xref: /netbsd-src/sys/kern/kern_proc.c (revision 4391d5e9d4f291db41e3b3ba26a01b5e51364aae)
1 /*	$NetBSD: kern_proc.c,v 1.190 2013/11/14 12:07:11 martin Exp $	*/
2 
3 /*-
4  * Copyright (c) 1999, 2006, 2007, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9  * NASA Ames Research Center, and by Andrew Doran.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1982, 1986, 1989, 1991, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  *
61  *	@(#)kern_proc.c	8.7 (Berkeley) 2/14/95
62  */
63 
64 #include <sys/cdefs.h>
65 __KERNEL_RCSID(0, "$NetBSD: kern_proc.c,v 1.190 2013/11/14 12:07:11 martin Exp $");
66 
67 #ifdef _KERNEL_OPT
68 #include "opt_kstack.h"
69 #include "opt_maxuprc.h"
70 #include "opt_dtrace.h"
71 #include "opt_compat_netbsd32.h"
72 #endif
73 
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/kernel.h>
77 #include <sys/proc.h>
78 #include <sys/resourcevar.h>
79 #include <sys/buf.h>
80 #include <sys/acct.h>
81 #include <sys/wait.h>
82 #include <sys/file.h>
83 #include <ufs/ufs/quota.h>
84 #include <sys/uio.h>
85 #include <sys/pool.h>
86 #include <sys/pset.h>
87 #include <sys/mbuf.h>
88 #include <sys/ioctl.h>
89 #include <sys/tty.h>
90 #include <sys/signalvar.h>
91 #include <sys/ras.h>
92 #include <sys/filedesc.h>
93 #include <sys/syscall_stats.h>
94 #include <sys/kauth.h>
95 #include <sys/sleepq.h>
96 #include <sys/atomic.h>
97 #include <sys/kmem.h>
98 #include <sys/dtrace_bsd.h>
99 #include <sys/sysctl.h>
100 #include <sys/exec.h>
101 #include <sys/cpu.h>
102 
103 #include <uvm/uvm_extern.h>
104 
105 #ifdef COMPAT_NETBSD32
106 #include <compat/netbsd32/netbsd32.h>
107 #endif
108 
109 /*
110  * Process lists.
111  */
112 
113 struct proclist		allproc		__cacheline_aligned;
114 struct proclist		zombproc	__cacheline_aligned;
115 
116 kmutex_t *		proc_lock	__cacheline_aligned;
117 
118 /*
119  * pid to proc lookup is done by indexing the pid_table array.
120  * Since pid numbers are only allocated when an empty slot
121  * has been found, there is no need to search any lists ever.
122  * (an orphaned pgrp will lock the slot, a session will lock
123  * the pgrp with the same number.)
124  * If the table is too small it is reallocated with twice the
125  * previous size and the entries 'unzipped' into the two halves.
126  * A linked list of free entries is passed through the pt_proc
127  * field of 'free' items - set odd to be an invalid ptr.
128  */
129 
130 struct pid_table {
131 	struct proc	*pt_proc;
132 	struct pgrp	*pt_pgrp;
133 	pid_t		pt_pid;
134 };
135 #if 1	/* strongly typed cast - should be a noop */
136 static inline uint p2u(struct proc *p) { return (uint)(uintptr_t)p; }
137 #else
138 #define p2u(p) ((uint)p)
139 #endif
140 #define P_VALID(p) (!(p2u(p) & 1))
141 #define P_NEXT(p) (p2u(p) >> 1)
142 #define P_FREE(pid) ((struct proc *)(uintptr_t)((pid) << 1 | 1))
143 
144 /*
145  * Table of process IDs (PIDs).
146  */
147 static struct pid_table *pid_table	__read_mostly;
148 
149 #define	INITIAL_PID_TABLE_SIZE		(1 << 5)
150 
151 /* Table mask, threshold for growing and number of allocated PIDs. */
152 static u_int		pid_tbl_mask	__read_mostly;
153 static u_int		pid_alloc_lim	__read_mostly;
154 static u_int		pid_alloc_cnt	__cacheline_aligned;
155 
156 /* Next free, last free and maximum PIDs. */
157 static u_int		next_free_pt	__cacheline_aligned;
158 static u_int		last_free_pt	__cacheline_aligned;
159 static pid_t		pid_max		__read_mostly;
160 
161 /* Components of the first process -- never freed. */
162 
163 extern struct emul emul_netbsd;	/* defined in kern_exec.c */
164 
165 struct session session0 = {
166 	.s_count = 1,
167 	.s_sid = 0,
168 };
169 struct pgrp pgrp0 = {
170 	.pg_members = LIST_HEAD_INITIALIZER(&pgrp0.pg_members),
171 	.pg_session = &session0,
172 };
173 filedesc_t filedesc0;
174 struct cwdinfo cwdi0 = {
175 	.cwdi_cmask = CMASK,
176 	.cwdi_refcnt = 1,
177 };
178 struct plimit limit0;
179 struct pstats pstat0;
180 struct vmspace vmspace0;
181 struct sigacts sigacts0;
182 struct proc proc0 = {
183 	.p_lwps = LIST_HEAD_INITIALIZER(&proc0.p_lwps),
184 	.p_sigwaiters = LIST_HEAD_INITIALIZER(&proc0.p_sigwaiters),
185 	.p_nlwps = 1,
186 	.p_nrlwps = 1,
187 	.p_nlwpid = 1,		/* must match lwp0.l_lid */
188 	.p_pgrp = &pgrp0,
189 	.p_comm = "system",
190 	/*
191 	 * Set P_NOCLDWAIT so that kernel threads are reparented to init(8)
192 	 * when they exit.  init(8) can easily wait them out for us.
193 	 */
194 	.p_flag = PK_SYSTEM | PK_NOCLDWAIT,
195 	.p_stat = SACTIVE,
196 	.p_nice = NZERO,
197 	.p_emul = &emul_netbsd,
198 	.p_cwdi = &cwdi0,
199 	.p_limit = &limit0,
200 	.p_fd = &filedesc0,
201 	.p_vmspace = &vmspace0,
202 	.p_stats = &pstat0,
203 	.p_sigacts = &sigacts0,
204 #ifdef PROC0_MD_INITIALIZERS
205 	PROC0_MD_INITIALIZERS
206 #endif
207 };
208 kauth_cred_t cred0;
209 
210 static const int	nofile	= NOFILE;
211 static const int	maxuprc	= MAXUPRC;
212 
213 static int sysctl_doeproc(SYSCTLFN_PROTO);
214 static int sysctl_kern_proc_args(SYSCTLFN_PROTO);
215 static void fill_kproc2(struct proc *, struct kinfo_proc2 *, bool);
216 
217 /*
218  * The process list descriptors, used during pid allocation and
219  * by sysctl.  No locking on this data structure is needed since
220  * it is completely static.
221  */
222 const struct proclist_desc proclists[] = {
223 	{ &allproc	},
224 	{ &zombproc	},
225 	{ NULL		},
226 };
227 
228 static struct pgrp *	pg_remove(pid_t);
229 static void		pg_delete(pid_t);
230 static void		orphanpg(struct pgrp *);
231 
232 static specificdata_domain_t proc_specificdata_domain;
233 
234 static pool_cache_t proc_cache;
235 
236 static kauth_listener_t proc_listener;
237 
238 static int
239 proc_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
240     void *arg0, void *arg1, void *arg2, void *arg3)
241 {
242 	struct proc *p;
243 	int result;
244 
245 	result = KAUTH_RESULT_DEFER;
246 	p = arg0;
247 
248 	switch (action) {
249 	case KAUTH_PROCESS_CANSEE: {
250 		enum kauth_process_req req;
251 
252 		req = (enum kauth_process_req)arg1;
253 
254 		switch (req) {
255 		case KAUTH_REQ_PROCESS_CANSEE_ARGS:
256 		case KAUTH_REQ_PROCESS_CANSEE_ENTRY:
257 		case KAUTH_REQ_PROCESS_CANSEE_OPENFILES:
258 			result = KAUTH_RESULT_ALLOW;
259 
260 			break;
261 
262 		case KAUTH_REQ_PROCESS_CANSEE_ENV:
263 			if (kauth_cred_getuid(cred) !=
264 			    kauth_cred_getuid(p->p_cred) ||
265 			    kauth_cred_getuid(cred) !=
266 			    kauth_cred_getsvuid(p->p_cred))
267 				break;
268 
269 			result = KAUTH_RESULT_ALLOW;
270 
271 			break;
272 
273 		default:
274 			break;
275 		}
276 
277 		break;
278 		}
279 
280 	case KAUTH_PROCESS_FORK: {
281 		int lnprocs = (int)(unsigned long)arg2;
282 
283 		/*
284 		 * Don't allow a nonprivileged user to use the last few
285 		 * processes. The variable lnprocs is the current number of
286 		 * processes, maxproc is the limit.
287 		 */
288 		if (__predict_false((lnprocs >= maxproc - 5)))
289 			break;
290 
291 		result = KAUTH_RESULT_ALLOW;
292 
293 		break;
294 		}
295 
296 	case KAUTH_PROCESS_CORENAME:
297 	case KAUTH_PROCESS_STOPFLAG:
298 		if (proc_uidmatch(cred, p->p_cred) == 0)
299 			result = KAUTH_RESULT_ALLOW;
300 
301 		break;
302 
303 	default:
304 		break;
305 	}
306 
307 	return result;
308 }
309 
310 /*
311  * Initialize global process hashing structures.
312  */
313 void
314 procinit(void)
315 {
316 	const struct proclist_desc *pd;
317 	u_int i;
318 #define	LINK_EMPTY ((PID_MAX + INITIAL_PID_TABLE_SIZE) & ~(INITIAL_PID_TABLE_SIZE - 1))
319 
320 	for (pd = proclists; pd->pd_list != NULL; pd++)
321 		LIST_INIT(pd->pd_list);
322 
323 	proc_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
324 	pid_table = kmem_alloc(INITIAL_PID_TABLE_SIZE
325 	    * sizeof(struct pid_table), KM_SLEEP);
326 	pid_tbl_mask = INITIAL_PID_TABLE_SIZE - 1;
327 	pid_max = PID_MAX;
328 
329 	/* Set free list running through table...
