sys/kern/sys_process.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-4-Clause
   3  *
   4  * Copyright (c) 1994, Sean Eric Fagan
   5  * 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 Sean Eric Fagan.
  18  * 4. The name of the author may not be used to endorse or promote products
  19  *    derived from this software without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/ktr.h>
  40 #include <sys/limits.h>
  41 #include <sys/lock.h>
  42 #include <sys/mutex.h>
  43 #include <sys/syscallsubr.h>
  44 #include <sys/sysent.h>
  45 #include <sys/sysproto.h>
  46 #include <sys/priv.h>
  47 #include <sys/proc.h>
  48 #include <sys/vnode.h>
  49 #include <sys/ptrace.h>
  50 #include <sys/rwlock.h>
  51 #include <sys/sx.h>
  52 #include <sys/malloc.h>
  53 #include <sys/signalvar.h>
  54
  55 #include <machine/reg.h>
  56
  57 #include <security/audit/audit.h>
  58
  59 #include <vm/vm.h>
  60 #include <vm/pmap.h>
  61 #include <vm/vm_extern.h>
  62 #include <vm/vm_map.h>
  63 #include <vm/vm_kern.h>
  64 #include <vm/vm_object.h>
  65 #include <vm/vm_page.h>
  66 #include <vm/vm_param.h>
  67
  68 #ifdef COMPAT_FREEBSD32
  69 #include <sys/procfs.h>
  70 #include <compat/freebsd32/freebsd32_signal.h>
  71
  72 struct ptrace_io_desc32 {
  73         int             piod_op;
  74         uint32_t        piod_offs;
  75         uint32_t        piod_addr;
  76         uint32_t        piod_len;
  77 };
  78
  79 struct ptrace_sc_ret32 {
  80         uint32_t        sr_retval[2];
  81         int             sr_error;
  82 };
  83
  84 struct ptrace_vm_entry32 {
  85         int             pve_entry;
  86         int             pve_timestamp;
  87         uint32_t        pve_start;
  88         uint32_t        pve_end;
  89         uint32_t        pve_offset;
  90         u_int           pve_prot;
  91         u_int           pve_pathlen;
  92         int32_t         pve_fileid;
  93         u_int           pve_fsid;
  94         uint32_t        pve_path;
  95 };
  96 #endif
  97
  98 /*
  99  * Functions implemented using PROC_ACTION():
 100  *
 101  * proc_read_regs(proc, regs)
 102  *      Get the current user-visible register set from the process
 103  *      and copy it into the regs structure (<machine/reg.h>).
 104  *      The process is stopped at the time read_regs is called.
 105  *
 106  * proc_write_regs(proc, regs)
 107  *      Update the current register set from the passed in regs
 108  *      structure.  Take care to avoid clobbering special CPU
 109  *      registers or privileged bits in the PSL.
 110  *      Depending on the architecture this may have fix-up work to do,
 111  *      especially if the IAR or PCW are modified.
 112  *      The process is stopped at the time write_regs is called.
 113  *
 114  * proc_read_fpregs, proc_write_fpregs
 115  *      deal with the floating point register set, otherwise as above.
 116  *
 117  * proc_read_dbregs, proc_write_dbregs
 118  *      deal with the processor debug register set, otherwise as above.
 119  *
 120  * proc_sstep(proc)
 121  *      Arrange for the process to trap after executing a single instruction.
 122  */
 123
 124 #define PROC_ACTION(action) do {                                        \
 125         int error;                                                      \
 126                                                                         \
 127         PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);                        \
 128         if ((td->td_proc->p_flag & P_INMEM) == 0)                       \
 129                 error = EIO;                                            \
 130         else                                                            \
 131                 error = (action);                                       \
 132         return (error);                                                 \
 133 } while(0)
 134
 135 int
 136 proc_read_regs(struct thread *td, struct reg *regs)
 137 {
 138
 139         PROC_ACTION(fill_regs(td, regs));
 140 }
 141
 142 int
 143 proc_write_regs(struct thread *td, struct reg *regs)
 144 {
 145
 146         PROC_ACTION(set_regs(td, regs));
 147 }
 148
 149 int
 150 proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
 151 {
 152
 153         PROC_ACTION(fill_dbregs(td, dbregs));
 154 }
 155
 156 int
 157 proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
 158 {
 159
 160         PROC_ACTION(set_dbregs(td, dbregs));
 161 }
 162
 163 /*
 164  * Ptrace doesn't support fpregs at all, and there are no security holes
 165  * or translations for fpregs, so we can just copy them.
