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kern_ktrace.c revision 1.46.2.1
      1 /*	$NetBSD: kern_ktrace.c,v 1.46.2.1 2002/07/01 17:41:55 he Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  *
     35  *	@(#)kern_ktrace.c	8.5 (Berkeley) 5/14/95
     36  */
     37 
     38 #include "opt_ktrace.h"
     39 
     40 #ifdef KTRACE
     41 
     42 #include <sys/param.h>
     43 #include <sys/systm.h>
     44 #include <sys/proc.h>
     45 #include <sys/file.h>
     46 #include <sys/namei.h>
     47 #include <sys/vnode.h>
     48 #include <sys/ktrace.h>
     49 #include <sys/malloc.h>
     50 #include <sys/syslog.h>
     51 #include <sys/filedesc.h>
     52 #include <sys/ioctl.h>
     53 
     54 #include <sys/mount.h>
     55 #include <sys/syscallargs.h>
     56 
     57 int	ktrace_common __P((struct proc *, int, int, int, struct file *));
     58 void	ktrinitheader __P((struct ktr_header *, struct proc *, int));
     59 int	ktrops __P((struct proc *, struct proc *, int, int, struct file *));
     60 int	ktrsetchildren __P((struct proc *, struct proc *, int, int,
     61     struct file *));
     62 int	ktrwrite __P((struct proc *, struct ktr_header *));
     63 int	ktrcanset __P((struct proc *, struct proc *));
     64 int	ktrsamefile __P((struct file *, struct file *));
     65 
     66 /*
     67  * "deep" compare of two files for the purposes of clearing a trace.
     68  * Returns true if they're the same open file, or if they point at the
     69  * same underlying vnode/socket.
     70  */
     71 
     72 int
     73 ktrsamefile (f1, f2)
     74 	struct file *f1, *f2;
     75 {
     76 	return ((f1 == f2) ||
     77 	    ((f1 != NULL) && (f2 != NULL) &&
     78 		(f1->f_type == f2->f_type) &&
     79 		(f1->f_data == f2->f_data)));
     80 }
     81 
     82 void
     83 ktrderef(p)
     84 	struct proc *p;
     85 {
     86 	struct file *fp = p->p_tracep;
     87 	p->p_traceflag = 0;
     88 	if (fp == NULL)
     89 		return;
     90 	FILE_USE(fp);
     91 	closef(fp, NULL);
     92 
     93 	p->p_tracep = NULL;
     94 }
     95 
     96 void
     97 ktradref(p)
     98 	struct proc *p;
     99 {
    100 	struct file *fp = p->p_tracep;
    101 
    102 	fp->f_count++;
    103 }
    104 
    105 void
    106 ktrinitheader(kth, p, type)
    107 	struct ktr_header *kth;
    108 	struct proc *p;
    109 	int type;
    110 {
    111 
    112 	memset(kth, 0, sizeof(*kth));
    113 	kth->ktr_type = type;
    114 	microtime(&kth->ktr_time);
    115 	kth->ktr_pid = p->p_pid;
    116 	memcpy(kth->ktr_comm, p->p_comm, MAXCOMLEN);
    117 }
    118 
    119 void
    120 ktrsyscall(p, code, argsize, args)
    121 	struct proc *p;
    122 	register_t code;
    123 	size_t argsize;
    124 	register_t args[];
    125 {
    126 	struct ktr_header kth;
    127 	struct ktr_syscall *ktp;
    128 	register_t *argp;
    129 	size_t len = sizeof(struct ktr_syscall) + argsize;
    130 	int i;
    131 
