[deliverable/linux.git] / drivers / connector / cn_proc.c

/*
 * cn_proc.c - process events connector
 *
 * Copyright (C) Matt Helsley, IBM Corp. 2005
 * Based on cn_fork.c by Guillaume Thouvenin <guillaume.thouvenin@bull.net>
 * Original copyright notice follows:
 * Copyright (C) 2005 BULL SA.
 *
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/kernel.h>
#include <linux/ktime.h>
#include <linux/init.h>
#include <linux/connector.h>
#include <linux/gfp.h>
#include <linux/ptrace.h>
#include <linux/atomic.h>
#include <linux/pid_namespace.h>

#include <linux/cn_proc.h>

/*
 * Size of a cn_msg followed by a proc_event structure.  Since the
 * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
 * add one 4-byte word to the size here, and then start the actual
 * cn_msg structure 4 bytes into the stack buffer.  The result is that
 * the immediately following proc_event structure is aligned to 8 bytes.
 */
#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)

/* See comment above; we test our assumption about sizeof struct cn_msg here. */
static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)
{
	BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
	return (struct cn_msg *)(buffer + 4);
}

static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };

/* proc_event_counts is used as the sequence number of the netlink message */
static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };

static inline void send_msg(struct cn_msg *msg)
{
	preempt_disable();

	msg->seq = __this_cpu_inc_return(proc_event_counts) - 1;
	((struct proc_event *)msg->data)->cpu = smp_processor_id();

	/*
	 * Preemption remains disabled during send to ensure the messages are
	 * ordered according to their sequence numbers.
	 *
	 * If cn_netlink_send() fails, the data is not sent.
	 */
	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT);

	preempt_enable();
}

void proc_fork_connector(struct task_struct *task)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
	struct task_struct *parent;

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->timestamp_ns = ktime_get_ns();
	ev->what = PROC_EVENT_FORK;
	rcu_read_lock();
	parent = rcu_dereference(task->real_parent);
	ev->event_data.fork.parent_pid = parent->pid;
	ev->event_data.fork.parent_tgid = parent->tgid;
	rcu_read_unlock();
	ev->event_data.fork.child_pid = task->pid;
	ev->event_data.fork.child_tgid = task->tgid;

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

void proc_exec_connector(struct task_struct *task)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->timestamp_ns = ktime_get_ns();
	ev->what = PROC_EVENT_EXEC;
	ev->event_data.exec.process_pid = task->pid;
	ev->event_data.exec.process_tgid = task->tgid;

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

void proc_id_connector(struct task_struct *task, int which_id)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
	const struct cred *cred;

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->what = which_id;
	ev->event_data.id.process_pid = task->pid;
	ev->event_data.id.process_tgid = task->tgid;
	rcu_read_lock();
	cred = __task_cred(task);
	if (which_id == PROC_EVENT_UID) {
		ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
		ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
	} else if (which_id == PROC_EVENT_GID) {
		ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
		ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
	} else {
		rcu_read_unlock();
		return;
	}
	rcu_read_unlock();
	ev->timestamp_ns = ktime_get_ns();

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

void proc_sid_connector(struct task_struct *task)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->timestamp_ns = ktime_get_ns();
	ev->what = PROC_EVENT_SID;
	ev->event_data.sid.process_pid = task->pid;
	ev->event_data.sid.process_tgid = task->tgid;

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->timestamp_ns = ktime_get_ns();
	ev->what = PROC_EVENT_PTRACE;
	ev->event_data.ptrace.process_pid  = task->pid;
	ev->event_data.ptrace.process_tgid = task->tgid;
	if (ptrace_id == PTRACE_ATTACH) {
		ev->event_data.ptrace.tracer_pid  = current->pid;
		ev->event_data.ptrace.tracer_tgid = current->tgid;
	} else if (ptrace_id == PTRACE_DETACH) {
		ev->event_data.ptrace.tracer_pid  = 0;
		ev->event_data.ptrace.tracer_tgid = 0;
	} else
		return;

