2 * Copyright (c) 1994, Sean Eric Fagan
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Sean Eric Fagan.
16 * 4. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * $FreeBSD: src/sys/kern/sys_process.c,v 1.51.2.6 2003/01/08 03:06:45 kan Exp $
32 * $DragonFly: src/sys/kern/sys_process.c,v 1.30 2007/02/19 01:14:23 corecode Exp $
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/sysproto.h>
40 #include <sys/vnode.h>
41 #include <sys/ptrace.h>
47 #include <vm/vm_map.h>
48 #include <vm/vm_page.h>
51 #include <vfs/procfs/procfs.h>
53 #include <sys/thread2.h>
54 #include <sys/spinlock2.h>
56 /* use the equivalent procfs code */
59 pread (struct proc *procp, unsigned int addr, unsigned int *retval) {
64 int page_offset; /* offset into page */
65 vm_offset_t pageno; /* page number */
66 vm_map_entry_t out_entry;
71 /* Map page into kernel space */
73 map = &procp->p_vmspace->vm_map;
75 page_offset = addr - trunc_page(addr);
76 pageno = trunc_page(addr);
79 rv = vm_map_lookup(&tmap, pageno, VM_PROT_READ, &out_entry,
80 &object, &pindex, &out_prot, &wired);
82 if (rv != KERN_SUCCESS)
85 vm_map_lookup_done (tmap, out_entry, 0);
87 /* Find space in kernel_map for the page we're interested in */
88 rv = vm_map_find (&kernel_map, object, NULL,
89 IDX_TO_OFF(pindex), &kva, PAGE_SIZE,
91 VM_MAPTYPE_NORMAL, VM_SUBSYS_PROC,
92 VM_PROT_ALL, VM_PROT_ALL, 0);
95 vm_object_reference XXX (object);
97 rv = vm_map_wire (&kernel_map, kva, kva + PAGE_SIZE, 0);
100 bcopy ((caddr_t)kva + page_offset,
101 retval, sizeof *retval);
103 vm_map_remove (&kernel_map, kva, kva + PAGE_SIZE);
110 pwrite (struct proc *procp, unsigned int addr, unsigned int datum) {
115 int page_offset; /* offset into page */
116 vm_offset_t pageno; /* page number */
117 vm_map_entry_t out_entry;
121 boolean_t fix_prot = 0;
123 /* Map page into kernel space */
125 map = &procp->p_vmspace->vm_map;
127 page_offset = addr - trunc_page(addr);
128 pageno = trunc_page(addr);
131 * Check the permissions for the area we're interested in.
134 if (vm_map_check_protection (map, pageno, pageno + PAGE_SIZE,
135 VM_PROT_WRITE, FALSE) == FALSE) {
137 * If the page was not writable, we make it so.
138 * XXX It is possible a page may *not* be read/executable,
139 * if a process changes that!
142 /* The page isn't writable, so let's try making it so... */
143 if ((rv = vm_map_protect (map, pageno, pageno + PAGE_SIZE,
144 VM_PROT_ALL, 0)) != KERN_SUCCESS)
145 return EFAULT; /* I guess... */
149 * Now we need to get the page. out_entry, out_prot, wired, and
150 * single_use aren't used. One would think the vm code would be
151 * a *bit* nicer... We use tmap because vm_map_lookup() can
152 * change the map argument.
156 rv = vm_map_lookup(&tmap, pageno, VM_PROT_WRITE, &out_entry,
157 &object, &pindex, &out_prot, &wired);
158 if (rv != KERN_SUCCESS)
162 * Okay, we've got the page. Let's release tmap.
164 vm_map_lookup_done (tmap, out_entry, 0);
167 * Fault the page in...
169 rv = vm_fault(map, pageno, VM_PROT_WRITE|VM_PROT_READ, FALSE);
170 if (rv != KERN_SUCCESS)
173 /* Find space in kernel_map for the page we're interested in */
174 rv = vm_map_find (&kernel_map, object, NULL,
175 IDX_TO_OFF(pindex), &kva, PAGE_SIZE,
177 VM_MAPTYPE_NORMAL, VM_SUBSYS_PROC,
178 VM_PROT_ALL, VM_PROT_ALL, 0);
180 vm_object_reference XXX (object);
182 rv = vm_map_wire (&kernel_map, kva, kva + PAGE_SIZE, 0);
184 bcopy (&datum, (caddr_t)kva + page_offset, sizeof datum);
186 vm_map_remove (&kernel_map, kva, kva + PAGE_SIZE);
190 vm_map_protect (map, pageno, pageno + PAGE_SIZE,
191 VM_PROT_READ|VM_PROT_EXECUTE, 0);
197 * Process debugging system call.
202 sys_ptrace(struct ptrace_args *uap)
204 struct proc *p = curproc;
207 * XXX this obfuscation is to reduce stack usage, but the register
208 * structs may be too large to put on the stack anyway.
