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v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 1992 Darren Senn
  4 */
  5
  6/* These are all the functions necessary to implement itimers */
  7
  8#include <linux/mm.h>
  9#include <linux/interrupt.h>
 10#include <linux/syscalls.h>
 11#include <linux/time.h>
 12#include <linux/sched/signal.h>
 13#include <linux/sched/cputime.h>
 14#include <linux/posix-timers.h>
 15#include <linux/hrtimer.h>
 16#include <trace/events/timer.h>
 17#include <linux/compat.h>
 18
 19#include <linux/uaccess.h>
 20
 21/**
 22 * itimer_get_remtime - get remaining time for the timer
 23 *
 24 * @timer: the timer to read
 25 *
 26 * Returns the delta between the expiry time and now, which can be
 27 * less than zero or 1usec for an pending expired timer
 28 */
 29static struct timeval itimer_get_remtime(struct hrtimer *timer)
 30{
 31	ktime_t rem = __hrtimer_get_remaining(timer, true);
 32
 33	/*
 34	 * Racy but safe: if the itimer expires after the above
 35	 * hrtimer_get_remtime() call but before this condition
 36	 * then we return 0 - which is correct.
 37	 */
 38	if (hrtimer_active(timer)) {
 39		if (rem <= 0)
 40			rem = NSEC_PER_USEC;
 41	} else
 42		rem = 0;
 43
 44	return ktime_to_timeval(rem);
 45}
 46
 47static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
 48			   struct itimerval *const value)
 49{
 50	u64 val, interval;
 51	struct cpu_itimer *it = &tsk->signal->it[clock_id];
 52
 53	spin_lock_irq(&tsk->sighand->siglock);
 54
 55	val = it->expires;
 56	interval = it->incr;
 57	if (val) {
 58		u64 t, samples[CPUCLOCK_MAX];
 59
 60		thread_group_sample_cputime(tsk, samples);
 61		t = samples[clock_id];
 62
 63		if (val < t)
 64			/* about to fire */
 65			val = TICK_NSEC;
 66		else
 67			val -= t;
 68	}
 69
 70	spin_unlock_irq(&tsk->sighand->siglock);
 71
 72	value->it_value = ns_to_timeval(val);
 73	value->it_interval = ns_to_timeval(interval);
 74}
 75
 76int do_getitimer(int which, struct itimerval *value)
 77{
 78	struct task_struct *tsk = current;
 79
 80	switch (which) {
 81	case ITIMER_REAL:
 82		spin_lock_irq(&tsk->sighand->siglock);
 83		value->it_value = itimer_get_remtime(&tsk->signal->real_timer);
 84		value->it_interval =
 85			ktime_to_timeval(tsk->signal->it_real_incr);
 86		spin_unlock_irq(&tsk->sighand->siglock);
 87		break;
 88	case ITIMER_VIRTUAL:
 89		get_cpu_itimer(tsk, CPUCLOCK_VIRT, value);
 90		break;
 91	case ITIMER_PROF:
 92		get_cpu_itimer(tsk, CPUCLOCK_PROF, value);
 93		break;
 94	default:
 95		return(-EINVAL);
 96	}
 97	return 0;
 98}
 99
100SYSCALL_DEFINE2(getitimer, int, which, struct itimerval __user *, value)
 
101{
102	int error = -EFAULT;
103	struct itimerval get_buffer;
104
105	if (value) {
106		error = do_getitimer(which, &get_buffer);
107		if (!error &&
108		    copy_to_user(value, &get_buffer, sizeof(get_buffer)))
109			error = -EFAULT;
110	}
 
 
 
 
 
 
 
 
 
111	return error;
112}
113
114#ifdef CONFIG_COMPAT
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
115COMPAT_SYSCALL_DEFINE2(getitimer, int, which,
116		       struct compat_itimerval __user *, it)
117{
118	struct itimerval kit;
119	int error = do_getitimer(which, &kit);
120
121	if (!error && put_compat_itimerval(it, &kit))
122		error = -EFAULT;
123	return error;
124}
125#endif
126
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
127
128/*
129 * The timer is automagically restarted, when interval != 0
 