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

void proc_comm_connector(struct task_struct *task)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->timestamp_ns = ktime_get_ns();
	ev->what = PROC_EVENT_COMM;
	ev->event_data.comm.process_pid  = task->pid;
	ev->event_data.comm.process_tgid = task->tgid;
	get_task_comm(ev->event_data.comm.comm, task);

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

void proc_coredump_connector(struct task_struct *task)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->timestamp_ns = ktime_get_ns();
	ev->what = PROC_EVENT_COREDUMP;
	ev->event_data.coredump.process_pid = task->pid;
	ev->event_data.coredump.process_tgid = task->tgid;

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

void proc_exit_connector(struct task_struct *task)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	ev->timestamp_ns = ktime_get_ns();
	ev->what = PROC_EVENT_EXIT;
	ev->event_data.exit.process_pid = task->pid;
	ev->event_data.exit.process_tgid = task->tgid;
	ev->event_data.exit.exit_code = task->exit_code;
	ev->event_data.exit.exit_signal = task->exit_signal;

	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = 0; /* not used */
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

/*
 * Send an acknowledgement message to userspace
 *
 * Use 0 for success, EFOO otherwise.
 * Note: this is the negative of conventional kernel error
 * values because it's not being returned via syscall return
 * mechanisms.
 */
static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
{
	struct cn_msg *msg;
	struct proc_event *ev;
	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);

	if (atomic_read(&proc_event_num_listeners) < 1)
		return;

	msg = buffer_to_cn_msg(buffer);
	ev = (struct proc_event *)msg->data;
	memset(&ev->event_data, 0, sizeof(ev->event_data));
	msg->seq = rcvd_seq;
	ev->timestamp_ns = ktime_get_ns();
	ev->cpu = -1;
	ev->what = PROC_EVENT_NONE;
	ev->event_data.ack.err = err;
	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	msg->ack = rcvd_ack + 1;
	msg->len = sizeof(*ev);
	msg->flags = 0; /* not used */
	send_msg(msg);
}

/**
 * cn_proc_mcast_ctl
 * @data: message sent from userspace via the connector
 */
static void cn_proc_mcast_ctl(struct cn_msg *msg,
			      struct netlink_skb_parms *nsp)
{
	enum proc_cn_mcast_op *mc_op = NULL;
	int err = 0;

	if (msg->len != sizeof(*mc_op))
		return;

	/* 
	 * Events are reported with respect to the initial pid
	 * and user namespaces so ignore requestors from
	 * other namespaces.
	 */
	if ((current_user_ns() != &init_user_ns) ||
	    (task_active_pid_ns(current) != &init_pid_ns))
		return;

	/* Can only change if privileged. */
	if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
		err = EPERM;
		goto out;
	}

	mc_op = (enum proc_cn_mcast_op *)msg->data;
	switch (*mc_op) {
	case PROC_CN_MCAST_LISTEN:
		atomic_inc(&proc_event_num_listeners);
		break;
	case PROC_CN_MCAST_IGNORE:
		atomic_dec(&proc_event_num_listeners);
		break;
	default:
		err = EINVAL;
		break;
	}

