xref: /netbsd-src/sys/kern/kern_proc.c (revision e7ac2a8b5bd66fa2e050809de09a075c36a7014d)
1 /*	$NetBSD: kern_proc.c,v 1.260 2020/09/05 16:30:12 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 1999, 2006, 2007, 2008, 2020 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 1.260 2020/09/05 16:30:12 riastradh 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 #include "opt_kaslr.h"
73 #endif
74 
75 #if defined(__HAVE_COMPAT_NETBSD32) && !defined(COMPAT_NETBSD32) \
76     && !defined(_RUMPKERNEL)
77 #define COMPAT_NETBSD32
78 #endif
79 
80 #include <sys/param.h>
81 #include <sys/systm.h>
82 #include <sys/kernel.h>
83 #include <sys/proc.h>
84 #include <sys/resourcevar.h>
85 #include <sys/buf.h>
86 #include <sys/acct.h>
87 #include <sys/wait.h>
88 #include <sys/file.h>
89 #include <ufs/ufs/quota.h>
90 #include <sys/uio.h>
91 #include <sys/pool.h>
92 #include <sys/pset.h>
93 #include <sys/ioctl.h>
94 #include <sys/tty.h>
95 #include <sys/signalvar.h>
96 #include <sys/ras.h>
97 #include <sys/filedesc.h>
98 #include <sys/syscall_stats.h>
99 #include <sys/kauth.h>
100 #include <sys/sleepq.h>
101 #include <sys/atomic.h>
102 #include <sys/kmem.h>
103 #include <sys/namei.h>
104 #include <sys/dtrace_bsd.h>
105 #include <sys/sysctl.h>
106 #include <sys/exec.h>
107 #include <sys/cpu.h>
108 #include <sys/compat_stub.h>
109 #include <sys/futex.h>
110 #include <sys/pserialize.h>
111 
112 #include <uvm/uvm_extern.h>
113 
114 /*
115  * Process lists.
116  */
117 
118 struct proclist		allproc		__cacheline_aligned;
119 struct proclist		zombproc	__cacheline_aligned;
120 
121  kmutex_t		proc_lock	__cacheline_aligned;
122 static pserialize_t	proc_psz;
123 
124 /*
125  * pid to lwp/proc lookup is done by indexing the pid_table array.
126  * Since pid numbers are only allocated when an empty slot
127  * has been found, there is no need to search any lists ever.
128  * (an orphaned pgrp will lock the slot, a session will lock
129  * the pgrp with the same number.)
130  * If the table is too small it is reallocated with twice the
131  * previous size and the entries 'unzipped' into the two halves.
132  * A linked list of free entries is passed through the pt_lwp
133  * field of 'free' items - set odd to be an invalid ptr.  Two
134  * additional bits are also used to indicate if the slot is
135  * currently occupied by a proc or lwp, and if the PID is
136  * hidden from certain kinds of lookups.  We thus require a
137  * minimum alignment for proc and lwp structures (LWPs are
138  * at least 32-byte aligned).
139  */
140 
141 struct pid_table {
142 	uintptr_t	pt_slot;
143 	struct pgrp	*pt_pgrp;
144 	pid_t		pt_pid;
145 };
146 
147 #define	PT_F_FREE		((uintptr_t)__BIT(0))
148 #define	PT_F_LWP		0	/* pseudo-flag */
149 #define	PT_F_PROC		((uintptr_t)__BIT(1))
150 
151 #define	PT_F_TYPEBITS		(PT_F_FREE|PT_F_PROC)
152 #define	PT_F_ALLBITS		(PT_F_FREE|PT_F_PROC)
153 
154 #define	PT_VALID(s)		(((s) & PT_F_FREE) == 0)
155 #define	PT_RESERVED(s)		((s) == 0)
156 #define	PT_NEXT(s)		((u_int)(s) >> 1)
157 #define	PT_SET_FREE(pid)	(((pid) << 1) | PT_F_FREE)
158 #define	PT_SET_LWP(l)		((uintptr_t)(l))
159 #define	PT_SET_PROC(p)		(((uintptr_t)(p)) | PT_F_PROC)
160 #define	PT_SET_RESERVED		0
161 #define	PT_GET_LWP(s)		((struct lwp *)((s) & ~PT_F_ALLBITS))
162 #define	PT_GET_PROC(s)		((struct proc *)((s) & ~PT_F_ALLBITS))
163 #define	PT_GET_TYPE(s)		((s) & PT_F_TYPEBITS)
164 #define	PT_IS_LWP(s)		(PT_GET_TYPE(s) == PT_F_LWP && (s) != 0)
165 #define	PT_IS_PROC(s)		(PT_GET_TYPE(s) == PT_F_PROC)
166 
167 #define	MIN_PROC_ALIGNMENT	(PT_F_ALLBITS + 1)
168 
169 /*
170  * Table of process IDs (PIDs).
171  */
172 static struct pid_table *pid_table	__read_mostly;
173 
174 #define	INITIAL_PID_TABLE_SIZE		(1 << 5)
175 
176 /* Table mask, threshold for growing and number of allocated PIDs. */
177 static u_int		pid_tbl_mask	__read_mostly;
178 static u_int		pid_alloc_lim	__read_mostly;
179 static u_int		pid_alloc_cnt	__cacheline_aligned;
180 
181 /* Next free, last free and maximum PIDs. */
182 static u_int		next_free_pt	__cacheline_aligned;
183 static u_int		last_free_pt	__cacheline_aligned;
184 static pid_t		pid_max		__read_mostly;
185 
186 /* Components of the first process -- never freed. */
187 
188 extern struct emul emul_netbsd;	/* defined in kern_exec.c */
189 
190 struct session session0 = {
191 	.s_count = 1,
192 	.s_sid = 0,
193 };
194 struct pgrp pgrp0 = {
195 	.pg_members = LIST_HEAD_INITIALIZER(&pgrp0.pg_members),
196 	.pg_session = &session0,
197 };
198 filedesc_t filedesc0;
199 struct cwdinfo cwdi0 = {
200 	.cwdi_cmask = CMASK,
201 	.cwdi_refcnt = 1,
202 };
203 struct plimit limit0;
204 struct pstats pstat0;
205 struct vmspace vmspace0;
206 struct sigacts sigacts0;
207 struct proc proc0 = {
208 	.p_lwps = LIST_HEAD_INITIALIZER(&proc0.p_lwps),
209 	.p_sigwaiters = LIST_HEAD_INITIALIZER(&proc0.p_sigwaiters),
210 	.p_nlwps = 1,
211 	.p_nrlwps = 1,
212 	.p_pgrp = &pgrp0,
213 	.p_comm = "system",
214 	/*
215 	 * Set P_NOCLDWAIT so that kernel threads are reparented to init(8)
216 	 * when they exit.  init(8) can easily wait them out for us.
217 	 */
218 	.p_flag = PK_SYSTEM | PK_NOCLDWAIT,
219 	.p_stat = SACTIVE,
220 	.p_nice = NZERO,
221 	.p_emul = &emul_netbsd,
222 	.p_cwdi = &cwdi0,
223 	.p_limit = &limit0,
224 	.p_fd = &filedesc0,
225 	.p_vmspace = &vmspace0,
226 	.p_stats = &pstat0,
227 	.p_sigacts = &sigacts0,
228 #ifdef PROC0_MD_INITIALIZERS
229 	PROC0_MD_INITIALIZERS
230 #endif
231 };
232 kauth_cred_t cred0;
233 
234 static const int	nofile	= NOFILE;
235 static const int	maxuprc	= MAXUPRC;
236 
237 static int sysctl_doeproc(SYSCTLFN_PROTO);
238 static int sysctl_kern_proc_args(SYSCTLFN_PROTO);
239 static int sysctl_security_expose_address(SYSCTLFN_PROTO);
240 
241 #ifdef KASLR
242 static int kern_expose_address = 0;
243 #else
244 static int kern_expose_address = 1;
245 #endif
246 /*
247  * The process list descriptors, used during pid allocation and
248  * by sysctl.  No locking on this data structure is needed since
249  * it is completely static.
250  */
251 const struct proclist_desc proclists[] = {
252 	{ &allproc	},
253 	{ &zombproc	},
254 	{ NULL		},
255 };
256 
257 static struct pgrp *	pg_remove(pid_t);
258 static void		pg_delete(pid_t);
259 static void		orphanpg(struct pgrp *);
260 
261 static specificdata_domain_t proc_specificdata_domain;
262 
263 static pool_cache_t proc_cache;
264 
265 static kauth_listener_t proc_listener;
266 
267 static void fill_proc(const struct proc *, struct proc *, bool);
268 static int fill_pathname(struct lwp *, pid_t, void *, size_t *);
269 static int fill_cwd(struct lwp *, pid_t, void *, size_t *);
270 
271 static int
272 proc_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
273     void *arg0, void *arg1, void *arg2, void *arg3)
274 {
275 	struct proc *p;
276 	int result;
277 
278 	result = KAUTH_RESULT_DEFER;
279 	p = arg0;
280 
281 	switch (action) {
282 	case KAUTH_PROCESS_CANSEE: {
283 		enum kauth_process_req req;
284 
285 		req = (enum kauth_process_req)(uintptr_t)arg1;
286 
287 		switch (req) {
288 		case KAUTH_REQ_PROCESS_CANSEE_ARGS:
289 		case KAUTH_REQ_PROCESS_CANSEE_ENTRY:
290 		case KAUTH_REQ_PROCESS_CANSEE_OPENFILES:
291 		case KAUTH_REQ_PROCESS_CANSEE_EPROC:
292 			result = KAUTH_RESULT_ALLOW;
293 			break;
294 
295 		case KAUTH_REQ_PROCESS_CANSEE_ENV:
296 			if (kauth_cred_getuid(cred) !=
297 			    kauth_cred_getuid(p->p_cred) ||
298 			    kauth_cred_getuid(cred) !=
299 			    kauth_cred_getsvuid(p->p_cred))
300 				break;
301 
302 			result = KAUTH_RESULT_ALLOW;
303 
304 			break;
305 
306 		case KAUTH_REQ_PROCESS_CANSEE_KPTR:
307 			if (!kern_expose_address)
308 				break;
309 
310 			if (kern_expose_address == 1 && !(p->p_flag & PK_KMEM))
311 				break;
312 
313 			result = KAUTH_RESULT_ALLOW;
314 
315 			break;
316 
317 		default:
318 			break;
319 		}
320 
321 		break;
322 		}
323 
324 	case KAUTH_PROCESS_FORK: {
325 		int lnprocs = (int)(unsigned long)arg2;
326 
327 		/*
328 		 * Don't allow a nonprivileged user to use the last few
329 		 * processes. The variable lnprocs is the current number of
330 		 * processes, maxproc is the limit.
331 		 */
332 		if (__predict_false((lnprocs >= maxproc - 5)))
333 			break;
334 
335 		result = KAUTH_RESULT_ALLOW;
336 
337 		break;
338 		}
339 
340 	case KAUTH_PROCESS_CORENAME:
341 	case KAUTH_PROCESS_STOPFLAG:
342 		if (proc_uidmatch(cred, p->p_cred) == 0)
343 			result = KAUTH_RESULT_ALLOW;
344 
345 		break;
346 
347 	default:
348 		break;
349 	}
350 
351 	return result;
352 }
353 
354 static int
355 proc_ctor(void *arg __unused, void *obj, int flags __unused)
356 {
357 	memset(obj, 0, sizeof(struct proc));
358 	return 0;
359 }
360 
361 static pid_t proc_alloc_pid_slot(struct proc *, uintptr_t);
362 
363 /*
364  * Initialize global process hashing structures.
365  */
366 void
367 procinit(void)
368 {
369 	const struct proclist_desc *pd;
370 	u_int i;
371 #define	LINK_EMPTY ((PID_MAX + INITIAL_PID_TABLE_SIZE) & ~(INITIAL_PID_TABLE_SIZE - 1))
372 
373 	for (pd = proclists; pd->pd_list != NULL; pd++)
374 		LIST_INIT(pd->pd_list);
375 
376 	mutex_init(&proc_lock, MUTEX_DEFAULT, IPL_NONE);
377 
378 	proc_psz = pserialize_create();
379 
380 	pid_table = kmem_alloc(INITIAL_PID_TABLE_SIZE
381 	    * sizeof(struct pid_table), KM_SLEEP);
382 	pid_tbl_mask = INITIAL_PID_TABLE_SIZE - 1;
383 	pid_max = PID_MAX;
384 
385 	/* Set free list running through table...
386 	   Preset 'use count' above PID_MAX so we allocate pid 1 next. */
387 	for (i = 0; i <= pid_tbl_mask; i++) {
388 		pid_table[i].pt_slot = PT_SET_FREE(LINK_EMPTY + i + 1);
389 		pid_table[i].pt_pgrp = 0;
390 		pid_table[i].pt_pid = 0;
391 	}
392 	/* slot 0 is just grabbed */
393 	next_free_pt = 1;
394 	/* Need to fix last entry. */
395 	last_free_pt = pid_tbl_mask;
396 	pid_table[last_free_pt].pt_slot = PT_SET_FREE(LINK_EMPTY);
397 	/* point at which we grow table - to avoid reusing pids too often */
398 	pid_alloc_lim = pid_tbl_mask - 1;
399 #undef LINK_EMPTY
400 
401 	/* Reserve PID 1 for init(8). */	/* XXX slightly gross */
402 	mutex_enter(&proc_lock);
403 	if (proc_alloc_pid_slot(&proc0, PT_SET_RESERVED) != 1)
404 		panic("failed to reserve PID 1 for init(8)");
405 	mutex_exit(&proc_lock);
406 
407 	proc_specificdata_domain = specificdata_domain_create();
408 	KASSERT(proc_specificdata_domain != NULL);
409 
410 	size_t proc_alignment = coherency_unit;
411 	if (proc_alignment < MIN_PROC_ALIGNMENT)
412 		proc_alignment = MIN_PROC_ALIGNMENT;
413 
414 	proc_cache = pool_cache_init(sizeof(struct proc), proc_alignment, 0, 0,
415 	    "procpl", NULL, IPL_NONE, proc_ctor, NULL, NULL);
416 
417 	proc_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS,
418 	    proc_listener_cb, NULL);
419 }
420 
421 void
422 procinit_sysctl(void)
423 {
424 	static struct sysctllog *clog;
425 
426 	sysctl_createv(&clog, 0, NULL, NULL,
427 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
428 		       CTLTYPE_INT, "expose_address",
429 		       SYSCTL_DESCR("Enable exposing kernel addresses"),
430 		       sysctl_security_expose_address, 0,
431 		       &kern_expose_address, 0, CTL_KERN, CTL_CREATE, CTL_EOL);
432 	sysctl_createv(&clog, 0, NULL, NULL,
433 		       CTLFLAG_PERMANENT,
434 		       CTLTYPE_NODE, "proc",
435 		       SYSCTL_DESCR("System-wide process information"),
436 		       sysctl_doeproc, 0, NULL, 0,
437 		       CTL_KERN, KERN_PROC, CTL_EOL);
438 	sysctl_createv(&clog, 0, NULL, NULL,
439 		       CTLFLAG_PERMANENT,
440 		       CTLTYPE_NODE, "proc2",
441 		       SYSCTL_DESCR("Machine-independent process information"),
442 		       sysctl_doeproc, 0, NULL, 0,
443 		       CTL_KERN, KERN_PROC2, CTL_EOL);
444 	sysctl_createv(&clog, 0, NULL, NULL,
445 		       CTLFLAG_PERMANENT,
446 		       CTLTYPE_NODE, "proc_args",
447 		       SYSCTL_DESCR("Process argument information"),
448 		       sysctl_kern_proc_args, 0, NULL, 0,
449 		       CTL_KERN, KERN_PROC_ARGS, CTL_EOL);
450 
451 	/*
452 	  "nodes" under these:
453 
454 	  KERN_PROC_ALL
455 	  KERN_PROC_PID pid
456 	  KERN_PROC_PGRP pgrp
457 	  KERN_PROC_SESSION sess
458 	  KERN_PROC_TTY tty
459 	  KERN_PROC_UID uid
460 	  KERN_PROC_RUID uid
461 	  KERN_PROC_GID gid
462 	  KERN_PROC_RGID gid
463 
464 	  all in all, probably not worth the effort...
