xref: /freebsd/sys/kern/kern_proc.c (revision 8fa113e5fc65fe6abc757f0089f477a87ee4d185) 
1 /*
2  * Copyright (c) 1982, 1986, 1989, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)kern_proc.c	8.7 (Berkeley) 2/14/95
34  * $FreeBSD$
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/lock.h>
41 #include <sys/malloc.h>
42 #include <sys/mutex.h>
43 #include <sys/proc.h>
44 #include <sys/sysctl.h>
45 #include <sys/filedesc.h>
46 #include <sys/tty.h>
47 #include <sys/signalvar.h>
48 #include <sys/sx.h>
49 #include <sys/user.h>
50 #include <sys/jail.h>
51 
52 #include <vm/vm.h>
53 #include <vm/pmap.h>
54 #include <vm/vm_map.h>
55 #include <vm/vm_zone.h>
56 
57 static MALLOC_DEFINE(M_PGRP, "pgrp", "process group header");
58 MALLOC_DEFINE(M_SESSION, "session", "session header");
59 static MALLOC_DEFINE(M_PROC, "proc", "Proc structures");
60 MALLOC_DEFINE(M_SUBPROC, "subproc", "Proc sub-structures");
61 
62 static void pgdelete	__P((struct pgrp *));
63 
64 static void	orphanpg __P((struct pgrp *pg));
65 
66 /*
67  * Other process lists
68  */
69 struct pidhashhead *pidhashtbl;
70 u_long pidhash;
71 struct pgrphashhead *pgrphashtbl;
72 u_long pgrphash;
73 struct proclist allproc;
74 struct proclist zombproc;
75 struct sx allproc_lock;
76 struct sx proctree_lock;
77 vm_zone_t proc_zone;
78 vm_zone_t ithread_zone;
79 
80 /*
81  * Initialize global process hashing structures.
82  */
83 void
84 procinit()
85 {
86 	int i, j;
87 
88 	sx_init(&allproc_lock, "allproc");
89 	sx_init(&proctree_lock, "proctree");
90 	LIST_INIT(&allproc);
91 	LIST_INIT(&zombproc);
92 	pidhashtbl = hashinit(maxproc / 4, M_PROC, &pidhash);
93 	pgrphashtbl = hashinit(maxproc / 4, M_PROC, &pgrphash);
94 	proc_zone = zinit("PROC", sizeof (struct proc), 0, 0, 5);
95 	uihashinit();
96 	/*
97 	 * This should really be a compile time warning, but I do
98 	 * not know of any way to do that...
99 	 */
100 	if (sizeof(struct kinfo_proc) != KINFO_PROC_SIZE) {
101 		printf("This message will repeat for the next 20 seconds\n");
102 		for (i = 0; i < 20; i++) {
103 			printf("WARNING: size of kinfo_proc (%ld) should be %d!!!\n",
104 			    (long)sizeof(struct kinfo_proc), KINFO_PROC_SIZE);
105 			printf("The kinfo_proc structure was changed ");
106 			printf("incorrectly in <sys/user.h>\n");
107 			for (j = 0; j < 0x7ffffff; j++);
108 		}
109 
110 	}
111 }
112 
113 /*
114  * link up a process structure and it's inbuilt threads etc.
