kernel - Major signal path adjustments to fix races, tsleep race fixes, +more
[dragonfly.git] / sys / vfs / procfs / procfs_vnops.c
CommitLineData
984263bc
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1/*
2 * Copyright (c) 1993, 1995 Jan-Simon Pendry
3 * Copyright (c) 1993, 1995
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Jan-Simon Pendry.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed by the University of
20 * California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)procfs_vnops.c 8.18 (Berkeley) 5/21/95
38 *
39 * $FreeBSD: src/sys/miscfs/procfs/procfs_vnops.c,v 1.76.2.7 2002/01/22 17:22:59 nectar Exp $
40 */
41
42/*
43 * procfs vnode interface
44 */
45
46#include <sys/param.h>
47#include <sys/systm.h>
48#include <sys/time.h>
49#include <sys/kernel.h>
50#include <sys/lock.h>
51#include <sys/fcntl.h>
52#include <sys/proc.h>
895c1f85 53#include <sys/priv.h>
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54#include <sys/signalvar.h>
55#include <sys/vnode.h>
56#include <sys/uio.h>
57#include <sys/mount.h>
58#include <sys/namei.h>
59#include <sys/dirent.h>
60#include <sys/malloc.h>
527fddf7 61#include <sys/reg.h>
984263bc 62#include <vm/vm_zone.h>
1f2de5d4 63#include <vfs/procfs/procfs.h>
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64#include <sys/pioctl.h>
65
e193508c
MD
66#include <sys/spinlock2.h>
67
dcab9ef0
JS
68#include <machine/limits.h>
69
a6ee311a 70static int procfs_access (struct vop_access_args *);
66a1ddf5 71static int procfs_badop (struct vop_generic_args *);
a6ee311a
RG
72static int procfs_bmap (struct vop_bmap_args *);
73static int procfs_close (struct vop_close_args *);
74static int procfs_getattr (struct vop_getattr_args *);
75static int procfs_inactive (struct vop_inactive_args *);
76static int procfs_ioctl (struct vop_ioctl_args *);
e62afb5f 77static int procfs_lookup (struct vop_old_lookup_args *);
a6ee311a
RG
78static int procfs_open (struct vop_open_args *);
79static int procfs_print (struct vop_print_args *);
80static int procfs_readdir (struct vop_readdir_args *);
81static int procfs_readlink (struct vop_readlink_args *);
82static int procfs_reclaim (struct vop_reclaim_args *);
83static int procfs_setattr (struct vop_setattr_args *);
984263bc 84
dcab9ef0
JS
85static int procfs_readdir_proc(struct vop_readdir_args *);
86static int procfs_readdir_root(struct vop_readdir_args *);
87
984263bc 88/*
66a1ddf5
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89 * procfs vnode operations.
90 */
91struct vop_ops procfs_vnode_vops = {
92 .vop_default = vop_defaultop,
93 .vop_access = procfs_access,
94 .vop_advlock = (void *)procfs_badop,
95 .vop_bmap = procfs_bmap,
96 .vop_close = procfs_close,
97 .vop_old_create = (void *)procfs_badop,
98 .vop_getattr = procfs_getattr,
99 .vop_inactive = procfs_inactive,
100 .vop_old_link = (void *)procfs_badop,
101 .vop_old_lookup = procfs_lookup,
102 .vop_old_mkdir = (void *)procfs_badop,
103 .vop_old_mknod = (void *)procfs_badop,
104 .vop_open = procfs_open,
105 .vop_pathconf = vop_stdpathconf,
106 .vop_print = procfs_print,
107 .vop_read = procfs_rw,
108 .vop_readdir = procfs_readdir,
109 .vop_readlink = procfs_readlink,
110 .vop_reclaim = procfs_reclaim,
111 .vop_old_remove = (void *)procfs_badop,
112 .vop_old_rename = (void *)procfs_badop,
113 .vop_old_rmdir = (void *)procfs_badop,
114 .vop_setattr = procfs_setattr,
115 .vop_old_symlink = (void *)procfs_badop,
116 .vop_write = (void *)procfs_rw,
117 .vop_ioctl = procfs_ioctl
118};
119
120
121/*
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MD
122 * This is a list of the valid names in the
123 * process-specific sub-directories. It is
124 * used in procfs_lookup and procfs_readdir
125 */
126static struct proc_target {
127 u_char pt_type;
128 u_char pt_namlen;
129 char *pt_name;
130 pfstype pt_pfstype;
c7e98b2f 131 int (*pt_valid) (struct lwp *p);
984263bc
MD
132} proc_targets[] = {
133#define N(s) sizeof(s)-1, s
134 /* name type validp */
135 { DT_DIR, N("."), Pproc, NULL },
136 { DT_DIR, N(".."), Proot, NULL },
137 { DT_REG, N("mem"), Pmem, NULL },
138 { DT_REG, N("regs"), Pregs, procfs_validregs },
139 { DT_REG, N("fpregs"), Pfpregs, procfs_validfpregs },
140 { DT_REG, N("dbregs"), Pdbregs, procfs_validdbregs },
141 { DT_REG, N("ctl"), Pctl, NULL },
142 { DT_REG, N("status"), Pstatus, NULL },
143 { DT_REG, N("note"), Pnote, NULL },
144 { DT_REG, N("notepg"), Pnotepg, NULL },
145 { DT_REG, N("map"), Pmap, procfs_validmap },
146 { DT_REG, N("etype"), Ptype, procfs_validtype },
147 { DT_REG, N("cmdline"), Pcmdline, NULL },
148 { DT_REG, N("rlimit"), Prlimit, NULL },
149 { DT_LNK, N("file"), Pfile, NULL },
150#undef N
151};
c157ff7a 152static const int nproc_targets = NELEM(proc_targets);
984263bc 153
a6ee311a 154static pid_t atopid (const char *, u_int);
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155
156/*
157 * set things up for doing i/o on
158 * the pfsnode (vp). (vp) is locked
159 * on entry, and should be left locked
160 * on exit.