330 	   Preset 'use count' above PID_MAX so we allocate pid 1 next. */
331 	for (i = 0; i <= pid_tbl_mask; i++) {
332 		pid_table[i].pt_proc = P_FREE(LINK_EMPTY + i + 1);
333 		pid_table[i].pt_pgrp = 0;
334 		pid_table[i].pt_pid = 0;
335 	}
336 	/* slot 0 is just grabbed */
337 	next_free_pt = 1;
338 	/* Need to fix last entry. */
339 	last_free_pt = pid_tbl_mask;
340 	pid_table[last_free_pt].pt_proc = P_FREE(LINK_EMPTY);
341 	/* point at which we grow table - to avoid reusing pids too often */
342 	pid_alloc_lim = pid_tbl_mask - 1;
343 #undef LINK_EMPTY
344 
345 	proc_specificdata_domain = specificdata_domain_create();
346 	KASSERT(proc_specificdata_domain != NULL);
347 
348 	proc_cache = pool_cache_init(sizeof(struct proc), 0, 0, 0,
349 	    "procpl", NULL, IPL_NONE, NULL, NULL, NULL);
350 
351 	proc_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS,
352 	    proc_listener_cb, NULL);
353 }
354 
355 void
356 procinit_sysctl(void)
357 {
358 	static struct sysctllog *clog;
359 
360 	sysctl_createv(&clog, 0, NULL, NULL,
361 		       CTLFLAG_PERMANENT,
362 		       CTLTYPE_NODE, "kern", NULL,
363 		       NULL, 0, NULL, 0,
364 		       CTL_KERN, CTL_EOL);
365 
366 	sysctl_createv(&clog, 0, NULL, NULL,
367 		       CTLFLAG_PERMANENT,
368 		       CTLTYPE_NODE, "proc",
369 		       SYSCTL_DESCR("System-wide process information"),
370 		       sysctl_doeproc, 0, NULL, 0,
371 		       CTL_KERN, KERN_PROC, CTL_EOL);
372 	sysctl_createv(&clog, 0, NULL, NULL,
373 		       CTLFLAG_PERMANENT,
374 		       CTLTYPE_NODE, "proc2",
375 		       SYSCTL_DESCR("Machine-independent process information"),
376 		       sysctl_doeproc, 0, NULL, 0,
377 		       CTL_KERN, KERN_PROC2, CTL_EOL);
378 	sysctl_createv(&clog, 0, NULL, NULL,
379 		       CTLFLAG_PERMANENT,
380 		       CTLTYPE_NODE, "proc_args",
381 		       SYSCTL_DESCR("Process argument information"),
382 		       sysctl_kern_proc_args, 0, NULL, 0,
383 		       CTL_KERN, KERN_PROC_ARGS, CTL_EOL);
384 
385 	/*
386 	  "nodes" under these:
387 
388 	  KERN_PROC_ALL
389 	  KERN_PROC_PID pid
390 	  KERN_PROC_PGRP pgrp
391 	  KERN_PROC_SESSION sess
392 	  KERN_PROC_TTY tty
393 	  KERN_PROC_UID uid
394 	  KERN_PROC_RUID uid
395 	  KERN_PROC_GID gid
396 	  KERN_PROC_RGID gid
397 
398 	  all in all, probably not worth the effort...
399 	*/
400 }
401 
402 /*
403  * Initialize process 0.
404  */
405 void
406 proc0_init(void)
407 {
408 	struct proc *p;
409 	struct pgrp *pg;
410 	struct rlimit *rlim;
411 	rlim_t lim;
412 	int i;
413 
414 	p = &proc0;
415 	pg = &pgrp0;
416 
417 	mutex_init(&p->p_stmutex, MUTEX_DEFAULT, IPL_HIGH);
418 	mutex_init(&p->p_auxlock, MUTEX_DEFAULT, IPL_NONE);
419 	p->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
420 
421 	rw_init(&p->p_reflock);
422 	cv_init(&p->p_waitcv, "wait");
423 	cv_init(&p->p_lwpcv, "lwpwait");
424 
425 	LIST_INSERT_HEAD(&p->p_lwps, &lwp0, l_sibling);
426 
427 	pid_table[0].pt_proc = p;
428 	LIST_INSERT_HEAD(&allproc, p, p_list);
429 
430 	pid_table[0].pt_pgrp = pg;
431 	LIST_INSERT_HEAD(&pg->pg_members, p, p_pglist);
432 
433 #ifdef __HAVE_SYSCALL_INTERN
434 	(*p->p_emul->e_syscall_intern)(p);
435 #endif
436 
437 	/* Create credentials. */
438 	cred0 = kauth_cred_alloc();
439 	p->p_cred = cred0;
440 
441 	/* Create the CWD info. */
442 	rw_init(&cwdi0.cwdi_lock);
443 
444 	/* Create the limits structures. */
445 	mutex_init(&limit0.pl_lock, MUTEX_DEFAULT, IPL_NONE);
446 
447 	rlim = limit0.pl_rlimit;
448 	for (i = 0; i < __arraycount(limit0.pl_rlimit); i++) {
449 		rlim[i].rlim_cur = RLIM_INFINITY;
450 		rlim[i].rlim_max = RLIM_INFINITY;
451 	}
452 
453 	rlim[RLIMIT_NOFILE].rlim_max = maxfiles;
454 	rlim[RLIMIT_NOFILE].rlim_cur = maxfiles < nofile ? maxfiles : nofile;
455 
456 	rlim[RLIMIT_NPROC].rlim_max = maxproc;
457 	rlim[RLIMIT_NPROC].rlim_cur = maxproc < maxuprc ? maxproc : maxuprc;
458 
459 	lim = MIN(VM_MAXUSER_ADDRESS, ctob((rlim_t)uvmexp.free));
460 	rlim[RLIMIT_RSS].rlim_max = lim;
461 	rlim[RLIMIT_MEMLOCK].rlim_max = lim;
462 	rlim[RLIMIT_MEMLOCK].rlim_cur = lim / 3;
463 
464 	rlim[RLIMIT_NTHR].rlim_max = maxlwp;
465 	rlim[RLIMIT_NTHR].rlim_cur = maxlwp < maxuprc ? maxlwp : maxuprc;
466 
467 	/* Note that default core name has zero length. */
468 	limit0.pl_corename = defcorename;
469 	limit0.pl_cnlen = 0;
470 	limit0.pl_refcnt = 1;
471 	limit0.pl_writeable = false;
472 	limit0.pl_sv_limit = NULL;
473 
474 	/* Configure virtual memory system, set vm rlimits. */
475 	uvm_init_limits(p);
476 
477 	/* Initialize file descriptor table for proc0. */
478 	fd_init(&filedesc0);
479 
480 	/*
481 	 * Initialize proc0's vmspace, which uses the kernel pmap.
482 	 * All kernel processes (which never have user space mappings)
483 	 * share proc0's vmspace, and thus, the kernel pmap.
484 	 */
485 	uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
486 	    trunc_page(VM_MAX_ADDRESS),
487 #ifdef __USING_TOPDOWN_VM
488 	    true
489 #else
490 	    false
491 #endif
492 	    );
493 
494 	/* Initialize signal state for proc0. XXX IPL_SCHED */
495 	mutex_init(&p->p_sigacts->sa_mutex, MUTEX_DEFAULT, IPL_SCHED);
496 	siginit(p);
497 
498 	proc_initspecific(p);
499 	kdtrace_proc_ctor(NULL, p);
500 }
501 
502 /*
503  * Session reference counting.
504  */
505 
506 void
507 proc_sesshold(struct session *ss)
508 {
509 
510 	KASSERT(mutex_owned(proc_lock));
511 	ss->s_count++;
512 }
513 
514 void
515 proc_sessrele(struct session *ss)
516 {
517 
518 	KASSERT(mutex_owned(proc_lock));
519 	/*
520 	 * We keep the pgrp with the same id as the session in order to
521 	 * stop a process being given the same pid.  Since the pgrp holds
522 	 * a reference to the session, it must be a 'zombie' pgrp by now.
523 	 */
524 	if (--ss->s_count == 0) {
525 		struct pgrp *pg;
526 
527 		pg = pg_remove(ss->s_sid);
528 		mutex_exit(proc_lock);
529 
530 		kmem_free(pg, sizeof(struct pgrp));
531 		kmem_free(ss, sizeof(struct session));
532 	} else {
533 		mutex_exit(proc_lock);
534 	}
535 }
536 
537 /*
538  * Check that the specified process group is in the session of the
539  * specified process.
540  * Treats -ve ids as process ids.
541  * Used to validate TIOCSPGRP requests.
542  */
543 int
544 pgid_in_session(struct proc *p, pid_t pg_id)
545 {
546 	struct pgrp *pgrp;
547 	struct session *session;
548 	int error;
549 
550 	mutex_enter(proc_lock);
551 	if (pg_id < 0) {
552 		struct proc *p1 = proc_find(-pg_id);
553 		if (p1 == NULL) {
554 			error = EINVAL;
555 			goto fail;
556 		}
557 		pgrp = p1->p_pgrp;
558 	} else {
559 		pgrp = pgrp_find(pg_id);
560 		if (pgrp == NULL) {
561 			error = EINVAL;
562 			goto fail;
563 		}
564 	}
565 	session = pgrp->pg_session;
566 	error = (session != p->p_pgrp->pg_session) ? EPERM : 0;
567 fail:
568 	mutex_exit(proc_lock);
569 	return error;
570 }
571 
572 /*
573  * p_inferior: is p an inferior of q?
574  */
575 static inline bool
576 p_inferior(struct proc *p, struct proc *q)
577 {
578 
579 	KASSERT(mutex_owned(proc_lock));
580 
581 	for (; p != q; p = p->p_pptr)
582 		if (p->p_pid == 0)
583 			return false;
584 	return true;
585 }
586 
587 /*
588  * proc_find: locate a process by the ID.
589  *
590  * => Must be called with proc_lock held.
591  */
592 proc_t *
593 proc_find_raw(pid_t pid)
594 {
595 	struct pid_table *pt;
596 	proc_t *p;
597 
598 	KASSERT(mutex_owned(proc_lock));
599 	pt = &pid_table[pid & pid_tbl_mask];
600 	p = pt->pt_proc;
601 	if (__predict_false(!P_VALID(p) || pt->pt_pid != pid)) {
602 		return NULL;
603 	}
604 	return p;
605 }
606 
607 proc_t *
608 proc_find(pid_t pid)
609 {
610 	proc_t *p;
611 
612 	p = proc_find_raw(pid);
613 	if (__predict_false(p == NULL)) {
614 		return NULL;
615 	}
616 
617 	/*
618 	 * Only allow live processes to be found by PID.
619 	 * XXX: p_stat might change, since unlocked.
620 	 */
621 	if (__predict_true(p->p_stat == SACTIVE || p->p_stat == SSTOP)) {
622 		return p;
623 	}
624 	return NULL;
625 }
626 
627 /*
628  * pgrp_find: locate a process group by the ID.
629  *
630  * => Must be called with proc_lock held.
631  */
632 struct pgrp *
633 pgrp_find(pid_t pgid)
634 {
635 	struct pgrp *pg;
636 
637 	KASSERT(mutex_owned(proc_lock));
638 
639 	pg = pid_table[pgid & pid_tbl_mask].pt_pgrp;
640 
641 	/*
642 	 * Cannot look up a process group that only exists because the
643 	 * session has not died yet (traditional).
644 	 */
645 	if (pg == NULL || pg->pg_id != pgid || LIST_EMPTY(&pg->pg_members)) {
646 		return NULL;
647 	}
648 	return pg;
649 }
650 
651 static void
652 expand_pid_table(void)
653 {
654 	size_t pt_size, tsz;
655 	struct pid_table *n_pt, *new_pt;
656 	struct proc *proc;
657 	struct pgrp *pgrp;
658 	pid_t pid, rpid;
659 	u_int i;
660 	uint new_pt_mask;
661 
662 	pt_size = pid_tbl_mask + 1;
663 	tsz = pt_size * 2 * sizeof(struct pid_table);
664 	new_pt = kmem_alloc(tsz, KM_SLEEP);
665 	new_pt_mask = pt_size * 2 - 1;
666 
667 	mutex_enter(proc_lock);
668 	if (pt_size != pid_tbl_mask + 1) {
669 		/* Another process beat us to it... */
670 		mutex_exit(proc_lock);
671 		kmem_free(new_pt, tsz);
672 		return;
673 	}
674 
675 	/*
676 	 * Copy entries from old table into new one.