115  */
116 void
117 proc_linkup(struct proc *p)
118 {
119 	struct thread *td;
120 
121 	td = &p->p_thread;
122 
123 	/**** lists headed in the proc structure ****/
124 	/* ALL KSEGRPs in this process */
125 	TAILQ_INIT(       &p->p_ksegrps);	     /* all ksegrps in proc */
126 	TAILQ_INSERT_HEAD(&p->p_ksegrps, &p->p_ksegrp, kg_ksegrp);
127 
128 	/* All threads in this process (an optimisation) */
129 	TAILQ_INIT(       &p->p_threads);	     /* all threads in proc */
130 	TAILQ_INSERT_HEAD(&p->p_threads, &p->p_thread, td_plist);
131 
132 	/**** Lists headed in the KSEGROUP structure ****/
133 	/* all thread in this ksegroup */
134 	TAILQ_INIT(       &p->p_ksegrp.kg_threads);
135 	TAILQ_INSERT_HEAD(&p->p_ksegrp.kg_threads, &p->p_thread, td_kglist);
136 
137 	/* All runnable threads not assigned to a particular KSE */
138 	/* XXXKSE THIS MAY GO AWAY.. KSEs are never unassigned */
139 	TAILQ_INIT(       &p->p_ksegrp.kg_runq); /* links with td_runq */
140 
141 	/* All threads presently not runnable (Thread starts this way) */
142 	TAILQ_INIT(       &p->p_ksegrp.kg_slpq); /* links with td_runq */
143 	TAILQ_INSERT_HEAD(&p->p_ksegrp.kg_slpq, &p->p_thread, td_runq);
144 	/*p->p_thread.td_flags &= ~TDF_ONRUNQ;*/
145 
146 	/* all KSEs in this ksegroup */
147 	TAILQ_INIT(       &p->p_ksegrp.kg_kseq);     /* all kses in ksegrp */
148 	TAILQ_INSERT_HEAD(&p->p_ksegrp.kg_kseq, &p->p_kse, ke_kglist);
149 
150 	/* KSE starts out idle *//* XXXKSE */
151 	TAILQ_INIT(       &p->p_ksegrp.kg_rq);     /* all kses in ksegrp */
152 	TAILQ_INIT(       &p->p_ksegrp.kg_iq);     /* all kses in ksegrp */
153 #if 0
154 	TAILQ_INSERT_HEAD(&p->p_ksegrp.kg_iq, &p->p_kse, ke_kgrlist);
155 #endif  /* is running, not idle */
156 	/*p->p_kse.ke_flags &= &KEF_ONRUNQ;*/
157 
158 	/**** Lists headed in the KSE structure ****/
159 	/* runnable threads assigned to this kse */
160 	TAILQ_INIT(       &p->p_kse.ke_runq);	    /* links with td_runq */
161 
162 	p->p_thread.td_proc	= p;
163 	p->p_kse.ke_proc	= p;
164 	p->p_ksegrp.kg_proc	= p;
165 
166 	p->p_thread.td_ksegrp	= &p->p_ksegrp;
167 	p->p_kse.ke_ksegrp	= &p->p_ksegrp;
168 
169 	p->p_thread.td_last_kse	= &p->p_kse;
170 	p->p_thread.td_kse	= &p->p_kse;
171 
172 	p->p_kse.ke_thread	= &p->p_thread;
173 
174 	p->p_ksegrp.kg_runnable = 1;
175 	p->p_ksegrp.kg_kses = 1;
176 	p->p_ksegrp.kg_runq_kses = 1; /* XXXKSE change name */
177 }
178 
179 /*
180  * Is p an inferior of the current process?
181  */
182 int
183 inferior(p)
184 	register struct proc *p;
185 {
186 
187 	sx_assert(&proctree_lock, SX_LOCKED);
188 	for (; p != curproc; p = p->p_pptr)
189 		if (p->p_pid == 0)
190 			return (0);
191 	return (1);
192 }
193 
194 /*
195  * Locate a process by number
196  */
197 struct proc *
198 pfind(pid)
199 	register pid_t pid;
200 {
201 	register struct proc *p;
202 
203 	sx_slock(&allproc_lock);
204 	LIST_FOREACH(p, PIDHASH(pid), p_hash)
205 		if (p->p_pid == pid) {
206 			PROC_LOCK(p);
207 			break;
208 		}
209 	sx_sunlock(&allproc_lock);
210 	return (p);
211 }
212 
213 /*
214  * Locate a process group by number
215  */
216 struct pgrp *
217 pgfind(pgid)
218 	register pid_t pgid;
219 {
220 	register struct pgrp *pgrp;