130 */
131enum hrtimer_restart it_real_fn(struct hrtimer *timer)
132{
133	struct signal_struct *sig =
134		container_of(timer, struct signal_struct, real_timer);
135	struct pid *leader_pid = sig->pids[PIDTYPE_TGID];
136
137	trace_itimer_expire(ITIMER_REAL, leader_pid, 0);
138	kill_pid_info(SIGALRM, SEND_SIG_PRIV, leader_pid);
139
140	return HRTIMER_NORESTART;
141}
142
143static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
144			   const struct itimerval *const value,
145			   struct itimerval *const ovalue)
146{
147	u64 oval, nval, ointerval, ninterval;
148	struct cpu_itimer *it = &tsk->signal->it[clock_id];
149
150	/*
151	 * Use the to_ktime conversion because that clamps the maximum
152	 * value to KTIME_MAX and avoid multiplication overflows.
153	 */
154	nval = ktime_to_ns(timeval_to_ktime(value->it_value));
155	ninterval = ktime_to_ns(timeval_to_ktime(value->it_interval));
156
157	spin_lock_irq(&tsk->sighand->siglock);
158
159	oval = it->expires;
160	ointerval = it->incr;
161	if (oval || nval) {
162		if (nval > 0)
163			nval += TICK_NSEC;
164		set_process_cpu_timer(tsk, clock_id, &nval, &oval);
165	}
166	it->expires = nval;
167	it->incr = ninterval;
168	trace_itimer_state(clock_id == CPUCLOCK_VIRT ?
169			   ITIMER_VIRTUAL : ITIMER_PROF, value, nval);
170
171	spin_unlock_irq(&tsk->sighand->siglock);
172
173	if (ovalue) {
174		ovalue->it_value = ns_to_timeval(oval);
175		ovalue->it_interval = ns_to_timeval(ointerval);
176	}
177}
178
179/*
180 * Returns true if the timeval is in canonical form
181 */
182#define timeval_valid(t) \
183	(((t)->tv_sec >= 0) && (((unsigned long) (t)->tv_usec) < USEC_PER_SEC))
184
185int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
 
186{
187	struct task_struct *tsk = current;
188	struct hrtimer *timer;
189	ktime_t expires;
190
191	/*
192	 * Validate the timevals in value.
193	 */
194	if (!timeval_valid(&value->it_value) ||
195	    !timeval_valid(&value->it_interval))
196		return -EINVAL;
197
198	switch (which) {
199	case ITIMER_REAL:
200again:
201		spin_lock_irq(&tsk->sighand->siglock);
202		timer = &tsk->signal->real_timer;
203		if (ovalue) {
204			ovalue->it_value = itimer_get_remtime(timer);
205			ovalue->it_interval
206				= ktime_to_timeval(tsk->signal->it_real_incr);
207		}
208		/* We are sharing ->siglock with it_real_fn() */
209		if (hrtimer_try_to_cancel(timer) < 0) {
210			spin_unlock_irq(&tsk->sighand->siglock);
211			hrtimer_cancel_wait_running(timer);
212			goto again;
213		}
214		expires = timeval_to_ktime(value->it_value);
215		if (expires != 0) {
216			tsk->signal->it_real_incr =
217				timeval_to_ktime(value->it_interval);
218			hrtimer_start(timer, expires, HRTIMER_MODE_REL);
219		} else
220			tsk->signal->it_real_incr = 0;
221
222		trace_itimer_state(ITIMER_REAL, value, 0);
223		spin_unlock_irq(&tsk->sighand->siglock);
224		break;
225	case ITIMER_VIRTUAL:
226		set_cpu_itimer(tsk, CPUCLOCK_VIRT, value, ovalue);
227		break;
228	case ITIMER_PROF:
229		set_cpu_itimer(tsk, CPUCLOCK_PROF, value, ovalue);
230		break;
231	default:
232		return -EINVAL;
233	}
234	return 0;
235}
236
 
 
 
 
 
 
 
 
 
 
 