677 	 * If 'pid' is 'odd' we need to place in the upper half,
678 	 * even pid's to the lower half.
679 	 * Free items stay in the low half so we don't have to
680 	 * fixup the reference to them.
681 	 * We stuff free items on the front of the freelist
682 	 * because we can't write to unmodified entries.
683 	 * Processing the table backwards maintains a semblance
684 	 * of issuing pid numbers that increase with time.
685 	 */
686 	i = pt_size - 1;
687 	n_pt = new_pt + i;
688 	for (; ; i--, n_pt--) {
689 		proc = pid_table[i].pt_proc;
690 		pgrp = pid_table[i].pt_pgrp;
691 		if (!P_VALID(proc)) {
692 			/* Up 'use count' so that link is valid */
693 			pid = (P_NEXT(proc) + pt_size) & ~pt_size;
694 			rpid = 0;
695 			proc = P_FREE(pid);
696 			if (pgrp)
697 				pid = pgrp->pg_id;
698 		} else {
699 			pid = pid_table[i].pt_pid;
700 			rpid = pid;
701 		}
702 
703 		/* Save entry in appropriate half of table */
704 		n_pt[pid & pt_size].pt_proc = proc;
705 		n_pt[pid & pt_size].pt_pgrp = pgrp;
706 		n_pt[pid & pt_size].pt_pid = rpid;
707 
708 		/* Put other piece on start of free list */
709 		pid = (pid ^ pt_size) & ~pid_tbl_mask;
710 		n_pt[pid & pt_size].pt_proc =
711 			P_FREE((pid & ~pt_size) | next_free_pt);
712 		n_pt[pid & pt_size].pt_pgrp = 0;
713 		n_pt[pid & pt_size].pt_pid = 0;
714 
715 		next_free_pt = i | (pid & pt_size);
716 		if (i == 0)
717 			break;
718 	}
719 
720 	/* Save old table size and switch tables */
721 	tsz = pt_size * sizeof(struct pid_table);
722 	n_pt = pid_table;
723 	pid_table = new_pt;
724 	pid_tbl_mask = new_pt_mask;
725 
726 	/*
727 	 * pid_max starts as PID_MAX (= 30000), once we have 16384
728 	 * allocated pids we need it to be larger!
729 	 */
730 	if (pid_tbl_mask > PID_MAX) {
731 		pid_max = pid_tbl_mask * 2 + 1;
732 		pid_alloc_lim |= pid_alloc_lim << 1;
733 	} else
734 		pid_alloc_lim <<= 1;	/* doubles number of free slots... */
735 
736 	mutex_exit(proc_lock);
737 	kmem_free(n_pt, tsz);
738 }
739 
740 struct proc *
741 proc_alloc(void)
742 {
743 	struct proc *p;
744 
745 	p = pool_cache_get(proc_cache, PR_WAITOK);
746 	p->p_stat = SIDL;			/* protect against others */
747 	proc_initspecific(p);
748 	kdtrace_proc_ctor(NULL, p);
749 	p->p_pid = -1;
750 	proc_alloc_pid(p);
751 	return p;
752 }
753 
754 /*
755  * proc_alloc_pid: allocate PID and record the given proc 'p' so that
756  * proc_find_raw() can find it by the PID.
757  */
758 
759 pid_t
760 proc_alloc_pid(struct proc *p)
761 {
762 	struct pid_table *pt;
763 	pid_t pid;
764 	int nxt;
765 
766 	for (;;expand_pid_table()) {
767 		if (__predict_false(pid_alloc_cnt >= pid_alloc_lim))
768 			/* ensure pids cycle through 2000+ values */
769 			continue;
770 		mutex_enter(proc_lock);
771 		pt = &pid_table[next_free_pt];
772 #ifdef DIAGNOSTIC
773 		if (__predict_false(P_VALID(pt->pt_proc) || pt->pt_pgrp))
774 			panic("proc_alloc: slot busy");
775 #endif
776 		nxt = P_NEXT(pt->pt_proc);
777 		if (nxt & pid_tbl_mask)
778 			break;
779 		/* Table full - expand (NB last entry not used....) */
780 		mutex_exit(proc_lock);
781 	}
782 
783 	/* pid is 'saved use count' + 'size' + entry */
784 	pid = (nxt & ~pid_tbl_mask) + pid_tbl_mask + 1 + next_free_pt;
785 	if ((uint)pid > (uint)pid_max)
786 		pid &= pid_tbl_mask;
787 	next_free_pt = nxt & pid_tbl_mask;
788 
789 	/* Grab table slot */
790 	pt->pt_proc = p;
791 
792 	KASSERT(pt->pt_pid == 0);
793 	pt->pt_pid = pid;
794 	if (p->p_pid == -1) {
795 		p->p_pid = pid;
796 	}
797 	pid_alloc_cnt++;
798 	mutex_exit(proc_lock);
799 
800 	return pid;
801 }
802 
803 /*
804  * Free a process id - called from proc_free (in kern_exit.c)
805  *
806  * Called with the proc_lock held.
807  */
808 void
809 proc_free_pid(pid_t pid)
810 {
811 	struct pid_table *pt;
812 
813 	KASSERT(mutex_owned(proc_lock));
814 
815 	pt = &pid_table[pid & pid_tbl_mask];
816 
817 	/* save pid use count in slot */
818 	pt->pt_proc = P_FREE(pid & ~pid_tbl_mask);
819 	KASSERT(pt->pt_pid == pid);
820 	pt->pt_pid = 0;
821 
822 	if (pt->pt_pgrp == NULL) {
823 		/* link last freed entry onto ours */
824 		pid &= pid_tbl_mask;
825 		pt = &pid_table[last_free_pt];
826 		pt->pt_proc = P_FREE(P_NEXT(pt->pt_proc) | pid);
827 		pt->pt_pid = 0;
828 		last_free_pt = pid;
829 		pid_alloc_cnt--;
830 	}
831 
832 	atomic_dec_uint(&nprocs);
833 }
834 
835 void
836 proc_free_mem(struct proc *p)
837 {
838 
839 	kdtrace_proc_dtor(NULL, p);
840 	pool_cache_put(proc_cache, p);
841 }
842 
843 /*
844  * proc_enterpgrp: move p to a new or existing process group (and session).
845  *
846  * If we are creating a new pgrp, the pgid should equal
847  * the calling process' pid.
848  * If is only valid to enter a process group that is in the session
849  * of the process.
850  * Also mksess should only be set if we are creating a process group
851  *
852  * Only called from sys_setsid, sys_setpgid and posix_spawn/spawn_return.
853  */
854 int
855 proc_enterpgrp(struct proc *curp, pid_t pid, pid_t pgid, bool mksess)
856 {
857 	struct pgrp *new_pgrp, *pgrp;
858 	struct session *sess;
859 	struct proc *p;
860 	int rval;
861 	pid_t pg_id = NO_PGID;
862 
863 	sess = mksess ? kmem_alloc(sizeof(*sess), KM_SLEEP) : NULL;
864 
865 	/* Allocate data areas we might need before doing any validity checks */
866 	mutex_enter(proc_lock);		/* Because pid_table might change */
867 	if (pid_table[pgid & pid_tbl_mask].pt_pgrp == 0) {
868 		mutex_exit(proc_lock);
869 		new_pgrp = kmem_alloc(sizeof(*new_pgrp), KM_SLEEP);
870 		mutex_enter(proc_lock);
871 	} else
872 		new_pgrp = NULL;
873 	rval = EPERM;	/* most common error (to save typing) */
874 
875 	/* Check pgrp exists or can be created */
876 	pgrp = pid_table[pgid & pid_tbl_mask].pt_pgrp;
877 	if (pgrp != NULL && pgrp->pg_id != pgid)
878 		goto done;
879 
880 	/* Can only set another process under restricted circumstances. */
881 	if (pid != curp->p_pid) {
882 		/* Must exist and be one of our children... */
883 		p = proc_find(pid);
884 		if (p == NULL || !p_inferior(p, curp)) {
885 			rval = ESRCH;
886 			goto done;
887 		}
888 		/* ... in the same session... */
889 		if (sess != NULL || p->p_session != curp->p_session)
890 			goto done;
891 		/* ... existing pgid must be in same session ... */
892 		if (pgrp != NULL && pgrp->pg_session != p->p_session)
893 			goto done;
894 		/* ... and not done an exec. */
895 		if (p->p_flag & PK_EXEC) {
896 			rval = EACCES;
897 			goto done;
898 		}
899 	} else {
900 		/* ... setsid() cannot re-enter a pgrp */
901 		if (mksess && (curp->p_pgid == curp->p_pid ||
902 		    pgrp_find(curp->p_pid)))
903 			goto done;
904 		p = curp;
905 	}
906 
907 	/* Changing the process group/session of a session
908 	   leader is definitely off limits. */
909 	if (SESS_LEADER(p)) {
910 		if (sess == NULL && p->p_pgrp == pgrp)
911 			/* unless it's a definite noop */
912 			rval = 0;
913 		goto done;
914 	}
915 
916 	/* Can only create a process group with id of process */
917 	if (pgrp == NULL && pgid != pid)
918 		goto done;
919 
920 	/* Can only create a session if creating pgrp */
921 	if (sess != NULL && pgrp != NULL)
922 		goto done;
923 
924 	/* Check we allocated memory for a pgrp... */
925 	if (pgrp == NULL && new_pgrp == NULL)
926 		goto done;
927 
928 	/* Don't attach to 'zombie' pgrp */
929 	if (pgrp != NULL && LIST_EMPTY(&pgrp->pg_members))
930 		goto done;
931 
932 	/* Expect to succeed now */
933 	rval = 0;
934 
935 	if (pgrp == p->p_pgrp)
936 		/* nothing to do */
937 		goto done;
938 
939 	/* Ok all setup, link up required structures */
940 
941 	if (pgrp == NULL) {
942 		pgrp = new_pgrp;
943 		new_pgrp = NULL;
944 		if (sess != NULL) {
945 			sess->s_sid = p->p_pid;
946 			sess->s_leader = p;
947 			sess->s_count = 1;
948 			sess->s_ttyvp = NULL;
949 			sess->s_ttyp = NULL;
950 			sess->s_flags = p->p_session->s_flags & ~S_LOGIN_SET;
951 			memcpy(sess->s_login, p->p_session->s_login,
952 			    sizeof(sess->s_login));
953 			p->p_lflag &= ~PL_CONTROLT;
954 		} else {
955 			sess = p->p_pgrp->pg_session;
956 			proc_sesshold(sess);
957 		}
958 		pgrp->pg_session = sess;
959 		sess = NULL;
960 
961 		pgrp->pg_id = pgid;
962 		LIST_INIT(&pgrp->pg_members);
963 #ifdef DIAGNOSTIC
964 		if (__predict_false(pid_table[pgid & pid_tbl_mask].pt_pgrp))
965 			panic("enterpgrp: pgrp table slot in use");
966 		if (__predict_false(mksess && p != curp))
967 			panic("enterpgrp: mksession and p != curproc");
968 #endif
969 		pid_table[pgid & pid_tbl_mask].pt_pgrp = pgrp;
970 		pgrp->pg_jobc = 0;
971 	}
972 
973 	/*
974 	 * Adjust eligibility of affected pgrps to participate in job control.