221 
222 	LIST_FOREACH(pgrp, PGRPHASH(pgid), pg_hash)
223 		if (pgrp->pg_id == pgid)
224 			return (pgrp);
225 	return (NULL);
226 }
227 
228 /*
229  * Move p to a new or existing process group (and session)
230  */
231 int
232 enterpgrp(p, pgid, mksess)
233 	register struct proc *p;
234 	pid_t pgid;
235 	int mksess;
236 {
237 	register struct pgrp *pgrp = pgfind(pgid);
238 	struct pgrp *savegrp;
239 
240 	KASSERT(pgrp == NULL || !mksess,
241 	    ("enterpgrp: setsid into non-empty pgrp"));
242 	KASSERT(!SESS_LEADER(p),
243 	    ("enterpgrp: session leader attempted setpgrp"));
244 
245 	if (pgrp == NULL) {
246 		pid_t savepid = p->p_pid;
247 		struct proc *np;
248 		/*
249 		 * new process group
250 		 */
251 		KASSERT(p->p_pid == pgid,
252 		    ("enterpgrp: new pgrp and pid != pgid"));
253 		if ((np = pfind(savepid)) == NULL || np != p) {
254 			if (np != NULL)
255 				PROC_UNLOCK(np);
256 			return (ESRCH);
257 		}
258 		PROC_UNLOCK(np);
259 		MALLOC(pgrp, struct pgrp *, sizeof(struct pgrp), M_PGRP,
260 		    M_WAITOK);
261 		if (mksess) {
262 			register struct session *sess;
263 
264 			/*
265 			 * new session
266 			 */
267 			MALLOC(sess, struct session *, sizeof(struct session),
268 			    M_SESSION, M_WAITOK);
269 			sess->s_leader = p;
270 			sess->s_sid = p->p_pid;
271 			sess->s_count = 1;
272 			sess->s_ttyvp = NULL;
273 			sess->s_ttyp = NULL;
274 			bcopy(p->p_session->s_login, sess->s_login,
275 			    sizeof(sess->s_login));
276 			PROC_LOCK(p);
277 			p->p_flag &= ~P_CONTROLT;
278 			PROC_UNLOCK(p);
279 			pgrp->pg_session = sess;
280 			KASSERT(p == curproc,
281 			    ("enterpgrp: mksession and p != curproc"));
282 		} else {
283 			pgrp->pg_session = p->p_session;
284 			pgrp->pg_session->s_count++;
285 		}
286 		pgrp->pg_id = pgid;
287 		LIST_INIT(&pgrp->pg_members);
288 		LIST_INSERT_HEAD(PGRPHASH(pgid), pgrp, pg_hash);
289 		pgrp->pg_jobc = 0;
290 		SLIST_INIT(&pgrp->pg_sigiolst);
291 	} else if (pgrp == p->p_pgrp)
292 		return (0);
293 
294 	/*
295 	 * Adjust eligibility of affected pgrps to participate in job control.
296 	 * Increment eligibility counts before decrementing, otherwise we
297 	 * could reach 0 spuriously during the first call.
298 	 */
299 	fixjobc(p, pgrp, 1);
300 	fixjobc(p, p->p_pgrp, 0);
301 
302 	PROC_LOCK(p);
303 	LIST_REMOVE(p, p_pglist);
304 	savegrp = p->p_pgrp;
305 	p->p_pgrp = pgrp;
306 	LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist);
307 	PROC_UNLOCK(p);
308 	if (LIST_EMPTY(&savegrp->pg_members))
309 		pgdelete(savegrp);
310 	return (0);
311 }
312 
313 /*
314  * remove process from process group
315  */
316 int
317 leavepgrp(p)
318 	register struct proc *p;
319 {
320 	struct pgrp *savegrp;
321 
322 	PROC_LOCK(p);
323 	LIST_REMOVE(p, p_pglist);
324 	savegrp = p->p_pgrp;
325 	p->p_pgrp = NULL;
326 	PROC_UNLOCK(p);
327 	if (LIST_EMPTY(&savegrp->pg_members))
328 		pgdelete(savegrp);
329 	return (0);
330 }
331 
332 /*
333  * delete a process group
334  */
335 static void
336 pgdelete(pgrp)
337 	register struct pgrp *pgrp;
338 {
339 
340 	/*
341 	 * Reset any sigio structures pointing to us as a result of
342 	 * F_SETOWN with our pgid.