237#ifdef __ARCH_WANT_SYS_ALARM
238
239/**
240 * alarm_setitimer - set alarm in seconds
241 *
242 * @seconds:	number of seconds until alarm
243 *		0 disables the alarm
244 *
245 * Returns the remaining time in seconds of a pending timer or 0 when
246 * the timer is not active.
247 *
248 * On 32 bit machines the seconds value is limited to (INT_MAX/2) to avoid
249 * negative timeval settings which would cause immediate expiry.
250 */
251static unsigned int alarm_setitimer(unsigned int seconds)
252{
253	struct itimerval it_new, it_old;
254
255#if BITS_PER_LONG < 64
256	if (seconds > INT_MAX)
257		seconds = INT_MAX;
258#endif
259	it_new.it_value.tv_sec = seconds;
260	it_new.it_value.tv_usec = 0;
261	it_new.it_interval.tv_sec = it_new.it_interval.tv_usec = 0;
262
263	do_setitimer(ITIMER_REAL, &it_new, &it_old);
264
265	/*
266	 * We can't return 0 if we have an alarm pending ...  And we'd
267	 * better return too much than too little anyway
268	 */
269	if ((!it_old.it_value.tv_sec && it_old.it_value.tv_usec) ||
270	      it_old.it_value.tv_usec >= 500000)
271		it_old.it_value.tv_sec++;
272
273	return it_old.it_value.tv_sec;
274}
275
276/*
277 * For backwards compatibility?  This can be done in libc so Alpha
278 * and all newer ports shouldn't need it.
279 */
280SYSCALL_DEFINE1(alarm, unsigned int, seconds)
281{
282	return alarm_setitimer(seconds);
283}
284
285#endif
286
287SYSCALL_DEFINE3(setitimer, int, which, struct itimerval __user *, value,
288		struct itimerval __user *, ovalue)
289{
290	struct itimerval set_buffer, get_buffer;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
291	int error;
292
293	if (value) {
294		if(copy_from_user(&set_buffer, value, sizeof(set_buffer)))
295			return -EFAULT;
 
296	} else {
297		memset(&set_buffer, 0, sizeof(set_buffer));
298		printk_once(KERN_WARNING "%s calls setitimer() with new_value NULL pointer."
299			    " Misfeature support will be removed\n",
300			    current->comm);
301	}
302
303	error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
304	if (error || !ovalue)
305		return error;
306
307	if (copy_to_user(ovalue, &get_buffer, sizeof(get_buffer)))
 
 
 
 
 
 
 
 
 
 
308		return -EFAULT;
 
 
 
 
 
 
 
 
 
 
309	return 0;
310}
311
312#ifdef CONFIG_COMPAT
313COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
314		       struct compat_itimerval __user *, in,
315		       struct compat_itimerval __user *, out)
316{
317	struct itimerval kin, kout;
318	int error;
319
320	if (in) {
321		if (get_compat_itimerval(&kin, in))
322			return -EFAULT;
 
323	} else {
324		memset(&kin, 0, sizeof(kin));
 
 
 
325	}
326
327	error = do_setitimer(which, &kin, out ? &kout : NULL);
328	if (error || !out)
329		return error;
330	if (put_compat_itimerval(out, &kout))
331		return -EFAULT;
332	return 0;
333}
334#endif
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 1992 Darren Senn
  4 */
  5
  6/* These are all the functions necessary to implement itimers */
  7
  8#include <linux/mm.h>
  9#include <linux/interrupt.h>
 10#include <linux/syscalls.h>
 11#include <linux/time.h>
 12#include <linux/sched/signal.h>
 13#include <linux/sched/cputime.h>
 14#include <linux/posix-timers.h>
 15#include <linux/hrtimer.h>
 16#include <trace/events/timer.h>
 17#include <linux/compat.h>
 18
 19#include <linux/uaccess.h>
 20
 21/**
 22 * itimer_get_remtime - get remaining time for the timer
 23 *
 24 * @timer: the timer to read
 25 *
 26 * Returns the delta between the expiry time and now, which can be
 27 * less than zero or 1usec for an pending expired timer
 28 */
 29static struct timespec64 itimer_get_remtime(struct hrtimer *timer)
 30{
 31	ktime_t rem = __hrtimer_get_remaining(timer, true);
 32
 33	/*
 34	 * Racy but safe: if the itimer expires after the above
 35	 * hrtimer_get_remtime() call but before this condition
 36	 * then we return 0 - which is correct.
 37	 */
 38	if (hrtimer_active(timer)) {
 39		if (rem <= 0)
 40			rem = NSEC_PER_USEC;
 41	} else
 42		rem = 0;
 43
 44	return ktime_to_timespec64(rem);
 45}
 46
 47static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
 48			   struct itimerspec64 *const value)
 49{
 50	u64 val, interval;
 51	struct cpu_itimer *it = &tsk->signal->it[clock_id];
 52
 53	spin_lock_irq(&tsk->sighand->siglock);
 54
 55	val = it->expires;
 56	interval = it->incr;
 57	if (val) {
 58		u64 t, samples[CPUCLOCK_MAX];
 59
 60		thread_group_sample_cputime(tsk, samples);
 61		t = samples[clock_id];
 62
 63		if (val < t)
 64			/* about to fire */
 65			val = TICK_NSEC;
 66		else
 67			val -= t;
 68	}
 69
 70	spin_unlock_irq(&tsk->sighand->siglock);
 71
 72	value->it_value = ns_to_timespec64(val);
 73	value->it_interval = ns_to_timespec64(interval);
 74}
 75
 76static int do_getitimer(int which, struct itimerspec64 *value)
 77{
 78	struct task_struct *tsk = current;
 79
 80	switch (which) {
 81	case ITIMER_REAL:
 82		spin_lock_irq(&tsk->sighand->siglock);
 83		value->it_value = itimer_get_remtime(&tsk->signal->real_timer);
 84		value->it_interval =
 85			ktime_to_timespec64(tsk->signal->it_real_incr);
 86		spin_unlock_irq(&tsk->sighand->siglock);
 87		break;
 88	case ITIMER_VIRTUAL:
 89		get_cpu_itimer(tsk, CPUCLOCK_VIRT, value);
 90		break;
 91	case ITIMER_PROF:
 92		get_cpu_itimer(tsk, CPUCLOCK_PROF, value);
 93		break;
 94	default:
 95		return(-EINVAL);
 96	}
 97	return 0;
 98}
 99
100static int put_itimerval(struct __kernel_old_itimerval __user *o,
101			 const struct itimerspec64 *i)
102{
103	struct __kernel_old_itimerval v;
 