out:
	cn_proc_ack(err, msg->seq, msg->ack);
}

/*
 * cn_proc_init - initialization entry point
 *
 * Adds the connector callback to the connector driver.
 */
static int __init cn_proc_init(void)
{
	int err = cn_add_callback(&cn_proc_event_id,
				  "cn_proc",
				  &cn_proc_mcast_ctl);
	if (err) {
		pr_warn("cn_proc failed to register\n");
		return err;
	}
	return 0;
}
device_initcall(cn_proc_init);
Commit	Line	Data
9f46080c MH	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
9f46080c	25	#include <linux/kernel.h>
caf3c9dc	26	#include <linux/ktime.h>
9f46080c	27	#include <linux/init.h>
1d31a4ea	28	#include <linux/connector.h>
5a0e3ad6	29	#include <linux/gfp.h>
f701e5b7	30	#include <linux/ptrace.h>
60063497	31	#include <linux/atomic.h>
9582d901	32	#include <linux/pid_namespace.h>
60063497	33
9f46080c MH	34	#include <linux/cn_proc.h>
9f46080c MH	35
1ca1a4cf CM	36	/*
	37	* Size of a cn_msg followed by a proc_event structure. Since the
	38	* sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
	39	* add one 4-byte word to the size here, and then start the actual
	40	* cn_msg structure 4 bytes into the stack buffer. The result is that
	41	* the immediately following proc_event structure is aligned to 8 bytes.
	42	*/
	43	#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)
	44
	45	/* See comment above; we test our assumption about sizeof struct cn_msg here. */
	46	static inline struct cn_msg buffer_to_cn_msg(__u8 buffer)
	47	{
	48	BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
	49	return (struct cn_msg *)(buffer + 4);
	50	}
9f46080c MH	51
	52	static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
	53	static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
	54
cc398c2e	55	/* proc_event_counts is used as the sequence number of the netlink message */
9f46080c MH	56	static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
9f46080c MH	57
ab8ed951	58	static inline void send_msg(struct cn_msg *msg)
9f46080c	59	{
3ea9f683	60	preempt_disable();
ab8ed951 AC	61
	62	msg->seq = __this_cpu_inc_return(proc_event_counts) - 1;
	63	((struct proc_event *)msg->data)->cpu = smp_processor_id();
	64
	65	/*
	66	* Preemption remains disabled during send to ensure the messages are
	67	* ordered according to their sequence numbers.
	68	*
	69	* If cn_netlink_send() fails, the data is not sent.
	70	*/
	71	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT);
	72
3ea9f683	73	preempt_enable();
9f46080c MH	74	}
	75
	76	void proc_fork_connector(struct task_struct *task)
	77	{
	78	struct cn_msg *msg;
	79	struct proc_event *ev;
1ca1a4cf	80	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9e8f90df	81	struct task_struct *parent;
9f46080c MH	82
	83	if (atomic_read(&proc_event_num_listeners) < 1)
	84	return;
	85
1ca1a4cf	86	msg = buffer_to_cn_msg(buffer);
f3c48ecc	87	ev = (struct proc_event *)msg->data;
e727ca82	88	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	89	ev->timestamp_ns = ktime_get_ns();
9f46080c	90	ev->what = PROC_EVENT_FORK;
9e8f90df ON	91	rcu_read_lock();
	92	parent = rcu_dereference(task->real_parent);
	93	ev->event_data.fork.parent_pid = parent->pid;
	94	ev->event_data.fork.parent_tgid = parent->tgid;
	95	rcu_read_unlock();
9f46080c MH	96	ev->event_data.fork.child_pid = task->pid;
	97	ev->event_data.fork.child_tgid = task->tgid;
	98
	99	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	100	msg->ack = 0; /* not used */
	101	msg->len = sizeof(*ev);
e727ca82	102	msg->flags = 0; /* not used */
ab8ed951	103	send_msg(msg);
9f46080c MH	104	}
	105
	106	void proc_exec_connector(struct task_struct *task)
	107	{
	108	struct cn_msg *msg;
	109	struct proc_event *ev;
1ca1a4cf	110	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9f46080c MH	111
	112	if (atomic_read(&proc_event_num_listeners) < 1)
	113	return;
	114
1ca1a4cf	115	msg = buffer_to_cn_msg(buffer);
f3c48ecc	116	ev = (struct proc_event *)msg->data;
e727ca82	117	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	118	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	119	ev->what = PROC_EVENT_EXEC;