161 *
162 * for procfs we don't need to do anything
163 * in particular for i/o. all that is done
164 * is to support exclusive open on process
165 * memory images.
ac424f9b 166 *
b478fdce
SW
167 * procfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred,
168 * struct file *a_fp)
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169 */
170static int
ac424f9b 171procfs_open(struct vop_open_args *ap)
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172{
173 struct pfsnode *pfs = VTOPFS(ap->a_vp);
174 struct proc *p1, *p2;
58c2553a 175 int error;
984263bc 176
198c0ff2 177 p2 = pfs_pfind(pfs->pfs_pid);
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178 if (p2 == NULL)
179 return (ENOENT);
58c2553a
MD
180 if (pfs->pfs_pid && !PRISON_CHECK(ap->a_cred, p2->p_ucred)) {
181 error = ENOENT;
182 goto done;
183 }
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184
185 switch (pfs->pfs_type) {
186 case Pmem:
187 if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) ||
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MD
188 ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE))) {
189 error = EBUSY;
190 goto done;
191 }
984263bc 192
87de5057 193 p1 = curproc;
dadab5e9 194 KKASSERT(p1);
984263bc 195 /* Can't trace a process that's currently exec'ing. */
4643740a 196 if ((p2->p_flags & P_INEXEC) != 0) {
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MD
197 error = EAGAIN;
198 goto done;
199 }
200 if (!CHECKIO(p1, p2) || p_trespass(ap->a_cred, p2->p_ucred)) {
201 error = EPERM;
202 goto done;
203 }
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204
205 if (ap->a_mode & FWRITE)
206 pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL);
207
8ddc6004 208 break;
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209
210 default:
211 break;
212 }
58c2553a
MD
213 error = vop_stdopen(ap);
214done:
215 PRELE(p2);
216 return error;
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217}
218
219/*
220 * close the pfsnode (vp) after doing i/o.
221 * (vp) is not locked on entry or exit.
222 *
223 * nothing to do for procfs other than undo
224 * any exclusive open flag (see _open above).
ac424f9b 225 *
87de5057 226 * procfs_close(struct vnode *a_vp, int a_fflag, struct ucred *a_cred)
984263bc
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227 */
228static int
ac424f9b 229procfs_close(struct vop_close_args *ap)
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230{
231 struct pfsnode *pfs = VTOPFS(ap->a_vp);
232 struct proc *p;
233
234 switch (pfs->pfs_type) {
235 case Pmem:
236 if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL))
237 pfs->pfs_flags &= ~(FWRITE|O_EXCL);
238 /*
3c37c940
MD
239 * v_opencount determines the last real close on the vnode.
240 *
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MD
241 * If this is the last close, then it checks to see if
242 * the target process has PF_LINGER set in p_pfsflags,
243 * if this is *not* the case, then the process' stop flags
244 * are cleared, and the process is woken up. This is
245 * to help prevent the case where a process has been
246 * told to stop on an event, but then the requesting process
247 * has gone away or forgotten about it.
248 */
58c2553a 249 p = NULL;
3c37c940 250 if ((ap->a_vp->v_opencount < 2)
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251 && (p = pfind(pfs->pfs_pid))
252 && !(p->p_pfsflags & PF_LINGER)) {
287a8577 253 spin_lock(&p->p_spin);
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254 p->p_stops = 0;
255 p->p_step = 0;
287a8577 256 spin_unlock(&p->p_spin);
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257 wakeup(&p->p_step);
258 }
58c2553a
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259 if (p)
260 PRELE(p);
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261 break;
262 default:
263 break;
264 }
265
8ddc6004 266 return (vop_stdclose(ap));
984263bc
MD
267}
268
269/*
270 * do an ioctl operation on a pfsnode (vp).
271 * (vp) is not locked on entry or exit.