 166  */
 167 int
 168 proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
 169 {
 170
 171         PROC_ACTION(fill_fpregs(td, fpregs));
 172 }
 173
 174 int
 175 proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
 176 {
 177
 178         PROC_ACTION(set_fpregs(td, fpregs));
 179 }
 180
 181 #ifdef COMPAT_FREEBSD32
 182 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
 183 int
 184 proc_read_regs32(struct thread *td, struct reg32 *regs32)
 185 {
 186
 187         PROC_ACTION(fill_regs32(td, regs32));
 188 }
 189
 190 int
 191 proc_write_regs32(struct thread *td, struct reg32 *regs32)
 192 {
 193
 194         PROC_ACTION(set_regs32(td, regs32));
 195 }
 196
 197 int
 198 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 199 {
 200
 201         PROC_ACTION(fill_dbregs32(td, dbregs32));
 202 }
 203
 204 int
 205 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 206 {
 207
 208         PROC_ACTION(set_dbregs32(td, dbregs32));
 209 }
 210
 211 int
 212 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 213 {
 214
 215         PROC_ACTION(fill_fpregs32(td, fpregs32));
 216 }
 217
 218 int
 219 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 220 {
 221
 222         PROC_ACTION(set_fpregs32(td, fpregs32));
 223 }
 224 #endif
 225
 226 int
 227 proc_sstep(struct thread *td)
 228 {
 229
 230         PROC_ACTION(ptrace_single_step(td));
 231 }
 232
 233 int
 234 proc_rwmem(struct proc *p, struct uio *uio)
 235 {
 236         vm_map_t map;
 237         vm_offset_t pageno;             /* page number */
 238         vm_prot_t reqprot;
 239         int error, fault_flags, page_offset, writing;
 240
 241         /*
 242          * Assert that someone has locked this vmspace.  (Should be
 243          * curthread but we can't assert that.)  This keeps the process
 244          * from exiting out from under us until this operation completes.
 245          */
 246         PROC_ASSERT_HELD(p);
 247         PROC_LOCK_ASSERT(p, MA_NOTOWNED);
 248
 249         /*
 250          * The map we want...
 251          */
 252         map = &p->p_vmspace->vm_map;
 253
 254         /*
 255          * If we are writing, then we request vm_fault() to create a private
 256          * copy of each page.  Since these copies will not be writeable by the
 257          * process, we must explicity request that they be dirtied.
 258          */
 259         writing = uio->uio_rw == UIO_WRITE;
 260         reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
 261         fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL;
 262
 263         /*
 264          * Only map in one page at a time.  We don't have to, but it
 265          * makes things easier.  This way is trivial - right?
 266          */
 267         do {
 268                 vm_offset_t uva;
 269                 u_int len;
 270                 vm_page_t m;
 271
 272                 uva = (vm_offset_t)uio->uio_offset;
 273
 274                 /*
 275                  * Get the page number of this segment.
 276                  */
 277                 pageno = trunc_page(uva);
 278                 page_offset = uva - pageno;
 279
 280                 /*
 281                  * How many bytes to copy
 282                  */
 283                 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
 284
 285                 /*
 286                  * Fault and hold the page on behalf of the process.
 287                  */
 288                 error = vm_fault(map, pageno, reqprot, fault_flags, &m);
 289                 if (error != KERN_SUCCESS) {
 290                         if (error == KERN_RESOURCE_SHORTAGE)
 291                                 error = ENOMEM;
 292                         else
 293                                 error = EFAULT;
 294                         break;
 295                 }
 296
 297                 /*
 298                  * Now do the i/o move.
 299                  */
 300                 error = uiomove_fromphys(&m, page_offset, len, uio);
 301
 302                 /* Make the I-cache coherent for breakpoints. */
 303                 if (writing && error == 0) {
 304                         vm_map_lock_read(map);
 305                         if (vm_map_check_protection(map, pageno, pageno +
 306                             PAGE_SIZE, VM_PROT_EXECUTE))
 307                                 vm_sync_icache(map, uva, len);
 308                         vm_map_unlock_read(map);
 309                 }
 310
 311                 /*
 312                  * Release the page.