975 	 * Increment eligibility counts before decrementing, otherwise we
976 	 * could reach 0 spuriously during the first call.
977 	 */
978 	fixjobc(p, pgrp, 1);
979 	fixjobc(p, p->p_pgrp, 0);
980 
981 	/* Interlock with ttread(). */
982 	mutex_spin_enter(&tty_lock);
983 
984 	/* Move process to requested group. */
985 	LIST_REMOVE(p, p_pglist);
986 	if (LIST_EMPTY(&p->p_pgrp->pg_members))
987 		/* defer delete until we've dumped the lock */
988 		pg_id = p->p_pgrp->pg_id;
989 	p->p_pgrp = pgrp;
990 	LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist);
991 
992 	/* Done with the swap; we can release the tty mutex. */
993 	mutex_spin_exit(&tty_lock);
994 
995     done:
996 	if (pg_id != NO_PGID) {
997 		/* Releases proc_lock. */
998 		pg_delete(pg_id);
999 	} else {
1000 		mutex_exit(proc_lock);
1001 	}
1002 	if (sess != NULL)
1003 		kmem_free(sess, sizeof(*sess));
1004 	if (new_pgrp != NULL)
1005 		kmem_free(new_pgrp, sizeof(*new_pgrp));
1006 #ifdef DEBUG_PGRP
1007 	if (__predict_false(rval))
1008 		printf("enterpgrp(%d,%d,%d), curproc %d, rval %d\n",
1009 			pid, pgid, mksess, curp->p_pid, rval);
1010 #endif
1011 	return rval;
1012 }
1013 
1014 /*
1015  * proc_leavepgrp: remove a process from its process group.
1016  *  => must be called with the proc_lock held, which will be released;
1017  */
1018 void
1019 proc_leavepgrp(struct proc *p)
1020 {
1021 	struct pgrp *pgrp;
1022 
1023 	KASSERT(mutex_owned(proc_lock));
1024 
1025 	/* Interlock with ttread() */
1026 	mutex_spin_enter(&tty_lock);
1027 	pgrp = p->p_pgrp;
1028 	LIST_REMOVE(p, p_pglist);
1029 	p->p_pgrp = NULL;
1030 	mutex_spin_exit(&tty_lock);
1031 
1032 	if (LIST_EMPTY(&pgrp->pg_members)) {
1033 		/* Releases proc_lock. */
1034 		pg_delete(pgrp->pg_id);
1035 	} else {
1036 		mutex_exit(proc_lock);
1037 	}
1038 }
1039 
1040 /*
1041  * pg_remove: remove a process group from the table.
1042  *  => must be called with the proc_lock held;
1043  *  => returns process group to free;
1044  */
1045 static struct pgrp *
1046 pg_remove(pid_t pg_id)
1047 {
1048 	struct pgrp *pgrp;
1049 	struct pid_table *pt;
1050 
1051 	KASSERT(mutex_owned(proc_lock));
1052 
1053 	pt = &pid_table[pg_id & pid_tbl_mask];
1054 	pgrp = pt->pt_pgrp;
1055 
1056 	KASSERT(pgrp != NULL);
1057 	KASSERT(pgrp->pg_id == pg_id);
1058 	KASSERT(LIST_EMPTY(&pgrp->pg_members));
1059 
1060 	pt->pt_pgrp = NULL;
1061 
1062 	if (!P_VALID(pt->pt_proc)) {
1063 		/* Orphaned pgrp, put slot onto free list. */
1064 		KASSERT((P_NEXT(pt->pt_proc) & pid_tbl_mask) == 0);
1065 		pg_id &= pid_tbl_mask;
1066 		pt = &pid_table[last_free_pt];
1067 		pt->pt_proc = P_FREE(P_NEXT(pt->pt_proc) | pg_id);
1068 		KASSERT(pt->pt_pid == 0);
1069 		last_free_pt = pg_id;
1070 		pid_alloc_cnt--;
1071 	}
1072 	return pgrp;
1073 }
1074 
1075 /*
1076  * pg_delete: delete and free a process group.
1077  *  => must be called with the proc_lock held, which will be released.
1078  */
1079 static void
1080 pg_delete(pid_t pg_id)
1081 {
1082 	struct pgrp *pg;
1083 	struct tty *ttyp;
1084 	struct session *ss;
1085 
1086 	KASSERT(mutex_owned(proc_lock));
1087 
1088 	pg = pid_table[pg_id & pid_tbl_mask].pt_pgrp;
1089 	if (pg == NULL || pg->pg_id != pg_id || !LIST_EMPTY(&pg->pg_members)) {
1090 		mutex_exit(proc_lock);
1091 		return;
1092 	}
1093 
1094 	ss = pg->pg_session;
1095 
1096 	/* Remove reference (if any) from tty to this process group */
1097 	mutex_spin_enter(&tty_lock);
1098 	ttyp = ss->s_ttyp;
1099 	if (ttyp != NULL && ttyp->t_pgrp == pg) {
1100 		ttyp->t_pgrp = NULL;
1101 		KASSERT(ttyp->t_session == ss);
1102 	}
1103 	mutex_spin_exit(&tty_lock);
1104 
1105 	/*
1106 	 * The leading process group in a session is freed by proc_sessrele(),
1107 	 * if last reference.  Note: proc_sessrele() releases proc_lock.
1108 	 */
1109 	pg = (ss->s_sid != pg->pg_id) ? pg_remove(pg_id) : NULL;
1110 	proc_sessrele(ss);
1111 
1112 	if (pg != NULL) {
1113 		/* Free it, if was not done by proc_sessrele(). */
1114 		kmem_free(pg, sizeof(struct pgrp));
1115 	}
1116 }
1117 
1118 /*
1119  * Adjust pgrp jobc counters when specified process changes process group.
1120  * We count the number of processes in each process group that "qualify"
1121  * the group for terminal job control (those with a parent in a different
1122  * process group of the same session).  If that count reaches zero, the
1123  * process group becomes orphaned.  Check both the specified process'
1124  * process group and that of its children.
1125  * entering == 0 => p is leaving specified group.
1126  * entering == 1 => p is entering specified group.
1127  *
1128  * Call with proc_lock held.
1129  */
1130 void
1131 fixjobc(struct proc *p, struct pgrp *pgrp, int entering)
1132 {
1133 	struct pgrp *hispgrp;
1134 	struct session *mysession = pgrp->pg_session;
1135 	struct proc *child;
1136 
1137 	KASSERT(mutex_owned(proc_lock));
1138 
1139 	/*
1140 	 * Check p's parent to see whether p qualifies its own process
1141 	 * group; if so, adjust count for p's process group.
1142 	 */
1143 	hispgrp = p->p_pptr->p_pgrp;
1144 	if (hispgrp != pgrp && hispgrp->pg_session == mysession) {
1145 		if (entering) {
1146 			pgrp->pg_jobc++;
1147 			p->p_lflag &= ~PL_ORPHANPG;
1148 		} else if (--pgrp->pg_jobc == 0)
1149 			orphanpg(pgrp);
1150 	}
1151 
1152 	/*
1153 	 * Check this process' children to see whether they qualify
1154 	 * their process groups; if so, adjust counts for children's
1155 	 * process groups.
1156 	 */
1157 	LIST_FOREACH(child, &p->p_children, p_sibling) {
1158 		hispgrp = child->p_pgrp;
1159 		if (hispgrp != pgrp && hispgrp->pg_session == mysession &&
1160 		    !P_ZOMBIE(child)) {
1161 			if (entering) {
1162 				child->p_lflag &= ~PL_ORPHANPG;
1163 				hispgrp->pg_jobc++;
1164 			} else if (--hispgrp->pg_jobc == 0)
1165 				orphanpg(hispgrp);
1166 		}
1167 	}
1168 }
1169 
1170 /*
1171  * A process group has become orphaned;
1172  * if there are any stopped processes in the group,
1173  * hang-up all process in that group.
1174  *
1175  * Call with proc_lock held.
1176  */
1177 static void
1178 orphanpg(struct pgrp *pg)
1179 {
1180 	struct proc *p;
1181 
1182 	KASSERT(mutex_owned(proc_lock));
1183 
1184 	LIST_FOREACH(p, &pg->pg_members, p_pglist) {
1185 		if (p->p_stat == SSTOP) {
1186 			p->p_lflag |= PL_ORPHANPG;
1187 			psignal(p, SIGHUP);
1188 			psignal(p, SIGCONT);
1189 		}
1190 	}
1191 }
1192 
1193 #ifdef DDB
1194 #include <ddb/db_output.h>
1195 void pidtbl_dump(void);
1196 void
1197 pidtbl_dump(void)
1198 {
1199 	struct pid_table *pt;
1200 	struct proc *p;
1201 	struct pgrp *pgrp;
1202 	int id;
1203 
1204 	db_printf("pid table %p size %x, next %x, last %x\n",
1205 		pid_table, pid_tbl_mask+1,
1206 		next_free_pt, last_free_pt);
1207 	for (pt = pid_table, id = 0; id <= pid_tbl_mask; id++, pt++) {
1208 		p = pt->pt_proc;
1209 		if (!P_VALID(p) && !pt->pt_pgrp)
1210 			continue;
1211 		db_printf("  id %x: ", id);
1212 		if (P_VALID(p))
1213 			db_printf("slotpid %d proc %p id %d (0x%x) %s\n",
1214 				pt->pt_pid, p, p->p_pid, p->p_pid, p->p_comm);
1215 		else
1216 			db_printf("next %x use %x\n",
1217 				P_NEXT(p) & pid_tbl_mask,
1218 				P_NEXT(p) & ~pid_tbl_mask);
1219 		if ((pgrp = pt->pt_pgrp)) {
1220 			db_printf("\tsession %p, sid %d, count %d, login %s\n",
1221 			    pgrp->pg_session, pgrp->pg_session->s_sid,
1222 			    pgrp->pg_session->s_count,
1223 			    pgrp->pg_session->s_login);
1224 			db_printf("\tpgrp %p, pg_id %d, pg_jobc %d, members %p\n",
1225 			    pgrp, pgrp->pg_id, pgrp->pg_jobc,
1226 			    LIST_FIRST(&pgrp->pg_members));
1227 			LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1228 				db_printf("\t\tpid %d addr %p pgrp %p %s\n",
1229 				    p->p_pid, p, p->p_pgrp, p->p_comm);
1230 			}
1231 		}
1232 	}
1233 }
1234 #endif /* DDB */
1235 
1236 #ifdef KSTACK_CHECK_MAGIC
1237 
1238 #define	KSTACK_MAGIC	0xdeadbeaf
1239 
1240 /* XXX should be per process basis? */
1241 static int	kstackleftmin = KSTACK_SIZE;
1242 static int	kstackleftthres = KSTACK_SIZE / 8;
1243 
1244 void
1245 kstack_setup_magic(const struct lwp *l)
1246 {
1247 	uint32_t *ip;
1248 	uint32_t const *end;
1249 
1250 	KASSERT(l != NULL);
1251 	KASSERT(l != &lwp0);
1252 
1253 	/*
1254 	 * fill all the stack with magic number
1255 	 * so that later modification on it can be detected.