272 */
273static int
ac424f9b 274procfs_ioctl(struct vop_ioctl_args *ap)
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275{
276 struct pfsnode *pfs = VTOPFS(ap->a_vp);
dadab5e9
MD
277 struct proc *procp;
278 struct proc *p;
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279 int error;
280 int signo;
281 struct procfs_status *psp;
282 unsigned char flags;
283
984263bc 284 procp = pfind(pfs->pfs_pid);
dadab5e9 285 if (procp == NULL)
984263bc 286 return ENOTTY;
87de5057 287 p = curproc;
58c2553a
MD
288 if (p == NULL) {
289 error = EINVAL;
290 goto done;
291 }
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MD
292
293 /* Can't trace a process that's currently exec'ing. */
4643740a 294 if ((procp->p_flags & P_INEXEC) != 0) {
58c2553a
MD
295 error = EAGAIN;
296 goto done;
297 }
298 if (!CHECKIO(p, procp) || p_trespass(ap->a_cred, procp->p_ucred)) {
299 error = EPERM;
300 goto done;
301 }
984263bc
MD
302
303 switch (ap->a_command) {
304 case PIOCBIS:
305 procp->p_stops |= *(unsigned int*)ap->a_data;
306 break;
307 case PIOCBIC:
308 procp->p_stops &= ~*(unsigned int*)ap->a_data;
309 break;
310 case PIOCSFL:
311 /*
312 * NFLAGS is "non-suser_xxx flags" -- currently, only
313 * PFS_ISUGID ("ignore set u/g id");
314 */
315#define NFLAGS (PF_ISUGID)
316 flags = (unsigned char)*(unsigned int*)ap->a_data;
895c1f85 317 if (flags & NFLAGS && (error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0)))
58c2553a 318 goto done;
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MD
319 procp->p_pfsflags = flags;
320 break;
321 case PIOCGFL:
322 *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags;
323 break;
324 case PIOCSTATUS:
e193508c
MD
325 /*
326 * NOTE: syscall entry deals with stopevents and may run without
327 * the MP lock.
328 */
984263bc 329 psp = (struct procfs_status *)ap->a_data;
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MD
330 psp->flags = procp->p_pfsflags;
331 psp->events = procp->p_stops;
287a8577 332 spin_lock(&procp->p_spin);
984263bc 333 if (procp->p_step) {
e193508c 334 psp->state = 0;
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MD
335 psp->why = procp->p_stype;
336 psp->val = procp->p_xstat;
287a8577 337 spin_unlock(&procp->p_spin);
984263bc 338 } else {
e193508c 339 psp->state = 1;
287a8577 340 spin_unlock(&procp->p_spin);
e193508c
MD
341 psp->why = 0; /* Not defined values */
342 psp->val = 0; /* Not defined values */
984263bc
MD
343 }
344 break;
345 case PIOCWAIT:
e193508c
MD
346 /*
347 * NOTE: syscall entry deals with stopevents and may run without
348 * the MP lock.
349 */
984263bc 350 psp = (struct procfs_status *)ap->a_data;
287a8577 351 spin_lock(&procp->p_spin);
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MD
352 while (procp->p_step == 0) {
353 tsleep_interlock(&procp->p_stype, PCATCH);
287a8577 354 spin_unlock(&procp->p_spin);
e193508c 355 error = tsleep(&procp->p_stype, PCATCH | PINTERLOCKED, "piocwait", 0);
984263bc 356 if (error)
58c2553a 357 goto done;
287a8577 358 spin_lock(&procp->p_spin);
984263bc 359 }
287a8577 360 spin_unlock(&procp->p_spin);
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MD
361 psp->state = 1; /* It stopped */
362 psp->flags = procp->p_pfsflags;
363 psp->events = procp->p_stops;
364 psp->why = procp->p_stype; /* why it stopped */
365 psp->val = procp->p_xstat; /* any extra info */
366 break;
367 case PIOCCONT: /* Restart a proc */
e193508c
MD
368 /*
369 * NOTE: syscall entry deals with stopevents and may run without
370 * the MP lock. However, the caller is presumably interlocked
371 * by having waited.
372 */
58c2553a
MD
373 if (procp->p_step == 0) {
374 error = EINVAL; /* Can only start a stopped process */
375 goto done;
376 }
984263bc 377 if ((signo = *(int*)ap->a_data) != 0) {
58c2553a
MD
378 if (signo >= NSIG || signo <= 0) {
379 error = EINVAL;
380 goto done;
381 }
84204577 382 ksignal(procp, signo);
984263bc
MD
383 }
384 procp->p_step = 0;
385 wakeup(&procp->p_step);
386 break;
387 default:
58c2553a
MD
388 error = ENOTTY;
389 goto done;
984263bc 390 }
58c2553a
MD
391 error = 0;
392done:
393 PRELE(procp);
984263bc
MD
394 return 0;
395}
396
397/*
398 * do block mapping for pfsnode (vp).
