[linux-block.git] / drivers / connector / cn_proc.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * 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.
 */

#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>
#include <linux/local_lock.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 };

/* local_event.count is used as the sequence number of the netlink message */
struct local_event {
	local_lock_t lock;
	__u32 count;
};
static DEFINE_PER_CPU(struct local_event, local_event) = {
	.lock = INIT_LOCAL_LOCK(lock),
};

static inline void send_msg(struct cn_msg *msg)
{
	local_lock(&local_event.lock);

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

	/*
	 * local_lock() disables preemption 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);

	local_unlock(&local_event.lock);
}

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;
	struct task_struct *parent;
	__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;

	rcu_read_lock();
	if (pid_alive(task)) {
		parent = rcu_dereference(task->real_parent);
		ev->event_data.coredump.parent_pid = parent->pid;
		ev->event_data.coredump.parent_tgid = parent->tgid;
	}
	rcu_read_unlock();

	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;
	struct task_struct *parent;
	__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;

	rcu_read_lock();
	if (pid_alive(task)) {
		parent = rcu_dereference(task->real_parent);
		ev->event_data.exit.parent_pid = parent->pid;
		ev->event_data.exit.parent_tgid = parent->tgid;
	}
	rcu_read_unlock();

	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
1a59d1b8	1	// SPDX-License-Identifier: GPL-2.0-or-later
9f46080c MH	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.
9f46080c MH	9	*/
9f46080c MH	10
9f46080c	11	#include <linux/kernel.h>
caf3c9dc	12	#include <linux/ktime.h>
9f46080c	13	#include <linux/init.h>
1d31a4ea	14	#include <linux/connector.h>
5a0e3ad6	15	#include <linux/gfp.h>
f701e5b7	16	#include <linux/ptrace.h>
60063497	17	#include <linux/atomic.h>
9582d901	18	#include <linux/pid_namespace.h>
60063497	19
9f46080c	20	#include <linux/cn_proc.h>
3e92fd7b	21	#include <linux/local_lock.h>
9f46080c	22
1ca1a4cf CM	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. */
	33	static 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	}
9f46080c MH	38
	39	static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
	40	static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
	41
3e92fd7b MG	42	/* local_event.count is used as the sequence number of the netlink message */
	43	struct local_event {
	44	local_lock_t lock;
	45	__u32 count;
	46	};
	47	static DEFINE_PER_CPU(struct local_event, local_event) = {
	48	.lock = INIT_LOCAL_LOCK(lock),
	49	};
9f46080c	50
ab8ed951	51	static inline void send_msg(struct cn_msg *msg)
9f46080c	52	{
3e92fd7b	53	local_lock(&local_event.lock);
ab8ed951	54
3e92fd7b	55	msg->seq = __this_cpu_inc_return(local_event.count) - 1;
ab8ed951 AC	56	((struct proc_event *)msg->data)->cpu = smp_processor_id();
	57
	58	/*
3e92fd7b MG	59	* local_lock() disables preemption during send to ensure the messages
3e92fd7b MG	60	* are ordered according to their sequence numbers.
ab8ed951 AC	61	*
	62	* If cn_netlink_send() fails, the data is not sent.
	63	*/
	64	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT);
	65
3e92fd7b	66	local_unlock(&local_event.lock);
9f46080c MH	67	}
	68
	69	void proc_fork_connector(struct task_struct *task)
	70	{
	71	struct cn_msg *msg;
	72	struct proc_event *ev;
1ca1a4cf	73	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9e8f90df	74	struct task_struct *parent;
9f46080c MH	75
	76	if (atomic_read(&proc_event_num_listeners) < 1)
	77	return;
	78
1ca1a4cf	79	msg = buffer_to_cn_msg(buffer);
f3c48ecc	80	ev = (struct proc_event *)msg->data;