465 	*/
466 }
467 
468 /*
469  * Initialize process 0.
470  */
471 void
472 proc0_init(void)
473 {
474 	struct proc *p;
475 	struct pgrp *pg;
476 	struct rlimit *rlim;
477 	rlim_t lim;
478 	int i;
479 
480 	p = &proc0;
481 	pg = &pgrp0;
482 
483 	mutex_init(&p->p_stmutex, MUTEX_DEFAULT, IPL_HIGH);
484 	mutex_init(&p->p_auxlock, MUTEX_DEFAULT, IPL_NONE);
485 	p->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
486 
487 	rw_init(&p->p_reflock);
488 	cv_init(&p->p_waitcv, "wait");
489 	cv_init(&p->p_lwpcv, "lwpwait");
490 
491 	LIST_INSERT_HEAD(&p->p_lwps, &lwp0, l_sibling);
492 
493 	KASSERT(lwp0.l_lid == 0);
494 	pid_table[lwp0.l_lid].pt_slot = PT_SET_LWP(&lwp0);
495 	LIST_INSERT_HEAD(&allproc, p, p_list);
496 
497 	pid_table[lwp0.l_lid].pt_pgrp = pg;
498 	LIST_INSERT_HEAD(&pg->pg_members, p, p_pglist);
499 
500 #ifdef __HAVE_SYSCALL_INTERN
501 	(*p->p_emul->e_syscall_intern)(p);
502 #endif
503 
504 	/* Create credentials. */
505 	cred0 = kauth_cred_alloc();
506 	p->p_cred = cred0;
507 
508 	/* Create the CWD info. */
509 	rw_init(&cwdi0.cwdi_lock);
510 
511 	/* Create the limits structures. */
512 	mutex_init(&limit0.pl_lock, MUTEX_DEFAULT, IPL_NONE);
513 
514 	rlim = limit0.pl_rlimit;
515 	for (i = 0; i < __arraycount(limit0.pl_rlimit); i++) {
516 		rlim[i].rlim_cur = RLIM_INFINITY;
517 		rlim[i].rlim_max = RLIM_INFINITY;
518 	}
519 
520 	rlim[RLIMIT_NOFILE].rlim_max = maxfiles;
521 	rlim[RLIMIT_NOFILE].rlim_cur = maxfiles < nofile ? maxfiles : nofile;
522 
523 	rlim[RLIMIT_NPROC].rlim_max = maxproc;
524 	rlim[RLIMIT_NPROC].rlim_cur = maxproc < maxuprc ? maxproc : maxuprc;
525 
526 	lim = MIN(VM_MAXUSER_ADDRESS, ctob((rlim_t)uvm_availmem(false)));
527 	rlim[RLIMIT_RSS].rlim_max = lim;
528 	rlim[RLIMIT_MEMLOCK].rlim_max = lim;
529 	rlim[RLIMIT_MEMLOCK].rlim_cur = lim / 3;
530 
531 	rlim[RLIMIT_NTHR].rlim_max = maxlwp;
532 	rlim[RLIMIT_NTHR].rlim_cur = maxlwp < maxuprc ? maxlwp : maxuprc;
533 
534 	/* Note that default core name has zero length. */
535 	limit0.pl_corename = defcorename;
536 	limit0.pl_cnlen = 0;
537 	limit0.pl_refcnt = 1;
538 	limit0.pl_writeable = false;
539 	limit0.pl_sv_limit = NULL;
540 
541 	/* Configure virtual memory system, set vm rlimits. */
542 	uvm_init_limits(p);
543 
544 	/* Initialize file descriptor table for proc0. */
545 	fd_init(&filedesc0);
546 
547 	/*
548 	 * Initialize proc0's vmspace, which uses the kernel pmap.
549 	 * All kernel processes (which never have user space mappings)
550 	 * share proc0's vmspace, and thus, the kernel pmap.
551 	 */
552 	uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
553 	    trunc_page(VM_MAXUSER_ADDRESS),
554 #ifdef __USE_TOPDOWN_VM
555 	    true
556 #else
557 	    false
558 #endif
559 	    );
560 
561 	/* Initialize signal state for proc0. XXX IPL_SCHED */
562 	mutex_init(&p->p_sigacts->sa_mutex, MUTEX_DEFAULT, IPL_SCHED);
563 	siginit(p);
564 
565 	proc_initspecific(p);
566 	kdtrace_proc_ctor(NULL, p);
567 }
568 
569 /*
570  * Session reference counting.
571  */
572 
573 void
574 proc_sesshold(struct session *ss)
575 {
576 
577 	KASSERT(mutex_owned(&proc_lock));
578 	ss->s_count++;
579 }
580 
581 void
582 proc_sessrele(struct session *ss)
583 {
584 	struct pgrp *pg;
585 
586 	KASSERT(mutex_owned(&proc_lock));
587 	KASSERT(ss->s_count > 0);
588 
589 	/*
590 	 * We keep the pgrp with the same id as the session in order to
591 	 * stop a process being given the same pid.  Since the pgrp holds
592 	 * a reference to the session, it must be a 'zombie' pgrp by now.
593 	 */
594 	if (--ss->s_count == 0) {
595 		pg = pg_remove(ss->s_sid);
596 	} else {
597 		pg = NULL;
598 		ss = NULL;
599 	}
600 
601 	mutex_exit(&proc_lock);
602 
603 	if (pg)
604 		kmem_free(pg, sizeof(struct pgrp));
605 	if (ss)
606 		kmem_free(ss, sizeof(struct session));
607 }
608 
609 /*
610  * Check that the specified process group is in the session of the
611  * specified process.
612  * Treats -ve ids as process ids.
613  * Used to validate TIOCSPGRP requests.
614  */
615 int
616 pgid_in_session(struct proc *p, pid_t pg_id)
617 {
618 	struct pgrp *pgrp;
619 	struct session *session;
620 	int error;
621 
622 	mutex_enter(&proc_lock);
623 	if (pg_id < 0) {
624 		struct proc *p1 = proc_find(-pg_id);
625 		if (p1 == NULL) {
626 			error = EINVAL;
627 			goto fail;
628 		}
629 		pgrp = p1->p_pgrp;
630 	} else {
631 		pgrp = pgrp_find(pg_id);
632 		if (pgrp == NULL) {
633 			error = EINVAL;
634 			goto fail;
635 		}
636 	}
637 	session = pgrp->pg_session;
638 	error = (session != p->p_pgrp->pg_session) ? EPERM : 0;
639 fail:
640 	mutex_exit(&proc_lock);
641 	return error;
642 }
643 
644 /*
645  * p_inferior: is p an inferior of q?
646  */
647 static inline bool
648 p_inferior(struct proc *p, struct proc *q)
649 {
650 
651 	KASSERT(mutex_owned(&proc_lock));
652 
653 	for (; p != q; p = p->p_pptr)
654 		if (p->p_pid == 0)
655 			return false;
656 	return true;
657 }
658 
659 /*
660  * proc_find_lwp: locate an lwp in said proc by the ID.
661  *
662  * => Must be called with p::p_lock held.
663  * => LSIDL lwps are not returned because they are only partially
664  *    constructed while occupying the slot.
665  * => Callers need to be careful about lwp::l_stat of the returned
666  *    lwp.
667  */
668 struct lwp *
669 proc_find_lwp(proc_t *p, pid_t pid)
670 {
671 	struct pid_table *pt;
672 	struct lwp *l = NULL;
673 	uintptr_t slot;
674 	int s;
675 
676 	KASSERT(mutex_owned(p->p_lock));
677 
678 	/*
679 	 * Look in the pid_table.  This is done unlocked inside a pserialize
680 	 * read section covering pid_table's memory allocation only, so take
681 	 * care to read the slot atomically and only once.  This issues a
682 	 * memory barrier for dependent loads on alpha.
683 	 */
684 	s = pserialize_read_enter();
685 	pt = &pid_table[pid & pid_tbl_mask];
686 	slot = atomic_load_consume(&pt->pt_slot);
687 	if (__predict_false(!PT_IS_LWP(slot))) {
688 		pserialize_read_exit(s);
689 		return NULL;
690 	}
691 
692 	/*
693 	 * Check to see if the LWP is from the correct process.  We won't
694 	 * see entries in pid_table from a prior process that also used "p",
695 	 * by virtue of the fact that allocating "p" means all prior updates
696 	 * to dependant data structures are visible to this thread.
697 	 */
698 	l = PT_GET_LWP(slot);
699 	if (__predict_false(atomic_load_relaxed(&l->l_proc) != p)) {
700 		pserialize_read_exit(s);
701 		return NULL;
702 	}
703 
704 	/*
705 	 * We now know that p->p_lock holds this LWP stable.
706 	 *
707 	 * If the status is not LSIDL, it means the LWP is intended to be
708 	 * findable by LID and l_lid cannot change behind us.
709 	 *
710 	 * No need to acquire the LWP's lock to check for LSIDL, as
711 	 * p->p_lock must be held to transition in and out of LSIDL.
712 	 * Any other observed state of is no particular interest.
713 	 */
714 	pserialize_read_exit(s);
715 	return l->l_stat != LSIDL && l->l_lid == pid ? l : NULL;
716 }
717 
718 /*
719  * proc_find_lwp_unlocked: locate an lwp in said proc by the ID.
720  *
721  * => Called in a pserialize read section with no locks held.
722  * => LSIDL lwps are not returned because they are only partially
723  *    constructed while occupying the slot.
724  * => Callers need to be careful about lwp::l_stat of the returned
725  *    lwp.
726  * => If an LWP is found, it's returned locked.
727  */
728 struct lwp *
729 proc_find_lwp_unlocked(proc_t *p, pid_t pid)
730 {
731 	struct pid_table *pt;
732 	struct lwp *l = NULL;
733 	uintptr_t slot;
734 
735 	KASSERT(pserialize_in_read_section());
736 
737 	/*
738 	 * Look in the pid_table.  This is done unlocked inside a pserialize
739 	 * read section covering pid_table's memory allocation only, so take
740 	 * care to read the slot atomically and only once.  This issues a
741 	 * memory barrier for dependent loads on alpha.
742 	 */
743 	pt = &pid_table[pid & pid_tbl_mask];
744 	slot = atomic_load_consume(&pt->pt_slot);
745 	if (__predict_false(!PT_IS_LWP(slot))) {
746 		return NULL;
747 	}
748 
749 	/*
750 	 * Lock the LWP we found to get it stable.  If it's embryonic or
751 	 * reaped (LSIDL) then none of the other fields can safely be
752 	 * checked.
753 	 */
754 	l = PT_GET_LWP(slot);
755 	lwp_lock(l);
756 	if (__predict_false(l->l_stat == LSIDL)) {
757 		lwp_unlock(l);
758 		return NULL;
759 	}
760 
761 	/*
762 	 * l_proc and l_lid are now known stable because the LWP is not
763 	 * LSIDL, so check those fields too to make sure we found the
764 	 * right thing.
765 	 */
766 	if (__predict_false(l->l_proc != p || l->l_lid != pid)) {
767 		lwp_unlock(l);
768 		return NULL;
769 	}
770 
771 	/* Everything checks out, return it locked. */
772 	return l;
773 }
774 
775 /*
776  * proc_find_lwp_acquire_proc: locate an lwp and acquire a lock
777  * on its containing proc.
778  *
779  * => Similar to proc_find_lwp(), but does not require you to have
780  *    the proc a priori.
781  * => Also returns proc * to caller, with p::p_lock held.
782  * => Same caveats apply.
783  */
784 struct lwp *
785 proc_find_lwp_acquire_proc(pid_t pid, struct proc **pp)
786 {
787 	struct pid_table *pt;
788 	struct proc *p = NULL;
789 	struct lwp *l = NULL;
790 	uintptr_t slot;
791 
792 	KASSERT(pp != NULL);
793 	mutex_enter(&proc_lock);
794 	pt = &pid_table[pid & pid_tbl_mask];
795 
796 	slot = pt->pt_slot;
797 	if (__predict_true(PT_IS_LWP(slot) && pt->pt_pid == pid)) {
798 		l = PT_GET_LWP(slot);
799 		p = l->l_proc;
800 		mutex_enter(p->p_lock);
801 		if (__predict_false(l->l_stat == LSIDL)) {
802 			mutex_exit(p->p_lock);
803 			l = NULL;
804 			p = NULL;
805 		}
806 	}
807 	mutex_exit(&proc_lock);
808 
809 	KASSERT(p == NULL || mutex_owned(p->p_lock));
810 	*pp = p;
811 	return l;
812 }
813 
814 /*
815  * proc_find_raw_pid_table_locked: locate a process by the ID.
816  *
817  * => Must be called with proc_lock held.
818  */
819 static proc_t *
820 proc_find_raw_pid_table_locked(pid_t pid, bool any_lwpid)
821 {
822 	struct pid_table *pt;
823 	proc_t *p = NULL;
824 	uintptr_t slot;
825 
826 	/* No - used by DDB.  KASSERT(mutex_owned(&proc_lock)); */
827 	pt = &pid_table[pid & pid_tbl_mask];
828 
829 	slot = pt->pt_slot;
830 	if (__predict_true(PT_IS_LWP(slot) && pt->pt_pid == pid)) {
831 		/*
832 		 * When looking up processes, require a direct match
833 		 * on the PID assigned to the proc, not just one of
834 		 * its LWPs.
835 		 *
836 		 * N.B. We require lwp::l_proc of LSIDL LWPs to be
837 		 * valid here.