104
105	v.it_interval.tv_sec = i->it_interval.tv_sec;
106	v.it_interval.tv_usec = i->it_interval.tv_nsec / NSEC_PER_USEC;
107	v.it_value.tv_sec = i->it_value.tv_sec;
108	v.it_value.tv_usec = i->it_value.tv_nsec / NSEC_PER_USEC;
109	return copy_to_user(o, &v, sizeof(struct __kernel_old_itimerval)) ? -EFAULT : 0;
110}
111
112
113SYSCALL_DEFINE2(getitimer, int, which, struct __kernel_old_itimerval __user *, value)
114{
115	struct itimerspec64 get_buffer;
116	int error = do_getitimer(which, &get_buffer);
117
118	if (!error && put_itimerval(value, &get_buffer))
119		error = -EFAULT;
120	return error;
121}
122
123#if defined(CONFIG_COMPAT) || defined(CONFIG_ALPHA)
124struct old_itimerval32 {
125	struct old_timeval32	it_interval;
126	struct old_timeval32	it_value;
127};
128
129static int put_old_itimerval32(struct old_itimerval32 __user *o,
130			       const struct itimerspec64 *i)
131{
132	struct old_itimerval32 v32;
133
134	v32.it_interval.tv_sec = i->it_interval.tv_sec;
135	v32.it_interval.tv_usec = i->it_interval.tv_nsec / NSEC_PER_USEC;
136	v32.it_value.tv_sec = i->it_value.tv_sec;
137	v32.it_value.tv_usec = i->it_value.tv_nsec / NSEC_PER_USEC;
138	return copy_to_user(o, &v32, sizeof(struct old_itimerval32)) ? -EFAULT : 0;
139}
140
141COMPAT_SYSCALL_DEFINE2(getitimer, int, which,
142		       struct old_itimerval32 __user *, value)
143{
144	struct itimerspec64 get_buffer;
145	int error = do_getitimer(which, &get_buffer);
146
147	if (!error && put_old_itimerval32(value, &get_buffer))
148		error = -EFAULT;
149	return error;
150}
151#endif
152
153/*
154 * Invoked from dequeue_signal() when SIG_ALRM is delivered.
155 *
156 * Restart the ITIMER_REAL timer if it is armed as periodic timer.  Doing
157 * this in the signal delivery path instead of self rearming prevents a DoS
158 * with small increments in the high reolution timer case and reduces timer
159 * noise in general.
160 */
161void posixtimer_rearm_itimer(struct task_struct *tsk)
162{
163	struct hrtimer *tmr = &tsk->signal->real_timer;
164
165	if (!hrtimer_is_queued(tmr) && tsk->signal->it_real_incr != 0) {
166		hrtimer_forward(tmr, tmr->base->get_time(),
167				tsk->signal->it_real_incr);
168		hrtimer_restart(tmr);
169	}
170}
171
172/*
173 * Interval timers are restarted in the signal delivery path.  See
174 * posixtimer_rearm_itimer().
175 */
176enum hrtimer_restart it_real_fn(struct hrtimer *timer)
177{
178	struct signal_struct *sig =
179		container_of(timer, struct signal_struct, real_timer);
180	struct pid *leader_pid = sig->pids[PIDTYPE_TGID];
181
182	trace_itimer_expire(ITIMER_REAL, leader_pid, 0);
183	kill_pid_info(SIGALRM, SEND_SIG_PRIV, leader_pid);
184
185	return HRTIMER_NORESTART;
186}
187
188static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
189			   const struct itimerspec64 *const value,
190			   struct itimerspec64 *const ovalue)
191{
192	u64 oval, nval, ointerval, ninterval;
193	struct cpu_itimer *it = &tsk->signal->it[clock_id];
194
195	nval = timespec64_to_ns(&value->it_value);
196	ninterval = timespec64_to_ns(&value->it_interval);
 