343 	 */
344 	funsetownlst(&pgrp->pg_sigiolst);
345 
346 	if (pgrp->pg_session->s_ttyp != NULL &&
347 	    pgrp->pg_session->s_ttyp->t_pgrp == pgrp)
348 		pgrp->pg_session->s_ttyp->t_pgrp = NULL;
349 	LIST_REMOVE(pgrp, pg_hash);
350 	if (--pgrp->pg_session->s_count == 0)
351 		FREE(pgrp->pg_session, M_SESSION);
352 	FREE(pgrp, M_PGRP);
353 }
354 
355 /*
356  * Adjust pgrp jobc counters when specified process changes process group.
357  * We count the number of processes in each process group that "qualify"
358  * the group for terminal job control (those with a parent in a different
359  * process group of the same session).  If that count reaches zero, the
360  * process group becomes orphaned.  Check both the specified process'
361  * process group and that of its children.
362  * entering == 0 => p is leaving specified group.
363  * entering == 1 => p is entering specified group.
364  */
365 void
366 fixjobc(p, pgrp, entering)
367 	register struct proc *p;
368 	register struct pgrp *pgrp;
369 	int entering;
370 {
371 	register struct pgrp *hispgrp;
372 	register struct session *mysession = pgrp->pg_session;
373 
374 	/*
375 	 * Check p's parent to see whether p qualifies its own process
376 	 * group; if so, adjust count for p's process group.
377 	 */
378 	sx_slock(&proctree_lock);
379 	if ((hispgrp = p->p_pptr->p_pgrp) != pgrp &&
380 	    hispgrp->pg_session == mysession) {
381 		if (entering)
382 			pgrp->pg_jobc++;
383 		else if (--pgrp->pg_jobc == 0)
384 			orphanpg(pgrp);
385 	}
386 
387 	/*
388 	 * Check this process' children to see whether they qualify
389 	 * their process groups; if so, adjust counts for children's
390 	 * process groups.
391 	 */
392 	LIST_FOREACH(p, &p->p_children, p_sibling)
393 		if ((hispgrp = p->p_pgrp) != pgrp &&
394 		    hispgrp->pg_session == mysession &&
395 		    p->p_stat != SZOMB) {
396 			if (entering)
397 				hispgrp->pg_jobc++;
398 			else if (--hispgrp->pg_jobc == 0)
399 				orphanpg(hispgrp);
400 		}
401 	sx_sunlock(&proctree_lock);
402 }
403 
404 /*
405  * A process group has become orphaned;
406  * if there are any stopped processes in the group,
407  * hang-up all process in that group.
408  */
409 static void
410 orphanpg(pg)
411 	struct pgrp *pg;
412 {
413 	register struct proc *p;
414 
415 	mtx_lock_spin(&sched_lock);
416 	LIST_FOREACH(p, &pg->pg_members, p_pglist) {
417 		if (p->p_stat == SSTOP) {
418 			mtx_unlock_spin(&sched_lock);
419 			LIST_FOREACH(p, &pg->pg_members, p_pglist) {
420 				PROC_LOCK(p);
421 				psignal(p, SIGHUP);
422 				psignal(p, SIGCONT);
423 				PROC_UNLOCK(p);
424 			}
425 			return;
426 		}
427 	}
428 	mtx_unlock_spin(&sched_lock);
429 }
430 
431 #include "opt_ddb.h"
432 #ifdef DDB
433 #include <ddb/ddb.h>
434 
435 DB_SHOW_COMMAND(pgrpdump, pgrpdump)
436 {
437 	register struct pgrp *pgrp;
438 	register struct proc *p;
439 	register int i;
440 
441 	for (i = 0; i <= pgrphash; i++) {
442 		if (!LIST_EMPTY(&pgrphashtbl[i])) {
443 			printf("\tindx %d\n", i);
444 			LIST_FOREACH(pgrp, &pgrphashtbl[i], pg_hash) {
445 				printf(
446 			"\tpgrp %p, pgid %ld, sess %p, sesscnt %d, mem %p\n",
447 				    (void *)pgrp, (long)pgrp->pg_id,
448 				    (void *)pgrp->pg_session,
449 				    pgrp->pg_session->s_count,
450 				    (void *)LIST_FIRST(&pgrp->pg_members));
451 				LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
452 					printf("\t\tpid %ld addr %p pgrp %p\n",
453 					    (long)p->p_pid, (void *)p,
454 					    (void *)p->p_pgrp);
455 				}
456 			}
457 		}
458 	}
459 }
460 #endif /* DDB */
461 
462 /*
463  * Fill in an kinfo_proc structure for the specified process.