	120	ev->event_data.exec.process_pid = task->pid;
	121	ev->event_data.exec.process_tgid = task->tgid;
	122
	123	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	124	msg->ack = 0; /* not used */
	125	msg->len = sizeof(*ev);
e727ca82	126	msg->flags = 0; /* not used */
ab8ed951	127	send_msg(msg);
9f46080c MH	128	}
	129
	130	void proc_id_connector(struct task_struct *task, int which_id)
	131	{
	132	struct cn_msg *msg;
	133	struct proc_event *ev;
1ca1a4cf	134	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
c69e8d9c	135	const struct cred *cred;
9f46080c MH	136
	137	if (atomic_read(&proc_event_num_listeners) < 1)
	138	return;
	139
1ca1a4cf	140	msg = buffer_to_cn_msg(buffer);
f3c48ecc	141	ev = (struct proc_event *)msg->data;
e727ca82	142	memset(&ev->event_data, 0, sizeof(ev->event_data));
9f46080c MH	143	ev->what = which_id;
	144	ev->event_data.id.process_pid = task->pid;
	145	ev->event_data.id.process_tgid = task->tgid;
c69e8d9c DH	146	rcu_read_lock();
c69e8d9c DH	147	cred = __task_cred(task);
9f46080c	148	if (which_id == PROC_EVENT_UID) {
9582d901 EB	149	ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
9582d901 EB	150	ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
9f46080c	151	} else if (which_id == PROC_EVENT_GID) {
9582d901 EB	152	ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
9582d901 EB	153	ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
c69e8d9c DH	154	} else {
c69e8d9c DH	155	rcu_read_unlock();
f3c48ecc	156	return;
c69e8d9c DH	157	}
c69e8d9c DH	158	rcu_read_unlock();
9e93f21b	159	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	160
	161	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	162	msg->ack = 0; /* not used */
	163	msg->len = sizeof(*ev);
e727ca82	164	msg->flags = 0; /* not used */
ab8ed951	165	send_msg(msg);
9f46080c MH	166	}
9f46080c MH	167
02b51df1 SJR	168	void proc_sid_connector(struct task_struct *task)
	169	{
	170	struct cn_msg *msg;
	171	struct proc_event *ev;
1ca1a4cf	172	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
02b51df1 SJR	173
	174	if (atomic_read(&proc_event_num_listeners) < 1)
	175	return;
	176
1ca1a4cf	177	msg = buffer_to_cn_msg(buffer);
02b51df1	178	ev = (struct proc_event *)msg->data;
e727ca82	179	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	180	ev->timestamp_ns = ktime_get_ns();
02b51df1 SJR	181	ev->what = PROC_EVENT_SID;
	182	ev->event_data.sid.process_pid = task->pid;
	183	ev->event_data.sid.process_tgid = task->tgid;
	184
	185	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	186	msg->ack = 0; /* not used */
	187	msg->len = sizeof(*ev);
e727ca82	188	msg->flags = 0; /* not used */
ab8ed951	189	send_msg(msg);
02b51df1 SJR	190	}
02b51df1 SJR	191
f701e5b7 VZ	192	void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
	193	{
	194	struct cn_msg *msg;
	195	struct proc_event *ev;
1ca1a4cf	196	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
f701e5b7 VZ	197
	198	if (atomic_read(&proc_event_num_listeners) < 1)
	199	return;
	200
1ca1a4cf	201	msg = buffer_to_cn_msg(buffer);
f701e5b7	202	ev = (struct proc_event *)msg->data;
e727ca82	203	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	204	ev->timestamp_ns = ktime_get_ns();
f701e5b7 VZ	205	ev->what = PROC_EVENT_PTRACE;
	206	ev->event_data.ptrace.process_pid = task->pid;
	207	ev->event_data.ptrace.process_tgid = task->tgid;
	208	if (ptrace_id == PTRACE_ATTACH) {
	209	ev->event_data.ptrace.tracer_pid = current->pid;
	210	ev->event_data.ptrace.tracer_tgid = current->tgid;
	211	} else if (ptrace_id == PTRACE_DETACH) {
	212	ev->event_data.ptrace.tracer_pid = 0;
	213	ev->event_data.ptrace.tracer_tgid = 0;
	214	} else
	215	return;
	216
	217	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	218	msg->ack = 0; /* not used */
	219	msg->len = sizeof(*ev);
e727ca82	220	msg->flags = 0; /* not used */
ab8ed951	221	send_msg(msg);
f701e5b7 VZ	222	}
f701e5b7 VZ	223
f786ecba VZ	224	void proc_comm_connector(struct task_struct *task)
	225	{
	226	struct cn_msg *msg;
	227	struct proc_event *ev;
1ca1a4cf	228	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