 313                  */
 314                 vm_page_unwire(m, PQ_ACTIVE);
 315
 316         } while (error == 0 && uio->uio_resid > 0);
 317
 318         return (error);
 319 }
 320
 321 static ssize_t
 322 proc_iop(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 323     size_t len, enum uio_rw rw)
 324 {
 325         struct iovec iov;
 326         struct uio uio;
 327         ssize_t slen;
 328
 329         MPASS(len < SSIZE_MAX);
 330         slen = (ssize_t)len;
 331
 332         iov.iov_base = (caddr_t)buf;
 333         iov.iov_len = len;
 334         uio.uio_iov = &iov;
 335         uio.uio_iovcnt = 1;
 336         uio.uio_offset = va;
 337         uio.uio_resid = slen;
 338         uio.uio_segflg = UIO_SYSSPACE;
 339         uio.uio_rw = rw;
 340         uio.uio_td = td;
 341         proc_rwmem(p, &uio);
 342         if (uio.uio_resid == slen)
 343                 return (-1);
 344         return (slen - uio.uio_resid);
 345 }
 346
 347 ssize_t
 348 proc_readmem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 349     size_t len)
 350 {
 351
 352         return (proc_iop(td, p, va, buf, len, UIO_READ));
 353 }
 354
 355 ssize_t
 356 proc_writemem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 357     size_t len)
 358 {
 359
 360         return (proc_iop(td, p, va, buf, len, UIO_WRITE));
 361 }
 362
 363 static int
 364 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
 365 {
 366         struct vattr vattr;
 367         vm_map_t map;
 368         vm_map_entry_t entry;
 369         vm_object_t obj, tobj, lobj;
 370         struct vmspace *vm;
 371         struct vnode *vp;
 372         char *freepath, *fullpath;
 373         u_int pathlen;
 374         int error, index;
 375
 376         error = 0;
 377         obj = NULL;
 378
 379         vm = vmspace_acquire_ref(p);
 380         map = &vm->vm_map;
 381         vm_map_lock_read(map);
 382
 383         do {
 384                 KASSERT((map->header.eflags & MAP_ENTRY_IS_SUB_MAP) == 0,
 385                     ("Submap in map header"));
 386                 index = 0;
 387                 VM_MAP_ENTRY_FOREACH(entry, map) {
 388                         if (index >= pve->pve_entry &&
 389                             (entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0)
 390                                 break;
 391                         index++;
 392                 }
 393                 if (index < pve->pve_entry) {
 394                         error = EINVAL;
 395                         break;
 396                 }
 397                 if (entry == &map->header) {
 398                         error = ENOENT;
 399                         break;
 400                 }
 401
 402                 /* We got an entry. */
 403                 pve->pve_entry = index + 1;
 404                 pve->pve_timestamp = map->timestamp;
 405                 pve->pve_start = entry->start;
 406                 pve->pve_end = entry->end - 1;
 407                 pve->pve_offset = entry->offset;
 408                 pve->pve_prot = entry->protection;
 409
 410                 /* Backing object's path needed? */
 411                 if (pve->pve_pathlen == 0)
 412                         break;
 413
 414                 pathlen = pve->pve_pathlen;
 415                 pve->pve_pathlen = 0;
 416
 417                 obj = entry->object.vm_object;
 418                 if (obj != NULL)
 419                         VM_OBJECT_RLOCK(obj);
 420         } while (0);
 421
 422         vm_map_unlock_read(map);
 423
 424         pve->pve_fsid = VNOVAL;
 425         pve->pve_fileid = VNOVAL;
 426
 427         if (error == 0 && obj != NULL) {
 428                 lobj = obj;
 429                 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
 430                         if (tobj != obj)
 431                                 VM_OBJECT_RLOCK(tobj);
 432                         if (lobj != obj)
 433                                 VM_OBJECT_RUNLOCK(lobj);
 434                         lobj = tobj;
 435                         pve->pve_offset += tobj->backing_object_offset;
 436                 }
 437                 vp = vm_object_vnode(lobj);
 438                 if (vp != NULL)
 439                         vref(vp);
 440                 if (lobj != obj)
 441                         VM_OBJECT_RUNLOCK(lobj);
 442                 VM_OBJECT_RUNLOCK(obj);
 443
 444                 if (vp != NULL) {
 445                         freepath = NULL;
 446                         fullpath = NULL;
 447                         vn_fullpath(td, vp, &fullpath, &freepath);
 448                         vn_lock(vp, LK_SHARED | LK_RETRY);