838 		 */
839 		p = PT_GET_LWP(slot)->l_proc;
840 		if (__predict_false(p->p_pid != pid && !any_lwpid))
841 			p = NULL;
842 	} else if (PT_IS_PROC(slot) && pt->pt_pid == pid) {
843 		p = PT_GET_PROC(slot);
844 	}
845 	return p;
846 }
847 
848 proc_t *
849 proc_find_raw(pid_t pid)
850 {
851 
852 	return proc_find_raw_pid_table_locked(pid, false);
853 }
854 
855 static proc_t *
856 proc_find_internal(pid_t pid, bool any_lwpid)
857 {
858 	proc_t *p;
859 
860 	KASSERT(mutex_owned(&proc_lock));
861 
862 	p = proc_find_raw_pid_table_locked(pid, any_lwpid);
863 	if (__predict_false(p == NULL)) {
864 		return NULL;
865 	}
866 
867 	/*
868 	 * Only allow live processes to be found by PID.
869 	 * XXX: p_stat might change, since proc unlocked.
870 	 */
871 	if (__predict_true(p->p_stat == SACTIVE || p->p_stat == SSTOP)) {
872 		return p;
873 	}
874 	return NULL;
875 }
876 
877 proc_t *
878 proc_find(pid_t pid)
879 {
880 	return proc_find_internal(pid, false);
881 }
882 
883 proc_t *
884 proc_find_lwpid(pid_t pid)
885 {
886 	return proc_find_internal(pid, true);
887 }
888 
889 /*
890  * pgrp_find: locate a process group by the ID.
891  *
892  * => Must be called with proc_lock held.
893  */
894 struct pgrp *
895 pgrp_find(pid_t pgid)
896 {
897 	struct pgrp *pg;
898 
899 	KASSERT(mutex_owned(&proc_lock));
900 
901 	pg = pid_table[pgid & pid_tbl_mask].pt_pgrp;
902 
903 	/*
904 	 * Cannot look up a process group that only exists because the
905 	 * session has not died yet (traditional).
906 	 */
907 	if (pg == NULL || pg->pg_id != pgid || LIST_EMPTY(&pg->pg_members)) {
908 		return NULL;
909 	}
910 	return pg;
911 }
912 
913 static void
914 expand_pid_table(void)
915 {
916 	size_t pt_size, tsz;
917 	struct pid_table *n_pt, *new_pt;
918 	uintptr_t slot;
919 	struct pgrp *pgrp;
920 	pid_t pid, rpid;
921 	u_int i;
922 	uint new_pt_mask;
923 
924 	KASSERT(mutex_owned(&proc_lock));
925 
926 	/* Unlock the pid_table briefly to allocate memory. */
927 	pt_size = pid_tbl_mask + 1;
928 	mutex_exit(&proc_lock);
929 
930 	tsz = pt_size * 2 * sizeof(struct pid_table);
931 	new_pt = kmem_alloc(tsz, KM_SLEEP);
932 	new_pt_mask = pt_size * 2 - 1;
933 
934 	/* XXX For now.  The pratical limit is much lower anyway. */
935 	KASSERT(new_pt_mask <= FUTEX_TID_MASK);
936 
937 	mutex_enter(&proc_lock);
938 	if (pt_size != pid_tbl_mask + 1) {
939 		/* Another process beat us to it... */
940 		mutex_exit(&proc_lock);
941 		kmem_free(new_pt, tsz);
942 		goto out;
943 	}
944 
945 	/*
946 	 * Copy entries from old table into new one.
947 	 * If 'pid' is 'odd' we need to place in the upper half,
948 	 * even pid's to the lower half.
949 	 * Free items stay in the low half so we don't have to
950 	 * fixup the reference to them.
951 	 * We stuff free items on the front of the freelist
952 	 * because we can't write to unmodified entries.
953 	 * Processing the table backwards maintains a semblance
954 	 * of issuing pid numbers that increase with time.
955 	 */
956 	i = pt_size - 1;
957 	n_pt = new_pt + i;
958 	for (; ; i--, n_pt--) {
959 		slot = pid_table[i].pt_slot;
960 		pgrp = pid_table[i].pt_pgrp;
961 		if (!PT_VALID(slot)) {
962 			/* Up 'use count' so that link is valid */
963 			pid = (PT_NEXT(slot) + pt_size) & ~pt_size;
964 			rpid = 0;
965 			slot = PT_SET_FREE(pid);
966 			if (pgrp)
967 				pid = pgrp->pg_id;
968 		} else {
969 			pid = pid_table[i].pt_pid;
970 			rpid = pid;
971 		}
972 
973 		/* Save entry in appropriate half of table */
974 		n_pt[pid & pt_size].pt_slot = slot;
975 		n_pt[pid & pt_size].pt_pgrp = pgrp;
976 		n_pt[pid & pt_size].pt_pid = rpid;
977 
978 		/* Put other piece on start of free list */
979 		pid = (pid ^ pt_size) & ~pid_tbl_mask;
980 		n_pt[pid & pt_size].pt_slot =
981 			PT_SET_FREE((pid & ~pt_size) | next_free_pt);
982 		n_pt[pid & pt_size].pt_pgrp = 0;
983 		n_pt[pid & pt_size].pt_pid = 0;
984 
985 		next_free_pt = i | (pid & pt_size);
986 		if (i == 0)
987 			break;
988 	}
989 
990 	/* Save old table size and switch tables */
991 	tsz = pt_size * sizeof(struct pid_table);
992 	n_pt = pid_table;
993 	pid_table = new_pt;
994 	pid_tbl_mask = new_pt_mask;
995 
996 	/*
997 	 * pid_max starts as PID_MAX (= 30000), once we have 16384
998 	 * allocated pids we need it to be larger!
999 	 */
1000 	if (pid_tbl_mask > PID_MAX) {
1001 		pid_max = pid_tbl_mask * 2 + 1;
1002 		pid_alloc_lim |= pid_alloc_lim << 1;
1003 	} else
1004 		pid_alloc_lim <<= 1;	/* doubles number of free slots... */
1005 
1006 	mutex_exit(&proc_lock);
1007 
1008 	/*
1009 	 * Make sure that unlocked access to the old pid_table is complete
1010 	 * and then free it.
1011 	 */
1012 	pserialize_perform(proc_psz);
1013 	kmem_free(n_pt, tsz);
1014 
1015  out:	/* Return with proc_lock held again. */
1016 	mutex_enter(&proc_lock);
1017 }
1018 
1019 struct proc *
1020 proc_alloc(void)
1021 {
1022 	struct proc *p;
1023 
1024 	p = pool_cache_get(proc_cache, PR_WAITOK);
1025 	p->p_stat = SIDL;			/* protect against others */
1026 	proc_initspecific(p);
1027 	kdtrace_proc_ctor(NULL, p);
1028 
1029 	/*
1030 	 * Allocate a placeholder in the pid_table.  When we create the
1031 	 * first LWP for this process, it will take ownership of the
1032 	 * slot.
1033 	 */
1034 	if (__predict_false(proc_alloc_pid(p) == -1)) {
1035 		/* Allocating the PID failed; unwind. */
1036 		proc_finispecific(p);
1037 		proc_free_mem(p);
1038 		p = NULL;
1039 	}
1040 	return p;
1041 }
1042 
1043 /*
1044  * proc_alloc_pid_slot: allocate PID and record the occcupant so that
1045  * proc_find_raw() can find it by the PID.
1046  */
1047 static pid_t __noinline
1048 proc_alloc_pid_slot(struct proc *p, uintptr_t slot)
1049 {
1050 	struct pid_table *pt;
1051 	pid_t pid;
1052 	int nxt;
1053 
1054 	KASSERT(mutex_owned(&proc_lock));
1055 
1056 	for (;;expand_pid_table()) {
1057 		if (__predict_false(pid_alloc_cnt >= pid_alloc_lim)) {
1058 			/* ensure pids cycle through 2000+ values */
1059 			continue;
1060 		}
1061 		/*
1062 		 * The first user process *must* be given PID 1.
1063 		 * it has already been reserved for us.  This
1064 		 * will be coming in from the proc_alloc() call
1065 		 * above, and the entry will be usurped later when
1066 		 * the first user LWP is created.
1067 		 * XXX this is slightly gross.
1068 		 */
1069 		if (__predict_false(PT_RESERVED(pid_table[1].pt_slot) &&
1070 				    p != &proc0)) {
1071 			KASSERT(PT_IS_PROC(slot));
1072 			pt = &pid_table[1];
1073 			pt->pt_slot = slot;
1074 			return 1;
1075 		}
1076 		pt = &pid_table[next_free_pt];
1077 #ifdef DIAGNOSTIC
1078 		if (__predict_false(PT_VALID(pt->pt_slot) || pt->pt_pgrp))
1079 			panic("proc_alloc: slot busy");
1080 #endif
1081 		nxt = PT_NEXT(pt->pt_slot);
1082 		if (nxt & pid_tbl_mask)
1083 			break;
1084 		/* Table full - expand (NB last entry not used....) */
1085 	}
1086 
1087 	/* pid is 'saved use count' + 'size' + entry */
1088 	pid = (nxt & ~pid_tbl_mask) + pid_tbl_mask + 1 + next_free_pt;
1089 	if ((uint)pid > (uint)pid_max)
1090 		pid &= pid_tbl_mask;
1091 	next_free_pt = nxt & pid_tbl_mask;
1092 
1093 	/* XXX For now.  The pratical limit is much lower anyway. */
1094 	KASSERT(pid <= FUTEX_TID_MASK);
1095 
1096 	/* Grab table slot */
1097 	pt->pt_slot = slot;
1098 
1099 	KASSERT(pt->pt_pid == 0);
1100 	pt->pt_pid = pid;
1101 	pid_alloc_cnt++;
1102 
1103 	return pid;
1104 }
1105 
1106 pid_t
1107 proc_alloc_pid(struct proc *p)
1108 {
1109 	pid_t pid;
1110 
1111 	KASSERT((((uintptr_t)p) & PT_F_ALLBITS) == 0);
1112 	KASSERT(p->p_stat == SIDL);
1113 
1114 	mutex_enter(&proc_lock);
1115 	pid = proc_alloc_pid_slot(p, PT_SET_PROC(p));
1116 	if (pid != -1)
1117 		p->p_pid = pid;
1118 	mutex_exit(&proc_lock);
1119 
1120 	return pid;
1121 }
1122 
1123 pid_t
1124 proc_alloc_lwpid(struct proc *p, struct lwp *l)
1125 {
1126 	struct pid_table *pt;
1127 	pid_t pid;
1128 
1129 	KASSERT((((uintptr_t)l) & PT_F_ALLBITS) == 0);
1130 	KASSERT(l->l_proc == p);
1131 	KASSERT(l->l_stat == LSIDL);
1132 
1133 	/*
1134 	 * For unlocked lookup in proc_find_lwp(), make sure l->l_proc
1135 	 * is globally visible before the LWP becomes visible via the
1136 	 * pid_table.
1137 	 */
1138 #ifndef __HAVE_ATOMIC_AS_MEMBAR
1139 	membar_producer();
1140 #endif
1141 
1142 	/*
1143 	 * If the slot for p->p_pid currently points to the proc,
1144 	 * then we should usurp this ID for the LWP.  This happens
1145 	 * at least once per process (for the first LWP), and can
1146 	 * happen again if the first LWP for a process exits and
1147 	 * before the process creates another.
1148 	 */
1149 	mutex_enter(&proc_lock);
1150 	pid = p->p_pid;
1151 	pt = &pid_table[pid & pid_tbl_mask];
1152 	KASSERT(pt->pt_pid == pid);
1153 	if (PT_IS_PROC(pt->pt_slot)) {
1154 		KASSERT(PT_GET_PROC(pt->pt_slot) == p);
1155 		l->l_lid = pid;
1156 		pt->pt_slot = PT_SET_LWP(l);
1157 	} else {
1158 		/* Need to allocate a new slot. */
1159 		pid = proc_alloc_pid_slot(p, PT_SET_LWP(l));
1160 		if (pid != -1)
1161 			l->l_lid = pid;
1162 	}
1163 	mutex_exit(&proc_lock);
1164 
1165 	return pid;
1166 }
1167 
1168 static void __noinline
1169 proc_free_pid_internal(pid_t pid, uintptr_t type __diagused)
1170 {
1171 	struct pid_table *pt;
1172 
1173 	pt = &pid_table[pid & pid_tbl_mask];
1174 
1175 	KASSERT(PT_GET_TYPE(pt->pt_slot) == type);
1176 	KASSERT(pt->pt_pid == pid);
1177 
1178 	/* save pid use count in slot */
1179 	pt->pt_slot = PT_SET_FREE(pid & ~pid_tbl_mask);
1180 	pt->pt_pid = 0;
1181 
1182 	if (pt->pt_pgrp == NULL) {
1183 		/* link last freed entry onto ours */
1184 		pid &= pid_tbl_mask;
1185 		pt = &pid_table[last_free_pt];
1186 		pt->pt_slot = PT_SET_FREE(PT_NEXT(pt->pt_slot) | pid);
1187 		pt->pt_pid = 0;
1188 		last_free_pt = pid;
1189 		pid_alloc_cnt--;
1190 	}
1191 }
1192 
1193 /*
1194  * Free a process id - called from proc_free (in kern_exit.c)
1195  *
1196  * Called with the proc_lock held.
1197  */
1198 void
1199 proc_free_pid(pid_t pid)
1200 {
1201 
1202 	KASSERT(mutex_owned(&proc_lock));
1203 	proc_free_pid_internal(pid, PT_F_PROC);
1204 }
1205 
1206 /*
1207  * Free a process id used by an LWP.  If this was the process's
1208  * first LWP, we convert the slot to point to the process; the
1209  * entry will get cleaned up later when the process finishes exiting.
1210  *
1211  * If not, then it's the same as proc_free_pid().
1212  */
1213 void
1214 proc_free_lwpid(struct proc *p, pid_t pid)
1215 {
1216 
1217 	KASSERT(mutex_owned(&proc_lock));
1218 
1219 	if (__predict_true(p->p_pid == pid)) {
1220 		struct pid_table *pt;
1221 
1222 		pt = &pid_table[pid & pid_tbl_mask];
1223 
1224 		KASSERT(pt->pt_pid == pid);
1225 		KASSERT(PT_IS_LWP(pt->pt_slot));
1226 		KASSERT(PT_GET_LWP(pt->pt_slot)->l_proc == p);
1227 
1228 		pt->pt_slot = PT_SET_PROC(p);
1229 		return;
1230 	}
1231 	proc_free_pid_internal(pid, PT_F_LWP);
1232 }
1233 
1234 void
1235 proc_free_mem(struct proc *p)
1236 {
1237 
1238 	kdtrace_proc_dtor(NULL, p);
1239 	pool_cache_put(proc_cache, p);
1240 }
1241 
1242 /*
1243  * proc_enterpgrp: move p to a new or existing process group (and session).
1244  *
1245  * If we are creating a new pgrp, the pgid should equal
1246  * the calling process' pid.
1247  * If is only valid to enter a process group that is in the session
1248  * of the process.
1249  * Also mksess should only be set if we are creating a process group
1250  *
1251  * Only called from sys_setsid, sys_setpgid and posix_spawn/spawn_return.