1256 	 */
1257 	ip = (uint32_t *)KSTACK_LOWEST_ADDR(l);
1258 	end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
1259 	for (; ip < end; ip++) {
1260 		*ip = KSTACK_MAGIC;
1261 	}
1262 }
1263 
1264 void
1265 kstack_check_magic(const struct lwp *l)
1266 {
1267 	uint32_t const *ip, *end;
1268 	int stackleft;
1269 
1270 	KASSERT(l != NULL);
1271 
1272 	/* don't check proc0 */ /*XXX*/
1273 	if (l == &lwp0)
1274 		return;
1275 
1276 #ifdef __MACHINE_STACK_GROWS_UP
1277 	/* stack grows upwards (eg. hppa) */
1278 	ip = (uint32_t *)((void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
1279 	end = (uint32_t *)KSTACK_LOWEST_ADDR(l);
1280 	for (ip--; ip >= end; ip--)
1281 		if (*ip != KSTACK_MAGIC)
1282 			break;
1283 
1284 	stackleft = (void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE - (void *)ip;
1285 #else /* __MACHINE_STACK_GROWS_UP */
1286 	/* stack grows downwards (eg. i386) */
1287 	ip = (uint32_t *)KSTACK_LOWEST_ADDR(l);
1288 	end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
1289 	for (; ip < end; ip++)
1290 		if (*ip != KSTACK_MAGIC)
1291 			break;
1292 
1293 	stackleft = ((const char *)ip) - (const char *)KSTACK_LOWEST_ADDR(l);
1294 #endif /* __MACHINE_STACK_GROWS_UP */
1295 
1296 	if (kstackleftmin > stackleft) {
1297 		kstackleftmin = stackleft;
1298 		if (stackleft < kstackleftthres)
1299 			printf("warning: kernel stack left %d bytes"
1300 			    "(pid %u:lid %u)\n", stackleft,
1301 			    (u_int)l->l_proc->p_pid, (u_int)l->l_lid);
1302 	}
1303 
1304 	if (stackleft <= 0) {
1305 		panic("magic on the top of kernel stack changed for "
1306 		    "pid %u, lid %u: maybe kernel stack overflow",
1307 		    (u_int)l->l_proc->p_pid, (u_int)l->l_lid);
1308 	}
1309 }
1310 #endif /* KSTACK_CHECK_MAGIC */
1311 
1312 int
1313 proclist_foreach_call(struct proclist *list,
1314     int (*callback)(struct proc *, void *arg), void *arg)
1315 {
1316 	struct proc marker;
1317 	struct proc *p;
1318 	int ret = 0;
1319 
1320 	marker.p_flag = PK_MARKER;
1321 	mutex_enter(proc_lock);
1322 	for (p = LIST_FIRST(list); ret == 0 && p != NULL;) {
1323 		if (p->p_flag & PK_MARKER) {
1324 			p = LIST_NEXT(p, p_list);
1325 			continue;
1326 		}
1327 		LIST_INSERT_AFTER(p, &marker, p_list);
1328 		ret = (*callback)(p, arg);
1329 		KASSERT(mutex_owned(proc_lock));
1330 		p = LIST_NEXT(&marker, p_list);
1331 		LIST_REMOVE(&marker, p_list);
1332 	}
1333 	mutex_exit(proc_lock);
1334 
1335 	return ret;
1336 }
1337 
1338 int
1339 proc_vmspace_getref(struct proc *p, struct vmspace **vm)
1340 {
1341 
1342 	/* XXXCDC: how should locking work here? */
1343 
1344 	/* curproc exception is for coredump. */
1345 
1346 	if ((p != curproc && (p->p_sflag & PS_WEXIT) != 0) ||
1347 	    (p->p_vmspace->vm_refcnt < 1)) { /* XXX */
1348 		return EFAULT;
1349 	}
1350 
1351 	uvmspace_addref(p->p_vmspace);
1352 	*vm = p->p_vmspace;
1353 
1354 	return 0;
1355 }
1356 
1357 /*
1358  * Acquire a write lock on the process credential.
1359  */
1360 void
1361 proc_crmod_enter(void)
1362 {
1363 	struct lwp *l = curlwp;
1364 	struct proc *p = l->l_proc;
1365 	kauth_cred_t oc;
1366 
1367 	/* Reset what needs to be reset in plimit. */
1368 	if (p->p_limit->pl_corename != defcorename) {
1369 		lim_setcorename(p, defcorename, 0);
1370 	}
1371 
1372 	mutex_enter(p->p_lock);
1373 
1374 	/* Ensure the LWP cached credentials are up to date. */
1375 	if ((oc = l->l_cred) != p->p_cred) {
1376 		kauth_cred_hold(p->p_cred);
1377 		l->l_cred = p->p_cred;
1378 		kauth_cred_free(oc);
1379 	}
1380 }
1381 
1382 /*
1383  * Set in a new process credential, and drop the write lock.  The credential
1384  * must have a reference already.  Optionally, free a no-longer required
1385  * credential.  The scheduler also needs to inspect p_cred, so we also
1386  * briefly acquire the sched state mutex.
1387  */
1388 void
1389 proc_crmod_leave(kauth_cred_t scred, kauth_cred_t fcred, bool sugid)
1390 {
1391 	struct lwp *l = curlwp, *l2;
1392 	struct proc *p = l->l_proc;
1393 	kauth_cred_t oc;
1394 
1395 	KASSERT(mutex_owned(p->p_lock));
1396 
1397 	/* Is there a new credential to set in? */
1398 	if (scred != NULL) {
1399 		p->p_cred = scred;
1400 		LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
1401 			if (l2 != l)
1402 				l2->l_prflag |= LPR_CRMOD;
1403 		}
1404 
1405 		/* Ensure the LWP cached credentials are up to date. */
1406 		if ((oc = l->l_cred) != scred) {
1407 			kauth_cred_hold(scred);
1408 			l->l_cred = scred;
1409 		}
1410 	} else
1411 		oc = NULL;	/* XXXgcc */
1412 
1413 	if (sugid) {
1414 		/*
1415 		 * Mark process as having changed credentials, stops
1416 		 * tracing etc.
1417 		 */
1418 		p->p_flag |= PK_SUGID;
1419 	}
1420 
1421 	mutex_exit(p->p_lock);
1422 
1423 	/* If there is a credential to be released, free it now. */
1424 	if (fcred != NULL) {
1425 		KASSERT(scred != NULL);
1426 		kauth_cred_free(fcred);
1427 		if (oc != scred)
1428 			kauth_cred_free(oc);
1429 	}
1430 }
1431 
1432 /*
1433  * proc_specific_key_create --
1434  *	Create a key for subsystem proc-specific data.
1435  */
1436 int
1437 proc_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor)
1438 {
1439 
1440 	return (specificdata_key_create(proc_specificdata_domain, keyp, dtor));
1441 }
1442 
1443 /*
1444  * proc_specific_key_delete --
1445  *	Delete a key for subsystem proc-specific data.
1446  */
1447 void
1448 proc_specific_key_delete(specificdata_key_t key)
1449 {
1450 
1451 	specificdata_key_delete(proc_specificdata_domain, key);
1452 }
1453 
1454 /*
1455  * proc_initspecific --
1456  *	Initialize a proc's specificdata container.
1457  */
1458 void
1459 proc_initspecific(struct proc *p)
1460 {
1461 	int error __diagused;
1462 
1463 	error = specificdata_init(proc_specificdata_domain, &p->p_specdataref);
1464 	KASSERT(error == 0);
1465 }
1466 
1467 /*
1468  * proc_finispecific --
1469  *	Finalize a proc's specificdata container.
1470  */
1471 void
1472 proc_finispecific(struct proc *p)
1473 {
1474 
1475 	specificdata_fini(proc_specificdata_domain, &p->p_specdataref);
1476 }
1477 
1478 /*
1479  * proc_getspecific --
1480  *	Return proc-specific data corresponding to the specified key.
1481  */
1482 void *
1483 proc_getspecific(struct proc *p, specificdata_key_t key)
1484 {
1485 
1486 	return (specificdata_getspecific(proc_specificdata_domain,
1487 					 &p->p_specdataref, key));
1488 }
1489 
1490 /*
1491  * proc_setspecific --
1492  *	Set proc-specific data corresponding to the specified key.
