event_data.exit.exit_code = task->exit_code;
290	ev->event_data.exit.exit_signal = task->exit_signal;
291
 
 
 
 
 
 
 
 
292	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
293	msg->ack = 0; /* not used */
294	msg->len = sizeof(*ev);
295	msg->flags = 0; /* not used */
296	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
297}
298
299/*
300 * Send an acknowledgement message to userspace
301 *
302 * Use 0 for success, EFOO otherwise.
303 * Note: this is the negative of conventional kernel error
304 * values because it's not being returned via syscall return
305 * mechanisms.
306 */
307static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
308{
309	struct cn_msg *msg;
310	struct proc_event *ev;
311	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
312
313	if (atomic_read(&proc_event_num_listeners) < 1)
314		return;
315
316	msg = buffer_to_cn_msg(buffer);
317	ev = (struct proc_event *)msg->data;
318	memset(&ev->event_data, 0, sizeof(ev->event_data));
319	msg->seq = rcvd_seq;
320	ev->timestamp_ns = ktime_get_ns();
321	ev->cpu = -1;
322	ev->what = PROC_EVENT_NONE;
323	ev->event_data.ack.err = err;
324	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
325	msg->ack = rcvd_ack + 1;
326	msg->len = sizeof(*ev);
327	msg->flags = 0; /* not used */
328	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
329}
330
331/**
332 * cn_proc_mcast_ctl
333 * @data: message sent from userspace via the connector
 
334 */
335static void cn_proc_mcast_ctl(struct cn_msg *msg,
336			      struct netlink_skb_parms *nsp)
337{
338	enum proc_cn_mcast_op *mc_op = NULL;
339	int err = 0;
340
341	if (msg->len != sizeof(*mc_op))
342		return;
343
344	/* 
345	 * Events are reported with respect to the initial pid
346	 * and user namespaces so ignore requestors from
347	 * other namespaces.
348	 */
349	if ((current_user_ns() != &init_user_ns) ||
350	    (task_active_pid_ns(current) != &init_pid_ns))
351		return;
352
353	/* Can only change if privileged. */
354	if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
355		err = EPERM;
356		goto out;
 
 
 
 
 
357	}
358
359	mc_op = (enum proc_cn_mcast_op *)msg->data;
360	switch (*mc_op) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
361	case PROC_CN_MCAST_LISTEN:
362		atomic_inc(&proc_event_num_listeners);
 
363		break;
364	case PROC_CN_MCAST_IGNORE:
365		atomic_dec(&proc_event_num_listeners);
 
 
 
366		break;
367	default:
368		err = EINVAL;
369		break;
370	}
371
372out:
373	cn_proc_ack(err, msg->seq, msg->ack);
374}
375
376/*
377 * cn_proc_init - initialization entry point
378 *
379 * Adds the connector callback to the connector driver.
380 */
381static int __init cn_proc_init(void)
382{
383	int err = cn_add_callback(&cn_proc_event_id,
384				  "cn_proc",
385				  &cn_proc_mcast_ctl);
386	if (err) {
387		pr_warn("cn_proc failed to register\n");
388		return err;
389	}
390	return 0;
391}
392
393module_init(cn_proc_init);