1252  */
1253 int
1254 proc_enterpgrp(struct proc *curp, pid_t pid, pid_t pgid, bool mksess)
1255 {
1256 	struct pgrp *new_pgrp, *pgrp;
1257 	struct session *sess;
1258 	struct proc *p;
1259 	int rval;
1260 	pid_t pg_id = NO_PGID;
1261 
1262 	/* Allocate data areas we might need before doing any validity checks */
1263 	sess = mksess ? kmem_alloc(sizeof(*sess), KM_SLEEP) : NULL;
1264 	new_pgrp = kmem_alloc(sizeof(*new_pgrp), KM_SLEEP);
1265 
1266 	mutex_enter(&proc_lock);
1267 	rval = EPERM;	/* most common error (to save typing) */
1268 
1269 	/* Check pgrp exists or can be created */
1270 	pgrp = pid_table[pgid & pid_tbl_mask].pt_pgrp;
1271 	if (pgrp != NULL && pgrp->pg_id != pgid)
1272 		goto done;
1273 
1274 	/* Can only set another process under restricted circumstances. */
1275 	if (pid != curp->p_pid) {
1276 		/* Must exist and be one of our children... */
1277 		p = proc_find_internal(pid, false);
1278 		if (p == NULL || !p_inferior(p, curp)) {
1279 			rval = ESRCH;
1280 			goto done;
1281 		}
1282 		/* ... in the same session... */
1283 		if (sess != NULL || p->p_session != curp->p_session)
1284 			goto done;
1285 		/* ... existing pgid must be in same session ... */
1286 		if (pgrp != NULL && pgrp->pg_session != p->p_session)
1287 			goto done;
1288 		/* ... and not done an exec. */
1289 		if (p->p_flag & PK_EXEC) {
1290 			rval = EACCES;
1291 			goto done;
1292 		}
1293 	} else {
1294 		/* ... setsid() cannot re-enter a pgrp */
1295 		if (mksess && (curp->p_pgid == curp->p_pid ||
1296 		    pgrp_find(curp->p_pid)))
1297 			goto done;
1298 		p = curp;
1299 	}
1300 
1301 	/* Changing the process group/session of a session
1302 	   leader is definitely off limits. */
1303 	if (SESS_LEADER(p)) {
1304 		if (sess == NULL && p->p_pgrp == pgrp)
1305 			/* unless it's a definite noop */
1306 			rval = 0;
1307 		goto done;
1308 	}
1309 
1310 	/* Can only create a process group with id of process */
1311 	if (pgrp == NULL && pgid != pid)
1312 		goto done;
1313 
1314 	/* Can only create a session if creating pgrp */
1315 	if (sess != NULL && pgrp != NULL)
1316 		goto done;
1317 
1318 	/* Check we allocated memory for a pgrp... */
1319 	if (pgrp == NULL && new_pgrp == NULL)
1320 		goto done;
1321 
1322 	/* Don't attach to 'zombie' pgrp */
1323 	if (pgrp != NULL && LIST_EMPTY(&pgrp->pg_members))
1324 		goto done;
1325 
1326 	/* Expect to succeed now */
1327 	rval = 0;
1328 
1329 	if (pgrp == p->p_pgrp)
1330 		/* nothing to do */
1331 		goto done;
1332 
1333 	/* Ok all setup, link up required structures */
1334 
1335 	if (pgrp == NULL) {
1336 		pgrp = new_pgrp;
1337 		new_pgrp = NULL;
1338 		if (sess != NULL) {
1339 			sess->s_sid = p->p_pid;
1340 			sess->s_leader = p;
1341 			sess->s_count = 1;
1342 			sess->s_ttyvp = NULL;
1343 			sess->s_ttyp = NULL;
1344 			sess->s_flags = p->p_session->s_flags & ~S_LOGIN_SET;
1345 			memcpy(sess->s_login, p->p_session->s_login,
1346 			    sizeof(sess->s_login));
1347 			p->p_lflag &= ~PL_CONTROLT;
1348 		} else {
1349 			sess = p->p_pgrp->pg_session;
1350 			proc_sesshold(sess);
1351 		}
1352 		pgrp->pg_session = sess;
1353 		sess = NULL;
1354 
1355 		pgrp->pg_id = pgid;
1356 		LIST_INIT(&pgrp->pg_members);
1357 #ifdef DIAGNOSTIC
1358 		if (__predict_false(pid_table[pgid & pid_tbl_mask].pt_pgrp))
1359 			panic("enterpgrp: pgrp table slot in use");
1360 		if (__predict_false(mksess && p != curp))
1361 			panic("enterpgrp: mksession and p != curproc");
1362 #endif
1363 		pid_table[pgid & pid_tbl_mask].pt_pgrp = pgrp;
1364 		pgrp->pg_jobc = 0;
1365 	}
1366 
1367 	/*
1368 	 * Adjust eligibility of affected pgrps to participate in job control.
1369 	 * Increment eligibility counts before decrementing, otherwise we
1370 	 * could reach 0 spuriously during the first call.
1371 	 */
1372 	fixjobc(p, pgrp, 1);
1373 	fixjobc(p, p->p_pgrp, 0);
1374 
1375 	/* Interlock with ttread(). */
1376 	mutex_spin_enter(&tty_lock);
1377 
1378 	/* Move process to requested group. */
1379 	LIST_REMOVE(p, p_pglist);
1380 	if (LIST_EMPTY(&p->p_pgrp->pg_members))
1381 		/* defer delete until we've dumped the lock */
1382 		pg_id = p->p_pgrp->pg_id;
1383 	p->p_pgrp = pgrp;
1384 	LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist);
1385 
1386 	/* Done with the swap; we can release the tty mutex. */
1387 	mutex_spin_exit(&tty_lock);
1388 
1389     done:
1390 	if (pg_id != NO_PGID) {
1391 		/* Releases proc_lock. */
1392 		pg_delete(pg_id);
1393 	} else {
1394 		mutex_exit(&proc_lock);
1395 	}
1396 	if (sess != NULL)
1397 		kmem_free(sess, sizeof(*sess));
1398 	if (new_pgrp != NULL)
1399 		kmem_free(new_pgrp, sizeof(*new_pgrp));
1400 #ifdef DEBUG_PGRP
1401 	if (__predict_false(rval))
1402 		printf("enterpgrp(%d,%d,%d), curproc %d, rval %d\n",
1403 			pid, pgid, mksess, curp->p_pid, rval);
1404 #endif
1405 	return rval;
1406 }
1407 
1408 /*
1409  * proc_leavepgrp: remove a process from its process group.
1410  *  => must be called with the proc_lock held, which will be released;
1411  */
1412 void
1413 proc_leavepgrp(struct proc *p)
1414 {
1415 	struct pgrp *pgrp;
1416 
1417 	KASSERT(mutex_owned(&proc_lock));
1418 
1419 	/* Interlock with ttread() */
1420 	mutex_spin_enter(&tty_lock);
1421 	pgrp = p->p_pgrp;
1422 	LIST_REMOVE(p, p_pglist);
1423 	p->p_pgrp = NULL;
1424 	mutex_spin_exit(&tty_lock);
1425 
1426 	if (LIST_EMPTY(&pgrp->pg_members)) {
1427 		/* Releases proc_lock. */
1428 		pg_delete(pgrp->pg_id);
1429 	} else {
1430 		mutex_exit(&proc_lock);
1431 	}
1432 }
1433 
1434 /*
1435  * pg_remove: remove a process group from the table.
1436  *  => must be called with the proc_lock held;
1437  *  => returns process group to free;
1438  */
1439 static struct pgrp *
1440 pg_remove(pid_t pg_id)
1441 {
1442 	struct pgrp *pgrp;
1443 	struct pid_table *pt;
1444 
1445 	KASSERT(mutex_owned(&proc_lock));
1446 
1447 	pt = &pid_table[pg_id & pid_tbl_mask];
1448 	pgrp = pt->pt_pgrp;
1449 
1450 	KASSERT(pgrp != NULL);
1451 	KASSERT(pgrp->pg_id == pg_id);
1452 	KASSERT(LIST_EMPTY(&pgrp->pg_members));
1453 
1454 	pt->pt_pgrp = NULL;
1455 
1456 	if (!PT_VALID(pt->pt_slot)) {
1457 		/* Orphaned pgrp, put slot onto free list. */
1458 		KASSERT((PT_NEXT(pt->pt_slot) & pid_tbl_mask) == 0);
1459 		pg_id &= pid_tbl_mask;
1460 		pt = &pid_table[last_free_pt];
1461 		pt->pt_slot = PT_SET_FREE(PT_NEXT(pt->pt_slot) | pg_id);
1462 		KASSERT(pt->pt_pid == 0);
1463 		last_free_pt = pg_id;
1464 		pid_alloc_cnt--;
1465 	}
1466 	return pgrp;
1467 }
1468 
1469 /*
1470  * pg_delete: delete and free a process group.
1471  *  => must be called with the proc_lock held, which will be released.
1472  */
1473 static void
1474 pg_delete(pid_t pg_id)
1475 {
1476 	struct pgrp *pg;
1477 	struct tty *ttyp;
1478 	struct session *ss;
1479 
1480 	KASSERT(mutex_owned(&proc_lock));
1481 
1482 	pg = pid_table[pg_id & pid_tbl_mask].pt_pgrp;
1483 	if (pg == NULL || pg->pg_id != pg_id || !LIST_EMPTY(&pg->pg_members)) {
1484 		mutex_exit(&proc_lock);
1485 		return;
1486 	}
1487 
1488 	ss = pg->pg_session;
1489 
1490 	/* Remove reference (if any) from tty to this process group */
1491 	mutex_spin_enter(&tty_lock);
1492 	ttyp = ss->s_ttyp;
1493 	if (ttyp != NULL && ttyp->t_pgrp == pg) {
1494 		ttyp->t_pgrp = NULL;
1495 		KASSERT(ttyp->t_session == ss);
1496 	}
1497 	mutex_spin_exit(&tty_lock);
1498 
1499 	/*
1500 	 * The leading process group in a session is freed by proc_sessrele(),
1501 	 * if last reference.  It will also release the locks.
1502 	 */
1503 	pg = (ss->s_sid != pg->pg_id) ? pg_remove(pg_id) : NULL;
1504 	proc_sessrele(ss);
1505 
1506 	if (pg != NULL) {
1507 		/* Free it, if was not done above. */
1508 		kmem_free(pg, sizeof(struct pgrp));
1509 	}
1510 }
1511 
1512 /*
1513  * Adjust pgrp jobc counters when specified process changes process group.
1514  * We count the number of processes in each process group that "qualify"
1515  * the group for terminal job control (those with a parent in a different
1516  * process group of the same session).  If that count reaches zero, the
1517  * process group becomes orphaned.  Check both the specified process'
1518  * process group and that of its children.
1519  * entering == 0 => p is leaving specified group.
1520  * entering == 1 => p is entering specified group.
1521  *
1522  * Call with proc_lock held.
1523  */
1524 void
1525 fixjobc(struct proc *p, struct pgrp *pgrp, int entering)
1526 {
1527 	struct pgrp *hispgrp;
1528 	struct session *mysession = pgrp->pg_session;
1529 	struct proc *child;
1530 
1531 	KASSERT(mutex_owned(&proc_lock));
1532 
1533 	/*
1534 	 * Check p's parent to see whether p qualifies its own process
1535 	 * group; if so, adjust count for p's process group.
1536 	 */
1537 	hispgrp = p->p_pptr->p_pgrp;
1538 	if (hispgrp != pgrp && hispgrp->pg_session == mysession) {
1539 		if (entering) {
1540 			pgrp->pg_jobc++;
1541 			p->p_lflag &= ~PL_ORPHANPG;
1542 		} else {
1543 			KASSERT(pgrp->pg_jobc > 0);
1544 			if (--pgrp->pg_jobc == 0)
1545 				orphanpg(pgrp);
1546 		}
1547 	}
1548 
1549 	/*
1550 	 * Check this process' children to see whether they qualify
1551 	 * their process groups; if so, adjust counts for children's
1552 	 * process groups.
1553 	 */
1554 	LIST_FOREACH(child, &p->p_children, p_sibling) {
1555 		hispgrp = child->p_pgrp;
1556 		if (hispgrp != pgrp && hispgrp->pg_session == mysession &&
1557 		    !P_ZOMBIE(child)) {
1558 			if (entering) {
1559 				child->p_lflag &= ~PL_ORPHANPG;
1560 				hispgrp->pg_jobc++;
1561 			} else {
1562 				KASSERT(hispgrp->pg_jobc > 0);
1563 				if (--hispgrp->pg_jobc == 0)
1564 					orphanpg(hispgrp);
1565 			}
1566 		}
1567 	}
1568 }
1569 
1570 /*
1571  * A process group has become orphaned;
1572  * if there are any stopped processes in the group,
1573  * hang-up all process in that group.
1574  *
1575  * Call with proc_lock held.
1576  */
1577 static void
1578 orphanpg(struct pgrp *pg)
1579 {
1580 	struct proc *p;
1581 
1582 	KASSERT(mutex_owned(&proc_lock));
1583 
1584 	LIST_FOREACH(p, &pg->pg_members, p_pglist) {
1585 		if (p->p_stat == SSTOP) {
1586 			p->p_lflag |= PL_ORPHANPG;
1587 			psignal(p, SIGHUP);
1588 			psignal(p, SIGCONT);
1589 		}
1590 	}
1591 }
1592 
1593 #ifdef DDB
1594 #include <ddb/db_output.h>
1595 void pidtbl_dump(void);
1596 void
1597 pidtbl_dump(void)
1598 {
1599 	struct pid_table *pt;
1600 	struct proc *p;
1601 	struct pgrp *pgrp;
1602 	uintptr_t slot;
1603 	int id;
1604 
1605 	db_printf("pid table %p size %x, next %x, last %x\n",
1606 		pid_table, pid_tbl_mask+1,
1607 		next_free_pt, last_free_pt);
1608 	for (pt = pid_table, id = 0; id <= pid_tbl_mask; id++, pt++) {
1609 		slot = pt->pt_slot;
1610 		if (!PT_VALID(slot) && !pt->pt_pgrp)
1611 			continue;
1612 		if (PT_IS_LWP(slot)) {
1613 			p = PT_GET_LWP(slot)->l_proc;
1614 		} else if (PT_IS_PROC(slot)) {
1615 			p = PT_GET_PROC(slot);
1616 		} else {
1617 			p = NULL;
1618 		}
1619 		db_printf("  id %x: ", id);
1620 		if (p != NULL)
1621 			db_printf("slotpid %d proc %p id %d (0x%x) %s\n",
1622 				pt->pt_pid, p, p->p_pid, p->p_pid, p->p_comm);
1623 		else
1624 			db_printf("next %x use %x\n",
1625 				PT_NEXT(slot) & pid_tbl_mask,
1626 				PT_NEXT(slot) & ~pid_tbl_mask);
1627 		if ((pgrp = pt->pt_pgrp)) {
1628 			db_printf("\tsession %p, sid %d, count %d, login %s\n",
1629 			    pgrp->pg_session, pgrp->pg_session->s_sid,
1630 			    pgrp->pg_session->s_count,
1631 			    pgrp->pg_session->s_login);
1632 			db_printf("\tpgrp %p, pg_id %d, pg_jobc %d, members %p\n",
1633 			    pgrp, pgrp->pg_id, pgrp->pg_jobc,
1634 			    LIST_FIRST(&pgrp->pg_members));
1635 			LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1636 				db_printf("\t\tpid %d addr %p pgrp %p %s\n",
1637 				    p->p_pid, p, p->p_pgrp, p->p_comm);
1638 			}
1639 		}
1640 	}
1641 }
1642 #endif /* DDB */
1643 
1644 #ifdef KSTACK_CHECK_MAGIC
1645 
1646 #define	KSTACK_MAGIC	0xdeadbeaf
1647 
1648 /* XXX should be per process basis? */
1649 static int	kstackleftmin = KSTACK_SIZE;
1650 static int	kstackleftthres = KSTACK_SIZE / 8;
1651 
1652 void
1653 kstack_setup_magic(const struct lwp *l)
1654 {
1655 	uint32_t *ip;
1656 	uint32_t const *end;
1657 
1658 	KASSERT(l != NULL);
1659 	KASSERT(l != &lwp0);
1660 
1661 	/*
1662 	 * fill all the stack with magic number
1663 	 * so that later modification on it can be detected.