 449                         if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
 450                                 pve->pve_fileid = vattr.va_fileid;
 451                                 pve->pve_fsid = vattr.va_fsid;
 452                         }
 453                         vput(vp);
 454
 455                         if (fullpath != NULL) {
 456                                 pve->pve_pathlen = strlen(fullpath) + 1;
 457                                 if (pve->pve_pathlen <= pathlen) {
 458                                         error = copyout(fullpath, pve->pve_path,
 459                                             pve->pve_pathlen);
 460                                 } else
 461                                         error = ENAMETOOLONG;
 462                         }
 463                         if (freepath != NULL)
 464                                 free(freepath, M_TEMP);
 465                 }
 466         }
 467         vmspace_free(vm);
 468         if (error == 0)
 469                 CTR3(KTR_PTRACE, "PT_VM_ENTRY: pid %d, entry %d, start %p",
 470                     p->p_pid, pve->pve_entry, pve->pve_start);
 471
 472         return (error);
 473 }
 474
 475 #ifdef COMPAT_FREEBSD32
 476 static int
 477 ptrace_vm_entry32(struct thread *td, struct proc *p,
 478     struct ptrace_vm_entry32 *pve32)
 479 {
 480         struct ptrace_vm_entry pve;
 481         int error;
 482
 483         pve.pve_entry = pve32->pve_entry;
 484         pve.pve_pathlen = pve32->pve_pathlen;
 485         pve.pve_path = (void *)(uintptr_t)pve32->pve_path;
 486
 487         error = ptrace_vm_entry(td, p, &pve);
 488         if (error == 0) {
 489                 pve32->pve_entry = pve.pve_entry;
 490                 pve32->pve_timestamp = pve.pve_timestamp;
 491                 pve32->pve_start = pve.pve_start;
 492                 pve32->pve_end = pve.pve_end;
 493                 pve32->pve_offset = pve.pve_offset;
 494                 pve32->pve_prot = pve.pve_prot;
 495                 pve32->pve_fileid = pve.pve_fileid;
 496                 pve32->pve_fsid = pve.pve_fsid;
 497         }
 498
 499         pve32->pve_pathlen = pve.pve_pathlen;
 500         return (error);
 501 }
 502
 503 static void
 504 ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl,
 505     struct ptrace_lwpinfo32 *pl32)
 506 {
 507
 508         bzero(pl32, sizeof(*pl32));
 509         pl32->pl_lwpid = pl->pl_lwpid;
 510         pl32->pl_event = pl->pl_event;
 511         pl32->pl_flags = pl->pl_flags;
 512         pl32->pl_sigmask = pl->pl_sigmask;
 513         pl32->pl_siglist = pl->pl_siglist;
 514         siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo);
 515         strcpy(pl32->pl_tdname, pl->pl_tdname);
 516         pl32->pl_child_pid = pl->pl_child_pid;
 517         pl32->pl_syscall_code = pl->pl_syscall_code;
 518         pl32->pl_syscall_narg = pl->pl_syscall_narg;
 519 }
 520
 521 static void
 522 ptrace_sc_ret_to32(const struct ptrace_sc_ret *psr,
 523     struct ptrace_sc_ret32 *psr32)
 524 {
 525
 526         bzero(psr32, sizeof(*psr32));
 527         psr32->sr_retval[0] = psr->sr_retval[0];
 528         psr32->sr_retval[1] = psr->sr_retval[1];
 529         psr32->sr_error = psr->sr_error;
 530 }
 531 #endif /* COMPAT_FREEBSD32 */
 532
 533 /*
 534  * Process debugging system call.
 535  */
 536 #ifndef _SYS_SYSPROTO_H_
 537 struct ptrace_args {
 538         int     req;
 539         pid_t   pid;
 540         caddr_t addr;
 541         int     data;
 542 };
 543 #endif
 544
 545 #ifdef COMPAT_FREEBSD32
 546 /*
 547  * This CPP subterfuge is to try and reduce the number of ifdefs in
 548  * the body of the code.
 549  *   COPYIN(uap->addr, &r.reg, sizeof r.reg);
 550  * becomes either:
 551  *   copyin(uap->addr, &r.reg, sizeof r.reg);
 552  * or
 553  *   copyin(uap->addr, &r.reg32, sizeof r.reg32);
 554  * .. except this is done at runtime.
 555  */
 556 #define BZERO(a, s)             wrap32 ? \
 557         bzero(a ## 32, s ## 32) : \
 558         bzero(a, s)
 559 #define COPYIN(u, k, s)         wrap32 ? \
 560         copyin(u, k ## 32, s ## 32) : \
 561         copyin(u, k, s)
 562 #define COPYOUT(k, u, s)        wrap32 ? \
 563         copyout(k ## 32, u, s ## 32) : \
 564         copyout(k, u, s)
 565 #else
 566 #define BZERO(a, s)             bzero(a, s)
 567 #define COPYIN(u, k, s)         copyin(u, k, s)
 568 #define COPYOUT(k, u, s)        copyout(k, u, s)
 569 #endif
 570 int
 571 sys_ptrace(struct thread *td, struct ptrace_args *uap)
 572 {
 573         /*
 574          * XXX this obfuscation is to reduce stack usage, but the register
 575          * structs may be too large to put on the stack anyway.