464  */
465 void
466 fill_kinfo_proc(p, kp)
467 	struct proc *p;
468 	struct kinfo_proc *kp;
469 {
470 	struct thread *td;
471 	struct tty *tp;
472 	struct session *sp;
473 
474 	bzero(kp, sizeof(*kp));
475 
476 	kp->ki_structsize = sizeof(*kp);
477 	kp->ki_paddr = p;
478 	PROC_LOCK(p);
479 	kp->ki_addr =/* p->p_addr; */0; /* XXXKSE */
480 	kp->ki_args = p->p_args;
481 	kp->ki_tracep = p->p_tracep;
482 	kp->ki_textvp = p->p_textvp;
483 	kp->ki_fd = p->p_fd;
484 	kp->ki_vmspace = p->p_vmspace;
485 	if (p->p_ucred) {
486 		kp->ki_uid = p->p_ucred->cr_uid;
487 		kp->ki_ruid = p->p_ucred->cr_ruid;
488 		kp->ki_svuid = p->p_ucred->cr_svuid;
489 		/* XXX bde doesn't like KI_NGROUPS */
490 		kp->ki_ngroups = min(p->p_ucred->cr_ngroups, KI_NGROUPS);
491 		bcopy(p->p_ucred->cr_groups, kp->ki_groups,
492 		    kp->ki_ngroups * sizeof(gid_t));
493 		kp->ki_rgid = p->p_ucred->cr_rgid;
494 		kp->ki_svgid = p->p_ucred->cr_svgid;
495 	}
496 	if (p->p_procsig) {
497 		kp->ki_sigignore = p->p_procsig->ps_sigignore;
498 		kp->ki_sigcatch = p->p_procsig->ps_sigcatch;
499 	}
500 	mtx_lock_spin(&sched_lock);
501 	if (p->p_stat != SIDL && p->p_stat != SZOMB && p->p_vmspace != NULL) {
502 		struct vmspace *vm = p->p_vmspace;
503 
504 		kp->ki_size = vm->vm_map.size;
505 		kp->ki_rssize = vmspace_resident_count(vm); /*XXX*/
506 		if (p->p_sflag & PS_INMEM)
507 			kp->ki_rssize += UAREA_PAGES;
508 		FOREACH_THREAD_IN_PROC(p, td) /* XXXKSE: thread swapout check */
509 			kp->ki_rssize += KSTACK_PAGES;
510 		kp->ki_swrss = vm->vm_swrss;
511 		kp->ki_tsize = vm->vm_tsize;
512 		kp->ki_dsize = vm->vm_dsize;
513 		kp->ki_ssize = vm->vm_ssize;
514 	}
515 	if ((p->p_sflag & PS_INMEM) && p->p_stats) {
516 		kp->ki_start = p->p_stats->p_start;
517 		kp->ki_rusage = p->p_stats->p_ru;
518 		kp->ki_childtime.tv_sec = p->p_stats->p_cru.ru_utime.tv_sec +
519 		    p->p_stats->p_cru.ru_stime.tv_sec;
520 		kp->ki_childtime.tv_usec = p->p_stats->p_cru.ru_utime.tv_usec +
521 		    p->p_stats->p_cru.ru_stime.tv_usec;
522 	}
523 	if (p->p_thread.td_wmesg != NULL)
524 		strncpy(kp->ki_wmesg, p->p_thread.td_wmesg, sizeof(kp->ki_wmesg) - 1);
525 	if (p->p_stat == SMTX) {
526 		kp->ki_kiflag |= KI_MTXBLOCK;
527 		strncpy(kp->ki_mtxname, p->p_thread.td_mtxname,
528 		    sizeof(kp->ki_mtxname) - 1);
529 	}
530 	kp->ki_stat = p->p_stat;
531 	kp->ki_sflag = p->p_sflag;
532 	kp->ki_swtime = p->p_swtime;
533 	kp->ki_traceflag = p->p_traceflag;
534 	kp->ki_pid = p->p_pid;
535 	/* vvv XXXKSE */
536 	kp->ki_runtime = p->p_runtime;
537 	kp->ki_pctcpu = p->p_kse.ke_pctcpu;
538 	kp->ki_estcpu = p->p_ksegrp.kg_estcpu;
539 	kp->ki_slptime = p->p_ksegrp.kg_slptime;
540 	kp->ki_wchan = p->p_thread.td_wchan;
541 	kp->ki_pri = p->p_ksegrp.kg_pri;