1664 	 */
1665 	ip = (uint32_t *)KSTACK_LOWEST_ADDR(l);
1666 	end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
1667 	for (; ip < end; ip++) {
1668 		*ip = KSTACK_MAGIC;
1669 	}
1670 }
1671 
1672 void
1673 kstack_check_magic(const struct lwp *l)
1674 {
1675 	uint32_t const *ip, *end;
1676 	int stackleft;
1677 
1678 	KASSERT(l != NULL);
1679 
1680 	/* don't check proc0 */ /*XXX*/
1681 	if (l == &lwp0)
1682 		return;
1683 
1684 #ifdef __MACHINE_STACK_GROWS_UP
1685 	/* stack grows upwards (eg. hppa) */
1686 	ip = (uint32_t *)((void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
1687 	end = (uint32_t *)KSTACK_LOWEST_ADDR(l);
1688 	for (ip--; ip >= end; ip--)
1689 		if (*ip != KSTACK_MAGIC)
1690 			break;
1691 
1692 	stackleft = (void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE - (void *)ip;
1693 #else /* __MACHINE_STACK_GROWS_UP */
1694 	/* stack grows downwards (eg. i386) */
1695 	ip = (uint32_t *)KSTACK_LOWEST_ADDR(l);
1696 	end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
1697 	for (; ip < end; ip++)
1698 		if (*ip != KSTACK_MAGIC)
1699 			break;
1700 
1701 	stackleft = ((const char *)ip) - (const char *)KSTACK_LOWEST_ADDR(l);
1702 #endif /* __MACHINE_STACK_GROWS_UP */
1703 
1704 	if (kstackleftmin > stackleft) {
1705 		kstackleftmin = stackleft;
1706 		if (stackleft < kstackleftthres)
1707 			printf("warning: kernel stack left %d bytes"
1708 			    "(pid %u:lid %u)\n", stackleft,
1709 			    (u_int)l->l_proc->p_pid, (u_int)l->l_lid);
1710 	}
1711 
1712 	if (stackleft <= 0) {
1713 		panic("magic on the top of kernel stack changed for "
1714 		    "pid %u, lid %u: maybe kernel stack overflow",
1715 		    (u_int)l->l_proc->p_pid, (u_int)l->l_lid);
1716 	}
1717 }
1718 #endif /* KSTACK_CHECK_MAGIC */
1719 
1720 int
1721 proclist_foreach_call(struct proclist *list,
1722     int (*callback)(struct proc *, void *arg), void *arg)
1723 {
1724 	struct proc marker;
1725 	struct proc *p;
1726 	int ret = 0;
1727 
1728 	marker.p_flag = PK_MARKER;
1729 	mutex_enter(&proc_lock);
1730 	for (p = LIST_FIRST(list); ret == 0 && p != NULL;) {
1731 		if (p->p_flag & PK_MARKER) {
1732 			p = LIST_NEXT(p, p_list);
1733 			continue;
1734 		}
1735 		LIST_INSERT_AFTER(p, &marker, p_list);
1736 		ret = (*callback)(p, arg);
1737 		KASSERT(mutex_owned(&proc_lock));
1738 		p = LIST_NEXT(&marker, p_list);
1739 		LIST_REMOVE(&marker, p_list);
1740 	}
1741 	mutex_exit(&proc_lock);
1742 
1743 	return ret;
1744 }
1745 
1746 int
1747 proc_vmspace_getref(struct proc *p, struct vmspace **vm)
1748 {
1749 
1750 	/* XXXCDC: how should locking work here? */
1751 
1752 	/* curproc exception is for coredump. */
1753 
1754 	if ((p != curproc && (p->p_sflag & PS_WEXIT) != 0) ||
1755 	    (p->p_vmspace->vm_refcnt < 1)) {
1756 		return EFAULT;
1757 	}
1758 
1759 	uvmspace_addref(p->p_vmspace);
1760 	*vm = p->p_vmspace;
1761 
1762 	return 0;
1763 }
1764 
1765 /*
1766  * Acquire a write lock on the process credential.
1767  */
1768 void
1769 proc_crmod_enter(void)
1770 {
1771 	struct lwp *l = curlwp;
1772 	struct proc *p = l->l_proc;
1773 	kauth_cred_t oc;
1774 
1775 	/* Reset what needs to be reset in plimit. */
1776 	if (p->p_limit->pl_corename != defcorename) {
1777 		lim_setcorename(p, defcorename, 0);
1778 	}
1779 
1780 	mutex_enter(p->p_lock);
1781 
1782 	/* Ensure the LWP cached credentials are up to date. */
1783 	if ((oc = l->l_cred) != p->p_cred) {
1784 		kauth_cred_hold(p->p_cred);
1785 		l->l_cred = p->p_cred;
1786 		kauth_cred_free(oc);
1787 	}
1788 }
1789 
1790 /*
1791  * Set in a new process credential, and drop the write lock.  The credential
1792  * must have a reference already.  Optionally, free a no-longer required
1793  * credential.  The scheduler also needs to inspect p_cred, so we also
1794  * briefly acquire the sched state mutex.
1795  */
1796 void
1797 proc_crmod_leave(kauth_cred_t scred, kauth_cred_t fcred, bool sugid)
1798 {
1799 	struct lwp *l = curlwp, *l2;
1800 	struct proc *p = l->l_proc;
1801 	kauth_cred_t oc;
1802 
1803 	KASSERT(mutex_owned(p->p_lock));
1804 
1805 	/* Is there a new credential to set in? */
1806 	if (scred != NULL) {
1807 		p->p_cred = scred;
1808 		LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
1809 			if (l2 != l)
1810 				l2->l_prflag |= LPR_CRMOD;
1811 		}
1812 
1813 		/* Ensure the LWP cached credentials are up to date. */
1814 		if ((oc = l->l_cred) != scred) {
1815 			kauth_cred_hold(scred);
1816 			l->l_cred = scred;
1817 		}
1818 	} else
1819 		oc = NULL;	/* XXXgcc */
1820 
1821 	if (sugid) {
1822 		/*
1823 		 * Mark process as having changed credentials, stops
1824 		 * tracing etc.
1825 		 */
1826 		p->p_flag |= PK_SUGID;
1827 	}
1828 
1829 	mutex_exit(p->p_lock);
1830 
1831 	/* If there is a credential to be released, free it now. */
1832 	if (fcred != NULL) {
1833 		KASSERT(scred != NULL);
1834 		kauth_cred_free(fcred);
1835 		if (oc != scred)
1836 			kauth_cred_free(oc);
1837 	}
1838 }
1839 
1840 /*
1841  * proc_specific_key_create --
1842  *	Create a key for subsystem proc-specific data.
1843  */
1844 int
1845 proc_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor)
1846 {
1847 
1848 	return (specificdata_key_create(proc_specificdata_domain, keyp, dtor));
1849 }
1850 
1851 /*
1852  * proc_specific_key_delete --
1853  *	Delete a key for subsystem proc-specific data.
1854  */
1855 void
1856 proc_specific_key_delete(specificdata_key_t key)
1857 {
1858 
1859 	specificdata_key_delete(proc_specificdata_domain, key);
1860 }
1861 
1862 /*
1863  * proc_initspecific --
1864  *	Initialize a proc's specificdata container.
1865  */
1866 void
1867 proc_initspecific(struct proc *p)
1868 {
1869 	int error __diagused;
1870 
1871 	error = specificdata_init(proc_specificdata_domain, &p->p_specdataref);
1872 	KASSERT(error == 0);
1873 }
1874 
1875 /*
1876  * proc_finispecific --
1877  *	Finalize a proc's specificdata container.
1878  */
1879 void
1880 proc_finispecific(struct proc *p)
1881 {
1882 
1883 	specificdata_fini(proc_specificdata_domain, &p->p_specdataref);
1884 }
1885 
1886 /*
1887  * proc_getspecific --
1888  *	Return proc-specific data corresponding to the specified key.
1889  */
1890 void *
1891 proc_getspecific(struct proc *p, specificdata_key_t key)
1892 {
1893 
1894 	return (specificdata_getspecific(proc_specificdata_domain,
1895 					 &p->p_specdataref, key));
1896 }
1897 
1898 /*
1899  * proc_setspecific --
1900  *	Set proc-specific data corresponding to the specified key.
1901  */
1902 void
1903 proc_setspecific(struct proc *p, specificdata_key_t key, void *data)
1904 {
1905 
1906 	specificdata_setspecific(proc_specificdata_domain,
1907 				 &p->p_specdataref, key, data);
1908 }
1909 
1910 int
1911 proc_uidmatch(kauth_cred_t cred, kauth_cred_t target)
1912 {
1913 	int r = 0;
1914 
1915 	if (kauth_cred_getuid(cred) != kauth_cred_getuid(target) ||
1916 	    kauth_cred_getuid(cred) != kauth_cred_getsvuid(target)) {
1917 		/*
1918 		 * suid proc of ours or proc not ours
1919 		 */
1920 		r = EPERM;
1921 	} else if (kauth_cred_getgid(target) != kauth_cred_getsvgid(target)) {
1922 		/*
1923 		 * sgid proc has sgid back to us temporarily
1924 		 */
1925 		r = EPERM;
1926 	} else {
1927 		/*
1928 		 * our rgid must be in target's group list (ie,
1929 		 * sub-processes started by a sgid process)
1930 		 */
1931 		int ismember = 0;
1932 
1933 		if (kauth_cred_ismember_gid(cred,
1934 		    kauth_cred_getgid(target), &ismember) != 0 ||
1935 		    !ismember)
1936 			r = EPERM;
1937 	}
1938 
1939 	return (r);
1940 }
1941 
1942 /*
1943  * sysctl stuff
1944  */
1945 
1946 #define KERN_PROCSLOP	(5 * sizeof(struct kinfo_proc))
1947 
1948 static const u_int sysctl_flagmap[] = {
1949 	PK_ADVLOCK, P_ADVLOCK,
1950 	PK_EXEC, P_EXEC,
1951 	PK_NOCLDWAIT, P_NOCLDWAIT,
1952 	PK_32, P_32,
1953 	PK_CLDSIGIGN, P_CLDSIGIGN,
1954 	PK_SUGID, P_SUGID,
1955 	0
1956 };
1957 
1958 static const u_int sysctl_sflagmap[] = {
1959 	PS_NOCLDSTOP, P_NOCLDSTOP,
1960 	PS_WEXIT, P_WEXIT,
1961 	PS_STOPFORK, P_STOPFORK,
1962 	PS_STOPEXEC, P_STOPEXEC,
1963 	PS_STOPEXIT, P_STOPEXIT,
1964 	0
1965 };
1966 
1967 static const u_int sysctl_slflagmap[] = {
1968 	PSL_TRACED, P_TRACED,
1969 	PSL_CHTRACED, P_CHTRACED,
1970 	PSL_SYSCALL, P_SYSCALL,
1971 	0
1972 };
1973 
1974 static const u_int sysctl_lflagmap[] = {
1975 	PL_CONTROLT, P_CONTROLT,
1976 	PL_PPWAIT, P_PPWAIT,
1977 	0
1978 };
1979 
1980 static const u_int sysctl_stflagmap[] = {
1981 	PST_PROFIL, P_PROFIL,
1982 	0
1983 
1984 };
1985 
1986 /* used by kern_lwp also */
1987 const u_int sysctl_lwpflagmap[] = {
1988 	LW_SINTR, L_SINTR,
1989 	LW_SYSTEM, L_SYSTEM,
1990 	0
1991 };
1992 
1993 /*
1994  * Find the most ``active'' lwp of a process and return it for ps display
1995  * purposes
1996  */
1997 static struct lwp *
1998 proc_active_lwp(struct proc *p)
1999 {
2000 	static const int ostat[] = {
2001 		0,
2002 		2,	/* LSIDL */
2003 		6,	/* LSRUN */
2004 		5,	/* LSSLEEP */
2005 		4,	/* LSSTOP */
2006 		0,	/* LSZOMB */
2007 		1,	/* LSDEAD */
2008 		7,	/* LSONPROC */
2009 		3	/* LSSUSPENDED */
2010 	};
2011 
2012 	struct lwp *l, *lp = NULL;
2013 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
2014 		KASSERT(l->l_stat >= 0 && l->l_stat < __arraycount(ostat));
2015 		if (lp == NULL ||
2016 		    ostat[l->l_stat] > ostat[lp->l_stat] ||
2017 		    (ostat[l->l_stat] == ostat[lp->l_stat] &&
2018 		    l->l_cpticks > lp->l_cpticks)) {
2019 			lp = l;
2020 			continue;
2021 		}
2022 	}
2023 	return lp;
2024 }
2025 
2026 static int
2027 sysctl_doeproc(SYSCTLFN_ARGS)
2028 {
2029 	union {
2030 		struct kinfo_proc kproc;
2031 		struct kinfo_proc2 kproc2;
2032 	} *kbuf;
2033 	struct proc *p, *next, *marker;
2034 	char *where, *dp;
2035 	int type, op, arg, error;
2036 	u_int elem_size, kelem_size, elem_count;
2037 	size_t buflen, needed;
2038 	bool match, zombie, mmmbrains;
2039 	const bool allowaddr = get_expose_address(curproc);
2040 
2041 	if (namelen == 1 && name[0] == CTL_QUERY)
2042 		return (sysctl_query(SYSCTLFN_CALL(rnode)));
2043 
2044 	dp = where = oldp;
2045 	buflen = where != NULL ? *oldlenp : 0;
2046 	error = 0;
2047 	needed = 0;
2048 	type = rnode->sysctl_num;
2049 
2050 	if (type == KERN_PROC) {
2051 		if (namelen == 0)
2052 			return EINVAL;
2053 		switch (op = name[0]) {
2054 		case KERN_PROC_ALL:
2055 			if (namelen != 1)
2056 				return EINVAL;
2057 			arg = 0;
2058 			break;
2059 		default:
2060 			if (namelen != 2)
2061 				return EINVAL;
2062 			arg = name[1];
2063 			break;
2064 		}
2065 		elem_count = 0;	/* Hush little compiler, don't you cry */
2066 		kelem_size = elem_size = sizeof(kbuf->kproc);
2067 	} else {
2068 		if (namelen != 4)
2069 			return EINVAL;
2070 		op = name[0];
2071 		arg = name[1];
2072 		elem_size = name[2];
2073 		elem_count = name[3];
2074 		kelem_size = sizeof(kbuf->kproc2);
2075 	}
2076 
2077 	sysctl_unlock();
2078 
2079 	kbuf = kmem_zalloc(sizeof(*kbuf), KM_SLEEP);
2080 	marker = kmem_alloc(sizeof(*marker), KM_SLEEP);
2081 	marker->p_flag = PK_MARKER;
2082 
2083 	mutex_enter(&proc_lock);
2084 	/*
2085 	 * Start with zombies to prevent reporting processes twice, in case they
2086 	 * are dying and being moved from the list of alive processes to zombies.