e727ca82	81	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	82	ev->timestamp_ns = ktime_get_ns();
9f46080c	83	ev->what = PROC_EVENT_FORK;
9e8f90df ON	84	rcu_read_lock();
	85	parent = rcu_dereference(task->real_parent);
	86	ev->event_data.fork.parent_pid = parent->pid;
	87	ev->event_data.fork.parent_tgid = parent->tgid;
	88	rcu_read_unlock();
9f46080c MH	89	ev->event_data.fork.child_pid = task->pid;
	90	ev->event_data.fork.child_tgid = task->tgid;
	91
	92	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	93	msg->ack = 0; /* not used */
	94	msg->len = sizeof(*ev);
e727ca82	95	msg->flags = 0; /* not used */
ab8ed951	96	send_msg(msg);
9f46080c MH	97	}
	98
	99	void proc_exec_connector(struct task_struct *task)
	100	{
	101	struct cn_msg *msg;
	102	struct proc_event *ev;
1ca1a4cf	103	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9f46080c MH	104
	105	if (atomic_read(&proc_event_num_listeners) < 1)
	106	return;
	107
1ca1a4cf	108	msg = buffer_to_cn_msg(buffer);
f3c48ecc	109	ev = (struct proc_event *)msg->data;
e727ca82	110	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	111	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	112	ev->what = PROC_EVENT_EXEC;
	113	ev->event_data.exec.process_pid = task->pid;
	114	ev->event_data.exec.process_tgid = task->tgid;
	115
	116	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	117	msg->ack = 0; /* not used */
	118	msg->len = sizeof(*ev);
e727ca82	119	msg->flags = 0; /* not used */
ab8ed951	120	send_msg(msg);
9f46080c MH	121	}
	122
	123	void proc_id_connector(struct task_struct *task, int which_id)
	124	{
	125	struct cn_msg *msg;
	126	struct proc_event *ev;
1ca1a4cf	127	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
c69e8d9c	128	const struct cred *cred;
9f46080c MH	129
	130	if (atomic_read(&proc_event_num_listeners) < 1)
	131	return;
	132
1ca1a4cf	133	msg = buffer_to_cn_msg(buffer);
f3c48ecc	134	ev = (struct proc_event *)msg->data;
e727ca82	135	memset(&ev->event_data, 0, sizeof(ev->event_data));
9f46080c MH	136	ev->what = which_id;
	137	ev->event_data.id.process_pid = task->pid;
	138	ev->event_data.id.process_tgid = task->tgid;
c69e8d9c DH	139	rcu_read_lock();
c69e8d9c DH	140	cred = __task_cred(task);
9f46080c	141	if (which_id == PROC_EVENT_UID) {
9582d901 EB	142	ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
9582d901 EB	143	ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
9f46080c	144	} else if (which_id == PROC_EVENT_GID) {
9582d901 EB	145	ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
9582d901 EB	146	ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
c69e8d9c DH	147	} else {
c69e8d9c DH	148	rcu_read_unlock();
f3c48ecc	149	return;
c69e8d9c DH	150	}
c69e8d9c DH	151	rcu_read_unlock();
9e93f21b	152	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	153
	154	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	155	msg->ack = 0; /* not used */
	156	msg->len = sizeof(*ev);
e727ca82	157	msg->flags = 0; /* not used */
ab8ed951	158	send_msg(msg);
9f46080c MH	159	}
9f46080c MH	160
02b51df1 SJR	161	void proc_sid_connector(struct task_struct *task)
	162	{
	163	struct cn_msg *msg;
	164	struct proc_event *ev;
1ca1a4cf	165	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
02b51df1 SJR	166
	167	if (atomic_read(&proc_event_num_listeners) < 1)
	168	return;
	169
1ca1a4cf	170	msg = buffer_to_cn_msg(buffer);
02b51df1	171	ev = (struct proc_event *)msg->data;
e727ca82	172	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	173	ev->timestamp_ns = ktime_get_ns();
02b51df1 SJR	174	ev->what = PROC_EVENT_SID;
	175	ev->event_data.sid.process_pid = task->pid;
	176	ev->event_data.sid.process_tgid = task->tgid;
	177
	178	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	179	msg->ack = 0; /* not used */