 
 
 
197
198	spin_lock_irq(&tsk->sighand->siglock);
199
200	oval = it->expires;
201	ointerval = it->incr;
202	if (oval || nval) {
203		if (nval > 0)
204			nval += TICK_NSEC;
205		set_process_cpu_timer(tsk, clock_id, &nval, &oval);
206	}
207	it->expires = nval;
208	it->incr = ninterval;
209	trace_itimer_state(clock_id == CPUCLOCK_VIRT ?
210			   ITIMER_VIRTUAL : ITIMER_PROF, value, nval);
211
212	spin_unlock_irq(&tsk->sighand->siglock);
213
214	if (ovalue) {
215		ovalue->it_value = ns_to_timespec64(oval);
216		ovalue->it_interval = ns_to_timespec64(ointerval);
217	}
218}
219
220/*
221 * Returns true if the timeval is in canonical form
222 */
223#define timeval_valid(t) \
224	(((t)->tv_sec >= 0) && (((unsigned long) (t)->tv_usec) < USEC_PER_SEC))
225
226static int do_setitimer(int which, struct itimerspec64 *value,
227			struct itimerspec64 *ovalue)
228{
229	struct task_struct *tsk = current;
230	struct hrtimer *timer;
231	ktime_t expires;
232
 
 
 
 
 
 
 
233	switch (which) {
234	case ITIMER_REAL:
235again:
236		spin_lock_irq(&tsk->sighand->siglock);
237		timer = &tsk->signal->real_timer;
238		if (ovalue) {
239			ovalue->it_value = itimer_get_remtime(timer);
240			ovalue->it_interval
241				= ktime_to_timespec64(tsk->signal->it_real_incr);
242		}
243		/* We are sharing ->siglock with it_real_fn() */
244		if (hrtimer_try_to_cancel(timer) < 0) {
245			spin_unlock_irq(&tsk->sighand->siglock);
246			hrtimer_cancel_wait_running(timer);
247			goto again;
248		}
249		expires = timespec64_to_ktime(value->it_value);
250		if (expires != 0) {
251			tsk->signal->it_real_incr =
252				timespec64_to_ktime(value->it_interval);
253			hrtimer_start(timer, expires, HRTIMER_MODE_REL);
254		} else
255			tsk->signal->it_real_incr = 0;
256
257		trace_itimer_state(ITIMER_REAL, value, 0);
258		spin_unlock_irq(&tsk->sighand->siglock);
259		break;
260	case ITIMER_VIRTUAL:
261		set_cpu_itimer(tsk, CPUCLOCK_VIRT, value, ovalue);
262		break;
263	case ITIMER_PROF:
264		set_cpu_itimer(tsk, CPUCLOCK_PROF, value, ovalue);
265		break;
266	default:
267		return -EINVAL;
268	}
269	return 0;
270}
271
272#ifdef CONFIG_SECURITY_SELINUX
273void clear_itimer(void)
274{
275	struct itimerspec64 v = {};
276	int i;
277
278	for (i = 0; i < 3; i++)
279		do_setitimer(i, &v, NULL);
280}
281#endif
282
283#ifdef __ARCH_WANT_SYS_ALARM
284
285/**
286 * alarm_setitimer - set alarm in seconds
287 *
288 * @seconds:	number of seconds until alarm
289 *		0 disables the alarm
290 *
291 * Returns the remaining time in seconds of a pending timer or 0 when
292 * the timer is not active.
293 *
294 * On 32 bit machines the seconds value is limited to (INT_MAX/2) to avoid
295 * negative timeval settings which would cause immediate expiry.
296 */
297static unsigned int alarm_setitimer(unsigned int seconds)
298{
299	struct itimerspec64 it_new, it_old;
300
301#if BITS_PER_LONG < 64
302	if (seconds > INT_MAX)
303		seconds = INT_MAX;
304#endif
305	it_new.it_value.tv_sec = seconds;
306	it_new.it_value.tv_nsec = 0;
307	it_new.it_interval.tv_sec = it_new.it_interval.tv_nsec = 0;
308
309	do_setitimer(ITIMER_REAL, &it_new, &it_old);
310
311	/*
312	 * We can't return 0 if we have an alarm pending ...  And we'd
313	 * better return too much than too little anyway
314	 */
315	if ((!it_old.it_value.tv_sec && it_old.it_value.tv_nsec) ||
316	      it_old.it_value.tv_nsec >= (NSEC_PER_SEC / 2))
317		it_old.it_value.tv_sec++;
318
319	return it_old.it_value.tv_sec;
320}
321
322/*
323 * For backwards compatibility?  This can be done in libc so Alpha
324 * and all newer ports shouldn't need it.
325 */
326SYSCALL_DEFINE1(alarm, unsigned int, seconds)
327{
328	return alarm_setitimer(seconds);
329}
330
331#endif
332
333static int get_itimerval(struct itimerspec64 *o, const struct __kernel_old_itimerval __user *i)
 