 576          */
 577         union {
 578                 struct ptrace_io_desc piod;
 579                 struct ptrace_lwpinfo pl;
 580                 struct ptrace_vm_entry pve;
 581                 struct dbreg dbreg;
 582                 struct fpreg fpreg;
 583                 struct reg reg;
 584 #ifdef COMPAT_FREEBSD32
 585                 struct dbreg32 dbreg32;
 586                 struct fpreg32 fpreg32;
 587                 struct reg32 reg32;
 588                 struct ptrace_io_desc32 piod32;
 589                 struct ptrace_lwpinfo32 pl32;
 590                 struct ptrace_vm_entry32 pve32;
 591 #endif
 592                 char args[sizeof(td->td_sa.args)];
 593                 struct ptrace_sc_ret psr;
 594                 int ptevents;
 595         } r;
 596         void *addr;
 597         int error = 0;
 598 #ifdef COMPAT_FREEBSD32
 599         int wrap32 = 0;
 600
 601         if (SV_CURPROC_FLAG(SV_ILP32))
 602                 wrap32 = 1;
 603 #endif
 604         AUDIT_ARG_PID(uap->pid);
 605         AUDIT_ARG_CMD(uap->req);
 606         AUDIT_ARG_VALUE(uap->data);
 607         addr = &r;
 608         switch (uap->req) {
 609         case PT_GET_EVENT_MASK:
 610         case PT_LWPINFO:
 611         case PT_GET_SC_ARGS:
 612         case PT_GET_SC_RET:
 613                 break;
 614         case PT_GETREGS:
 615                 BZERO(&r.reg, sizeof r.reg);
 616                 break;
 617         case PT_GETFPREGS:
 618                 BZERO(&r.fpreg, sizeof r.fpreg);
 619                 break;
 620         case PT_GETDBREGS:
 621                 BZERO(&r.dbreg, sizeof r.dbreg);
 622                 break;
 623         case PT_SETREGS:
 624                 error = COPYIN(uap->addr, &r.reg, sizeof r.reg);
 625                 break;
 626         case PT_SETFPREGS:
 627                 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg);
 628                 break;
 629         case PT_SETDBREGS:
 630                 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg);
 631                 break;
 632         case PT_SET_EVENT_MASK:
 633                 if (uap->data != sizeof(r.ptevents))
 634                         error = EINVAL;
 635                 else
 636                         error = copyin(uap->addr, &r.ptevents, uap->data);
 637                 break;
 638         case PT_IO:
 639                 error = COPYIN(uap->addr, &r.piod, sizeof r.piod);
 640                 break;
 641         case PT_VM_ENTRY:
 642                 error = COPYIN(uap->addr, &r.pve, sizeof r.pve);
 643                 break;
 644         default:
 645                 addr = uap->addr;
 646                 break;
 647         }
 648         if (error)
 649                 return (error);
 650
 651         error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
 652         if (error)
 653                 return (error);
 654
 655         switch (uap->req) {
 656         case PT_VM_ENTRY:
 657                 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve);
 658                 break;
 659         case PT_IO:
 660                 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod);
 661                 break;
 662         case PT_GETREGS:
 663                 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg);
 664                 break;
 665         case PT_GETFPREGS:
 666                 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg);
 667                 break;
 668         case PT_GETDBREGS:
 669                 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg);
 670                 break;
 671         case PT_GET_EVENT_MASK:
 672                 /* NB: The size in uap->data is validated in kern_ptrace(). */
 673                 error = copyout(&r.ptevents, uap->addr, uap->data);
 674                 break;
 675         case PT_LWPINFO:
 676                 /* NB: The size in uap->data is validated in kern_ptrace(). */
 677                 error = copyout(&r.pl, uap->addr, uap->data);
 678                 break;
 679         case PT_GET_SC_ARGS:
 680                 error = copyout(r.args, uap->addr, MIN(uap->data,
 681                     sizeof(r.args)));
 682                 break;
 683         case PT_GET_SC_RET:
 684                 error = copyout(&r.psr, uap->addr, MIN(uap->data,
 685                     sizeof(r.psr)));
 686                 break;
 687         }
 688
 689         return (error);
 690 }
 691 #undef COPYIN
 692 #undef COPYOUT
 693 #undef BZERO
 694
 695 #ifdef COMPAT_FREEBSD32
 696 /*
 697  *   PROC_READ(regs, td2, addr);
 698  * becomes either:
 699  *   proc_read_regs(td2, addr);
 700  * or
 701  *   proc_read_regs32(td2, addr);
 702  * .. except this is done at runtime.  There is an additional
 703  * complication in that PROC_WRITE disallows 32 bit consumers
 704  * from writing to 64 bit address space targets.