399 * since we don't use the buffer cache
400 * for procfs this function should never
401 * be called. in any case, it's not clear
402 * what part of the kernel ever makes use
403 * of this function. for sanity, this is the
404 * usual no-op bmap, although returning
405 * (EIO) would be a reasonable alternative.
ac424f9b 406 *
08daea96
MD
407 * XXX mmap assumes buffer cache operation
408 *
409 * procfs_bmap(struct vnode *a_vp, off_t a_loffset,
410 * off_t *a_doffsetp, int *a_runp, int *a_runb)
984263bc
MD
411 */
412static int
ac424f9b 413procfs_bmap(struct vop_bmap_args *ap)
984263bc 414{
54078292
MD
415 if (ap->a_doffsetp != NULL)
416 *ap->a_doffsetp = ap->a_loffset;
984263bc
MD
417 if (ap->a_runp != NULL)
418 *ap->a_runp = 0;
54078292
MD
419 if (ap->a_runb != NULL)
420 *ap->a_runb = 0;
984263bc
MD
421 return (0);
422}
423
424/*
425 * procfs_inactive is called when the pfsnode
426 * is vrele'd and the reference count goes
427 * to zero. (vp) will be on the vnode free
428 * list, so to get it back vget() must be
429 * used.
430 *
431 * (vp) is locked on entry, but must be unlocked on exit.
ac424f9b 432 *
b478fdce 433 * procfs_inactive(struct vnode *a_vp)
984263bc
MD
434 */
435static int
ac424f9b 436procfs_inactive(struct vop_inactive_args *ap)
984263bc 437{
e193508c 438 struct pfsnode *pfs = VTOPFS(ap->a_vp);
984263bc 439
e193508c
MD
440 if (pfs->pfs_pid & PFS_DEAD)
441 vrecycle(ap->a_vp);
984263bc
MD
442 return (0);
443}
444
445/*
446 * _reclaim is called when getnewvnode()
447 * wants to make use of an entry on the vnode
448 * free list. at this time the filesystem needs
449 * to free any private data and remove the node
450 * from any private lists.
ac424f9b
CP
451 *
452 * procfs_reclaim(struct vnode *a_vp)
984263bc
MD
453 */
454static int
ac424f9b 455procfs_reclaim(struct vop_reclaim_args *ap)
984263bc 456{
984263bc
MD
457 return (procfs_freevp(ap->a_vp));
458}
459
460/*
461 * _print is used for debugging.
462 * just print a readable description
463 * of (vp).
ac424f9b
CP
464 *
465 * procfs_print(struct vnode *a_vp)
984263bc
MD
466 */
467static int
ac424f9b 468procfs_print(struct vop_print_args *ap)
984263bc
MD
469{
470 struct pfsnode *pfs = VTOPFS(ap->a_vp);
471
086c1d7e 472 kprintf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n",
984263bc
MD
473 pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags);
474 return (0);
475}
476
477/*
478 * generic entry point for unsupported operations
479 */
480static int
66a1ddf5 481procfs_badop(struct vop_generic_args *ap)
984263bc 482{
984263bc
MD
483 return (EIO);
484}
485
486/*
487 * Invent attributes for pfsnode (vp) and store
488 * them in (vap).
489 * Directories lengths are returned as zero since
490 * any real length would require the genuine size
491 * to be computed, and nothing cares anyway.
492 *
493 * this is relatively minimal for procfs.
ac424f9b 494 *
b478fdce 495 * procfs_getattr(struct vnode *a_vp, struct vattr *a_vap)
984263bc
MD
496 */
497static int
ac424f9b 498procfs_getattr(struct vop_getattr_args *ap)
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MD
499{
500 struct pfsnode *pfs = VTOPFS(ap->a_vp);
501 struct vattr *vap = ap->a_vap;
502 struct proc *procp;
503 int error;
504
505 /*
506 * First make sure that the process and its credentials
507 * still exist.
508 */
509 switch (pfs->pfs_type) {
510 case Proot:
511 case Pcurproc:
58c2553a 512 procp = NULL;
984263bc
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513 break;
514
515 default:
198c0ff2 516 procp = pfs_pfind(pfs->pfs_pid);
58c2553a
MD
517 if (procp == NULL || procp->p_ucred == NULL) {
518 error = ENOENT;
519 goto done;
520 }
984263bc
MD
521 }
522
523 error = 0;
524
525 /* start by zeroing out the attributes */
526 VATTR_NULL(vap);
527
528 /* next do all the common fields */
529 vap->va_type = ap->a_vp->v_type;
530 vap->va_mode = pfs->pfs_mode;
531 vap->va_fileid = pfs->pfs_fileno;
532 vap->va_flags = 0;
533 vap->va_blocksize = PAGE_SIZE;
534 vap->va_bytes = vap->va_size = 0;
535 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0];
536
537 /*
538 * Make all times be current TOD.
539 * It would be possible to get the process start
540 * time from the p_stat structure, but there's
541 * no "file creation" time stamp anyway, and the
542 * p_stat structure is not addressible if u. gets
543 * swapped out for that process.
544 */
545 nanotime(&vap->va_ctime);
546 vap->va_atime = vap->va_mtime = vap->va_ctime;
547
548 /*
549 * If the process has exercised some setuid or setgid
550 * privilege, then rip away read/write permission so
551 * that only root can gain access.