    132 	p->p_traceflag |= KTRFAC_ACTIVE;
    133 	ktrinitheader(&kth, p, KTR_SYSCALL);
    134 	ktp = malloc(len, M_TEMP, M_WAITOK);
    135 	ktp->ktr_code = code;
    136 	ktp->ktr_argsize = argsize;
    137 	argp = (register_t *)((char *)ktp + sizeof(struct ktr_syscall));
    138 	for (i = 0; i < (argsize / sizeof(*argp)); i++)
    139 		*argp++ = args[i];
    140 	kth.ktr_buf = (caddr_t)ktp;
    141 	kth.ktr_len = len;
    142 	(void) ktrwrite(p, &kth);
    143 	free(ktp, M_TEMP);
    144 	p->p_traceflag &= ~KTRFAC_ACTIVE;
    145 }
    146 
    147 void
    148 ktrsysret(p, code, error, retval)
    149 	struct proc *p;
    150 	register_t code;
    151 	int error;
    152 	register_t retval;
    153 {
    154 	struct ktr_header kth;
    155 	struct ktr_sysret ktp;
    156 
    157 	p->p_traceflag |= KTRFAC_ACTIVE;
    158 	ktrinitheader(&kth, p, KTR_SYSRET);
    159 	ktp.ktr_code = code;
    160 	ktp.ktr_eosys = 0;			/* XXX unused */
    161 	ktp.ktr_error = error;
    162 	ktp.ktr_retval = retval;		/* what about val2 ? */
    163 
    164 	kth.ktr_buf = (caddr_t)&ktp;
    165 	kth.ktr_len = sizeof(struct ktr_sysret);
    166 
    167 	(void) ktrwrite(p, &kth);
    168 	p->p_traceflag &= ~KTRFAC_ACTIVE;
    169 }
    170 
    171 void
    172 ktrnamei(p, path)
    173 	struct proc *p;
    174 	char *path;
    175 {
    176 	struct ktr_header kth;
    177 
    178 	p->p_traceflag |= KTRFAC_ACTIVE;
    179 	ktrinitheader(&kth, p, KTR_NAMEI);
    180 	kth.ktr_len = strlen(path);
    181 	kth.ktr_buf = path;
    182 
    183 	(void) ktrwrite(p, &kth);
    184 	p->p_traceflag &= ~KTRFAC_ACTIVE;
    185 }
    186 
    187 void
    188 ktremul(p)
    189 	struct proc *p;
    190 {
    191 	struct ktr_header kth;
    192 	char *emul = p->p_emul->e_name;
    193 
    194 	p->p_traceflag |= KTRFAC_ACTIVE;
    195 	ktrinitheader(&kth, p, KTR_EMUL);
    196 	kth.ktr_len = strlen(emul);
    197 	kth.ktr_buf = emul;
    198 
    199 	(void) ktrwrite(p, &kth);
    200 	p->p_traceflag &= ~KTRFAC_ACTIVE;
    201 }
    202 
    203 void
    204 ktrgenio(p, fd, rw, iov, len, error)
    205 	struct proc *p;
    206 	int fd;
    207 	enum uio_rw rw;
    208 	struct iovec *iov;
    209 	int len, error;
    210 {
    211 	struct ktr_header kth;
    212 	struct ktr_genio *ktp;
    213 	caddr_t cp;
    214 	int resid = len, cnt;
    215 	int buflen;
    216 
    217 	if (error)
    218 		return;
    219 
    220 	p->p_traceflag |= KTRFAC_ACTIVE;
    221 
    222 	buflen = min(PAGE_SIZE, len + sizeof(struct ktr_genio));
    223 
    224 	ktrinitheader(&kth, p, KTR_GENIO);
    225 	ktp = malloc(buflen, M_TEMP, M_WAITOK);
    226 	ktp->ktr_fd = fd;
    227 	ktp->ktr_rw = rw;
    228 
    229 	kth.ktr_buf = (caddr_t)ktp;
    230 
    231 	cp = (caddr_t)((char *)ktp + sizeof(struct ktr_genio));
    232 	buflen -= sizeof(struct ktr_genio);
    233 
    234 	while (resid > 0) {
    235 		KDASSERT(p->p_cpu != NULL);