 705  */
 706 #define PROC_READ(w, t, a)      wrap32 ? \
 707         proc_read_ ## w ## 32(t, a) : \
 708         proc_read_ ## w (t, a)
 709 #define PROC_WRITE(w, t, a)     wrap32 ? \
 710         (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
 711         proc_write_ ## w (t, a)
 712 #else
 713 #define PROC_READ(w, t, a)      proc_read_ ## w (t, a)
 714 #define PROC_WRITE(w, t, a)     proc_write_ ## w (t, a)
 715 #endif
 716
 717 void
 718 proc_set_traced(struct proc *p, bool stop)
 719 {
 720
 721         sx_assert(&proctree_lock, SX_XLOCKED);
 722         PROC_LOCK_ASSERT(p, MA_OWNED);
 723         p->p_flag |= P_TRACED;
 724         if (stop)
 725                 p->p_flag2 |= P2_PTRACE_FSTP;
 726         p->p_ptevents = PTRACE_DEFAULT;
 727 }
 728
 729 int
 730 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 731 {
 732         struct iovec iov;
 733         struct uio uio;
 734         struct proc *curp, *p, *pp;
 735         struct thread *td2 = NULL, *td3;
 736         struct ptrace_io_desc *piod = NULL;
 737         struct ptrace_lwpinfo *pl;
 738         struct ptrace_sc_ret *psr;
 739         int error, num, tmp;
 740         int proctree_locked = 0;
 741         lwpid_t tid = 0, *buf;
 742 #ifdef COMPAT_FREEBSD32
 743         int wrap32 = 0, safe = 0;
 744         struct ptrace_io_desc32 *piod32 = NULL;
 745         struct ptrace_lwpinfo32 *pl32 = NULL;
 746         struct ptrace_sc_ret32 *psr32 = NULL;
 747         union {
 748                 struct ptrace_lwpinfo pl;
 749                 struct ptrace_sc_ret psr;
 750         } r;
 751 #endif
 752
 753         curp = td->td_proc;
 754
 755         /* Lock proctree before locking the process. */
 756         switch (req) {
 757         case PT_TRACE_ME:
 758         case PT_ATTACH:
 759         case PT_STEP:
 760         case PT_CONTINUE:
 761         case PT_TO_SCE:
 762         case PT_TO_SCX:
 763         case PT_SYSCALL:
 764         case PT_FOLLOW_FORK:
 765         case PT_LWP_EVENTS:
 766         case PT_GET_EVENT_MASK:
 767         case PT_SET_EVENT_MASK:
 768         case PT_DETACH:
 769         case PT_GET_SC_ARGS:
 770                 sx_xlock(&proctree_lock);
 771                 proctree_locked = 1;
 772                 break;
 773         default:
 774                 break;
 775         }
 776
 777         if (req == PT_TRACE_ME) {
 778                 p = td->td_proc;
 779                 PROC_LOCK(p);
 780         } else {
 781                 if (pid <= PID_MAX) {
 782                         if ((p = pfind(pid)) == NULL) {
 783                                 if (proctree_locked)
 784                                         sx_xunlock(&proctree_lock);
 785                                 return (ESRCH);
 786                         }
 787                 } else {
 788                         td2 = tdfind(pid, -1);
 789                         if (td2 == NULL) {
 790                                 if (proctree_locked)
 791                                         sx_xunlock(&proctree_lock);
 792                                 return (ESRCH);
 793                         }
 794                         p = td2->td_proc;
 795                         tid = pid;
 796                         pid = p->p_pid;
 797                 }
 798         }
 799         AUDIT_ARG_PROCESS(p);
 800
 801         if ((p->p_flag & P_WEXIT) != 0) {
 802                 error = ESRCH;
 803                 goto fail;
 804         }
 805         if ((error = p_cansee(td, p)) != 0)
 806                 goto fail;
 807
 808         if ((error = p_candebug(td, p)) != 0)
 809                 goto fail;
 810
 811         /*
 812          * System processes can't be debugged.
 813          */
 814         if ((p->p_flag & P_SYSTEM) != 0) {
 815                 error = EINVAL;
 816                 goto fail;
 817         }
 818
 819         if (tid == 0) {
 820                 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
 821                         KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
 822                         td2 = p->p_xthread;
 823                 } else {
 824                         td2 = FIRST_THREAD_IN_PROC(p);
 825                 }
 826                 tid = td2->td_tid;
 827         }
 828
 829 #ifdef COMPAT_FREEBSD32
 830         /*
 831          * Test if we're a 32 bit client and what the target is.
 832          * Set the wrap controls accordingly.
 833          */
 834         if (SV_CURPROC_FLAG(SV_ILP32)) {
 835                 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32))
 836                         safe = 1;
 837                 wrap32 = 1;
 838         }
 839 #endif
 840         /*
 841          * Permissions check
 842          */
 843         switch (req) {
 844         case PT_TRACE_ME:
 845                 /*
 846                  * Always legal, when there is a parent process which
 847                  * could trace us.  Otherwise, reject.