2087 	 */
2088 	mmmbrains = true;
2089 	for (p = LIST_FIRST(&zombproc);; p = next) {
2090 		if (p == NULL) {
2091 			if (mmmbrains) {
2092 				p = LIST_FIRST(&allproc);
2093 				mmmbrains = false;
2094 			}
2095 			if (p == NULL)
2096 				break;
2097 		}
2098 		next = LIST_NEXT(p, p_list);
2099 		if ((p->p_flag & PK_MARKER) != 0)
2100 			continue;
2101 
2102 		/*
2103 		 * Skip embryonic processes.
2104 		 */
2105 		if (p->p_stat == SIDL)
2106 			continue;
2107 
2108 		mutex_enter(p->p_lock);
2109 		error = kauth_authorize_process(l->l_cred,
2110 		    KAUTH_PROCESS_CANSEE, p,
2111 		    KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_EPROC), NULL, NULL);
2112 		if (error != 0) {
2113 			mutex_exit(p->p_lock);
2114 			continue;
2115 		}
2116 
2117 		/*
2118 		 * Hande all the operations in one switch on the cost of
2119 		 * algorithm complexity is on purpose. The win splitting this
2120 		 * function into several similar copies makes maintenance burden
2121 		 * burden, code grow and boost is neglible in practical systems.
2122 		 */
2123 		switch (op) {
2124 		case KERN_PROC_PID:
2125 			match = (p->p_pid == (pid_t)arg);
2126 			break;
2127 
2128 		case KERN_PROC_PGRP:
2129 			match = (p->p_pgrp->pg_id == (pid_t)arg);
2130 			break;
2131 
2132 		case KERN_PROC_SESSION:
2133 			match = (p->p_session->s_sid == (pid_t)arg);
2134 			break;
2135 
2136 		case KERN_PROC_TTY:
2137 			match = true;
2138 			if (arg == (int) KERN_PROC_TTY_REVOKE) {
2139 				if ((p->p_lflag & PL_CONTROLT) == 0 ||
2140 				    p->p_session->s_ttyp == NULL ||
2141 				    p->p_session->s_ttyvp != NULL) {
2142 				    	match = false;
2143 				}
2144 			} else if ((p->p_lflag & PL_CONTROLT) == 0 ||
2145 			    p->p_session->s_ttyp == NULL) {
2146 				if ((dev_t)arg != KERN_PROC_TTY_NODEV) {
2147 					match = false;
2148 				}
2149 			} else if (p->p_session->s_ttyp->t_dev != (dev_t)arg) {
2150 				match = false;
2151 			}
2152 			break;
2153 
2154 		case KERN_PROC_UID:
2155 			match = (kauth_cred_geteuid(p->p_cred) == (uid_t)arg);
2156 			break;
2157 
2158 		case KERN_PROC_RUID:
2159 			match = (kauth_cred_getuid(p->p_cred) == (uid_t)arg);
2160 			break;
2161 
2162 		case KERN_PROC_GID:
2163 			match = (kauth_cred_getegid(p->p_cred) == (uid_t)arg);
2164 			break;
2165 
2166 		case KERN_PROC_RGID:
2167 			match = (kauth_cred_getgid(p->p_cred) == (uid_t)arg);
2168 			break;
2169 
2170 		case KERN_PROC_ALL:
2171 			match = true;
2172 			/* allow everything */
2173 			break;
2174 
2175 		default:
2176 			error = EINVAL;
2177 			mutex_exit(p->p_lock);
2178 			goto cleanup;
2179 		}
2180 		if (!match) {
2181 			mutex_exit(p->p_lock);
2182 			continue;
2183 		}
2184 
2185 		/*
2186 		 * Grab a hold on the process.
2187 		 */
2188 		if (mmmbrains) {
2189 			zombie = true;
2190 		} else {
2191 			zombie = !rw_tryenter(&p->p_reflock, RW_READER);
2192 		}
2193 		if (zombie) {
2194 			LIST_INSERT_AFTER(p, marker, p_list);
2195 		}
2196 
2197 		if (buflen >= elem_size &&
2198 		    (type == KERN_PROC || elem_count > 0)) {
2199 			ruspace(p);	/* Update process vm resource use */
2200 
2201 			if (type == KERN_PROC) {
2202 				fill_proc(p, &kbuf->kproc.kp_proc, allowaddr);
2203 				fill_eproc(p, &kbuf->kproc.kp_eproc, zombie,
2204 				    allowaddr);
2205 			} else {
2206 				fill_kproc2(p, &kbuf->kproc2, zombie,
2207 				    allowaddr);
2208 				elem_count--;
2209 			}
2210 			mutex_exit(p->p_lock);
2211 			mutex_exit(&proc_lock);
2212 			/*
2213 			 * Copy out elem_size, but not larger than kelem_size
2214 			 */
2215 			error = sysctl_copyout(l, kbuf, dp,
2216 			    uimin(kelem_size, elem_size));
2217 			mutex_enter(&proc_lock);
2218 			if (error) {
2219 				goto bah;
2220 			}
2221 			dp += elem_size;
2222 			buflen -= elem_size;
2223 		} else {
2224 			mutex_exit(p->p_lock);
2225 		}
2226 		needed += elem_size;
2227 
2228 		/*
2229 		 * Release reference to process.
2230 		 */
2231 	 	if (zombie) {
2232 			next = LIST_NEXT(marker, p_list);
2233  			LIST_REMOVE(marker, p_list);
2234 		} else {
2235 			rw_exit(&p->p_reflock);
2236 			next = LIST_NEXT(p, p_list);
2237 		}
2238 
2239 		/*
2240 		 * Short-circuit break quickly!
2241 		 */
2242 		if (op == KERN_PROC_PID)
2243                 	break;
2244 	}
2245 	mutex_exit(&proc_lock);
2246 
2247 	if (where != NULL) {
2248 		*oldlenp = dp - where;
2249 		if (needed > *oldlenp) {
2250 			error = ENOMEM;
2251 			goto out;
2252 		}
2253 	} else {
2254 		needed += KERN_PROCSLOP;
2255 		*oldlenp = needed;
2256 	}
2257 	kmem_free(kbuf, sizeof(*kbuf));
2258 	kmem_free(marker, sizeof(*marker));
2259 	sysctl_relock();
2260 	return 0;
2261  bah:
2262  	if (zombie)
2263  		LIST_REMOVE(marker, p_list);
2264 	else
2265 		rw_exit(&p->p_reflock);
2266  cleanup:
2267 	mutex_exit(&proc_lock);
2268  out:
2269 	kmem_free(kbuf, sizeof(*kbuf));
2270 	kmem_free(marker, sizeof(*marker));
2271 	sysctl_relock();
2272 	return error;
2273 }
2274 
2275 int
2276 copyin_psstrings(struct proc *p, struct ps_strings *arginfo)
2277 {
2278 #if !defined(_RUMPKERNEL)
2279 	int retval;
2280 
2281 	if (p->p_flag & PK_32) {
2282 		MODULE_HOOK_CALL(kern_proc32_copyin_hook, (p, arginfo),
2283 		    enosys(), retval);
2284 		return retval;
2285 	}
2286 #endif /* !defined(_RUMPKERNEL) */
2287 
2288 	return copyin_proc(p, (void *)p->p_psstrp, arginfo, sizeof(*arginfo));
2289 }
2290 
2291 static int
2292 copy_procargs_sysctl_cb(void *cookie_, const void *src, size_t off, size_t len)
2293 {
2294 	void **cookie = cookie_;
2295 	struct lwp *l = cookie[0];
2296 	char *dst = cookie[1];
2297 
2298 	return sysctl_copyout(l, src, dst + off, len);
2299 }
2300 
2301 /*
2302  * sysctl helper routine for kern.proc_args pseudo-subtree.
2303  */
2304 static int
2305 sysctl_kern_proc_args(SYSCTLFN_ARGS)
2306 {
2307 	struct ps_strings pss;
2308 	struct proc *p;
2309 	pid_t pid;
2310 	int type, error;
2311 	void *cookie[2];
2312 
2313 	if (namelen == 1 && name[0] == CTL_QUERY)
2314 		return (sysctl_query(SYSCTLFN_CALL(rnode)));
2315 
2316 	if (newp != NULL || namelen != 2)
2317 		return (EINVAL);
2318 	pid = name[0];
2319 	type = name[1];
2320 
2321 	switch (type) {
2322 	case KERN_PROC_PATHNAME:
2323 		sysctl_unlock();
2324 		error = fill_pathname(l, pid, oldp, oldlenp);
2325 		sysctl_relock();
2326 		return error;
2327 
2328 	case KERN_PROC_CWD:
2329 		sysctl_unlock();
2330 		error = fill_cwd(l, pid, oldp, oldlenp);
2331 		sysctl_relock();
2332 		return error;
2333 
2334 	case KERN_PROC_ARGV:
2335 	case KERN_PROC_NARGV:
2336 	case KERN_PROC_ENV:
2337 	case KERN_PROC_NENV:
2338 		/* ok */
2339 		break;
2340 	default:
2341 		return (EINVAL);
2342 	}
2343 
2344 	sysctl_unlock();
2345 
2346 	/* check pid */
2347 	mutex_enter(&proc_lock);
2348 	if ((p = proc_find(pid)) == NULL) {
2349 		error = EINVAL;
2350 		goto out_locked;
2351 	}
2352 	mutex_enter(p->p_lock);
2353 
2354 	/* Check permission. */
2355 	if (type == KERN_PROC_ARGV || type == KERN_PROC_NARGV)
2356 		error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
2357 		    p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ARGS), NULL, NULL);
2358 	else if (type == KERN_PROC_ENV || type == KERN_PROC_NENV)
2359 		error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
2360 		    p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENV), NULL, NULL);
2361 	else
2362 		error = EINVAL; /* XXXGCC */
2363 	if (error) {
2364 		mutex_exit(p->p_lock);
2365 		goto out_locked;
2366 	}
2367 
2368 	if (oldp == NULL) {
2369 		if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV)
2370 			*oldlenp = sizeof (int);
2371 		else
2372 			*oldlenp = ARG_MAX;	/* XXX XXX XXX */
2373 		error = 0;
2374 		mutex_exit(p->p_lock);
2375 		goto out_locked;
2376 	}
2377 
2378 	/*
2379 	 * Zombies don't have a stack, so we can't read their psstrings.
2380 	 * System processes also don't have a user stack.
2381 	 */
2382 	if (P_ZOMBIE(p) || (p->p_flag & PK_SYSTEM) != 0) {
2383 		error = EINVAL;
2384 		mutex_exit(p->p_lock);
2385 		goto out_locked;
2386 	}
2387 
2388 	error = rw_tryenter(&p->p_reflock, RW_READER) ? 0 : EBUSY;
2389 	mutex_exit(p->p_lock);
2390 	if (error) {
2391 		goto out_locked;
2392 	}
2393 	mutex_exit(&proc_lock);
2394 
2395 	if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV) {
2396 		int value;
2397 		if ((error = copyin_psstrings(p, &pss)) == 0) {
2398 			if (type == KERN_PROC_NARGV)
2399 				value = pss.ps_nargvstr;
2400 			else
2401 				value = pss.ps_nenvstr;
2402 			error = sysctl_copyout(l, &value, oldp, sizeof(value));
2403 			*oldlenp = sizeof(value);
2404 		}
2405 	} else {
2406 		cookie[0] = l;
2407 		cookie[1] = oldp;
2408 		error = copy_procargs(p, type, oldlenp,
2409 		    copy_procargs_sysctl_cb, cookie);
2410 	}
2411 	rw_exit(&p->p_reflock);
2412 	sysctl_relock();
2413 	return error;
2414 
2415 out_locked:
2416 	mutex_exit(&proc_lock);
2417 	sysctl_relock();
2418 	return error;
2419 }
2420 
2421 int
2422 copy_procargs(struct proc *p, int oid, size_t *limit,
2423     int (*cb)(void *, const void *, size_t, size_t), void *cookie)
2424 {
2425 	struct ps_strings pss;
2426 	size_t len, i, loaded, entry_len;
2427 	struct uio auio;
2428 	struct iovec aiov;
2429 	int error, argvlen;
2430 	char *arg;
2431 	char **argv;
2432 	vaddr_t user_argv;
2433 	struct vmspace *vmspace;
2434 
2435 	/*
2436 	 * Allocate a temporary buffer to hold the argument vector and
2437 	 * the arguments themselve.
2438 	 */
2439 	arg = kmem_alloc(PAGE_SIZE, KM_SLEEP);
2440 	argv = kmem_alloc(PAGE_SIZE, KM_SLEEP);
2441 
2442 	/*
2443 	 * Lock the process down in memory.
2444 	 */
2445 	vmspace = p->p_vmspace;
2446 	uvmspace_addref(vmspace);
2447 
2448 	/*
2449 	 * Read in the ps_strings structure.
2450 	 */
2451 	if ((error = copyin_psstrings(p, &pss)) != 0)
2452 		goto done;
2453 
2454 	/*
2455 	 * Now read the address of the argument vector.
2456 	 */
2457 	switch (oid) {
2458 	case KERN_PROC_ARGV:
2459 		user_argv = (uintptr_t)pss.ps_argvstr;
2460 		argvlen = pss.ps_nargvstr;
2461 		break;
2462 	case KERN_PROC_ENV:
2463 		user_argv = (uintptr_t)pss.ps_envstr;
2464 		argvlen = pss.ps_nenvstr;
2465 		break;
2466 	default:
2467 		error = EINVAL;
2468 		goto done;
2469 	}
2470 
2471 	if (argvlen < 0) {
2472 		error = EIO;
2473 		goto done;
2474 	}
2475 
2476 
2477 	/*
2478 	 * Now copy each string.