    236 		KDASSERT(p->p_cpu == curcpu());
    237 		if (p->p_cpu->ci_schedstate.spc_flags & SPCF_SHOULDYIELD)
    238 			preempt(NULL);
    239 
    240 		cnt = min(iov->iov_len, buflen);
    241 		if (cnt > resid)
    242 			cnt = resid;
    243 		if (copyin(iov->iov_base, cp, cnt))
    244 			break;
    245 
    246 		kth.ktr_len = cnt + sizeof(struct ktr_genio);
    247 
    248 		if (__predict_false(ktrwrite(p, &kth) != 0))
    249 			break;
    250 
    251 		iov->iov_base = (caddr_t)iov->iov_base + cnt;
    252 		iov->iov_len -= cnt;
    253 
    254 		if (iov->iov_len == 0)
    255 			iov++;
    256 
    257 		resid -= cnt;
    258 	}
    259 
    260 	free(ktp, M_TEMP);
    261 	p->p_traceflag &= ~KTRFAC_ACTIVE;
    262 }
    263 
    264 void
    265 ktrpsig(p, sig, action, mask, code)
    266 	struct proc *p;
    267 	int sig;
    268 	sig_t action;
    269 	sigset_t *mask;
    270 	int code;
    271 {
    272 	struct ktr_header kth;
    273 	struct ktr_psig	kp;
    274 
    275 	p->p_traceflag |= KTRFAC_ACTIVE;
    276 	ktrinitheader(&kth, p, KTR_PSIG);
    277 	kp.signo = (char)sig;
    278 	kp.action = action;
    279 	kp.mask = *mask;
    280 	kp.code = code;
    281 	kth.ktr_buf = (caddr_t)&kp;
    282 	kth.ktr_len = sizeof(struct ktr_psig);
    283 
    284 	(void) ktrwrite(p, &kth);
    285 	p->p_traceflag &= ~KTRFAC_ACTIVE;
    286 }
    287 
    288 void
    289 ktrcsw(p, out, user)
    290 	struct proc *p;
    291 	int out, user;
    292 {
    293 	struct ktr_header kth;
    294 	struct ktr_csw kc;
    295 
    296 	p->p_traceflag |= KTRFAC_ACTIVE;
    297 	ktrinitheader(&kth, p, KTR_CSW);
    298 	kc.out = out;
    299 	kc.user = user;
    300 	kth.ktr_buf = (caddr_t)&kc;
    301 	kth.ktr_len = sizeof(struct ktr_csw);
    302 
    303 	(void) ktrwrite(p, &kth);
    304 	p->p_traceflag &= ~KTRFAC_ACTIVE;
    305 }
    306 
    307 /* Interface and common routines */
    308 
    309 int
    310 ktrace_common (curp, ops, facs, pid, fp)
    311 	struct proc *curp;
    312 	int ops, facs, pid;
    313 	struct file *fp;
    314 {
    315 	int ret = 0;
    316 	int error = 0;
    317 	int one = 1;
    318 	int descend;
    319 	struct proc *p;
    320 	struct pgrp *pg;
    321 
    322 	curp->p_traceflag |= KTRFAC_ACTIVE;
    323 	descend = ops & KTRFLAG_DESCEND;
    324 	facs = facs & ~((unsigned) KTRFAC_ROOT);
    325 
    326 	/*
    327 	 * Clear all uses of the tracefile
    328 	 */
    329 	if (KTROP(ops) == KTROP_CLEARFILE) {
    330 		proclist_lock_read();
    331 		for (p = LIST_FIRST(&allproc); p != NULL;
    332 		     p = LIST_NEXT(p, p_list)) {
    333 			if (ktrsamefile(p->p_tracep, fp)) {
    334 				if (ktrcanset(curp, p))
    335 					ktrderef(p);
    336 				else
    337 					error = EPERM;
    338 			}
    339 		}
    340 		proclist_unlock_read();
    341 		goto done;
    342 	}
    343 
    344 	/*
    345 	 * Mark fp non-blocking, to avoid problems from possible deadlocks.