 848                  */
 849                 if ((p->p_flag & P_TRACED) != 0) {
 850                         error = EBUSY;
 851                         goto fail;
 852                 }
 853                 if (p->p_pptr == initproc) {
 854                         error = EPERM;
 855                         goto fail;
 856                 }
 857                 break;
 858
 859         case PT_ATTACH:
 860                 /* Self */
 861                 if (p == td->td_proc) {
 862                         error = EINVAL;
 863                         goto fail;
 864                 }
 865
 866                 /* Already traced */
 867                 if (p->p_flag & P_TRACED) {
 868                         error = EBUSY;
 869                         goto fail;
 870                 }
 871
 872                 /* Can't trace an ancestor if you're being traced. */
 873                 if (curp->p_flag & P_TRACED) {
 874                         for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
 875                                 if (pp == p) {
 876                                         error = EINVAL;
 877                                         goto fail;
 878                                 }
 879                         }
 880                 }
 881
 882                 /* OK */
 883                 break;
 884
 885         case PT_CLEARSTEP:
 886                 /* Allow thread to clear single step for itself */
 887                 if (td->td_tid == tid)
 888                         break;
 889
 890                 /* FALLTHROUGH */
 891         default:
 892                 /* not being traced... */
 893                 if ((p->p_flag & P_TRACED) == 0) {
 894                         error = EPERM;
 895                         goto fail;
 896                 }
 897
 898                 /* not being traced by YOU */
 899                 if (p->p_pptr != td->td_proc) {
 900                         error = EBUSY;
 901                         goto fail;
 902                 }
 903
 904                 /* not currently stopped */
 905                 if ((p->p_flag & P_STOPPED_TRACE) == 0 ||
 906                     p->p_suspcount != p->p_numthreads  ||
 907                     (p->p_flag & P_WAITED) == 0) {
 908                         error = EBUSY;
 909                         goto fail;
 910                 }
 911
 912                 /* OK */
 913                 break;
 914         }
 915
 916         /* Keep this process around until we finish this request. */
 917         _PHOLD(p);
 918
 919 #ifdef FIX_SSTEP
 920         /*
 921          * Single step fixup ala procfs
 922          */
 923         FIX_SSTEP(td2);
 924 #endif
 925
 926         /*
 927          * Actually do the requests
 928          */
 929
 930         td->td_retval[0] = 0;
 931
 932         switch (req) {
 933         case PT_TRACE_ME:
 934                 /* set my trace flag and "owner" so it can read/write me */
 935                 proc_set_traced(p, false);
 936                 if (p->p_flag & P_PPWAIT)
 937                         p->p_flag |= P_PPTRACE;
 938                 CTR1(KTR_PTRACE, "PT_TRACE_ME: pid %d", p->p_pid);
 939                 break;
 940
 941         case PT_ATTACH:
 942                 /* security check done above */
 943                 /*
 944                  * It would be nice if the tracing relationship was separate
 945                  * from the parent relationship but that would require
 946                  * another set of links in the proc struct or for "wait"
 947                  * to scan the entire proc table.  To make life easier,
 948                  * we just re-parent the process we're trying to trace.
 949                  * The old parent is remembered so we can put things back
 950                  * on a "detach".
 951                  */
 952                 proc_set_traced(p, true);
 953                 proc_reparent(p, td->td_proc, false);
 954                 CTR2(KTR_PTRACE, "PT_ATTACH: pid %d, oppid %d", p->p_pid,
 955                     p->p_oppid);
 956
 957                 sx_xunlock(&proctree_lock);
 958                 proctree_locked = 0;
 959                 MPASS(p->p_xthread == NULL);
 960                 MPASS((p->p_flag & P_STOPPED_TRACE) == 0);
 961
 962                 /*
 963                  * If already stopped due to a stop signal, clear the
 964                  * existing stop before triggering a traced SIGSTOP.
 965                  */
 966                 if ((p->p_flag & P_STOPPED_SIG) != 0) {
 967                         PROC_SLOCK(p);
 968                         p->p_flag &= ~(P_STOPPED_SIG | P_WAITED);
 969                         thread_unsuspend(p);
 970                         PROC_SUNLOCK(p);
 971                 }
 972
 973                 kern_psignal(p, SIGSTOP);
 974                 break;
 975
 976         case PT_CLEARSTEP:
 977                 CTR2(KTR_PTRACE, "PT_CLEARSTEP: tid %d (pid %d)", td2->td_tid,
 978                     p->p_pid);
 979                 error = ptrace_clear_single_step(td2);
 980                 break;
 981
 982         case PT_SETSTEP:
 983                 CTR2(KTR_PTRACE, "PT_SETSTEP: tid %d (pid %d)", td2->td_tid,
 984                     p->p_pid);
 985                 error = ptrace_single_step(td2);
 986                 break;
 987
 988         case PT_SUSPEND:
 989                 CTR2(KTR_PTRACE, "PT_SUSPEND: tid %d (pid %d)", td2->td_tid,
 990                     p->p_pid);
 991                 td2->td_dbgflags |= TDB_SUSPEND;