542 	kp->ki_nice = p->p_ksegrp.kg_nice;
543 	kp->ki_rqindex = p->p_kse.ke_rqindex;
544 	kp->ki_oncpu = p->p_kse.ke_oncpu;
545 	kp->ki_lastcpu = p->p_thread.td_lastcpu;
546 	kp->ki_tdflags = p->p_thread.td_flags;
547 	kp->ki_pcb = p->p_thread.td_pcb;
548 	kp->ki_kstack = (void *)p->p_thread.td_kstack;
549 	/* ^^^ XXXKSE */
550 	mtx_unlock_spin(&sched_lock);
551 	sp = NULL;
552 	if (p->p_pgrp) {
553 		kp->ki_pgid = p->p_pgrp->pg_id;
554 		kp->ki_jobc = p->p_pgrp->pg_jobc;
555 		sp = p->p_pgrp->pg_session;
556 
557 		if (sp != NULL) {
558 			kp->ki_sid = sp->s_sid;
559 			strncpy(kp->ki_login, sp->s_login,
560 			    sizeof(kp->ki_login) - 1);
561 			if (sp->s_ttyvp)
562 				kp->ki_kiflag = KI_CTTY;
563 			if (SESS_LEADER(p))
564 				kp->ki_kiflag |= KI_SLEADER;
565 		}
566 	}
567 	if ((p->p_flag & P_CONTROLT) && sp && ((tp = sp->s_ttyp) != NULL)) {
568 		kp->ki_tdev = dev2udev(tp->t_dev);
569 		kp->ki_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PID;
570 		if (tp->t_session)
571 			kp->ki_tsid = tp->t_session->s_sid;
572 	} else
573 		kp->ki_tdev = NOUDEV;
574 	if (p->p_comm[0] != '\0') {
575 		strncpy(kp->ki_comm, p->p_comm, sizeof(kp->ki_comm) - 1);
576 		strncpy(kp->ki_ocomm, p->p_comm, sizeof(kp->ki_ocomm) - 1);
577 	}
578 	kp->ki_siglist = p->p_siglist;
579 	kp->ki_sigmask = p->p_sigmask;
580 	kp->ki_xstat = p->p_xstat;
581 	kp->ki_acflag = p->p_acflag;
582 	kp->ki_flag = p->p_flag;
583 	/* If jailed(p->p_ucred), emulate the old P_JAILED flag. */
584 	if (jailed(p->p_ucred))
585 		kp->ki_flag |= P_JAILED;
586 	kp->ki_lock = p->p_lock;
587 	if (p->p_pptr)
588 		kp->ki_ppid = p->p_pptr->p_pid;
589 	PROC_UNLOCK(p);
590 }
591 
592 /*
593  * Locate a zombie process by number
594  */
595 struct proc *
596 zpfind(pid_t pid)
597 {
598 	struct proc *p;
599 
600 	sx_slock(&allproc_lock);
601 	LIST_FOREACH(p, &zombproc, p_list)
602 		if (p->p_pid == pid) {
603 			PROC_LOCK(p);
604 			break;
605 		}
606 	sx_sunlock(&allproc_lock);
607 	return (p);
608 }
609 
610 
611 static int
612 sysctl_out_proc(struct proc *p, struct sysctl_req *req, int doingzomb)
613 {
614 	struct kinfo_proc kinfo_proc;
615 	int error;
616 	struct proc *np;
617 	pid_t pid = p->p_pid;
618 
619 	fill_kinfo_proc(p, &kinfo_proc);
620 	error = SYSCTL_OUT(req, (caddr_t)&kinfo_proc, sizeof(kinfo_proc));
621 	if (error)
622 		return (error);
623 	if (doingzomb)
624 		np = zpfind(pid);
625 	else {
626 		if (pid == 0)
627 			return (0);
628 		np = pfind(pid);
629 	}
630 	if (np == NULL)
631 		return EAGAIN;
632 	if (np != p) {
633 		PROC_UNLOCK(np);
634 		return EAGAIN;
635 	}
636 	PROC_UNLOCK(np);
637 	return (0);
638 }
639 
640 static int
641 sysctl_kern_proc(SYSCTL_HANDLER_ARGS)
642 {
643 	int *name = (int*) arg1;