    346 	 */
    347 
    348 	if (fp != NULL) {
    349 		fp->f_flag |= FNONBLOCK;
    350 		(*fp->f_ops->fo_ioctl)(fp, FIONBIO, (caddr_t)&one, curp);
    351 	}
    352 
    353 	/*
    354 	 * need something to (un)trace (XXX - why is this here?)
    355 	 */
    356 	if (!facs) {
    357 		error = EINVAL;
    358 		goto done;
    359 	}
    360 	/*
    361 	 * do it
    362 	 */
    363 	if (pid < 0) {
    364 		/*
    365 		 * by process group
    366 		 */
    367 		pg = pgfind(-pid);
    368 		if (pg == NULL) {
    369 			error = ESRCH;
    370 			goto done;
    371 		}
    372 		for (p = LIST_FIRST(&pg->pg_members); p != NULL;
    373 		     p = LIST_NEXT(p, p_pglist)) {
    374 			if (descend)
    375 				ret |= ktrsetchildren(curp, p, ops, facs, fp);
    376 			else
    377 				ret |= ktrops(curp, p, ops, facs, fp);
    378 		}
    379 
    380 	} else {
    381 		/*
    382 		 * by pid
    383 		 */
    384 		p = pfind(pid);
    385 		if (p == NULL) {
    386 			error = ESRCH;
    387 			goto done;
    388 		}
    389 		if (descend)
    390 			ret |= ktrsetchildren(curp, p, ops, facs, fp);
    391 		else
    392 			ret |= ktrops(curp, p, ops, facs, fp);
    393 	}
    394 	if (!ret)
    395 		error = EPERM;
    396 done:
    397 	curp->p_traceflag &= ~KTRFAC_ACTIVE;
    398 	return (error);
    399 }
    400 
    401 /*
    402  * ktrace system call
    403  */
    404 /* ARGSUSED */
    405 int
    406 sys_fktrace(curp, v, retval)
    407 	struct proc *curp;
    408 	void *v;
    409 	register_t *retval;
    410 {
    411 	struct sys_fktrace_args /* {
    412 		syscallarg(int) fd;
    413 		syscallarg(int) ops;
    414 		syscallarg(int) facs;
    415 		syscallarg(int) pid;
    416 	} */ *uap = v;
    417 	struct file *fp = NULL;
    418 	struct filedesc *fdp = curp->p_fd;
    419 
    420 	if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles ||
    421 	    (fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL ||
    422 	    (fp->f_flag & FWRITE) == 0)
    423 		return (EBADF);
    424 
    425 	return ktrace_common(curp, SCARG(uap, ops),
    426 	    SCARG(uap, facs), SCARG(uap, pid), fp);
    427 }
    428 
    429 /*
    430  * ktrace system call
    431  */
    432 /* ARGSUSED */
    433 int
    434 sys_ktrace(curp, v, retval)
    435 	struct proc *curp;
    436 	void *v;
    437 	register_t *retval;
    438 {
    439 	struct sys_ktrace_args /* {
    440 		syscallarg(const char *) fname;
    441 		syscallarg(int) ops;
    442 		syscallarg(int) facs;
    443 		syscallarg(int) pid;
    444 	} */ *uap = v;
    445 	struct vnode *vp = NULL;
    446 	struct file *fp = NULL;
    447 	int fd;
    448 	int ops = SCARG(uap, ops);
    449 	int error = 0;
    450 	struct nameidata nd;
    451 
    452 	ops = KTROP(ops) | (ops & KTRFLAG_DESCEND);
    453 
    454 	curp->p_traceflag |= KTRFAC_ACTIVE;
    455 	if (ops != KTROP_CLEAR) {
    456 		/*
    457 		 * an operation which requires a file argument.