334{
335	struct __kernel_old_itimerval v;
336
337	if (copy_from_user(&v, i, sizeof(struct __kernel_old_itimerval)))
338		return -EFAULT;
339
340	/* Validate the timevals in value. */
341	if (!timeval_valid(&v.it_value) ||
342	    !timeval_valid(&v.it_interval))
343		return -EINVAL;
344
345	o->it_interval.tv_sec = v.it_interval.tv_sec;
346	o->it_interval.tv_nsec = v.it_interval.tv_usec * NSEC_PER_USEC;
347	o->it_value.tv_sec = v.it_value.tv_sec;
348	o->it_value.tv_nsec = v.it_value.tv_usec * NSEC_PER_USEC;
349	return 0;
350}
351
352SYSCALL_DEFINE3(setitimer, int, which, struct __kernel_old_itimerval __user *, value,
353		struct __kernel_old_itimerval __user *, ovalue)
354{
355	struct itimerspec64 set_buffer, get_buffer;
356	int error;
357
358	if (value) {
359		error = get_itimerval(&set_buffer, value);
360		if (error)
361			return error;
362	} else {
363		memset(&set_buffer, 0, sizeof(set_buffer));
364		printk_once(KERN_WARNING "%s calls setitimer() with new_value NULL pointer."
365			    " Misfeature support will be removed\n",
366			    current->comm);
367	}
368
369	error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
370	if (error || !ovalue)
371		return error;
372
373	if (put_itimerval(ovalue, &get_buffer))
374		return -EFAULT;
375	return 0;
376}
377
378#if defined(CONFIG_COMPAT) || defined(CONFIG_ALPHA)
379static int get_old_itimerval32(struct itimerspec64 *o, const struct old_itimerval32 __user *i)
380{
381	struct old_itimerval32 v32;
382
383	if (copy_from_user(&v32, i, sizeof(struct old_itimerval32)))
384		return -EFAULT;
385
386	/* Validate the timevals in value.  */
387	if (!timeval_valid(&v32.it_value) ||
388	    !timeval_valid(&v32.it_interval))
389		return -EINVAL;
390
391	o->it_interval.tv_sec = v32.it_interval.tv_sec;
392	o->it_interval.tv_nsec = v32.it_interval.tv_usec * NSEC_PER_USEC;
393	o->it_value.tv_sec = v32.it_value.tv_sec;
394	o->it_value.tv_nsec = v32.it_value.tv_usec * NSEC_PER_USEC;
395	return 0;
396}
397
 
398COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
399		       struct old_itimerval32 __user *, value,
400		       struct old_itimerval32 __user *, ovalue)
401{
402	struct itimerspec64 set_buffer, get_buffer;
403	int error;
404
405	if (value) {
406		error = get_old_itimerval32(&set_buffer, value);
407		if (error)
408			return error;
409	} else {
410		memset(&set_buffer, 0, sizeof(set_buffer));
411		printk_once(KERN_WARNING "%s calls setitimer() with new_value NULL pointer."
412			    " Misfeature support will be removed\n",
413			    current->comm);
414	}
415
416	error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
417	if (error || !ovalue)
418		return error;
419	if (put_old_itimerval32(ovalue, &get_buffer))
420		return -EFAULT;
421	return 0;
422}
423#endif