644 	u_int namelen = arg2;
645 	struct proc *p;
646 	int doingzomb;
647 	int error = 0;
648 
649 	if (oidp->oid_number == KERN_PROC_PID) {
650 		if (namelen != 1)
651 			return (EINVAL);
652 		p = pfind((pid_t)name[0]);
653 		if (!p)
654 			return (0);
655 		if (p_cansee(curproc, p)) {
656 			PROC_UNLOCK(p);
657 			return (0);
658 		}
659 		PROC_UNLOCK(p);
660 		error = sysctl_out_proc(p, req, 0);
661 		return (error);
662 	}
663 	if (oidp->oid_number == KERN_PROC_ALL && !namelen)
664 		;
665 	else if (oidp->oid_number != KERN_PROC_ALL && namelen == 1)
666 		;
667 	else
668 		return (EINVAL);
669 
670 	if (!req->oldptr) {
671 		/* overestimate by 5 procs */
672 		error = SYSCTL_OUT(req, 0, sizeof (struct kinfo_proc) * 5);
673 		if (error)
674 			return (error);
675 	}
676 	sx_slock(&allproc_lock);
677 	for (doingzomb=0 ; doingzomb < 2 ; doingzomb++) {
678 		if (!doingzomb)
679 			p = LIST_FIRST(&allproc);
680 		else
681 			p = LIST_FIRST(&zombproc);
682 		for (; p != 0; p = LIST_NEXT(p, p_list)) {
683 			/*
684 			 * Show a user only appropriate processes.
685 			 */
686 			if (p_cansee(curproc, p))
687 				continue;
688 			/*
689 			 * Skip embryonic processes.
690 			 */
691 			if (p->p_stat == SIDL)
692 				continue;
693 			/*
694 			 * TODO - make more efficient (see notes below).
695 			 * do by session.
696 			 */
697 			switch (oidp->oid_number) {
698 
699 			case KERN_PROC_PGRP:
700 				/* could do this by traversing pgrp */
701 				if (p->p_pgrp == NULL ||
702 				    p->p_pgrp->pg_id != (pid_t)name[0])
703 					continue;
704 				break;
705 
706 			case KERN_PROC_TTY:
707 				if ((p->p_flag & P_CONTROLT) == 0 ||
708 				    p->p_session == NULL ||
709 				    p->p_session->s_ttyp == NULL ||
710 				    dev2udev(p->p_session->s_ttyp->t_dev) !=
711 					(udev_t)name[0])
712 					continue;
713 				break;
714 
715 			case KERN_PROC_UID:
716 				if (p->p_ucred == NULL ||
717 				    p->p_ucred->cr_uid != (uid_t)name[0])
718 					continue;
719 				break;
720 
721 			case KERN_PROC_RUID:
722 				if (p->p_ucred == NULL ||
723 				    p->p_ucred->cr_ruid != (uid_t)name[0])
724 					continue;
725 				break;
726 			}
727 
728 			if (p_cansee(curproc, p))
729 				continue;
730 
731 			error = sysctl_out_proc(p, req, doingzomb);
732 			if (error) {
733 				sx_sunlock(&allproc_lock);
734 				return (error);
735 			}
736 		}
737 	}
738 	sx_sunlock(&allproc_lock);
739 	return (0);
740 }
741 
742 /*
743  * This sysctl allows a process to retrieve the argument list or process
744  * title for another process without groping around in the address space
745  * of the other process.  It also allow a process to set its own "process
746  * title to a string of its own choice.
