compat: return -EFAULT on error in waitid()
[linux/fpc-iii.git] / drivers / connector / cn_proc.c
blobfce2000eec31d658efb52251b7f6df60822d1798
1 /*
2 * cn_proc.c - process events connector
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.
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.
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.
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
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>
35 #include <asm/unaligned.h>
37 #include <linux/cn_proc.h>
39 #define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event))
41 static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
42 static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
44 /* proc_event_counts is used as the sequence number of the netlink message */
45 static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
47 static inline void get_seq(__u32 *ts, int *cpu)
49 preempt_disable();
50 *ts = __this_cpu_inc_return(proc_event_counts) - 1;
51 *cpu = smp_processor_id();
52 preempt_enable();
55 void proc_fork_connector(struct task_struct *task)
57 struct cn_msg *msg;
58 struct proc_event *ev;
59 __u8 buffer[CN_PROC_MSG_SIZE];
60 struct timespec ts;
61 struct task_struct *parent;
63 if (atomic_read(&proc_event_num_listeners) < 1)
64 return;
66 msg = (struct cn_msg *)buffer;
67 ev = (struct proc_event *)msg->data;
68 get_seq(&msg->seq, &ev->cpu);
69 ktime_get_ts(&ts); /* get high res monotonic timestamp */
70 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
71 ev->what = PROC_EVENT_FORK;
72 rcu_read_lock();
73 parent = rcu_dereference(task->real_parent);
74 ev->event_data.fork.parent_pid = parent->pid;
75 ev->event_data.fork.parent_tgid = parent->tgid;
76 rcu_read_unlock();
77 ev->event_data.fork.child_pid = task->pid;
78 ev->event_data.fork.child_tgid = task->tgid;
80 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
81 msg->ack = 0; /* not used */
82 msg->len = sizeof(*ev);
83 /* If cn_netlink_send() failed, the data is not sent */
84 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
87 void proc_exec_connector(struct task_struct *task)
89 struct cn_msg *msg;
90 struct proc_event *ev;
91 struct timespec ts;
92 __u8 buffer[CN_PROC_MSG_SIZE];
94 if (atomic_read(&proc_event_num_listeners) < 1)
95 return;
97 msg = (struct cn_msg *)buffer;
98 ev = (struct proc_event *)msg->data;
99 get_seq(&msg->seq, &ev->cpu);
100 ktime_get_ts(&ts); /* get high res monotonic timestamp */
101 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
102 ev->what = PROC_EVENT_EXEC;
103 ev->event_data.exec.process_pid = task->pid;
104 ev->event_data.exec.process_tgid = task->tgid;
106 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
107 msg->ack = 0; /* not used */
108 msg->len = sizeof(*ev);
109 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
112 void proc_id_connector(struct task_struct *task, int which_id)
114 struct cn_msg *msg;
115 struct proc_event *ev;
116 __u8 buffer[CN_PROC_MSG_SIZE];
117 struct timespec ts;
118 const struct cred *cred;
120 if (atomic_read(&proc_event_num_listeners) < 1)
121 return;
123 msg = (struct cn_msg *)buffer;
124 ev = (struct proc_event *)msg->data;
125 ev->what = which_id;
126 ev->event_data.id.process_pid = task->pid;
127 ev->event_data.id.process_tgid = task->tgid;
128 rcu_read_lock();
129 cred = __task_cred(task);
130 if (which_id == PROC_EVENT_UID) {
131 ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
132 ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
133 } else if (which_id == PROC_EVENT_GID) {
134 ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
135 ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
136 } else {
137 rcu_read_unlock();
138 return;
140 rcu_read_unlock();
141 get_seq(&msg->seq, &ev->cpu);
142 ktime_get_ts(&ts); /* get high res monotonic timestamp */
143 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
145 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
146 msg->ack = 0; /* not used */
147 msg->len = sizeof(*ev);
148 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
151 void proc_sid_connector(struct task_struct *task)
153 struct cn_msg *msg;
154 struct proc_event *ev;
155 struct timespec ts;
156 __u8 buffer[CN_PROC_MSG_SIZE];
158 if (atomic_read(&proc_event_num_listeners) < 1)
159 return;
161 msg = (struct cn_msg *)buffer;
162 ev = (struct proc_event *)msg->data;
163 get_seq(&msg->seq, &ev->cpu);
164 ktime_get_ts(&ts); /* get high res monotonic timestamp */
165 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
166 ev->what = PROC_EVENT_SID;
167 ev->event_data.sid.process_pid = task->pid;
168 ev->event_data.sid.process_tgid = task->tgid;
170 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