552 */
553 switch (pfs->pfs_type) {
554 case Pctl:
555 case Pregs:
556 case Pfpregs:
557 case Pdbregs:
558 case Pmem:
4643740a 559 if (procp->p_flags & P_SUGID)
984263bc
MD
560 vap->va_mode &= ~((VREAD|VWRITE)|
561 ((VREAD|VWRITE)>>3)|
562 ((VREAD|VWRITE)>>6));
563 break;
564 default:
565 break;
566 }
567
568 /*
569 * now do the object specific fields
570 *
571 * The size could be set from struct reg, but it's hardly
572 * worth the trouble, and it puts some (potentially) machine
573 * dependent data into this machine-independent code. If it
574 * becomes important then this function should break out into
575 * a per-file stat function in the corresponding .c file.
576 */
577
578 vap->va_nlink = 1;
579 if (procp) {
580 vap->va_uid = procp->p_ucred->cr_uid;
581 vap->va_gid = procp->p_ucred->cr_gid;
582 }
583
584 switch (pfs->pfs_type) {
585 case Proot:
586 /*
587 * Set nlink to 1 to tell fts(3) we don't actually know.
588 */
589 vap->va_nlink = 1;
590 vap->va_uid = 0;
591 vap->va_gid = 0;
592 vap->va_size = vap->va_bytes = DEV_BSIZE;
593 break;
594
595 case Pcurproc: {
596 char buf[16]; /* should be enough */
597 vap->va_uid = 0;
598 vap->va_gid = 0;
599 vap->va_size = vap->va_bytes =
f8c7a42d 600 ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid);
984263bc
MD
601 break;
602 }
603
604 case Pproc:
605 vap->va_nlink = nproc_targets;
606 vap->va_size = vap->va_bytes = DEV_BSIZE;
607 break;
608
609 case Pfile: {
610 char *fullpath, *freepath;
5b4cfb7e 611 error = cache_fullpath(procp, &procp->p_textnch, &fullpath, &freepath, 0);
984263bc
MD
612 if (error == 0) {
613 vap->va_size = strlen(fullpath);
efda3bd0 614 kfree(freepath, M_TEMP);
984263bc
MD
615 } else {
616 vap->va_size = sizeof("unknown") - 1;
617 error = 0;
618 }
619 vap->va_bytes = vap->va_size;
620 break;
621 }
622
623 case Pmem:
624 /*
625 * If we denied owner access earlier, then we have to
626 * change the owner to root - otherwise 'ps' and friends
627 * will break even though they are setgid kmem. *SIGH*
628 */
4643740a 629 if (procp->p_flags & P_SUGID)
984263bc
MD
630 vap->va_uid = 0;
631 else
632 vap->va_uid = procp->p_ucred->cr_uid;
633 break;
634
635 case Pregs:
636 vap->va_bytes = vap->va_size = sizeof(struct reg);
637 break;
638
639 case Pfpregs:
640 vap->va_bytes = vap->va_size = sizeof(struct fpreg);
641 break;
642
643 case Pdbregs:
644 vap->va_bytes = vap->va_size = sizeof(struct dbreg);
645 break;
646
647 case Ptype:
648 case Pmap:
649 case Pctl:
650 case Pstatus:
651 case Pnote:
652 case Pnotepg:
653 case Pcmdline:
654 case Prlimit:
655 break;
656
657 default:
658 panic("procfs_getattr");
659 }
58c2553a
MD
660done:
661 if (procp)
662 PRELE(procp);
984263bc
MD
663 return (error);
664}
665
ac424f9b
CP
666/*
667 * procfs_setattr(struct vnode *a_vp, struct vattr *a_vap,
b478fdce 668 * struct ucred *a_cred)
ac424f9b 669 */
984263bc 670static int
ac424f9b 671procfs_setattr(struct vop_setattr_args *ap)
984263bc 672{
984263bc
MD
673 if (ap->a_vap->va_flags != VNOVAL)
674 return (EOPNOTSUPP);
675
676 /*
677 * just fake out attribute setting
678 * it's not good to generate an error
679 * return, otherwise things like creat()
680 * will fail when they try to set the
681 * file length to 0. worse, this means
682 * that echo $note > /proc/$pid/note will fail.
683 */
684
685 return (0);
686}
687
688/*
689 * implement access checking.