	180	msg->len = sizeof(*ev);
e727ca82	181	msg->flags = 0; /* not used */
ab8ed951	182	send_msg(msg);
02b51df1 SJR	183	}
02b51df1 SJR	184
f701e5b7 VZ	185	void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
	186	{
	187	struct cn_msg *msg;
	188	struct proc_event *ev;
1ca1a4cf	189	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
f701e5b7 VZ	190
	191	if (atomic_read(&proc_event_num_listeners) < 1)
	192	return;
	193
1ca1a4cf	194	msg = buffer_to_cn_msg(buffer);
f701e5b7	195	ev = (struct proc_event *)msg->data;
e727ca82	196	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	197	ev->timestamp_ns = ktime_get_ns();
f701e5b7 VZ	198	ev->what = PROC_EVENT_PTRACE;
	199	ev->event_data.ptrace.process_pid = task->pid;
	200	ev->event_data.ptrace.process_tgid = task->tgid;
	201	if (ptrace_id == PTRACE_ATTACH) {
	202	ev->event_data.ptrace.tracer_pid = current->pid;
	203	ev->event_data.ptrace.tracer_tgid = current->tgid;
	204	} else if (ptrace_id == PTRACE_DETACH) {
	205	ev->event_data.ptrace.tracer_pid = 0;
	206	ev->event_data.ptrace.tracer_tgid = 0;
	207	} else
	208	return;
	209
	210	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	211	msg->ack = 0; /* not used */
	212	msg->len = sizeof(*ev);
e727ca82	213	msg->flags = 0; /* not used */
ab8ed951	214	send_msg(msg);
f701e5b7 VZ	215	}
f701e5b7 VZ	216
f786ecba VZ	217	void proc_comm_connector(struct task_struct *task)
	218	{
	219	struct cn_msg *msg;
	220	struct proc_event *ev;
1ca1a4cf	221	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
f786ecba VZ	222
	223	if (atomic_read(&proc_event_num_listeners) < 1)
	224	return;
	225
1ca1a4cf	226	msg = buffer_to_cn_msg(buffer);
f786ecba	227	ev = (struct proc_event *)msg->data;
e727ca82	228	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	229	ev->timestamp_ns = ktime_get_ns();
f786ecba VZ	230	ev->what = PROC_EVENT_COMM;
	231	ev->event_data.comm.process_pid = task->pid;
	232	ev->event_data.comm.process_tgid = task->tgid;
	233	get_task_comm(ev->event_data.comm.comm, task);
	234
	235	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	236	msg->ack = 0; /* not used */
	237	msg->len = sizeof(*ev);
e727ca82	238	msg->flags = 0; /* not used */
ab8ed951	239	send_msg(msg);
2b5faa4c JD	240	}
	241
	242	void proc_coredump_connector(struct task_struct *task)
	243	{
	244	struct cn_msg *msg;
	245	struct proc_event *ev;
6d2b0f02	246	struct task_struct *parent;
1ca1a4cf	247	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
2b5faa4c JD	248
	249	if (atomic_read(&proc_event_num_listeners) < 1)
	250	return;
	251
1ca1a4cf	252	msg = buffer_to_cn_msg(buffer);
2b5faa4c	253	ev = (struct proc_event *)msg->data;
e727ca82	254	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	255	ev->timestamp_ns = ktime_get_ns();
2b5faa4c JD	256	ev->what = PROC_EVENT_COREDUMP;
	257	ev->event_data.coredump.process_pid = task->pid;
	258	ev->event_data.coredump.process_tgid = task->tgid;
6d2b0f02 LR	259
	260	rcu_read_lock();
	261	if (pid_alive(task)) {
	262	parent = rcu_dereference(task->real_parent);
	263	ev->event_data.coredump.parent_pid = parent->pid;
	264	ev->event_data.coredump.parent_tgid = parent->tgid;
	265	}
	266	rcu_read_unlock();
2b5faa4c JD	267
	268	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	269	msg->ack = 0; /* not used */
	270	msg->len = sizeof(*ev);
e727ca82	271	msg->flags = 0; /* not used */
ab8ed951	272	send_msg(msg);
f786ecba VZ	273	}
f786ecba VZ	274
9f46080c MH	275	void proc_exit_connector(struct task_struct *task)
	276	{
	277	struct cn_msg *msg;
	278	struct proc_event *ev;
6d2b0f02	279	struct task_struct *parent;
1ca1a4cf	280	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9f46080c MH	281
	282	if (atomic_read(&proc_event_num_listeners) < 1)
	283	return;
	284