1493  */
1494 void
1495 proc_setspecific(struct proc *p, specificdata_key_t key, void *data)
1496 {
1497 
1498 	specificdata_setspecific(proc_specificdata_domain,
1499 				 &p->p_specdataref, key, data);
1500 }
1501 
1502 int
1503 proc_uidmatch(kauth_cred_t cred, kauth_cred_t target)
1504 {
1505 	int r = 0;
1506 
1507 	if (kauth_cred_getuid(cred) != kauth_cred_getuid(target) ||
1508 	    kauth_cred_getuid(cred) != kauth_cred_getsvuid(target)) {
1509 		/*
1510 		 * suid proc of ours or proc not ours
1511 		 */
1512 		r = EPERM;
1513 	} else if (kauth_cred_getgid(target) != kauth_cred_getsvgid(target)) {
1514 		/*
1515 		 * sgid proc has sgid back to us temporarily
1516 		 */
1517 		r = EPERM;
1518 	} else {
1519 		/*
1520 		 * our rgid must be in target's group list (ie,
1521 		 * sub-processes started by a sgid process)
1522 		 */
1523 		int ismember = 0;
1524 
1525 		if (kauth_cred_ismember_gid(cred,
1526 		    kauth_cred_getgid(target), &ismember) != 0 ||
1527 		    !ismember)
1528 			r = EPERM;
1529 	}
1530 
1531 	return (r);
1532 }
1533 
1534 /*
1535  * sysctl stuff
1536  */
1537 
1538 #define KERN_PROCSLOP	(5 * sizeof(struct kinfo_proc))
1539 
1540 static const u_int sysctl_flagmap[] = {
1541 	PK_ADVLOCK, P_ADVLOCK,
1542 	PK_EXEC, P_EXEC,
1543 	PK_NOCLDWAIT, P_NOCLDWAIT,
1544 	PK_32, P_32,
1545 	PK_CLDSIGIGN, P_CLDSIGIGN,
1546 	PK_SUGID, P_SUGID,
1547 	0
1548 };
1549 
1550 static const u_int sysctl_sflagmap[] = {
1551 	PS_NOCLDSTOP, P_NOCLDSTOP,
1552 	PS_WEXIT, P_WEXIT,
1553 	PS_STOPFORK, P_STOPFORK,
1554 	PS_STOPEXEC, P_STOPEXEC,
1555 	PS_STOPEXIT, P_STOPEXIT,
1556 	0
1557 };
1558 
1559 static const u_int sysctl_slflagmap[] = {
1560 	PSL_TRACED, P_TRACED,
1561 	PSL_FSTRACE, P_FSTRACE,
1562 	PSL_CHTRACED, P_CHTRACED,
1563 	PSL_SYSCALL, P_SYSCALL,
1564 	0
1565 };
1566 
1567 static const u_int sysctl_lflagmap[] = {
1568 	PL_CONTROLT, P_CONTROLT,
1569 	PL_PPWAIT, P_PPWAIT,
1570 	0
1571 };
1572 
1573 static const u_int sysctl_stflagmap[] = {
1574 	PST_PROFIL, P_PROFIL,
1575 	0
1576 
1577 };
1578 
1579 /* used by kern_lwp also */
1580 const u_int sysctl_lwpflagmap[] = {
1581 	LW_SINTR, L_SINTR,
1582 	LW_SYSTEM, L_SYSTEM,
1583 	0
1584 };
1585 
1586 /*
1587  * Find the most ``active'' lwp of a process and return it for ps display
1588  * purposes
1589  */
1590 static struct lwp *
1591 proc_active_lwp(struct proc *p)
1592 {
1593 	static const int ostat[] = {
1594 		0,
1595 		2,	/* LSIDL */
1596 		6,	/* LSRUN */
1597 		5,	/* LSSLEEP */
1598 		4,	/* LSSTOP */
1599 		0,	/* LSZOMB */
1600 		1,	/* LSDEAD */
1601 		7,	/* LSONPROC */
1602 		3	/* LSSUSPENDED */
1603 	};
1604 
1605 	struct lwp *l, *lp = NULL;
1606 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
1607 		KASSERT(l->l_stat >= 0 && l->l_stat < __arraycount(ostat));
1608 		if (lp == NULL ||
1609 		    ostat[l->l_stat] > ostat[lp->l_stat] ||
1610 		    (ostat[l->l_stat] == ostat[lp->l_stat] &&
1611 		    l->l_cpticks > lp->l_cpticks)) {
1612 			lp = l;
1613 			continue;
1614 		}
1615 	}
1616 	return lp;
1617 }
1618 
1619 static int
1620 sysctl_doeproc(SYSCTLFN_ARGS)
1621 {
1622 	union {
1623 		struct kinfo_proc kproc;
1624 		struct kinfo_proc2 kproc2;
1625 	} *kbuf;
1626 	struct proc *p, *next, *marker;
1627 	char *where, *dp;
1628 	int type, op, arg, error;
1629 	u_int elem_size, kelem_size, elem_count;
1630 	size_t buflen, needed;
1631 	bool match, zombie, mmmbrains;
1632 
1633 	if (namelen == 1 && name[0] == CTL_QUERY)
1634 		return (sysctl_query(SYSCTLFN_CALL(rnode)));
1635 
1636 	dp = where = oldp;
1637 	buflen = where != NULL ? *oldlenp : 0;
1638 	error = 0;
1639 	needed = 0;
1640 	type = rnode->sysctl_num;
1641 
1642 	if (type == KERN_PROC) {
1643 		if (namelen != 2 && !(namelen == 1 && name[0] == KERN_PROC_ALL))
1644 			return (EINVAL);
1645 		op = name[0];
1646 		if (op != KERN_PROC_ALL)
1647 			arg = name[1];
1648 		else
1649 			arg = 0;		/* Quell compiler warning */
1650 		elem_count = 0;	/* Ditto */
1651 		kelem_size = elem_size = sizeof(kbuf->kproc);
1652 	} else {
1653 		if (namelen != 4)
1654 			return (EINVAL);
1655 		op = name[0];
1656 		arg = name[1];
1657 		elem_size = name[2];
1658 		elem_count = name[3];
1659 		kelem_size = sizeof(kbuf->kproc2);
1660 	}
1661 
1662 	sysctl_unlock();
1663 
1664 	kbuf = kmem_alloc(sizeof(*kbuf), KM_SLEEP);
1665 	marker = kmem_alloc(sizeof(*marker), KM_SLEEP);
1666 	marker->p_flag = PK_MARKER;
1667 
1668 	mutex_enter(proc_lock);
1669 	mmmbrains = false;
1670 	for (p = LIST_FIRST(&allproc);; p = next) {
1671 		if (p == NULL) {
1672 			if (!mmmbrains) {
1673 				p = LIST_FIRST(&zombproc);
1674 				mmmbrains = true;
1675 			}
1676 			if (p == NULL)
1677 				break;
1678 		}
1679 		next = LIST_NEXT(p, p_list);
1680 		if ((p->p_flag & PK_MARKER) != 0)
1681 			continue;
1682 
1683 		/*
1684 		 * Skip embryonic processes.
1685 		 */
1686 		if (p->p_stat == SIDL)
1687 			continue;
1688 
1689 		mutex_enter(p->p_lock);
1690 		error = kauth_authorize_process(l->l_cred,
1691 		    KAUTH_PROCESS_CANSEE, p,
1692 		    KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
1693 		if (error != 0) {
1694 			mutex_exit(p->p_lock);
1695 			continue;
1696 		}
1697 
1698 		/*
1699 		 * TODO - make more efficient (see notes below).
1700 		 * do by session.
1701 		 */
1702 		switch (op) {
1703 		case KERN_PROC_PID:
1704 			/* could do this with just a lookup */
1705 			match = (p->p_pid == (pid_t)arg);
1706 			break;
1707 
1708 		case KERN_PROC_PGRP:
1709 			/* could do this by traversing pgrp */
1710 			match = (p->p_pgrp->pg_id == (pid_t)arg);
1711 			break;
1712 
1713 		case KERN_PROC_SESSION:
1714 			match = (p->p_session->s_sid == (pid_t)arg);
1715 			break;
1716 
1717 		case KERN_PROC_TTY:
1718 			match = true;
1719 			if (arg == (int) KERN_PROC_TTY_REVOKE) {
1720 				if ((p->p_lflag & PL_CONTROLT) == 0 ||
1721 				    p->p_session->s_ttyp == NULL ||
1722 				    p->p_session->s_ttyvp != NULL) {
1723 				    	match = false;
1724 				}
1725 			} else if ((p->p_lflag & PL_CONTROLT) == 0 ||
1726 			    p->p_session->s_ttyp == NULL) {
1727 				if ((dev_t)arg != KERN_PROC_TTY_NODEV) {
1728 					match = false;
1729 				}
1730 			} else if (p->p_session->s_ttyp->t_dev != (dev_t)arg) {
1731 				match = false;
1732 			}
1733 			break;
1734 
1735 		case KERN_PROC_UID:
1736 			match = (kauth_cred_geteuid(p->p_cred) == (uid_t)arg);
1737 			break;
1738 
1739 		case KERN_PROC_RUID:
1740 			match = (kauth_cred_getuid(p->p_cred) == (uid_t)arg);
1741 			break;
1742 
1743 		case KERN_PROC_GID:
1744 			match = (kauth_cred_getegid(p->p_cred) == (uid_t)arg);
1745 			break;
1746 
1747 		case KERN_PROC_RGID:
1748 			match = (kauth_cred_getgid(p->p_cred) == (uid_t)arg);
1749 			break;
1750 
1751 		case KERN_PROC_ALL:
1752 			match = true;
1753 			/* allow everything */
1754 			break;
1755 
1756 		default:
1757 			error = EINVAL;
1758 			mutex_exit(p->p_lock);
1759 			goto cleanup;
1760 		}
1761 		if (!match) {
1762 			mutex_exit(p->p_lock);
1763 			continue;
1764 		}
1765 
1766 		/*
1767 		 * Grab a hold on the process.
1768 		 */
1769 		if (mmmbrains) {
1770 			zombie = true;
1771 		} else {
1772 			zombie = !rw_tryenter(&p->p_reflock, RW_READER);
1773 		}
1774 		if (zombie) {
1775 			LIST_INSERT_AFTER(p, marker, p_list);
1776 		}
1777 
1778 		if (buflen >= elem_size &&
1779 		    (type == KERN_PROC || elem_count > 0)) {
1780 			if (type == KERN_PROC) {
1781 				kbuf->kproc.kp_proc = *p;
1782 				fill_eproc(p, &kbuf->kproc.kp_eproc, zombie);
1783 			} else {
1784 				fill_kproc2(p, &kbuf->kproc2, zombie);
1785 				elem_count--;
1786 			}
1787 			mutex_exit(p->p_lock);
1788 			mutex_exit(proc_lock);
1789 			/*
1790 			 * Copy out elem_size, but not larger than kelem_size
1791 			 */
1792 			error = sysctl_copyout(l, kbuf, dp,
1793 			    min(kelem_size, elem_size));
1794 			mutex_enter(proc_lock);
1795 			if (error) {
1796 				goto bah;
1797 			}
1798 			dp += elem_size;
1799 			buflen -= elem_size;
1800 		} else {
1801 			mutex_exit(p->p_lock);
1802 		}
1803 		needed += elem_size;
1804 
1805 		/*
1806 		 * Release reference to process.
1807 		 */
1808 	 	if (zombie) {
1809 			next = LIST_NEXT(marker, p_list);
1810  			LIST_REMOVE(marker, p_list);
1811 		} else {
1812 			rw_exit(&p->p_reflock);
1813 			next = LIST_NEXT(p, p_list);
1814 		}
1815 	}
1816 	mutex_exit(proc_lock);
1817 
1818 	if (where != NULL) {
1819 		*oldlenp = dp - where;
1820 		if (needed > *oldlenp) {
1821 			error = ENOMEM;
1822 			goto out;
1823 		}
1824 	} else {
1825 		needed += KERN_PROCSLOP;
1826 		*oldlenp = needed;
1827 	}
1828 	if (kbuf)
1829 		kmem_free(kbuf, sizeof(*kbuf));
1830 	if (marker)
1831 		kmem_free(marker, sizeof(*marker));
1832 	sysctl_relock();
1833 	return 0;
1834  bah:
1835  	if (zombie)
1836  		LIST_REMOVE(marker, p_list);
1837 	else
1838 		rw_exit(&p->p_reflock);
1839  cleanup:
1840 	mutex_exit(proc_lock);
1841  out:
1842 	if (kbuf)
1843 		kmem_free(kbuf, sizeof(*kbuf));
1844 	if (marker)
1845 		kmem_free(marker, sizeof(*marker));
1846 	sysctl_relock();
1847 	return error;
1848 }
1849 
1850 int
1851 copyin_psstrings(struct proc *p, struct ps_strings *arginfo)
1852 {
1853 
1854 #ifdef COMPAT_NETBSD32
1855 	if (p->p_flag & PK_32) {
1856 		struct ps_strings32 arginfo32;
1857 
1858 		int error = copyin_proc(p, (void *)p->p_psstrp, &arginfo32,
1859 		    sizeof(arginfo32));
1860 		if (error)
1861 			return error;
1862 		arginfo->ps_argvstr = (void *)(uintptr_t)arginfo32.ps_argvstr;
1863 		arginfo->ps_nargvstr = arginfo32.ps_nargvstr;
1864 		arginfo->ps_envstr = (void *)(uintptr_t)arginfo32.ps_envstr;
1865 		arginfo->ps_nenvstr = arginfo32.ps_nenvstr;
1866 		return 0;
1867 	}
1868 #endif
1869 	return copyin_proc(p, (void *)p->p_psstrp, arginfo, sizeof(*arginfo));
1870 }
1871 
1872 static int
1873 copy_procargs_sysctl_cb(void *cookie_, const void *src, size_t off, size_t len)
1874 {
1875 	void **cookie = cookie_;
1876 	struct lwp *l = cookie[0];
1877 	char *dst = cookie[1];
1878 
1879 	return sysctl_copyout(l, src, dst + off, len);
1880 }
1881 
1882 /*
1883  * sysctl helper routine for kern.proc_args pseudo-subtree.
