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 1.7 2003/07/24 01:41:25 dillon Exp $
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/sysproto.h>
39 #include <sys/vnode.h>
40 #include <sys/ptrace.h>
42 #include <machine/reg.h>
46 #include <vm/vm_map.h>
47 #include <vm/vm_page.h>
50 #include <miscfs/procfs/procfs.h>
51 #include <sys/thread2.h>
53 /* use the equivalent procfs code */
56 pread (struct proc *procp, unsigned int addr, unsigned int *retval) {
61 int page_offset; /* offset into page */
62 vm_offset_t pageno; /* page number */
63 vm_map_entry_t out_entry;
68 /* Map page into kernel space */
70 map = &procp->p_vmspace->vm_map;
72 page_offset = addr - trunc_page(addr);
73 pageno = trunc_page(addr);
76 rv = vm_map_lookup (&tmap, pageno, VM_PROT_READ, &out_entry,
77 &object, &pindex, &out_prot, &wired);
79 if (rv != KERN_SUCCESS)
82 vm_map_lookup_done (tmap, out_entry);
84 /* Find space in kernel_map for the page we're interested in */
85 rv = vm_map_find (kernel_map, object, IDX_TO_OFF(pindex),
86 &kva, PAGE_SIZE, 0, VM_PROT_ALL, VM_PROT_ALL, 0);
89 vm_object_reference (object);
91 rv = vm_map_pageable (kernel_map, kva, kva + PAGE_SIZE, 0);
94 bcopy ((caddr_t)kva + page_offset,
95 retval, sizeof *retval);
97 vm_map_remove (kernel_map, kva, kva + PAGE_SIZE);
104 pwrite (struct proc *procp, unsigned int addr, unsigned int datum) {
109 int page_offset; /* offset into page */
110 vm_offset_t pageno; /* page number */
111 vm_map_entry_t out_entry;
115 boolean_t fix_prot = 0;
117 /* Map page into kernel space */
119 map = &procp->p_vmspace->vm_map;
121 page_offset = addr - trunc_page(addr);
122 pageno = trunc_page(addr);
125 * Check the permissions for the area we're interested in.
128 if (vm_map_check_protection (map, pageno, pageno + PAGE_SIZE,
129 VM_PROT_WRITE) == FALSE) {
131 * If the page was not writable, we make it so.
132 * XXX It is possible a page may *not* be read/executable,
133 * if a process changes that!
136 /* The page isn't writable, so let's try making it so... */
137 if ((rv = vm_map_protect (map, pageno, pageno + PAGE_SIZE,
138 VM_PROT_ALL, 0)) != KERN_SUCCESS)
139 return EFAULT; /* I guess... */
143 * Now we need to get the page. out_entry, out_prot, wired, and
144 * single_use aren't used. One would think the vm code would be
145 * a *bit* nicer... We use tmap because vm_map_lookup() can
146 * change the map argument.
150 rv = vm_map_lookup (&tmap, pageno, VM_PROT_WRITE, &out_entry,
151 &object, &pindex, &out_prot, &wired);
152 if (rv != KERN_SUCCESS) {
157 * Okay, we've got the page. Let's release tmap.
160 vm_map_lookup_done (tmap, out_entry);
163 * Fault the page in...
166 rv = vm_fault(map, pageno, VM_PROT_WRITE|VM_PROT_READ, FALSE);
167 if (rv != KERN_SUCCESS)
170 /* Find space in kernel_map for the page we're interested in */
171 rv = vm_map_find (kernel_map, object, IDX_TO_OFF(pindex),
173 VM_PROT_ALL, VM_PROT_ALL, 0);
175 vm_object_reference (object);
177 rv = vm_map_pageable (kernel_map, kva, kva + PAGE_SIZE, 0);
179 bcopy (&datum, (caddr_t)kva + page_offset, sizeof datum);
181 vm_map_remove (kernel_map, kva, kva + PAGE_SIZE);
185 vm_map_protect (map, pageno, pageno + PAGE_SIZE,
186 VM_PROT_READ|VM_PROT_EXECUTE, 0);
192 * Process debugging system call.
195 ptrace(struct ptrace_args *uap)
197 struct proc *p = curproc;
200 * XXX this obfuscation is to reduce stack usage, but the register
201 * structs may be too large to put on the stack anyway.