2479 	 */
2480 	len = 0; /* bytes written to user buffer */
2481 	loaded = 0; /* bytes from argv already processed */
2482 	i = 0; /* To make compiler happy */
2483 	entry_len = PROC_PTRSZ(p);
2484 
2485 	for (; argvlen; --argvlen) {
2486 		int finished = 0;
2487 		vaddr_t base;
2488 		size_t xlen;
2489 		int j;
2490 
2491 		if (loaded == 0) {
2492 			size_t rem = entry_len * argvlen;
2493 			loaded = MIN(rem, PAGE_SIZE);
2494 			error = copyin_vmspace(vmspace,
2495 			    (const void *)user_argv, argv, loaded);
2496 			if (error)
2497 				break;
2498 			user_argv += loaded;
2499 			i = 0;
2500 		}
2501 
2502 #if !defined(_RUMPKERNEL)
2503 		if (p->p_flag & PK_32)
2504 			MODULE_HOOK_CALL(kern_proc32_base_hook,
2505 			    (argv, i++), 0, base);
2506 		else
2507 #endif /* !defined(_RUMPKERNEL) */
2508 			base = (vaddr_t)argv[i++];
2509 		loaded -= entry_len;
2510 
2511 		/*
2512 		 * The program has messed around with its arguments,
2513 		 * possibly deleting some, and replacing them with
2514 		 * NULL's. Treat this as the last argument and not
2515 		 * a failure.
2516 		 */
2517 		if (base == 0)
2518 			break;
2519 
2520 		while (!finished) {
2521 			xlen = PAGE_SIZE - (base & PAGE_MASK);
2522 
2523 			aiov.iov_base = arg;
2524 			aiov.iov_len = PAGE_SIZE;
2525 			auio.uio_iov = &aiov;
2526 			auio.uio_iovcnt = 1;
2527 			auio.uio_offset = base;
2528 			auio.uio_resid = xlen;
2529 			auio.uio_rw = UIO_READ;
2530 			UIO_SETUP_SYSSPACE(&auio);
2531 			error = uvm_io(&vmspace->vm_map, &auio, 0);
2532 			if (error)
2533 				goto done;
2534 
2535 			/* Look for the end of the string */
2536 			for (j = 0; j < xlen; j++) {
2537 				if (arg[j] == '\0') {
2538 					xlen = j + 1;
2539 					finished = 1;
2540 					break;
2541 				}
2542 			}
2543 
2544 			/* Check for user buffer overflow */
2545 			if (len + xlen > *limit) {
2546 				finished = 1;
2547 				if (len > *limit)
2548 					xlen = 0;
2549 				else
2550 					xlen = *limit - len;
2551 			}
2552 
2553 			/* Copyout the page */
2554 			error = (*cb)(cookie, arg, len, xlen);
2555 			if (error)
2556 				goto done;
2557 
2558 			len += xlen;
2559 			base += xlen;
2560 		}
2561 	}
2562 	*limit = len;
2563 
2564 done:
2565 	kmem_free(argv, PAGE_SIZE);
2566 	kmem_free(arg, PAGE_SIZE);
2567 	uvmspace_free(vmspace);
2568 	return error;
2569 }
2570 
2571 /*
2572  * Fill in a proc structure for the specified process.
2573  */
2574 static void
2575 fill_proc(const struct proc *psrc, struct proc *p, bool allowaddr)
2576 {
2577 	COND_SET_STRUCT(p->p_list, psrc->p_list, allowaddr);
2578 	memset(&p->p_auxlock, 0, sizeof(p->p_auxlock));
2579 	COND_SET_STRUCT(p->p_lock, psrc->p_lock, allowaddr);
2580 	memset(&p->p_stmutex, 0, sizeof(p->p_stmutex));
2581 	memset(&p->p_reflock, 0, sizeof(p->p_reflock));
2582 	COND_SET_STRUCT(p->p_waitcv, psrc->p_waitcv, allowaddr);
2583 	COND_SET_STRUCT(p->p_lwpcv, psrc->p_lwpcv, allowaddr);
2584 	COND_SET_PTR(p->p_cred, psrc->p_cred, allowaddr);
2585 	COND_SET_PTR(p->p_fd, psrc->p_fd, allowaddr);
2586 	COND_SET_PTR(p->p_cwdi, psrc->p_cwdi, allowaddr);
2587 	COND_SET_PTR(p->p_stats, psrc->p_stats, allowaddr);
2588 	COND_SET_PTR(p->p_limit, psrc->p_limit, allowaddr);
2589 	COND_SET_PTR(p->p_vmspace, psrc->p_vmspace, allowaddr);
2590 	COND_SET_PTR(p->p_sigacts, psrc->p_sigacts, allowaddr);
2591 	COND_SET_PTR(p->p_aio, psrc->p_aio, allowaddr);
2592 	p->p_mqueue_cnt = psrc->p_mqueue_cnt;
2593 	memset(&p->p_specdataref, 0, sizeof(p->p_specdataref));
2594 	p->p_exitsig = psrc->p_exitsig;
2595 	p->p_flag = psrc->p_flag;
2596 	p->p_sflag = psrc->p_sflag;
2597 	p->p_slflag = psrc->p_slflag;
2598 	p->p_lflag = psrc->p_lflag;
2599 	p->p_stflag = psrc->p_stflag;
2600 	p->p_stat = psrc->p_stat;
2601 	p->p_trace_enabled = psrc->p_trace_enabled;
2602 	p->p_pid = psrc->p_pid;
2603 	COND_SET_STRUCT(p->p_pglist, psrc->p_pglist, allowaddr);
2604 	COND_SET_PTR(p->p_pptr, psrc->p_pptr, allowaddr);
2605 	COND_SET_STRUCT(p->p_sibling, psrc->p_sibling, allowaddr);
2606 	COND_SET_STRUCT(p->p_children, psrc->p_children, allowaddr);
2607 	COND_SET_STRUCT(p->p_lwps, psrc->p_lwps, allowaddr);
2608 	COND_SET_PTR(p->p_raslist, psrc->p_raslist, allowaddr);
2609 	p->p_nlwps = psrc->p_nlwps;
2610 	p->p_nzlwps = psrc->p_nzlwps;
2611 	p->p_nrlwps = psrc->p_nrlwps;
2612 	p->p_nlwpwait = psrc->p_nlwpwait;
2613 	p->p_ndlwps = psrc->p_ndlwps;
2614 	p->p_nstopchild = psrc->p_nstopchild;
2615 	p->p_waited = psrc->p_waited;
2616 	COND_SET_PTR(p->p_zomblwp, psrc->p_zomblwp, allowaddr);
2617 	COND_SET_PTR(p->p_vforklwp, psrc->p_vforklwp, allowaddr);
2618 	COND_SET_PTR(p->p_sched_info, psrc->p_sched_info, allowaddr);
2619 	p->p_estcpu = psrc->p_estcpu;
2620 	p->p_estcpu_inherited = psrc->p_estcpu_inherited;
2621 	p->p_forktime = psrc->p_forktime;
2622 	p->p_pctcpu = psrc->p_pctcpu;
2623 	COND_SET_PTR(p->p_opptr, psrc->p_opptr, allowaddr);
2624 	COND_SET_PTR(p->p_timers, psrc->p_timers, allowaddr);
2625 	p->p_rtime = psrc->p_rtime;
2626 	p->p_uticks = psrc->p_uticks;
2627 	p->p_sticks = psrc->p_sticks;
2628 	p->p_iticks = psrc->p_iticks;
2629 	p->p_xutime = psrc->p_xutime;
2630 	p->p_xstime = psrc->p_xstime;
2631 	p->p_traceflag = psrc->p_traceflag;
2632 	COND_SET_PTR(p->p_tracep, psrc->p_tracep, allowaddr);
2633 	COND_SET_PTR(p->p_textvp, psrc->p_textvp, allowaddr);
2634 	COND_SET_PTR(p->p_emul, psrc->p_emul, allowaddr);
2635 	COND_SET_PTR(p->p_emuldata, psrc->p_emuldata, allowaddr);
2636 	COND_SET_CPTR(p->p_execsw, psrc->p_execsw, allowaddr);
2637 	COND_SET_STRUCT(p->p_klist, psrc->p_klist, allowaddr);
2638 	COND_SET_STRUCT(p->p_sigwaiters, psrc->p_sigwaiters, allowaddr);
2639 	COND_SET_STRUCT(p->p_sigpend.sp_info, psrc->p_sigpend.sp_info,
2640 	    allowaddr);
2641 	p->p_sigpend.sp_set = psrc->p_sigpend.sp_set;
2642 	COND_SET_PTR(p->p_lwpctl, psrc->p_lwpctl, allowaddr);
2643 	p->p_ppid = psrc->p_ppid;
2644 	p->p_oppid = psrc->p_oppid;
2645 	COND_SET_PTR(p->p_path, psrc->p_path, allowaddr);
2646 	p->p_sigctx = psrc->p_sigctx;
2647 	p->p_nice = psrc->p_nice;
2648 	memcpy(p->p_comm, psrc->p_comm, sizeof(p->p_comm));
2649 	COND_SET_PTR(p->p_pgrp, psrc->p_pgrp, allowaddr);
2650 	COND_SET_VALUE(p->p_psstrp, psrc->p_psstrp, allowaddr);
2651 	p->p_pax = psrc->p_pax;
2652 	p->p_xexit = psrc->p_xexit;
2653 	p->p_xsig = psrc->p_xsig;
2654 	p->p_acflag = psrc->p_acflag;
2655 	COND_SET_STRUCT(p->p_md, psrc->p_md, allowaddr);
2656 	p->p_stackbase = psrc->p_stackbase;
2657 	COND_SET_PTR(p->p_dtrace, psrc->p_dtrace, allowaddr);
2658 }
2659 
2660 /*
2661  * Fill in an eproc structure for the specified process.
2662  */
2663 void
2664 fill_eproc(struct proc *p, struct eproc *ep, bool zombie, bool allowaddr)
2665 {
2666 	struct tty *tp;
2667 	struct lwp *l;
2668 
2669 	KASSERT(mutex_owned(&proc_lock));
2670 	KASSERT(mutex_owned(p->p_lock));
2671 
2672 	COND_SET_PTR(ep->e_paddr, p, allowaddr);
2673 	COND_SET_PTR(ep->e_sess, p->p_session, allowaddr);
2674 	if (p->p_cred) {
2675 		kauth_cred_topcred(p->p_cred, &ep->e_pcred);
2676 		kauth_cred_toucred(p->p_cred, &ep->e_ucred);
2677 	}
2678 	if (p->p_stat != SIDL && !P_ZOMBIE(p) && !zombie) {
2679 		struct vmspace *vm = p->p_vmspace;
2680 
2681 		ep->e_vm.vm_rssize = vm_resident_count(vm);
2682 		ep->e_vm.vm_tsize = vm->vm_tsize;
2683 		ep->e_vm.vm_dsize = vm->vm_dsize;
2684 		ep->e_vm.vm_ssize = vm->vm_ssize;
2685 		ep->e_vm.vm_map.size = vm->vm_map.size;
2686 
2687 		/* Pick the primary (first) LWP */
2688 		l = proc_active_lwp(p);
2689 		KASSERT(l != NULL);
2690 		lwp_lock(l);
2691 		if (l->l_wchan)
2692 			strncpy(ep->e_wmesg, l->l_wmesg, WMESGLEN);
2693 		lwp_unlock(l);
2694 	}
2695 	ep->e_ppid = p->p_ppid;
2696 	if (p->p_pgrp && p->p_session) {
2697 		ep->e_pgid = p->p_pgrp->pg_id;
2698 		ep->e_jobc = p->p_pgrp->pg_jobc;
2699 		ep->e_sid = p->p_session->s_sid;
2700 		if ((p->p_lflag & PL_CONTROLT) &&
2701 		    (tp = p->p_session->s_ttyp)) {
2702 			ep->e_tdev = tp->t_dev;
2703 			ep->e_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PGID;
2704 			COND_SET_PTR(ep->e_tsess, tp->t_session, allowaddr);
2705 		} else
2706 			ep->e_tdev = (uint32_t)NODEV;
2707 		ep->e_flag = p->p_session->s_ttyvp ? EPROC_CTTY : 0;
2708 		if (SESS_LEADER(p))
2709 			ep->e_flag |= EPROC_SLEADER;
2710 		strncpy(ep->e_login, p->p_session->s_login, MAXLOGNAME);
2711 	}
2712 	ep->e_xsize = ep->e_xrssize = 0;
2713 	ep->e_xccount = ep->e_xswrss = 0;
2714 }
2715 
2716 /*
2717  * Fill in a kinfo_proc2 structure for the specified process.