690 *
b478fdce 691 * procfs_access(struct vnode *a_vp, int a_mode, struct ucred *a_cred)
984263bc
MD
692 */
693static int
ac424f9b 694procfs_access(struct vop_access_args *ap)
984263bc 695{
984263bc
MD
696 struct vattr vattr;
697 int error;
698
52cdca9a
NT
699 error = VOP_GETATTR(ap->a_vp, &vattr);
700 if (!error)
701 error = vop_helper_access(ap, vattr.va_uid, vattr.va_gid,
702 vattr.va_mode, 0);
703 return (error);
984263bc
MD
704}
705
706/*
3446c007
MD
707 * lookup. this is incredibly complicated in the general case, however
708 * for most pseudo-filesystems very little needs to be done.
ac424f9b
CP
709 *
710 * procfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp,
711 * struct componentname *a_cnp)
984263bc
MD
712 */
713static int
e62afb5f 714procfs_lookup(struct vop_old_lookup_args *ap)
984263bc
MD
715{
716 struct componentname *cnp = ap->a_cnp;
717 struct vnode **vpp = ap->a_vpp;
718 struct vnode *dvp = ap->a_dvp;
719 char *pname = cnp->cn_nameptr;
720 /* struct proc *curp = cnp->cn_proc; */
721 struct proc_target *pt;
722 pid_t pid;
723 struct pfsnode *pfs;
724 struct proc *p;
c7e98b2f 725 struct lwp *lp;
984263bc 726 int i;
3446c007 727 int error;
984263bc
MD
728
729 *vpp = NULL;
730
2b69e610 731 if (cnp->cn_nameiop == NAMEI_DELETE || cnp->cn_nameiop == NAMEI_RENAME)
984263bc
MD
732 return (EROFS);
733
58c2553a 734 p = NULL;
3446c007 735 error = 0;
984263bc
MD
736 if (cnp->cn_namelen == 1 && *pname == '.') {
737 *vpp = dvp;
3446c007
MD
738 vref(*vpp);
739 goto out;
984263bc
MD
740 }
741
742 pfs = VTOPFS(dvp);
743 switch (pfs->pfs_type) {
744 case Proot:
2b69e610 745 if (cnp->cn_flags & CNP_ISDOTDOT)
984263bc
MD
746 return (EIO);
747
3446c007
MD
748 if (CNEQ(cnp, "curproc", 7)) {
749 error = procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc);
750 goto out;
751 }
984263bc
MD
752
753 pid = atopid(pname, cnp->cn_namelen);
754 if (pid == NO_PID)
755 break;
756
198c0ff2 757 p = pfs_pfind(pid);
984263bc
MD
758 if (p == NULL)
759 break;
760
dcab9ef0
JS
761 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred))
762 break;
763
28c57d20
HP
764 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 &&
765 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid)
766 break;
767
3446c007
MD
768 error = procfs_allocvp(dvp->v_mount, vpp, pid, Pproc);
769 goto out;
984263bc
MD
770
771 case Pproc:
3446c007
MD
772 if (cnp->cn_flags & CNP_ISDOTDOT) {
773 error = procfs_root(dvp->v_mount, vpp);
774 goto out;
775 }
984263bc 776
198c0ff2 777 p = pfs_pfind(pfs->pfs_pid);
984263bc
MD
778 if (p == NULL)
779 break;
c7e98b2f
SS
780 /* XXX lwp */
781 lp = FIRST_LWP_IN_PROC(p);
984263bc 782
dcab9ef0
JS
783 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred))
784 break;
785
28c57d20
HP
786 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 &&
787 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid)
788 break;
789
984263bc
MD
790 for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) {
791 if (cnp->cn_namelen == pt->pt_namlen &&
792 bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 &&
c7e98b2f 793 (pt->pt_valid == NULL || (*pt->pt_valid)(lp)))
984263bc
MD
794 goto found;
795 }
796 break;
797 found:
3446c007
MD
798 error = procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid,
799 pt->pt_pfstype);
800 goto out;
984263bc
MD
801
802 default:
3446c007
MD
803 error = ENOTDIR;
804 goto out;
984263bc 805 }
3446c007
MD
806 if (cnp->cn_nameiop == NAMEI_LOOKUP)
807 error = ENOENT;
808 else
809 error = EROFS;
810 /*
811 * If no error occured *vpp will hold a referenced locked vnode.
aa723195
MD
812 * dvp was passed to us locked and *vpp must be returned locked.
813 * If *vpp != dvp then we should unlock dvp if (1) this is not the
814 * last component or (2) CNP_LOCKPARENT is not set.
3446c007
MD
815 */
816out:
aa723195
MD
817 if (error == 0 && *vpp != dvp) {
818 if ((cnp->cn_flags & CNP_LOCKPARENT) == 0) {
819 cnp->cn_flags |= CNP_PDIRUNLOCK;
a11aaa81 820 vn_unlock(dvp);
3446c007
MD
821 }
822 }
58c2553a
MD
823 if (p)
824 PRELE(p);
3446c007 825 return (error);
984263bc
MD
826}
827
828/*
829 * Does this process have a text file?
830 */
4d4fb029 831int
c7e98b2f 832procfs_validfile(struct lwp *lp)
984263bc 833{
c7e98b2f 834 return (procfs_findtextvp(lp->lwp_proc) != NULLVP);
984263bc
MD
835}
836
837/*
838 * readdir() returns directory entries from pfsnode (vp).