    458 		 */
    459 		NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, fname),
    460 		    curp);
    461 		if ((error = vn_open(&nd, FREAD|FWRITE, 0)) != 0) {
    462 			curp->p_traceflag &= ~KTRFAC_ACTIVE;
    463 			return (error);
    464 		}
    465 		vp = nd.ni_vp;
    466 		VOP_UNLOCK(vp, 0);
    467 		if (vp->v_type != VREG) {
    468 			(void) vn_close(vp, FREAD|FWRITE, curp->p_ucred, curp);
    469 			curp->p_traceflag &= ~KTRFAC_ACTIVE;
    470 			return (EACCES);
    471 		}
    472 		/*
    473 		 * XXX This uses up a file descriptor slot in the
    474 		 * tracing process for the duration of this syscall.
    475 		 * This is not expected to be a problem.  If
    476 		 * falloc(NULL, ...) DTRT we could skip that part, but
    477 		 * that would require changing its interface to allow
    478 		 * the caller to pass in a ucred..
    479 		 *
    480 		 * This will FILE_USE the fp it returns, if any.
    481 		 * Keep it in use until we return.
    482 		 */
    483 		if ((error = falloc(curp, &fp, &fd)) != 0)
    484 			goto done;
    485 
    486 		fp->f_flag = FWRITE|FAPPEND;
    487 		fp->f_type = DTYPE_VNODE;
    488 		fp->f_ops = &vnops;
    489 		fp->f_data = (caddr_t)vp;
    490 		vp = NULL;
    491 	}
    492 	error = ktrace_common(curp, SCARG(uap, ops), SCARG(uap, facs),
    493 	    SCARG(uap, pid), fp);
    494 done:
    495 	if (vp != NULL)
    496 		(void) vn_close(vp, FWRITE, curp->p_ucred, curp);
    497 	if (fp != NULL) {
    498 		FILE_UNUSE(fp, curp);	/* release file */
    499 		fdrelease(curp, fd); 	/* release fd table slot */
    500 	}
    501 	return (error);
    502 }
    503 
    504 int
    505 ktrops(curp, p, ops, facs, fp)
    506 	struct proc *p, *curp;
    507 	int ops, facs;
    508 	struct file *fp;
    509 {
    510 
    511 	if (!ktrcanset(curp, p))
    512 		return (0);
    513 	if (KTROP(ops) == KTROP_SET) {
    514 		if (p->p_tracep != fp) {
    515 			/*
    516 			 * if trace file already in use, relinquish
    517 			 */
    518 			ktrderef(p);
    519 			p->p_tracep = fp;
    520 			ktradref(p);
    521 		}
    522 		p->p_traceflag |= facs;
    523 		if (curp->p_ucred->cr_uid == 0)
    524 			p->p_traceflag |= KTRFAC_ROOT;
    525 	} else {
    526 		/* KTROP_CLEAR */
    527 		if (((p->p_traceflag &= ~facs) & KTRFAC_MASK) == 0) {
    528 			/* no more tracing */
    529 			ktrderef(p);
    530 		}
    531 	}
    532 
    533 	/*
    534 	 * Emit an emulation record, every time there is a ktrace
    535 	 * change/attach request.
    536 	 */
    537 	if (KTRPOINT(p, KTR_EMUL))
    538 		ktremul(p);
    539 
    540 	return (1);
    541 }
    542 
    543 int
    544 ktrsetchildren(curp, top, ops, facs, fp)
    545 	struct proc *curp, *top;
    546 	int ops, facs;
    547 	struct file *fp;
    548 {
    549 	struct proc *p;
    550 	int ret = 0;
    551 
    552 	p = top;
    553 	for (;;) {
    554 		ret |= ktrops(curp, p, ops, facs, fp);
    555 		/*
    556 		 * If this process has children, descend to them next,
    557 		 * otherwise do any siblings, and if done with this level,
    558 		 * follow back up the tree (but not past top).