2718  */
2719 void
2720 fill_kproc2(struct proc *p, struct kinfo_proc2 *ki, bool zombie, bool allowaddr)
2721 {
2722 	struct tty *tp;
2723 	struct lwp *l, *l2;
2724 	struct timeval ut, st, rt;
2725 	sigset_t ss1, ss2;
2726 	struct rusage ru;
2727 	struct vmspace *vm;
2728 
2729 	KASSERT(mutex_owned(&proc_lock));
2730 	KASSERT(mutex_owned(p->p_lock));
2731 
2732 	sigemptyset(&ss1);
2733 	sigemptyset(&ss2);
2734 
2735 	COND_SET_VALUE(ki->p_paddr, PTRTOUINT64(p), allowaddr);
2736 	COND_SET_VALUE(ki->p_fd, PTRTOUINT64(p->p_fd), allowaddr);
2737 	COND_SET_VALUE(ki->p_cwdi, PTRTOUINT64(p->p_cwdi), allowaddr);
2738 	COND_SET_VALUE(ki->p_stats, PTRTOUINT64(p->p_stats), allowaddr);
2739 	COND_SET_VALUE(ki->p_limit, PTRTOUINT64(p->p_limit), allowaddr);
2740 	COND_SET_VALUE(ki->p_vmspace, PTRTOUINT64(p->p_vmspace), allowaddr);
2741 	COND_SET_VALUE(ki->p_sigacts, PTRTOUINT64(p->p_sigacts), allowaddr);
2742 	COND_SET_VALUE(ki->p_sess, PTRTOUINT64(p->p_session), allowaddr);
2743 	ki->p_tsess = 0;	/* may be changed if controlling tty below */
2744 	COND_SET_VALUE(ki->p_ru, PTRTOUINT64(&p->p_stats->p_ru), allowaddr);
2745 	ki->p_eflag = 0;
2746 	ki->p_exitsig = p->p_exitsig;
2747 	ki->p_flag = L_INMEM;   /* Process never swapped out */
2748 	ki->p_flag |= sysctl_map_flags(sysctl_flagmap, p->p_flag);
2749 	ki->p_flag |= sysctl_map_flags(sysctl_sflagmap, p->p_sflag);
2750 	ki->p_flag |= sysctl_map_flags(sysctl_slflagmap, p->p_slflag);
2751 	ki->p_flag |= sysctl_map_flags(sysctl_lflagmap, p->p_lflag);
2752 	ki->p_flag |= sysctl_map_flags(sysctl_stflagmap, p->p_stflag);
2753 	ki->p_pid = p->p_pid;
2754 	ki->p_ppid = p->p_ppid;
2755 	ki->p_uid = kauth_cred_geteuid(p->p_cred);
2756 	ki->p_ruid = kauth_cred_getuid(p->p_cred);
2757 	ki->p_gid = kauth_cred_getegid(p->p_cred);
2758 	ki->p_rgid = kauth_cred_getgid(p->p_cred);
2759 	ki->p_svuid = kauth_cred_getsvuid(p->p_cred);
2760 	ki->p_svgid = kauth_cred_getsvgid(p->p_cred);
2761 	ki->p_ngroups = kauth_cred_ngroups(p->p_cred);
2762 	kauth_cred_getgroups(p->p_cred, ki->p_groups,
2763 	    uimin(ki->p_ngroups, sizeof(ki->p_groups) / sizeof(ki->p_groups[0])),
2764 	    UIO_SYSSPACE);
2765 
2766 	ki->p_uticks = p->p_uticks;
2767 	ki->p_sticks = p->p_sticks;
2768 	ki->p_iticks = p->p_iticks;
2769 	ki->p_tpgid = NO_PGID;	/* may be changed if controlling tty below */
2770 	COND_SET_VALUE(ki->p_tracep, PTRTOUINT64(p->p_tracep), allowaddr);
2771 	ki->p_traceflag = p->p_traceflag;
2772 
2773 	memcpy(&ki->p_sigignore, &p->p_sigctx.ps_sigignore,sizeof(ki_sigset_t));
2774 	memcpy(&ki->p_sigcatch, &p->p_sigctx.ps_sigcatch, sizeof(ki_sigset_t));
2775 
2776 	ki->p_cpticks = 0;
2777 	ki->p_pctcpu = p->p_pctcpu;
2778 	ki->p_estcpu = 0;
2779 	ki->p_stat = p->p_stat; /* Will likely be overridden by LWP status */
2780 	ki->p_realstat = p->p_stat;
2781 	ki->p_nice = p->p_nice;
2782 	ki->p_xstat = P_WAITSTATUS(p);
2783 	ki->p_acflag = p->p_acflag;
2784 
2785 	strncpy(ki->p_comm, p->p_comm,
2786 	    uimin(sizeof(ki->p_comm), sizeof(p->p_comm)));
2787 	strncpy(ki->p_ename, p->p_emul->e_name, sizeof(ki->p_ename));
2788 
2789 	ki->p_nlwps = p->p_nlwps;
2790 	ki->p_realflag = ki->p_flag;
2791 
2792 	if (p->p_stat != SIDL && !P_ZOMBIE(p) && !zombie) {
2793 		vm = p->p_vmspace;
2794 		ki->p_vm_rssize = vm_resident_count(vm);
2795 		ki->p_vm_tsize = vm->vm_tsize;
2796 		ki->p_vm_dsize = vm->vm_dsize;
2797 		ki->p_vm_ssize = vm->vm_ssize;
2798 		ki->p_vm_vsize = atop(vm->vm_map.size);
2799 		/*
2800 		 * Since the stack is initially mapped mostly with
2801 		 * PROT_NONE and grown as needed, adjust the "mapped size"
2802 		 * to skip the unused stack portion.
2803 		 */
2804 		ki->p_vm_msize =
2805 		    atop(vm->vm_map.size) - vm->vm_issize + vm->vm_ssize;
2806 
2807 		/* Pick the primary (first) LWP */
2808 		l = proc_active_lwp(p);
2809 		KASSERT(l != NULL);
2810 		lwp_lock(l);
2811 		ki->p_nrlwps = p->p_nrlwps;
2812 		ki->p_forw = 0;
2813 		ki->p_back = 0;
2814 		COND_SET_VALUE(ki->p_addr, PTRTOUINT64(l->l_addr), allowaddr);
2815 		ki->p_stat = l->l_stat;
2816 		ki->p_flag |= sysctl_map_flags(sysctl_lwpflagmap, l->l_flag);
2817 		ki->p_swtime = l->l_swtime;
2818 		ki->p_slptime = l->l_slptime;
2819 		if (l->l_stat == LSONPROC)
2820 			ki->p_schedflags = l->l_cpu->ci_schedstate.spc_flags;
2821 		else
2822 			ki->p_schedflags = 0;
2823 		ki->p_priority = lwp_eprio(l);
2824 		ki->p_usrpri = l->l_priority;
2825 		if (l->l_wchan)
2826 			strncpy(ki->p_wmesg, l->l_wmesg, sizeof(ki->p_wmesg));
2827 		COND_SET_VALUE(ki->p_wchan, PTRTOUINT64(l->l_wchan), allowaddr);
2828 		ki->p_cpuid = cpu_index(l->l_cpu);
2829 		lwp_unlock(l);
2830 		LIST_FOREACH(l, &p->p_lwps, l_sibling) {
2831 			/* This is hardly correct, but... */
2832 			sigplusset(&l->l_sigpend.sp_set, &ss1);
2833 			sigplusset(&l->l_sigmask, &ss2);
2834 			ki->p_cpticks += l->l_cpticks;
2835 			ki->p_pctcpu += l->l_pctcpu;
2836 			ki->p_estcpu += l->l_estcpu;
2837 		}
2838 	}
2839 	sigplusset(&p->p_sigpend.sp_set, &ss1);
2840 	memcpy(&ki->p_siglist, &ss1, sizeof(ki_sigset_t));
2841 	memcpy(&ki->p_sigmask, &ss2, sizeof(ki_sigset_t));
2842 
2843 	if (p->p_session != NULL) {
2844 		ki->p_sid = p->p_session->s_sid;
2845 		ki->p__pgid = p->p_pgrp->pg_id;
2846 		if (p->p_session->s_ttyvp)
2847 			ki->p_eflag |= EPROC_CTTY;
2848 		if (SESS_LEADER(p))
2849 			ki->p_eflag |= EPROC_SLEADER;
2850 		strncpy(ki->p_login, p->p_session->s_login,
2851 		    uimin(sizeof ki->p_login - 1, sizeof p->p_session->s_login));
2852 		ki->p_jobc = p->p_pgrp->pg_jobc;
2853 		if ((p->p_lflag & PL_CONTROLT) && (tp = p->p_session->s_ttyp)) {
2854 			ki->p_tdev = tp->t_dev;
2855 			ki->p_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PGID;
2856 			COND_SET_VALUE(ki->p_tsess, PTRTOUINT64(tp->t_session),
2857 			    allowaddr);
2858 		} else {
2859 			ki->p_tdev = (int32_t)NODEV;
2860 		}
2861 	}
2862 
2863 	if (!P_ZOMBIE(p) && !zombie) {
2864 		ki->p_uvalid = 1;
2865 		ki->p_ustart_sec = p->p_stats->p_start.tv_sec;
2866 		ki->p_ustart_usec = p->p_stats->p_start.tv_usec;
2867 
2868 		calcru(p, &ut, &st, NULL, &rt);
2869 		ki->p_rtime_sec = rt.tv_sec;
2870 		ki->p_rtime_usec = rt.tv_usec;
2871 		ki->p_uutime_sec = ut.tv_sec;
2872 		ki->p_uutime_usec = ut.tv_usec;
2873 		ki->p_ustime_sec = st.tv_sec;
2874 		ki->p_ustime_usec = st.tv_usec;
2875 
2876 		memcpy(&ru, &p->p_stats->p_ru, sizeof(ru));
2877 		ki->p_uru_nvcsw = 0;
2878 		ki->p_uru_nivcsw = 0;
2879 		LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
2880 			ki->p_uru_nvcsw += (l2->l_ncsw - l2->l_nivcsw);
2881 			ki->p_uru_nivcsw += l2->l_nivcsw;
2882 			ruadd(&ru, &l2->l_ru);
2883 		}
2884 		ki->p_uru_maxrss = ru.ru_maxrss;
2885 		ki->p_uru_ixrss = ru.ru_ixrss;
2886 		ki->p_uru_idrss = ru.ru_idrss;
2887 		ki->p_uru_isrss = ru.ru_isrss;
2888 		ki->p_uru_minflt = ru.ru_minflt;
2889 		ki->p_uru_majflt = ru.ru_majflt;
2890 		ki->p_uru_nswap = ru.ru_nswap;
2891 		ki->p_uru_inblock = ru.ru_inblock;
2892 		ki->p_uru_oublock = ru.ru_oublock;
2893 		ki->p_uru_msgsnd = ru.ru_msgsnd;
2894 		ki->p_uru_msgrcv = ru.ru_msgrcv;
2895 		ki->p_uru_nsignals = ru.ru_nsignals;
2896 
2897 		timeradd(&p->p_stats->p_cru.ru_utime,
2898 			 &p->p_stats->p_cru.ru_stime, &ut);
2899 		ki->p_uctime_sec = ut.tv_sec;
2900 		ki->p_uctime_usec = ut.tv_usec;
2901 	}
2902 }
2903 
2904 
2905 int
2906 proc_find_locked(struct lwp *l, struct proc **p, pid_t pid)
2907 {
2908 	int error;
2909 
2910 	mutex_enter(&proc_lock);
2911 	if (pid == -1)
2912 		*p = l->l_proc;
2913 	else
2914 		*p = proc_find(pid);
2915 
2916 	if (*p == NULL) {
2917 		if (pid != -1)
2918 			mutex_exit(&proc_lock);
2919 		return ESRCH;
2920 	}
2921 	if (pid != -1)
2922 		mutex_enter((*p)->p_lock);
2923 	mutex_exit(&proc_lock);
2924 
2925 	error = kauth_authorize_process(l->l_cred,
2926 	    KAUTH_PROCESS_CANSEE, *p,
2927 	    KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
2928 	if (error) {
2929 		if (pid != -1)
2930 			mutex_exit((*p)->p_lock);
2931 	}
2932 	return error;
2933 }
2934 
2935 static int
2936 fill_pathname(struct lwp *l, pid_t pid, void *oldp, size_t *oldlenp)
2937 {
2938 	int error;
2939 	struct proc *p;
2940 
2941 	if ((error = proc_find_locked(l, &p, pid)) != 0)
2942 		return error;
2943 
2944 	if (p->p_path == NULL) {
2945 		if (pid != -1)
2946 			mutex_exit(p->p_lock);
2947 		return ENOENT;
2948 	}
2949 
2950 	size_t len = strlen(p->p_path) + 1;
2951 	if (oldp != NULL) {
2952 		size_t copylen = uimin(len, *oldlenp);
2953 		error = sysctl_copyout(l, p->p_path, oldp, copylen);
2954 		if (error == 0 && *oldlenp < len)
2955 			error = ENOSPC;
2956 	}
2957 	*oldlenp = len;
2958 	if (pid != -1)
2959 		mutex_exit(p->p_lock);
2960 	return error;
2961 }
2962 
2963 static int
2964 fill_cwd(struct lwp *l, pid_t pid, void *oldp, size_t *oldlenp)
2965 {
2966 	int error;
2967 	struct proc *p;
2968 	char *path;
2969 	char *bp, *bend;
2970 	struct cwdinfo *cwdi;
2971 	struct vnode *vp;
2972 	size_t len, lenused;
2973 
2974 	if ((error = proc_find_locked(l, &p, pid)) != 0)
2975 		return error;
2976 
2977 	len = MAXPATHLEN * 4;
2978 
2979 	path = kmem_alloc(len, KM_SLEEP);
2980 
2981 	bp = &path[len];
2982 	bend = bp;
2983 	*(--bp) = '\0';
2984 
2985 	cwdi = p->p_cwdi;
2986 	rw_enter(&cwdi->cwdi_lock, RW_READER);
2987 	vp = cwdi->cwdi_cdir;
2988 	error = getcwd_common(vp, NULL, &bp, path, len/2, 0, l);
2989 	rw_exit(&cwdi->cwdi_lock);
2990 
2991 	if (error)
2992 		goto out;
2993 
2994 	lenused = bend - bp;
2995 
2996 	if (oldp != NULL) {
2997 		size_t copylen = uimin(lenused, *oldlenp);
2998 		error = sysctl_copyout(l, bp, oldp, copylen);
2999 		if (error == 0 && *oldlenp < lenused)
3000 			error = ENOSPC;
3001 	}
3002 	*oldlenp = lenused;
3003 out:
3004 	if (pid != -1)
3005 		mutex_exit(p->p_lock);
3006 	kmem_free(path, len);
3007 	return error;
3008 }
3009 
3010 int
3011 proc_getauxv(struct proc *p, void **buf, size_t *len)
3012 {
3013 	struct ps_strings pss;
3014 	int error;
3015 	void *uauxv, *kauxv;
3016 	size_t size;
3017 
3018 	if ((error = copyin_psstrings(p, &pss)) != 0)
3019 		return error;
3020 	if (pss.ps_envstr == NULL)
3021 		return EIO;
3022 
3023 	size = p->p_execsw->es_arglen;
3024 	if (size == 0)
3025 		return EIO;
3026 
3027 	size_t ptrsz = PROC_PTRSZ(p);
3028 	uauxv = (void *)((char *)pss.ps_envstr + (pss.ps_nenvstr + 1) * ptrsz);
3029 
3030 	kauxv = kmem_alloc(size, KM_SLEEP);
3031 
3032 	error = copyin_proc(p, uauxv, kauxv, size);
3033 	if (error) {
3034 		kmem_free(kauxv, size);
3035 		return error;
3036 	}
3037 
3038 	*buf = kauxv;
3039 	*len = size;
3040 
3041 	return 0;
3042 }
3043 
3044 
3045 static int
3046 sysctl_security_expose_address(SYSCTLFN_ARGS)
3047 {
3048 	int expose_address, error;
3049 	struct sysctlnode node;
3050 
3051 	node = *rnode;
3052 	node.sysctl_data = &expose_address;
3053 	expose_address = *(int *)rnode->sysctl_data;
3054 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
3055 	if (error || newp == NULL)
3056 		return error;
3057 
3058 	if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_KERNADDR,
3059 	    0, NULL, NULL, NULL))
3060 		return EPERM;
3061 
3062 	switch (expose_address) {
3063 	case 0:
3064 	case 1:
3065 	case 2:
3066 		break;
3067 	default:
3068 		return EINVAL;
3069 	}
3070 
3071 	*(int *)rnode->sysctl_data = expose_address;
3072 
3073 	return 0;
3074 }
3075 
3076 bool
3077 get_expose_address(struct proc *p)
3078 {
3079 	/* allow only if sysctl variable is set or privileged */
3080 	return kauth_authorize_process(kauth_cred_get(), KAUTH_PROCESS_CANSEE,
3081 	    p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_KPTR), NULL, NULL) == 0;
3082 }
3083