171 msg->ack = 0; /* not used */
172 msg->len = sizeof(*ev);
173 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
176 void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
178 struct cn_msg *msg;
179 struct proc_event *ev;
180 struct timespec ts;
181 __u8 buffer[CN_PROC_MSG_SIZE];
183 if (atomic_read(&proc_event_num_listeners) < 1)
184 return;
186 msg = (struct cn_msg *)buffer;
187 ev = (struct proc_event *)msg->data;
188 get_seq(&msg->seq, &ev->cpu);
189 ktime_get_ts(&ts); /* get high res monotonic timestamp */
190 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_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;
203 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
204 msg->ack = 0; /* not used */
205 msg->len = sizeof(*ev);
206 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
209 void proc_comm_connector(struct task_struct *task)
211 struct cn_msg *msg;
212 struct proc_event *ev;
213 struct timespec ts;
214 __u8 buffer[CN_PROC_MSG_SIZE];
216 if (atomic_read(&proc_event_num_listeners) < 1)
217 return;
219 msg = (struct cn_msg *)buffer;
220 ev = (struct proc_event *)msg->data;
221 get_seq(&msg->seq, &ev->cpu);
222 ktime_get_ts(&ts); /* get high res monotonic timestamp */
223 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
224 ev->what = PROC_EVENT_COMM;
225 ev->event_data.comm.process_pid = task->pid;
226 ev->event_data.comm.process_tgid = task->tgid;
227 get_task_comm(ev->event_data.comm.comm, task);
229 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
230 msg->ack = 0; /* not used */
231 msg->len = sizeof(*ev);
232 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
235 void proc_exit_connector(struct task_struct *task)
237 struct cn_msg *msg;
238 struct proc_event *ev;
239 __u8 buffer[CN_PROC_MSG_SIZE];
240 struct timespec ts;
242 if (atomic_read(&proc_event_num_listeners) < 1)
243 return;
245 msg = (struct cn_msg *)buffer;
246 ev = (struct proc_event *)msg->data;
247 get_seq(&msg->seq, &ev->cpu);
248 ktime_get_ts(&ts); /* get high res monotonic timestamp */
249 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
250 ev->what = PROC_EVENT_EXIT;
251 ev->event_data.exit.process_pid = task->pid;
252 ev->event_data.exit.process_tgid = task->tgid;
253 ev->event_data.exit.exit_code = task->exit_code;
254 ev->event_data.exit.exit_signal = task->exit_signal;
256 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
257 msg->ack = 0; /* not used */
258 msg->len = sizeof(*ev);
259 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
263 * Send an acknowledgement message to userspace
265 * Use 0 for success, EFOO otherwise.
266 * Note: this is the negative of conventional kernel error
267 * values because it's not being returned via syscall return
268 * mechanisms.
270 static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
272 struct cn_msg *msg;
273 struct proc_event *ev;
274 __u8 buffer[CN_PROC_MSG_SIZE];
275 struct timespec ts;
277 if (atomic_read(&proc_event_num_listeners) < 1)
278 return;
280 msg = (struct cn_msg *)buffer;
281 ev = (struct proc_event *)msg->data;
282 msg->seq = rcvd_seq;
283 ktime_get_ts(&ts); /* get high res monotonic timestamp */
284 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
285 ev->cpu = -1;
286 ev->what = PROC_EVENT_NONE;
287 ev->event_data.ack.err = err;
288 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
289 msg->ack = rcvd_ack + 1;
290 msg->len = sizeof(*ev);
291 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
295 * cn_proc_mcast_ctl
296 * @data: message sent from userspace via the connector
298 static void cn_proc_mcast_ctl(struct cn_msg *msg,
299 struct netlink_skb_parms *nsp)
301 enum proc_cn_mcast_op *mc_op = NULL;
302 int err = 0;
304 if (msg->len != sizeof(*mc_op))
305 return;
308 * Events are reported with respect to the initial pid
309 * and user namespaces so ignore requestors from
310 * other namespaces.
312 if ((current_user_ns() != &init_user_ns) ||
313 (task_active_pid_ns(current) != &init_pid_ns))
314 return;
316 mc_op = (enum proc_cn_mcast_op *)msg->data;
317 switch (*mc_op) {
318 case PROC_CN_MCAST_LISTEN:
319 atomic_inc(&proc_event_num_listeners);
320 break;
321 case PROC_CN_MCAST_IGNORE:
322 atomic_dec(&proc_event_num_listeners);
323 break;
324 default:
325 err = EINVAL;
326 break;
328 cn_proc_ack(err, msg->seq, msg->ack);
332 * cn_proc_init - initialization entry point
334 * Adds the connector callback to the connector driver.
336 static int __init cn_proc_init(void)
338 int err = cn_add_callback(&cn_proc_event_id,
339 "cn_proc",
340 &cn_proc_mcast_ctl);
341 if (err) {
342 pr_warn("cn_proc failed to register\n");
343 return err;
345 return 0;
348 module_init(cn_proc_init);