    559 		 */
    560 		if (LIST_FIRST(&p->p_children) != NULL)
    561 			p = LIST_FIRST(&p->p_children);
    562 		else for (;;) {
    563 			if (p == top)
    564 				return (ret);
    565 			if (LIST_NEXT(p, p_sibling) != NULL) {
    566 				p = LIST_NEXT(p, p_sibling);
    567 				break;
    568 			}
    569 			p = p->p_pptr;
    570 		}
    571 	}
    572 	/*NOTREACHED*/
    573 }
    574 
    575 int
    576 ktrwrite(p, kth)
    577 	struct proc *p;
    578 	struct ktr_header *kth;
    579 {
    580 	struct uio auio;
    581 	struct iovec aiov[2];
    582 	int error, tries;
    583 	struct file *fp = p->p_tracep;
    584 
    585 	if (fp == NULL)
    586 		return 0;
    587 
    588 	auio.uio_iov = &aiov[0];
    589 	auio.uio_offset = 0;
    590 	auio.uio_segflg = UIO_SYSSPACE;
    591 	auio.uio_rw = UIO_WRITE;
    592 	aiov[0].iov_base = (caddr_t)kth;
    593 	aiov[0].iov_len = sizeof(struct ktr_header);
    594 	auio.uio_resid = sizeof(struct ktr_header);
    595 	auio.uio_iovcnt = 1;
    596 	auio.uio_procp = (struct proc *)0;
    597 	if (kth->ktr_len > 0) {
    598 		auio.uio_iovcnt++;
    599 		aiov[1].iov_base = kth->ktr_buf;
    600 		aiov[1].iov_len = kth->ktr_len;
    601 		auio.uio_resid += kth->ktr_len;
    602 	}
    603 
    604 	FILE_USE(fp);
    605 
    606 	tries = 0;
    607 	do {
    608 		error = (*fp->f_ops->fo_write)(fp, &fp->f_offset, &auio,
    609 		    fp->f_cred, FOF_UPDATE_OFFSET);
    610 		tries++;
    611 		if (error == EWOULDBLOCK)
    612 		  	yield();
    613 	} while ((error == EWOULDBLOCK) && (tries < 3));
    614 	FILE_UNUSE(fp, NULL);
    615 
    616 	if (__predict_true(error == 0))
    617 		return (0);
    618 	/*
    619 	 * If error encountered, give up tracing on this vnode.  Don't report
    620 	 * EPIPE as this can easily happen with fktrace()/ktruss.
    621 	 */
    622 	if (error != EPIPE)
    623 		log(LOG_NOTICE,
    624 		    "ktrace write failed, errno %d, tracing stopped\n",
    625 		    error);
    626 	proclist_lock_read();
    627 	for (p = LIST_FIRST(&allproc); p != NULL; p = LIST_NEXT(p, p_list)) {
    628 		if (ktrsamefile(p->p_tracep, fp))
    629 			ktrderef(p);
    630 	}
    631 	proclist_unlock_read();
    632 
    633 	return (error);
    634 }
    635 
    636 /*
    637  * Return true if caller has permission to set the ktracing state
    638  * of target.  Essentially, the target can't possess any
    639  * more permissions than the caller.  KTRFAC_ROOT signifies that
    640  * root previously set the tracing status on the target process, and
    641  * so, only root may further change it.
    642  *
    643  * TODO: check groups.  use caller effective gid.
    644  */
    645 int
    646 ktrcanset(callp, targetp)
    647 	struct proc *callp, *targetp;
    648 {
    649 	struct pcred *caller = callp->p_cred;
    650 	struct pcred *target = targetp->p_cred;
    651 
    652 	if ((caller->pc_ucred->cr_uid == target->p_ruid &&
    653 	     target->p_ruid == target->p_svuid &&
    654 	     caller->p_rgid == target->p_rgid &&	/* XXX */
    655 	     target->p_rgid == target->p_svgid &&
    656 	     (targetp->p_traceflag & KTRFAC_ROOT) == 0 &&
    657 	     (targetp->p_flag & P_SUGID) == 0) ||
    658 	     caller->pc_ucred->cr_uid == 0)
    659 		return (1);
    660 
    661 	return (0);
    662 }
    663 
    664 #endif
    665