211 struct ptrace_io_desc piod;
228 error = copyin(uap->addr, &r.reg, sizeof r.reg);
231 error = copyin(uap->addr, &r.fpreg, sizeof r.fpreg);
235 error = copyin(uap->addr, &r.dbreg, sizeof r.dbreg);
239 error = copyin(uap->addr, &r.piod, sizeof r.piod);
247 error = kern_ptrace(p, uap->req, uap->pid, addr, uap->data,
248 &uap->sysmsg_result);
254 (void)copyout(&r.piod, uap->addr, sizeof r.piod);
257 error = copyout(&r.reg, uap->addr, sizeof r.reg);
260 error = copyout(&r.fpreg, uap->addr, sizeof r.fpreg);
264 error = copyout(&r.dbreg, uap->addr, sizeof r.dbreg);
273 kern_ptrace(struct proc *curp, int req, pid_t pid, void *addr,
280 struct ptrace_io_desc *piod;
286 if (req == PT_TRACE_ME) {
290 if ((p = pfind(pid)) == NULL)
293 if (!PRISON_CHECK(curp->p_ucred, p->p_ucred)) {
297 if (p->p_flags & P_SYSTEM) {
302 lwkt_gettoken(&p->p_token);
303 /* Can't trace a process that's currently exec'ing. */
304 if ((p->p_flags & P_INEXEC) != 0) {
305 lwkt_reltoken(&p->p_token);
320 if (p->p_pid == curp->p_pid) {
321 lwkt_reltoken(&p->p_token);
327 if (p->p_flags & P_TRACED) {
328 lwkt_reltoken(&p->p_token);
333 if (curp->p_flags & P_TRACED)
334 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr)
336 lwkt_reltoken(&p->p_token);
341 /* not owned by you, has done setuid (unless you're root) */
342 if ((p->p_ucred->cr_ruid != curp->p_ucred->cr_ruid) ||
343 (p->p_flags & P_SUGID)) {
344 if ((error = priv_check_cred(curp->p_ucred, PRIV_ROOT, 0)) != 0) {
345 lwkt_reltoken(&p->p_token);
351 /* can't trace init when securelevel > 0 */
352 if (securelevel > 0 && p->p_pid == 1) {
353 lwkt_reltoken(&p->p_token);
388 /* not being traced... */
389 if ((p->p_flags & P_TRACED) == 0) {
390 lwkt_reltoken(&p->p_token);
395 /* not being traced by YOU */
396 if (p->p_pptr != curp) {
397 lwkt_reltoken(&p->p_token);
402 /* not currently stopped */
403 if (p->p_stat != SSTOP ||
404 (p->p_flags & P_WAITED) == 0) {
405 lwkt_reltoken(&p->p_token);
414 lwkt_reltoken(&p->p_token);
420 lp = FIRST_LWP_IN_PROC(p);
423 * Single step fixup ala procfs
429 * Actually do the requests
436 /* set my trace flag and "owner" so it can read/write me */
437 p->p_flags |= P_TRACED;
438 p->p_oppid = p->p_pptr->p_pid;
439 lwkt_reltoken(&p->p_token);
444 /* security check done above */
445 p->p_flags |= P_TRACED;
446 p->p_oppid = p->p_pptr->p_pid;
447 proc_reparent(p, curp);
449 goto sendsig; /* in PT_CONTINUE below */
454 /* Zero means do not send any signal */
455 if (data < 0 || data > _SIG_MAXSIG) {
456 lwkt_reltoken(&p->p_token);
463 if (req == PT_STEP) {
464 if ((error = ptrace_single_step (lp))) {
466 lwkt_reltoken(&p->p_token);
472 if (addr != (void *)1) {
473 if ((error = ptrace_set_pc (lp,
474 (u_long)(uintfptr_t)addr))) {
476 lwkt_reltoken(&p->p_token);
483 if (req == PT_DETACH) {
484 /* reset process parent */
485 if (p->p_oppid != p->p_pptr->p_pid) {
488 pp = pfind(p->p_oppid);
490 proc_reparent(p, pp);
495 p->p_flags &= ~(P_TRACED | P_WAITED);
498 /* should we send SIGCHLD? */
503 * Deliver or queue signal. If the process is stopped
504 * force it to be SACTIVE again.
507 if (p->p_stat == SSTOP) {
509 proc_unstop(p, SSTOP);
514 lwkt_reltoken(&p->p_token);
525 * NOTE! uio_offset represents the offset in the target
526 * process. The iov is in the current process (the guy
527 * making the ptrace call) so uio_td must be the current
528 * process (though for a SYSSPACE transfer it doesn't
532 /* write = 0 set above */
533 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp;
534 iov.iov_len = sizeof(int);
537 uio.uio_offset = (off_t)(uintptr_t)addr;
538 uio.uio_resid = sizeof(int);
539 uio.uio_segflg = UIO_SYSSPACE;
540 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
541 uio.uio_td = curthread;
542 error = procfs_domem(curp, lp, NULL, &uio);
543 if (uio.uio_resid != 0) {
545 * XXX procfs_domem() doesn't currently return ENOSPC,
546 * so I think write() can bogusly return 0.