1884  */
1885 static int
1886 sysctl_kern_proc_args(SYSCTLFN_ARGS)
1887 {
1888 	struct ps_strings pss;
1889 	struct proc *p;
1890 	pid_t pid;
1891 	int type, error;
1892 	void *cookie[2];
1893 
1894 	if (namelen == 1 && name[0] == CTL_QUERY)
1895 		return (sysctl_query(SYSCTLFN_CALL(rnode)));
1896 
1897 	if (newp != NULL || namelen != 2)
1898 		return (EINVAL);
1899 	pid = name[0];
1900 	type = name[1];
1901 
1902 	switch (type) {
1903 	case KERN_PROC_ARGV:
1904 	case KERN_PROC_NARGV:
1905 	case KERN_PROC_ENV:
1906 	case KERN_PROC_NENV:
1907 		/* ok */
1908 		break;
1909 	default:
1910 		return (EINVAL);
1911 	}
1912 
1913 	sysctl_unlock();
1914 
1915 	/* check pid */
1916 	mutex_enter(proc_lock);
1917 	if ((p = proc_find(pid)) == NULL) {
1918 		error = EINVAL;
1919 		goto out_locked;
1920 	}
1921 	mutex_enter(p->p_lock);
1922 
1923 	/* Check permission. */
1924 	if (type == KERN_PROC_ARGV || type == KERN_PROC_NARGV)
1925 		error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
1926 		    p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ARGS), NULL, NULL);
1927 	else if (type == KERN_PROC_ENV || type == KERN_PROC_NENV)
1928 		error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
1929 		    p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENV), NULL, NULL);
1930 	else
1931 		error = EINVAL; /* XXXGCC */
1932 	if (error) {
1933 		mutex_exit(p->p_lock);
1934 		goto out_locked;
1935 	}
1936 
1937 	if (oldp == NULL) {
1938 		if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV)
1939 			*oldlenp = sizeof (int);
1940 		else
1941 			*oldlenp = ARG_MAX;	/* XXX XXX XXX */
1942 		error = 0;
1943 		mutex_exit(p->p_lock);
1944 		goto out_locked;
1945 	}
1946 
1947 	/*
1948 	 * Zombies don't have a stack, so we can't read their psstrings.
1949 	 * System processes also don't have a user stack.
1950 	 */
1951 	if (P_ZOMBIE(p) || (p->p_flag & PK_SYSTEM) != 0) {
1952 		error = EINVAL;
1953 		mutex_exit(p->p_lock);
1954 		goto out_locked;
1955 	}
1956 
1957 	error = rw_tryenter(&p->p_reflock, RW_READER) ? 0 : EBUSY;
1958 	mutex_exit(p->p_lock);
1959 	if (error) {
1960 		goto out_locked;
1961 	}
1962 	mutex_exit(proc_lock);
1963 
1964 	if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV) {
1965 		int value;
1966 		if ((error = copyin_psstrings(p, &pss)) == 0) {
1967 			if (type == KERN_PROC_NARGV)
1968 				value = pss.ps_nargvstr;
1969 			else
1970 				value = pss.ps_nenvstr;
1971 			error = sysctl_copyout(l, &value, oldp, sizeof(value));
1972 			*oldlenp = sizeof(value);
1973 		}
1974 	} else {
1975 		cookie[0] = l;
1976 		cookie[1] = oldp;
1977 		error = copy_procargs(p, type, oldlenp,
1978 		    copy_procargs_sysctl_cb, cookie);
1979 	}
1980 	rw_exit(&p->p_reflock);
1981 	sysctl_relock();
1982 	return error;
1983 
1984 out_locked:
1985 	mutex_exit(proc_lock);
1986 	sysctl_relock();
1987 	return error;
1988 }
1989 
1990 int
1991 copy_procargs(struct proc *p, int oid, size_t *limit,
1992     int (*cb)(void *, const void *, size_t, size_t), void *cookie)
1993 {
1994 	struct ps_strings pss;
1995 	size_t len, i, loaded, entry_len;
1996 	struct uio auio;
1997 	struct iovec aiov;
1998 	int error, argvlen;
1999 	char *arg;
2000 	char **argv;
2001 	vaddr_t user_argv;
2002 	struct vmspace *vmspace;
2003 
2004 	/*
2005 	 * Allocate a temporary buffer to hold the argument vector and
2006 	 * the arguments themselve.
2007 	 */
2008 	arg = kmem_alloc(PAGE_SIZE, KM_SLEEP);
2009 	argv = kmem_alloc(PAGE_SIZE, KM_SLEEP);
2010 
2011 	/*
2012 	 * Lock the process down in memory.
2013 	 */
2014 	vmspace = p->p_vmspace;
2015 	uvmspace_addref(vmspace);
2016 
2017 	/*
2018 	 * Read in the ps_strings structure.
2019 	 */
2020 	if ((error = copyin_psstrings(p, &pss)) != 0)
2021 		goto done;
2022 
2023 	/*
2024 	 * Now read the address of the argument vector.
2025 	 */
2026 	switch (oid) {
2027 	case KERN_PROC_ARGV:
2028 		user_argv = (uintptr_t)pss.ps_argvstr;
2029 		argvlen = pss.ps_nargvstr;
2030 		break;
2031 	case KERN_PROC_ENV:
2032 		user_argv = (uintptr_t)pss.ps_envstr;
2033 		argvlen = pss.ps_nenvstr;
2034 		break;
2035 	default:
2036 		error = EINVAL;
2037 		goto done;
2038 	}
2039 
2040 	if (argvlen < 0) {
2041 		error = EIO;
2042 		goto done;
2043 	}
2044 
2045 #ifdef COMPAT_NETBSD32
2046 	if (p->p_flag & PK_32)
2047 		entry_len = sizeof(netbsd32_charp);
2048 	else
2049 #endif
2050 		entry_len = sizeof(char *);
2051 
2052 	/*
2053 	 * Now copy each string.
2054 	 */
2055 	len = 0; /* bytes written to user buffer */
2056 	loaded = 0; /* bytes from argv already processed */
2057 	i = 0; /* To make compiler happy */
2058 
2059 	for (; argvlen; --argvlen) {
2060 		int finished = 0;
2061 		vaddr_t base;
2062 		size_t xlen;
2063 		int j;
2064 
2065 		if (loaded == 0) {
2066 			size_t rem = entry_len * argvlen;
2067 			loaded = MIN(rem, PAGE_SIZE);
2068 			error = copyin_vmspace(vmspace,
2069 			    (const void *)user_argv, argv, loaded);
2070 			if (error)
2071 				break;
2072 			user_argv += loaded;
2073 			i = 0;
2074 		}
2075 
2076 #ifdef COMPAT_NETBSD32
2077 		if (p->p_flag & PK_32) {
2078 			netbsd32_charp *argv32;
2079 
2080 			argv32 = (netbsd32_charp *)argv;
2081 			base = (vaddr_t)NETBSD32PTR64(argv32[i++]);
2082 		} else
2083 #endif
2084 			base = (vaddr_t)argv[i++];
2085 		loaded -= entry_len;
2086 
2087 		/*
2088 		 * The program has messed around with its arguments,
2089 		 * possibly deleting some, and replacing them with
2090 		 * NULL's. Treat this as the last argument and not
2091 		 * a failure.
2092 		 */
2093 		if (base == 0)
2094 			break;
2095 
2096 		while (!finished) {
2097 			xlen = PAGE_SIZE - (base & PAGE_MASK);
2098 
2099 			aiov.iov_base = arg;
2100 			aiov.iov_len = PAGE_SIZE;
2101 			auio.uio_iov = &aiov;
2102 			auio.uio_iovcnt = 1;
2103 			auio.uio_offset = base;
2104 			auio.uio_resid = xlen;
2105 			auio.uio_rw = UIO_READ;
2106 			UIO_SETUP_SYSSPACE(&auio);
2107 			error = uvm_io(&vmspace->vm_map, &auio);
2108 			if (error)
2109 				goto done;
2110 
2111 			/* Look for the end of the string */
2112 			for (j = 0; j < xlen; j++) {
2113 				if (arg[j] == '\0') {
2114 					xlen = j + 1;
2115 					finished = 1;
2116 					break;
2117 				}
2118 			}
2119 
2120 			/* Check for user buffer overflow */
2121 			if (len + xlen > *limit) {
2122 				finished = 1;
2123 				if (len > *limit)
2124 					xlen = 0;
2125 				else
2126 					xlen = *limit - len;
2127 			}
2128 
2129 			/* Copyout the page */
2130 			error = (*cb)(cookie, arg, len, xlen);
2131 			if (error)
2132 				goto done;
2133 
2134 			len += xlen;
2135 			base += xlen;
2136 		}
2137 	}
2138 	*limit = len;
2139 
2140 done:
2141 	kmem_free(argv, PAGE_SIZE);
2142 	kmem_free(arg, PAGE_SIZE);
2143 	uvmspace_free(vmspace);
2144 	return error;
2145 }
2146 
2147 /*
2148  * Fill in an eproc structure for the specified process.
2149  */
2150 void
2151 fill_eproc(struct proc *p, struct eproc *ep, bool zombie)
2152 {
2153 	struct tty *tp;
2154 	struct lwp *l;
2155 
2156 	KASSERT(mutex_owned(proc_lock));
2157 	KASSERT(mutex_owned(p->p_lock));
2158 
2159 	memset(ep, 0, sizeof(*ep));
2160 
2161 	ep->e_paddr = p;
2162 	ep->e_sess = p->p_session;
2163 	if (p->p_cred) {
2164 		kauth_cred_topcred(p->p_cred, &ep->e_pcred);
2165 		kauth_cred_toucred(p->p_cred, &ep->e_ucred);
2166 	}
2167 	if (p->p_stat != SIDL && !P_ZOMBIE(p) && !zombie) {
2168 		struct vmspace *vm = p->p_vmspace;
2169 
2170 		ep->e_vm.vm_rssize = vm_resident_count(vm);
2171 		ep->e_vm.vm_tsize = vm->vm_tsize;
2172 		ep->e_vm.vm_dsize = vm->vm_dsize;
2173 		ep->e_vm.vm_ssize = vm->vm_ssize;
2174 		ep->e_vm.vm_map.size = vm->vm_map.size;
2175 
2176 		/* Pick the primary (first) LWP */
2177 		l = proc_active_lwp(p);
2178 		KASSERT(l != NULL);
2179 		lwp_lock(l);
2180 		if (l->l_wchan)
2181 			strncpy(ep->e_wmesg, l->l_wmesg, WMESGLEN);
2182 		lwp_unlock(l);
2183 	}
2184 	if (p->p_pptr)
2185 		ep->e_ppid = p->p_pptr->p_pid;
2186 	if (p->p_pgrp && p->p_session) {
2187 		ep->e_pgid = p->p_pgrp->pg_id;
2188 		ep->e_jobc = p->p_pgrp->pg_jobc;
2189 		ep->e_sid = p->p_session->s_sid;
2190 		if ((p->p_lflag & PL_CONTROLT) &&
2191 		    (tp = ep->e_sess->s_ttyp)) {
2192 			ep->e_tdev = tp->t_dev;
2193 			ep->e_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PGID;
2194 			ep->e_tsess = tp->t_session;
2195 		} else
2196 			ep->e_tdev = (uint32_t)NODEV;
2197 		ep->e_flag = ep->e_sess->s_ttyvp ? EPROC_CTTY : 0;
2198 		if (SESS_LEADER(p))
2199 			ep->e_flag |= EPROC_SLEADER;
2200 		strncpy(ep->e_login, ep->e_sess->s_login, MAXLOGNAME);
2201 	}
2202 	ep->e_xsize = ep->e_xrssize = 0;
2203 	ep->e_xccount = ep->e_xswrss = 0;
2204 }
2205 
2206 /*
2207  * Fill in a kinfo_proc2 structure for the specified process.