839 *
840 * We generate just one directory entry at a time, as it would probably
841 * not pay off to buffer several entries locally to save uiomove calls.
ac424f9b
CP
842 *
843 * procfs_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred,
84009d92 844 * int *a_eofflag, int *a_ncookies, off_t **a_cookies)
984263bc
MD
845 */
846static int
ac424f9b 847procfs_readdir(struct vop_readdir_args *ap)
984263bc 848{
984263bc 849 struct pfsnode *pfs;
dcab9ef0 850 int error;
984263bc 851
dcab9ef0 852 if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX)
984263bc 853 return (EINVAL);
885ecb13
MD
854 if ((error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY)) != 0)
855 return (error);
dcab9ef0 856 pfs = VTOPFS(ap->a_vp);
984263bc
MD
857
858 switch (pfs->pfs_type) {
dcab9ef0 859 case Pproc:
885ecb13
MD
860 /*
861 * this is for the process-specific sub-directories.
862 * all that is needed to is copy out all the entries
863 * from the procent[] table (top of this file).
864 */
dcab9ef0
JS
865 error = procfs_readdir_proc(ap);
866 break;
dcab9ef0 867 case Proot:
885ecb13
MD
868 /*
869 * this is for the root of the procfs filesystem
870 * what is needed is a special entry for "curproc"
871 * followed by an entry for each process on allproc
872 */
dcab9ef0 873 error = procfs_readdir_root(ap);
984263bc 874 break;
984263bc
MD
875 default:
876 error = ENOTDIR;
877 break;
878 }
879
885ecb13 880 vn_unlock(ap->a_vp);
984263bc
MD
881 return (error);
882}
883
dcab9ef0
JS
884static int
885procfs_readdir_proc(struct vop_readdir_args *ap)
886{
887 struct pfsnode *pfs;
888 int error, i, retval;
889 struct proc *p;
c7e98b2f 890 struct lwp *lp;
dcab9ef0
JS
891 struct proc_target *pt;
892 struct uio *uio = ap->a_uio;
893
894 pfs = VTOPFS(ap->a_vp);
198c0ff2 895 p = pfs_pfind(pfs->pfs_pid);
dcab9ef0
JS
896 if (p == NULL)
897 return(0);
58c2553a
MD
898 if (!PRISON_CHECK(ap->a_cred, p->p_ucred)) {
899 error = 0;
900 goto done;
901 }
902 /* XXX lwp, not MPSAFE */
c7e98b2f 903 lp = FIRST_LWP_IN_PROC(p);
dcab9ef0
JS
904
905 error = 0;
fb0466c9 906 i = (int)uio->uio_offset;
58c2553a
MD
907 if (i < 0) {
908 error = EINVAL;
909 goto done;
910 }
dcab9ef0
JS
911
912 for (pt = &proc_targets[i];
913 !error && uio->uio_resid > 0 && i < nproc_targets; pt++, i++) {
c7e98b2f 914 if (pt->pt_valid && (*pt->pt_valid)(lp) == 0)
dcab9ef0
JS
915 continue;
916
917 retval = vop_write_dirent(&error, uio,
918 PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype), pt->pt_type,
919 pt->pt_namlen, pt->pt_name);
920 if (retval)
921 break;
922 }
923
fb0466c9 924 uio->uio_offset = (off_t)i;
58c2553a
MD
925 error = 0;
926done:
927 PRELE(p);
928 return error;
dcab9ef0
JS
929}
930
51e64ff2
MD
931struct procfs_readdir_root_info {
932 int error;
933 int i;
934 int pcnt;
935 struct uio *uio;
936 struct ucred *cred;
937};
938
939static int procfs_readdir_root_callback(struct proc *p, void *data);
940
dcab9ef0
JS
941static int
942procfs_readdir_root(struct vop_readdir_args *ap)
943{
51e64ff2 944 struct procfs_readdir_root_info info;
dcab9ef0 945 struct uio *uio = ap->a_uio;
51e64ff2
MD
946 int res;
947
948 info.error = 0;
fb0466c9
MD
949 info.i = (int)uio->uio_offset;
950
951 if (info.i < 0)
952 return (EINVAL);
953
51e64ff2
MD
954 info.pcnt = 0;
955 info.uio = uio;
956 info.cred = ap->a_cred;
51e64ff2
MD
957 while (info.pcnt < 3) {
958 res = procfs_readdir_root_callback(NULL, &info);
959 if (res < 0)
960 break;
961 }
962 if (res >= 0)
963 allproc_scan(procfs_readdir_root_callback, &info);
fb0466c9 964 uio->uio_offset = (off_t)info.i;
51e64ff2
MD
965
966 return (info.error);
967}
968
969static int
970procfs_readdir_root_callback(struct proc *p, void *data)
971{
972 struct procfs_readdir_root_info *info = data;
973 struct uio *uio;