f786ecba VZ	229
	230	if (atomic_read(&proc_event_num_listeners) < 1)
	231	return;
	232
1ca1a4cf	233	msg = buffer_to_cn_msg(buffer);
f786ecba	234	ev = (struct proc_event *)msg->data;
e727ca82	235	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	236	ev->timestamp_ns = ktime_get_ns();
f786ecba VZ	237	ev->what = PROC_EVENT_COMM;
	238	ev->event_data.comm.process_pid = task->pid;
	239	ev->event_data.comm.process_tgid = task->tgid;
	240	get_task_comm(ev->event_data.comm.comm, task);
	241
	242	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	243	msg->ack = 0; /* not used */
	244	msg->len = sizeof(*ev);
e727ca82	245	msg->flags = 0; /* not used */
ab8ed951	246	send_msg(msg);
2b5faa4c JD	247	}
	248
	249	void proc_coredump_connector(struct task_struct *task)
	250	{
	251	struct cn_msg *msg;
	252	struct proc_event *ev;
1ca1a4cf	253	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
2b5faa4c JD	254
	255	if (atomic_read(&proc_event_num_listeners) < 1)
	256	return;
	257
1ca1a4cf	258	msg = buffer_to_cn_msg(buffer);
2b5faa4c	259	ev = (struct proc_event *)msg->data;
e727ca82	260	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	261	ev->timestamp_ns = ktime_get_ns();
2b5faa4c JD	262	ev->what = PROC_EVENT_COREDUMP;
	263	ev->event_data.coredump.process_pid = task->pid;
	264	ev->event_data.coredump.process_tgid = task->tgid;
	265
	266	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	267	msg->ack = 0; /* not used */
	268	msg->len = sizeof(*ev);
e727ca82	269	msg->flags = 0; /* not used */
ab8ed951	270	send_msg(msg);
f786ecba VZ	271	}
f786ecba VZ	272
9f46080c MH	273	void proc_exit_connector(struct task_struct *task)
	274	{
	275	struct cn_msg *msg;
	276	struct proc_event *ev;
1ca1a4cf	277	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9f46080c MH	278
	279	if (atomic_read(&proc_event_num_listeners) < 1)
	280	return;
	281
1ca1a4cf	282	msg = buffer_to_cn_msg(buffer);
f3c48ecc	283	ev = (struct proc_event *)msg->data;
e727ca82	284	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	285	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	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);
e727ca82	295	msg->flags = 0; /* not used */
ab8ed951	296	send_msg(msg);
9f46080c MH	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	*/
	307	static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
	308	{
	309	struct cn_msg *msg;
	310	struct proc_event *ev;
1ca1a4cf	311	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9f46080c MH	312
	313	if (atomic_read(&proc_event_num_listeners) < 1)
	314	return;
	315
1ca1a4cf	316	msg = buffer_to_cn_msg(buffer);
f3c48ecc	317	ev = (struct proc_event *)msg->data;
e727ca82	318	memset(&ev->event_data, 0, sizeof(ev->event_data));
9f46080c	319	msg->seq = rcvd_seq;
9e93f21b	320	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	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);
e727ca82	327	msg->flags = 0; /* not used */
ab8ed951	328	send_msg(msg);
9f46080c MH	329	}
	330
	331	/**
	332	* cn_proc_mcast_ctl
	333	* @data: message sent from userspace via the connector
	334	*/
f0b25932 SB	335	static void cn_proc_mcast_ctl(struct cn_msg *msg,
f0b25932 SB	336	struct netlink_skb_parms *nsp)
9f46080c	337	{
9f46080c MH	338	enum proc_cn_mcast_op *mc_op = NULL;
	339	int err = 0;
	340
	341	if (msg->len != sizeof(*mc_op))
	342	return;
	343
9582d901 EB	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
e70ab977	353	/* Can only change if privileged. */
90f62cf3	354	if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
e70ab977 KC	355	err = EPERM;
	356	goto out;
	357	}
	358
f3c48ecc	359	mc_op = (enum proc_cn_mcast_op *)msg->data;
9f46080c MH	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	}
e70ab977 KC	371
e70ab977 KC	372	out:
9f46080c MH	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	*/
	381	static int __init cn_proc_init(void)
	382	{
f3c48ecc VI	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");
9f46080c MH	388	return err;
	389	}
	390	return 0;
	391	}
8297f2d9	392	device_initcall(cn_proc_init);