2208  */
2209 static void
2210 fill_kproc2(struct proc *p, struct kinfo_proc2 *ki, bool zombie)
2211 {
2212 	struct tty *tp;
2213 	struct lwp *l, *l2;
2214 	struct timeval ut, st, rt;
2215 	sigset_t ss1, ss2;
2216 	struct rusage ru;
2217 	struct vmspace *vm;
2218 
2219 	KASSERT(mutex_owned(proc_lock));
2220 	KASSERT(mutex_owned(p->p_lock));
2221 
2222 	sigemptyset(&ss1);
2223 	sigemptyset(&ss2);
2224 	memset(ki, 0, sizeof(*ki));
2225 
2226 	ki->p_paddr = PTRTOUINT64(p);
2227 	ki->p_fd = PTRTOUINT64(p->p_fd);
2228 	ki->p_cwdi = PTRTOUINT64(p->p_cwdi);
2229 	ki->p_stats = PTRTOUINT64(p->p_stats);
2230 	ki->p_limit = PTRTOUINT64(p->p_limit);
2231 	ki->p_vmspace = PTRTOUINT64(p->p_vmspace);
2232 	ki->p_sigacts = PTRTOUINT64(p->p_sigacts);
2233 	ki->p_sess = PTRTOUINT64(p->p_session);
2234 	ki->p_tsess = 0;	/* may be changed if controlling tty below */
2235 	ki->p_ru = PTRTOUINT64(&p->p_stats->p_ru);
2236 	ki->p_eflag = 0;
2237 	ki->p_exitsig = p->p_exitsig;
2238 	ki->p_flag = L_INMEM;   /* Process never swapped out */
2239 	ki->p_flag |= sysctl_map_flags(sysctl_flagmap, p->p_flag);
2240 	ki->p_flag |= sysctl_map_flags(sysctl_sflagmap, p->p_sflag);
2241 	ki->p_flag |= sysctl_map_flags(sysctl_slflagmap, p->p_slflag);
2242 	ki->p_flag |= sysctl_map_flags(sysctl_lflagmap, p->p_lflag);
2243 	ki->p_flag |= sysctl_map_flags(sysctl_stflagmap, p->p_stflag);
2244 	ki->p_pid = p->p_pid;
2245 	if (p->p_pptr)
2246 		ki->p_ppid = p->p_pptr->p_pid;
2247 	else
2248 		ki->p_ppid = 0;
2249 	ki->p_uid = kauth_cred_geteuid(p->p_cred);
2250 	ki->p_ruid = kauth_cred_getuid(p->p_cred);
2251 	ki->p_gid = kauth_cred_getegid(p->p_cred);
2252 	ki->p_rgid = kauth_cred_getgid(p->p_cred);
2253 	ki->p_svuid = kauth_cred_getsvuid(p->p_cred);
2254 	ki->p_svgid = kauth_cred_getsvgid(p->p_cred);
2255 	ki->p_ngroups = kauth_cred_ngroups(p->p_cred);
2256 	kauth_cred_getgroups(p->p_cred, ki->p_groups,
2257 	    min(ki->p_ngroups, sizeof(ki->p_groups) / sizeof(ki->p_groups[0])),
2258 	    UIO_SYSSPACE);
2259 
2260 	ki->p_uticks = p->p_uticks;
2261 	ki->p_sticks = p->p_sticks;
2262 	ki->p_iticks = p->p_iticks;
2263 	ki->p_tpgid = NO_PGID;	/* may be changed if controlling tty below */
2264 	ki->p_tracep = PTRTOUINT64(p->p_tracep);
2265 	ki->p_traceflag = p->p_traceflag;
2266 
2267 	memcpy(&ki->p_sigignore, &p->p_sigctx.ps_sigignore,sizeof(ki_sigset_t));
2268 	memcpy(&ki->p_sigcatch, &p->p_sigctx.ps_sigcatch, sizeof(ki_sigset_t));
2269 
2270 	ki->p_cpticks = 0;
2271 	ki->p_pctcpu = p->p_pctcpu;
2272 	ki->p_estcpu = 0;
2273 	ki->p_stat = p->p_stat; /* Will likely be overridden by LWP status */
2274 	ki->p_realstat = p->p_stat;
2275 	ki->p_nice = p->p_nice;
2276 	ki->p_xstat = p->p_xstat;
2277 	ki->p_acflag = p->p_acflag;
2278 
2279 	strncpy(ki->p_comm, p->p_comm,
2280 	    min(sizeof(ki->p_comm), sizeof(p->p_comm)));
2281 	strncpy(ki->p_ename, p->p_emul->e_name, sizeof(ki->p_ename));
2282 
2283 	ki->p_nlwps = p->p_nlwps;
2284 	ki->p_realflag = ki->p_flag;
2285 
2286 	if (p->p_stat != SIDL && !P_ZOMBIE(p) && !zombie) {
2287 		vm = p->p_vmspace;
2288 		ki->p_vm_rssize = vm_resident_count(vm);
2289 		ki->p_vm_tsize = vm->vm_tsize;
2290 		ki->p_vm_dsize = vm->vm_dsize;
2291 		ki->p_vm_ssize = vm->vm_ssize;
2292 		ki->p_vm_vsize = atop(vm->vm_map.size);
2293 		/*
2294 		 * Since the stack is initially mapped mostly with
2295 		 * PROT_NONE and grown as needed, adjust the "mapped size"
2296 		 * to skip the unused stack portion.
2297 		 */
2298 		ki->p_vm_msize =
2299 		    atop(vm->vm_map.size) - vm->vm_issize + vm->vm_ssize;
2300 
2301 		/* Pick the primary (first) LWP */
2302 		l = proc_active_lwp(p);
2303 		KASSERT(l != NULL);
2304 		lwp_lock(l);
2305 		ki->p_nrlwps = p->p_nrlwps;
2306 		ki->p_forw = 0;
2307 		ki->p_back = 0;
2308 		ki->p_addr = PTRTOUINT64(l->l_addr);
2309 		ki->p_stat = l->l_stat;
2310 		ki->p_flag |= sysctl_map_flags(sysctl_lwpflagmap, l->l_flag);
2311 		ki->p_swtime = l->l_swtime;
2312 		ki->p_slptime = l->l_slptime;
2313 		if (l->l_stat == LSONPROC)
2314 			ki->p_schedflags = l->l_cpu->ci_schedstate.spc_flags;
2315 		else
2316 			ki->p_schedflags = 0;
2317 		ki->p_priority = lwp_eprio(l);
2318 		ki->p_usrpri = l->l_priority;
2319 		if (l->l_wchan)
2320 			strncpy(ki->p_wmesg, l->l_wmesg, sizeof(ki->p_wmesg));
2321 		ki->p_wchan = PTRTOUINT64(l->l_wchan);
2322 		ki->p_cpuid = cpu_index(l->l_cpu);
2323 		lwp_unlock(l);
2324 		LIST_FOREACH(l, &p->p_lwps, l_sibling) {
2325 			/* This is hardly correct, but... */
2326 			sigplusset(&l->l_sigpend.sp_set, &ss1);
2327 			sigplusset(&l->l_sigmask, &ss2);
2328 			ki->p_cpticks += l->l_cpticks;
2329 			ki->p_pctcpu += l->l_pctcpu;
2330 			ki->p_estcpu += l->l_estcpu;
2331 		}
2332 	}
2333 	sigplusset(&p->p_sigpend.sp_set, &ss2);
2334 	memcpy(&ki->p_siglist, &ss1, sizeof(ki_sigset_t));
2335 	memcpy(&ki->p_sigmask, &ss2, sizeof(ki_sigset_t));
2336 
2337 	if (p->p_session != NULL) {
2338 		ki->p_sid = p->p_session->s_sid;
2339 		ki->p__pgid = p->p_pgrp->pg_id;
2340 		if (p->p_session->s_ttyvp)
2341 			ki->p_eflag |= EPROC_CTTY;
2342 		if (SESS_LEADER(p))
2343 			ki->p_eflag |= EPROC_SLEADER;
2344 		strncpy(ki->p_login, p->p_session->s_login,
2345 		    min(sizeof ki->p_login - 1, sizeof p->p_session->s_login));
2346 		ki->p_jobc = p->p_pgrp->pg_jobc;
2347 		if ((p->p_lflag & PL_CONTROLT) && (tp = p->p_session->s_ttyp)) {
2348 			ki->p_tdev = tp->t_dev;
2349 			ki->p_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PGID;
2350 			ki->p_tsess = PTRTOUINT64(tp->t_session);
2351 		} else {
2352 			ki->p_tdev = (int32_t)NODEV;
2353 		}
2354 	}
2355 
2356 	if (!P_ZOMBIE(p) && !zombie) {
2357 		ki->p_uvalid = 1;
2358 		ki->p_ustart_sec = p->p_stats->p_start.tv_sec;
2359 		ki->p_ustart_usec = p->p_stats->p_start.tv_usec;
2360 
2361 		calcru(p, &ut, &st, NULL, &rt);
2362 		ki->p_rtime_sec = rt.tv_sec;
2363 		ki->p_rtime_usec = rt.tv_usec;
2364 		ki->p_uutime_sec = ut.tv_sec;
2365 		ki->p_uutime_usec = ut.tv_usec;
2366 		ki->p_ustime_sec = st.tv_sec;
2367 		ki->p_ustime_usec = st.tv_usec;
2368 
2369 		memcpy(&ru, &p->p_stats->p_ru, sizeof(ru));
2370 		ki->p_uru_nvcsw = 0;
2371 		ki->p_uru_nivcsw = 0;
2372 		LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
2373 			ki->p_uru_nvcsw += (l2->l_ncsw - l2->l_nivcsw);
2374 			ki->p_uru_nivcsw += l2->l_nivcsw;
2375 			ruadd(&ru, &l2->l_ru);
2376 		}
2377 		ki->p_uru_maxrss = ru.ru_maxrss;
2378 		ki->p_uru_ixrss = ru.ru_ixrss;
2379 		ki->p_uru_idrss = ru.ru_idrss;
2380 		ki->p_uru_isrss = ru.ru_isrss;
2381 		ki->p_uru_minflt = ru.ru_minflt;
2382 		ki->p_uru_majflt = ru.ru_majflt;
2383 		ki->p_uru_nswap = ru.ru_nswap;
2384 		ki->p_uru_inblock = ru.ru_inblock;
2385 		ki->p_uru_oublock = ru.ru_oublock;
2386 		ki->p_uru_msgsnd = ru.ru_msgsnd;
2387 		ki->p_uru_msgrcv = ru.ru_msgrcv;
2388 		ki->p_uru_nsignals = ru.ru_nsignals;
2389 
2390 		timeradd(&p->p_stats->p_cru.ru_utime,
2391 			 &p->p_stats->p_cru.ru_stime, &ut);
2392 		ki->p_uctime_sec = ut.tv_sec;
2393 		ki->p_uctime_usec = ut.tv_usec;
2394 	}
2395 }
2396