547 * XXX what happens for short writes? We don't want
548 * to write partial data.
549 * XXX procfs_domem() returns EPERM for other invalid
550 * addresses. Convert this to EINVAL. Does this
551 * clobber returns of EPERM for other reasons?
553 if (error == 0 || error == ENOSPC || error == EPERM)
554 error = EINVAL; /* EOF */
558 lwkt_reltoken(&p->p_token);
564 * NOTE! uio_offset represents the offset in the target
565 * process. The iov is in the current process (the guy
566 * making the ptrace call) so uio_td must be the current
570 iov.iov_base = piod->piod_addr;
571 iov.iov_len = piod->piod_len;
574 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
575 uio.uio_resid = piod->piod_len;
576 uio.uio_segflg = UIO_USERSPACE;
577 uio.uio_td = curthread;
578 switch (piod->piod_op) {
581 uio.uio_rw = UIO_READ;
585 uio.uio_rw = UIO_WRITE;
588 lwkt_reltoken(&p->p_token);
592 error = procfs_domem(curp, lp, NULL, &uio);
593 piod->piod_len -= uio.uio_resid;
594 lwkt_reltoken(&p->p_token);
600 goto sendsig; /* in PT_CONTINUE above */
606 #endif /* PT_SETREGS */
609 /* write = 0 above */
610 #endif /* PT_SETREGS */
611 #if defined(PT_SETREGS) || defined(PT_GETREGS)
612 if (!procfs_validregs(lp)) {
613 lwkt_reltoken(&p->p_token);
618 iov.iov_len = sizeof(struct reg);
622 uio.uio_resid = sizeof(struct reg);
623 uio.uio_segflg = UIO_SYSSPACE;
624 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
625 uio.uio_td = curthread;
626 t = procfs_doregs(curp, lp, NULL, &uio);
627 lwkt_reltoken(&p->p_token);
631 #endif /* defined(PT_SETREGS) || defined(PT_GETREGS) */
637 #endif /* PT_SETFPREGS */
640 /* write = 0 above */
641 #endif /* PT_SETFPREGS */
642 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS)
643 if (!procfs_validfpregs(lp)) {
644 lwkt_reltoken(&p->p_token);
649 iov.iov_len = sizeof(struct fpreg);
653 uio.uio_resid = sizeof(struct fpreg);
654 uio.uio_segflg = UIO_SYSSPACE;
655 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
656 uio.uio_td = curthread;
657 t = procfs_dofpregs(curp, lp, NULL, &uio);
658 lwkt_reltoken(&p->p_token);
662 #endif /* defined(PT_SETFPREGS) || defined(PT_GETFPREGS) */
668 #endif /* PT_SETDBREGS */
671 /* write = 0 above */
672 #endif /* PT_SETDBREGS */
673 #if defined(PT_SETDBREGS) || defined(PT_GETDBREGS)
674 if (!procfs_validdbregs(lp)) {
675 lwkt_reltoken(&p->p_token);
680 iov.iov_len = sizeof(struct dbreg);
684 uio.uio_resid = sizeof(struct dbreg);
685 uio.uio_segflg = UIO_SYSSPACE;
686 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
687 uio.uio_td = curthread;
688 t = procfs_dodbregs(curp, lp, NULL, &uio);
689 lwkt_reltoken(&p->p_token);
693 #endif /* defined(PT_SETDBREGS) || defined(PT_GETDBREGS) */
699 lwkt_reltoken(&p->p_token);
706 trace_req(struct proc *p)
714 * Stop a process because of a procfs event. Stay stopped until p->p_step
715 * is cleared (cleared by PIOCCONT in procfs).
720 stopevent(struct proc *p, unsigned int event, unsigned int val)
723 * Set event info. Recheck p_stops in case we are
724 * racing a close() on procfs.
726 spin_lock(&p->p_spin);
727 if ((p->p_stops & event) == 0) {
728 spin_unlock(&p->p_spin);
734 tsleep_interlock(&p->p_step, 0);
735 spin_unlock(&p->p_spin);
738 * Wakeup any PIOCWAITing procs and wait for p_step to
743 tsleep(&p->p_step, PINTERLOCKED, "stopevent", 0);
744 spin_lock(&p->p_spin);
745 if (p->p_step == 0) {
746 spin_unlock(&p->p_spin);
749 tsleep_interlock(&p->p_step, 0);
750 spin_unlock(&p->p_spin);