747  */
748 static int
749 sysctl_kern_proc_args(SYSCTL_HANDLER_ARGS)
750 {
751 	int *name = (int*) arg1;
752 	u_int namelen = arg2;
753 	struct proc *p;
754 	struct pargs *pa;
755 	int error = 0;
756 
757 	if (namelen != 1)
758 		return (EINVAL);
759 
760 	p = pfind((pid_t)name[0]);
761 	if (!p)
762 		return (0);
763 
764 	if ((!ps_argsopen) && p_cansee(curproc, p)) {
765 		PROC_UNLOCK(p);
766 		return (0);
767 	}
768 	PROC_UNLOCK(p);
769 
770 	if (req->newptr && curproc != p)
771 		return (EPERM);
772 
773 	if (req->oldptr && p->p_args != NULL)
774 		error = SYSCTL_OUT(req, p->p_args->ar_args, p->p_args->ar_length);
775 	if (req->newptr == NULL)
776 		return (error);
777 
778 	PROC_LOCK(p);
779 	pa = p->p_args;
780 	p->p_args = NULL;
781 	PROC_UNLOCK(p);
782 	if (pa != NULL && --pa->ar_ref == 0)
783 		FREE(pa, M_PARGS);
784 
785 	if (req->newlen + sizeof(struct pargs) > ps_arg_cache_limit)
786 		return (error);
787 
788 	MALLOC(pa, struct pargs *, sizeof(struct pargs) + req->newlen,
789 	    M_PARGS, M_WAITOK);
790 	pa->ar_ref = 1;
791 	pa->ar_length = req->newlen;
792 	error = SYSCTL_IN(req, pa->ar_args, req->newlen);
793 	if (!error) {
794 		PROC_LOCK(p);
795 		p->p_args = pa;
796 		PROC_UNLOCK(p);
797 	} else
798 		FREE(pa, M_PARGS);
799 	return (error);
800 }
801 
802 SYSCTL_NODE(_kern, KERN_PROC, proc, CTLFLAG_RD,  0, "Process table");
803 
804 SYSCTL_PROC(_kern_proc, KERN_PROC_ALL, all, CTLFLAG_RD|CTLTYPE_STRUCT,
805 	0, 0, sysctl_kern_proc, "S,proc", "Return entire process table");
806 
807 SYSCTL_NODE(_kern_proc, KERN_PROC_PGRP, pgrp, CTLFLAG_RD,
808 	sysctl_kern_proc, "Process table");
809 
810 SYSCTL_NODE(_kern_proc, KERN_PROC_TTY, tty, CTLFLAG_RD,
811 	sysctl_kern_proc, "Process table");
812 
813 SYSCTL_NODE(_kern_proc, KERN_PROC_UID, uid, CTLFLAG_RD,
814 	sysctl_kern_proc, "Process table");
815 
816 SYSCTL_NODE(_kern_proc, KERN_PROC_RUID, ruid, CTLFLAG_RD,
817 	sysctl_kern_proc, "Process table");
818 
819 SYSCTL_NODE(_kern_proc, KERN_PROC_PID, pid, CTLFLAG_RD,
820 	sysctl_kern_proc, "Process table");
821 
822 SYSCTL_NODE(_kern_proc, KERN_PROC_ARGS, args, CTLFLAG_RW | CTLFLAG_ANYBODY,
823 	sysctl_kern_proc_args, "Process argument list");
824