1ca1a4cf	285	msg = buffer_to_cn_msg(buffer);
f3c48ecc	286	ev = (struct proc_event *)msg->data;
e727ca82	287	memset(&ev->event_data, 0, sizeof(ev->event_data));
9e93f21b	288	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	289	ev->what = PROC_EVENT_EXIT;
	290	ev->event_data.exit.process_pid = task->pid;
	291	ev->event_data.exit.process_tgid = task->tgid;
	292	ev->event_data.exit.exit_code = task->exit_code;
	293	ev->event_data.exit.exit_signal = task->exit_signal;
6d2b0f02 LR	294
	295	rcu_read_lock();
	296	if (pid_alive(task)) {
	297	parent = rcu_dereference(task->real_parent);
	298	ev->event_data.exit.parent_pid = parent->pid;
	299	ev->event_data.exit.parent_tgid = parent->tgid;
	300	}
	301	rcu_read_unlock();
9f46080c MH	302
	303	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	304	msg->ack = 0; /* not used */
	305	msg->len = sizeof(*ev);
e727ca82	306	msg->flags = 0; /* not used */
ab8ed951	307	send_msg(msg);
9f46080c MH	308	}
	309
	310	/*
	311	* Send an acknowledgement message to userspace
	312	*
	313	* Use 0 for success, EFOO otherwise.
	314	* Note: this is the negative of conventional kernel error
	315	* values because it's not being returned via syscall return
	316	* mechanisms.
	317	*/
	318	static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
	319	{
	320	struct cn_msg *msg;
	321	struct proc_event *ev;
1ca1a4cf	322	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
9f46080c MH	323
	324	if (atomic_read(&proc_event_num_listeners) < 1)
	325	return;
	326
1ca1a4cf	327	msg = buffer_to_cn_msg(buffer);
f3c48ecc	328	ev = (struct proc_event *)msg->data;
e727ca82	329	memset(&ev->event_data, 0, sizeof(ev->event_data));
9f46080c	330	msg->seq = rcvd_seq;
9e93f21b	331	ev->timestamp_ns = ktime_get_ns();
9f46080c MH	332	ev->cpu = -1;
	333	ev->what = PROC_EVENT_NONE;
	334	ev->event_data.ack.err = err;
	335	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
	336	msg->ack = rcvd_ack + 1;
	337	msg->len = sizeof(*ev);
e727ca82	338	msg->flags = 0; /* not used */
ab8ed951	339	send_msg(msg);
9f46080c MH	340	}
	341
	342	/**
	343	* cn_proc_mcast_ctl
	344	* @data: message sent from userspace via the connector
	345	*/
f0b25932 SB	346	static void cn_proc_mcast_ctl(struct cn_msg *msg,
f0b25932 SB	347	struct netlink_skb_parms *nsp)
9f46080c	348	{
9f46080c MH	349	enum proc_cn_mcast_op *mc_op = NULL;
	350	int err = 0;
	351
	352	if (msg->len != sizeof(*mc_op))
	353	return;
	354
9582d901 EB	355	/*
	356	* Events are reported with respect to the initial pid
	357	* and user namespaces so ignore requestors from
	358	* other namespaces.
	359	*/
	360	if ((current_user_ns() != &init_user_ns) \|\|
	361	(task_active_pid_ns(current) != &init_pid_ns))
	362	return;
	363
e70ab977	364	/* Can only change if privileged. */
90f62cf3	365	if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
e70ab977 KC	366	err = EPERM;
	367	goto out;
	368	}
	369
f3c48ecc	370	mc_op = (enum proc_cn_mcast_op *)msg->data;
9f46080c MH	371	switch (*mc_op) {
	372	case PROC_CN_MCAST_LISTEN:
	373	atomic_inc(&proc_event_num_listeners);
	374	break;
	375	case PROC_CN_MCAST_IGNORE:
	376	atomic_dec(&proc_event_num_listeners);
	377	break;
	378	default:
	379	err = EINVAL;
	380	break;
	381	}
e70ab977 KC	382
e70ab977 KC	383	out:
9f46080c MH	384	cn_proc_ack(err, msg->seq, msg->ack);
	385	}
	386
	387	/*
	388	* cn_proc_init - initialization entry point
	389	*
	390	* Adds the connector callback to the connector driver.
	391	*/
	392	static int __init cn_proc_init(void)
	393	{
f3c48ecc VI	394	int err = cn_add_callback(&cn_proc_event_id,
	395	"cn_proc",
	396	&cn_proc_mcast_ctl);
	397	if (err) {
	398	pr_warn("cn_proc failed to register\n");
9f46080c MH	399	return err;
	400	}
	401	return 0;
	402	}
8297f2d9	403	device_initcall(cn_proc_init);