204 struct ptrace_io_desc piod;
221 error = copyin(uap->addr, &r.reg, sizeof r.reg);
224 error = copyin(uap->addr, &r.fpreg, sizeof r.fpreg);
228 error = copyin(uap->addr, &r.dbreg, sizeof r.dbreg);
232 error = copyin(uap->addr, &r.piod, sizeof r.piod);
240 error = kern_ptrace(p, uap->req, uap->pid, addr, uap->data);
246 (void)copyout(&r.piod, uap->addr, sizeof r.piod);
249 error = copyout(&r.reg, uap->addr, sizeof r.reg);
252 error = copyout(&r.fpreg, uap->addr, sizeof r.fpreg);
256 error = copyout(&r.dbreg, uap->addr, sizeof r.dbreg);
265 kern_ptrace(struct proc *curp, int req, pid_t pid, void *addr, int data)
270 struct ptrace_io_desc *piod;
275 if (req == PT_TRACE_ME)
278 if ((p = pfind(pid)) == NULL)
281 if (!PRISON_CHECK(curp->p_ucred, p->p_ucred))
284 /* Can't trace a process that's currently exec'ing. */
285 if ((p->p_flag & P_INEXEC) != 0)
298 if (p->p_pid == curp->p_pid)
302 if (p->p_flag & P_TRACED)
305 if (curp->p_flag & P_TRACED)
306 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr)
310 /* not owned by you, has done setuid (unless you're root) */
311 if ((p->p_ucred->cr_ruid != curp->p_ucred->cr_ruid) ||
312 (p->p_flag & P_SUGID)) {
313 if ((error = suser(curp->p_thread)) != 0)
317 /* can't trace init when securelevel > 0 */
318 if (securelevel > 0 && p->p_pid == 1)
351 /* not being traced... */
352 if ((p->p_flag & P_TRACED) == 0)
355 /* not being traced by YOU */
356 if (p->p_pptr != curp)
359 /* not currently stopped */
360 if (p->p_stat != SSTOP || (p->p_flag & P_WAITED) == 0)
372 * Single step fixup ala procfs
378 * Actually do the requests
381 curp->p_retval[0] = 0;
385 /* set my trace flag and "owner" so it can read/write me */
386 p->p_flag |= P_TRACED;
387 p->p_oppid = p->p_pptr->p_pid;
391 /* security check done above */
392 p->p_flag |= P_TRACED;
393 p->p_oppid = p->p_pptr->p_pid;
394 if (p->p_pptr != curp)
395 proc_reparent(p, curp);
397 goto sendsig; /* in PT_CONTINUE below */
402 if ((req != PT_STEP) && ((unsigned)data > _SIG_MAXSIG))
407 if (req == PT_STEP) {
408 if ((error = ptrace_single_step (p))) {
414 if (addr != (void *)1) {
415 if ((error = ptrace_set_pc (p,
416 (u_long)(uintfptr_t)addr))) {
423 if (req == PT_DETACH) {
424 /* reset process parent */
425 if (p->p_oppid != p->p_pptr->p_pid) {
428 pp = pfind(p->p_oppid);
429 proc_reparent(p, pp ? pp : initproc);
432 p->p_flag &= ~(P_TRACED | P_WAITED);
435 /* should we send SIGCHLD? */
439 /* deliver or queue signal */
441 if (p->p_stat == SSTOP) {
457 /* write = 0 set above */
458 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp;
459 iov.iov_len = sizeof(int);
462 uio.uio_offset = (off_t)(uintptr_t)addr;
463 uio.uio_resid = sizeof(int);
464 uio.uio_segflg = UIO_SYSSPACE;
465 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
466 uio.uio_td = p->p_thread;
467 error = procfs_domem(curp, p, NULL, &uio);
468 if (uio.uio_resid != 0) {
470 * XXX procfs_domem() doesn't currently return ENOSPC,
471 * so I think write() can bogusly return 0.
472 * XXX what happens for short writes? We don't want
473 * to write partial data.
474 * XXX procfs_domem() returns EPERM for other invalid
475 * addresses. Convert this to EINVAL. Does this
476 * clobber returns of EPERM for other reasons?
478 if (error == 0 || error == ENOSPC || error == EPERM)
479 error = EINVAL; /* EOF */
482 curp->p_retval[0] = tmp;
487 iov.iov_base = piod->piod_addr;
488 iov.iov_len = piod->piod_len;
491 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
492 uio.uio_resid = piod->piod_len;
493 uio.uio_segflg = UIO_USERSPACE;
494 uio.uio_td = p->p_thread;
495 switch (piod->piod_op) {
498 uio.uio_rw = UIO_READ;
502 uio.uio_rw = UIO_WRITE;
507 error = procfs_domem(curp, p, NULL, &uio);
508 piod->piod_len -= uio.uio_resid;
513 goto sendsig; /* in PT_CONTINUE above */
519 #endif /* PT_SETREGS */
522 /* write = 0 above */
523 #endif /* PT_SETREGS */
524 #if defined(PT_SETREGS) || defined(PT_GETREGS)
525 if (!procfs_validregs(p)) /* no P_SYSTEM procs please */
529 iov.iov_len = sizeof(struct reg);
533 uio.uio_resid = sizeof(struct reg);
534 uio.uio_segflg = UIO_SYSSPACE;
535 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
536 uio.uio_td = curp->p_thread;
537 return (procfs_doregs(curp, p, NULL, &uio));
539 #endif /* defined(PT_SETREGS) || defined(PT_GETREGS) */
545 #endif /* PT_SETFPREGS */
548 /* write = 0 above */
549 #endif /* PT_SETFPREGS */
550 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS)
551 if (!procfs_validfpregs(p)) /* no P_SYSTEM procs please */
555 iov.iov_len = sizeof(struct fpreg);
559 uio.uio_resid = sizeof(struct fpreg);
560 uio.uio_segflg = UIO_SYSSPACE;
561 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
562 uio.uio_td = curp->p_thread;
563 return (procfs_dofpregs(curp, p, NULL, &uio));
565 #endif /* defined(PT_SETFPREGS) || defined(PT_GETFPREGS) */
571 #endif /* PT_SETDBREGS */
574 /* write = 0 above */
575 #endif /* PT_SETDBREGS */
576 #if defined(PT_SETDBREGS) || defined(PT_GETDBREGS)
577 if (!procfs_validdbregs(p)) /* no P_SYSTEM procs please */
581 iov.iov_len = sizeof(struct dbreg);
585 uio.uio_resid = sizeof(struct dbreg);
586 uio.uio_segflg = UIO_SYSSPACE;
587 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
588 uio.uio_td = curp->p_thread;
589 return (procfs_dodbregs(curp, p, NULL, &uio));
591 #endif /* defined(PT_SETDBREGS) || defined(PT_GETDBREGS) */
609 * Stop a process because of a procfs event;
610 * stay stopped until p->p_step is cleared
611 * (cleared by PIOCCONT in procfs).
615 stopevent(struct proc *p, unsigned int event, unsigned int val)
621 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */
623 p->p_stype = event; /* Which event caused the stop? */
624 tsleep(&p->p_step, 0, "stopevent", 0);