974 int retval;
dcab9ef0
JS
975 ino_t d_ino;
976 const char *d_name;
977 char d_name_pid[20];
978 size_t d_namlen;
979 uint8_t d_type;
980
51e64ff2 981 uio = info->uio;
dcab9ef0 982
51e64ff2
MD
983 if (uio->uio_resid <= 0 || info->error)
984 return(-1);
dcab9ef0 985
51e64ff2
MD
986 switch (info->pcnt) {
987 case 0: /* `.' */
988 d_ino = PROCFS_FILENO(0, Proot);
989 d_name = ".";
990 d_namlen = 1;
991 d_type = DT_DIR;
992 break;
993 case 1: /* `..' */
994 d_ino = PROCFS_FILENO(0, Proot);
995 d_name = "..";
996 d_namlen = 2;
997 d_type = DT_DIR;
998 break;
dcab9ef0 999
51e64ff2
MD
1000 case 2:
1001 d_ino = PROCFS_FILENO(0, Pcurproc);
1002 d_namlen = 7;
1003 d_name = "curproc";
1004 d_type = DT_LNK;
1005 break;
dcab9ef0 1006
51e64ff2
MD
1007
1008 default:
1009 if (!PRISON_CHECK(info->cred, p->p_ucred))
1010 return(0);
1011 if (ps_showallprocs == 0 &&
1012 info->cred->cr_uid != 0 &&
1013 info->cred->cr_uid != p->p_ucred->cr_uid) {
1014 return(0);
dcab9ef0
JS
1015 }
1016
51e64ff2
MD
1017 /*
1018 * Skip entries we have already returned (optimization)
1019 */
1020 if (info->pcnt < info->i) {
1021 ++info->pcnt;
1022 return(0);
1023 }
1024
1025 d_ino = PROCFS_FILENO(p->p_pid, Pproc);
f8c7a42d 1026 d_namlen = ksnprintf(d_name_pid, sizeof(d_name_pid),
51e64ff2
MD
1027 "%ld", (long)p->p_pid);
1028 d_name = d_name_pid;
1029 d_type = DT_DIR;
1030 break;
dcab9ef0 1031 }
51e64ff2
MD
1032
1033 /*
1034 * Skip entries we have already returned (optimization)
1035 */
1036 if (info->pcnt < info->i) {
1037 ++info->pcnt;
1038 return(0);
1039 }
1040
1041 retval = vop_write_dirent(&info->error, uio,
1042 d_ino, d_type, d_namlen, d_name);
1043 if (retval)
1044 return(-1);
1045 ++info->pcnt;
1046 ++info->i;
dcab9ef0
JS
1047 return(0);
1048}
1049
984263bc
MD
1050/*
1051 * readlink reads the link of `curproc' or `file'
1052 */
1053static int
ac424f9b 1054procfs_readlink(struct vop_readlink_args *ap)
984263bc
MD
1055{
1056 char buf[16]; /* should be enough */
1057 struct proc *procp;
1058 struct vnode *vp = ap->a_vp;
1059 struct pfsnode *pfs = VTOPFS(vp);
1060 char *fullpath, *freepath;
1061 int error, len;
1062
1063 switch (pfs->pfs_type) {
1064 case Pcurproc:
1065 if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc))
1066 return (EINVAL);
1067
f8c7a42d 1068 len = ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid);
984263bc
MD
1069
1070 return (uiomove(buf, len, ap->a_uio));
1071 /*
1072 * There _should_ be no way for an entire process to disappear
1073 * from under us...
1074 */
1075 case Pfile:
198c0ff2 1076 procp = pfs_pfind(pfs->pfs_pid);
41c20dac 1077 if (procp == NULL || procp->p_ucred == NULL) {
086c1d7e 1078 kprintf("procfs_readlink: pid %d disappeared\n",
984263bc 1079 pfs->pfs_pid);
58c2553a
MD
1080 if (procp)
1081 PRELE(procp);
984263bc
MD
1082 return (uiomove("unknown", sizeof("unknown") - 1,
1083 ap->a_uio));
1084 }
5b4cfb7e 1085 error = cache_fullpath(procp, &procp->p_textnch, &fullpath, &freepath, 0);
58c2553a
MD
1086 if (error != 0) {
1087 if (procp)
1088 PRELE(procp);
984263bc
MD
1089 return (uiomove("unknown", sizeof("unknown") - 1,
1090 ap->a_uio));
58c2553a 1091 }
984263bc 1092 error = uiomove(fullpath, strlen(fullpath), ap->a_uio);
efda3bd0 1093 kfree(freepath, M_TEMP);
58c2553a
MD
1094 if (procp)
1095 PRELE(procp);
984263bc
MD
1096 return (error);
1097 default:
1098 return (EINVAL);
1099 }
1100}
1101
1102/*
1103 * convert decimal ascii to pid_t
1104 */
1105static pid_t
ac424f9b 1106atopid(const char *b, u_int len)
984263bc
MD
1107{
1108 pid_t p = 0;
1109
1110 while (len--) {
1111 char c = *b++;
1112 if (c < '0' || c > '9')
1113 return (NO_PID);
1114 p = 10 * p + (c - '0');
1115 if (p > PID_MAX)
1116 return (NO_PID);
1117 }
1118
1119 return (p);
1120}
1121