 992                 thread_lock(td2);
 993                 td2->td_flags |= TDF_NEEDSUSPCHK;
 994                 thread_unlock(td2);
 995                 break;
 996
 997         case PT_RESUME:
 998                 CTR2(KTR_PTRACE, "PT_RESUME: tid %d (pid %d)", td2->td_tid,
 999                     p->p_pid);
1000                 td2->td_dbgflags &= ~TDB_SUSPEND;
1001                 break;
1002
1003         case PT_FOLLOW_FORK:
1004                 CTR3(KTR_PTRACE, "PT_FOLLOW_FORK: pid %d %s -> %s", p->p_pid,
1005                     p->p_ptevents & PTRACE_FORK ? "enabled" : "disabled",
1006                     data ? "enabled" : "disabled");
1007                 if (data)
1008                         p->p_ptevents |= PTRACE_FORK;
1009                 else
1010                         p->p_ptevents &= ~PTRACE_FORK;
1011                 break;
1012
1013         case PT_LWP_EVENTS:
1014                 CTR3(KTR_PTRACE, "PT_LWP_EVENTS: pid %d %s -> %s", p->p_pid,
1015                     p->p_ptevents & PTRACE_LWP ? "enabled" : "disabled",
1016                     data ? "enabled" : "disabled");
1017                 if (data)
1018                         p->p_ptevents |= PTRACE_LWP;
1019                 else
1020                         p->p_ptevents &= ~PTRACE_LWP;
1021                 break;
1022
1023         case PT_GET_EVENT_MASK:
1024                 if (data != sizeof(p->p_ptevents)) {
1025                         error = EINVAL;
1026                         break;
1027                 }
1028                 CTR2(KTR_PTRACE, "PT_GET_EVENT_MASK: pid %d mask %#x", p->p_pid,
1029                     p->p_ptevents);
1030                 *(int *)addr = p->p_ptevents;
1031                 break;
1032
1033         case PT_SET_EVENT_MASK:
1034                 if (data != sizeof(p->p_ptevents)) {
1035                         error = EINVAL;
1036                         break;
1037                 }
1038                 tmp = *(int *)addr;
1039                 if ((tmp & ~(PTRACE_EXEC | PTRACE_SCE | PTRACE_SCX |
1040                     PTRACE_FORK | PTRACE_LWP | PTRACE_VFORK)) != 0) {
1041                         error = EINVAL;
1042                         break;
1043                 }
1044                 CTR3(KTR_PTRACE, "PT_SET_EVENT_MASK: pid %d mask %#x -> %#x",
1045                     p->p_pid, p->p_ptevents, tmp);
1046                 p->p_ptevents = tmp;
1047                 break;
1048
1049         case PT_GET_SC_ARGS:
1050                 CTR1(KTR_PTRACE, "PT_GET_SC_ARGS: pid %d", p->p_pid);
1051                 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) == 0
1052 #ifdef COMPAT_FREEBSD32
1053                     || (wrap32 && !safe)
1054 #endif
1055                     ) {
1056                         error = EINVAL;
1057                         break;
1058                 }
1059                 bzero(addr, sizeof(td2->td_sa.args));
1060 #ifdef COMPAT_FREEBSD32
1061                 if (wrap32)
1062                         for (num = 0; num < nitems(td2->td_sa.args); num++)
1063                                 ((uint32_t *)addr)[num] = (uint32_t)
1064                                     td2->td_sa.args[num];
1065                 else
1066 #endif
1067                         bcopy(td2->td_sa.args, addr, td2->td_sa.narg *
1068                             sizeof(register_t));
1069                 break;
1070
1071         case PT_GET_SC_RET:
1072                 if ((td2->td_dbgflags & (TDB_SCX)) == 0
1073 #ifdef COMPAT_FREEBSD32
1074                     || (wrap32 && !safe)
1075 #endif
1076                     ) {
1077                         error = EINVAL;
1078                         break;
1079                 }
1080 #ifdef COMPAT_FREEBSD32
1081                 if (wrap32) {
1082                         psr = &r.psr;
1083                         psr32 = addr;
1084                 } else
1085 #endif
1086                 psr = addr;
1087                 bzero(psr, sizeof(*psr));
1088                 psr->sr_error = td2->td_errno;
1089                 if (psr->sr_error == 0) {
1090                         psr->sr_retval[0] = td2->td_retval[0];
1091                         psr->sr_retval[1] = td2->td_retval[1];
1092                 }
1093 #ifdef COMPAT_FREEBSD32
1094                 if (wrap32)
1095                         ptrace_sc_ret_to32(psr, psr32);
1096 #endif
1097                 CTR4(KTR_PTRACE,
1098                     "PT_GET_SC_RET: pid %d error %d retval %#lx,%#lx",
1099                     p->p_pid, psr->sr_error, psr->sr_retval[0],
1100                     psr->sr_retval[1]);
1101                 break;
1102
1103         case PT_STEP:
1104         case PT_CONTINUE:
1105         case PT_TO_SCE:
1106         case PT_TO_SCX:
1107         case PT_SYSCALL:
1108         case PT_DETACH:
1109                 /* Zero means do not send any signal */
1110                 if (data < 0 || data > _SIG_MAXSIG) {
1111                         error = EINVAL;
1112                         break;
1113                 }
1114
1115                 switch (req) {
1116                 case PT_STEP:
1117                         CTR3(KTR_PTRACE, "PT_STEP: tid %d (pid %d), sig = %d",
1118                             td2->td_tid, p->p_pid, data);
1119                         error = ptrace_single_step(td2);
1120                         if (error)
1121                                 goto out;
1122                         break;
1123                 case PT_CONTINUE:
1124                 case PT_TO_SCE:
1125                 case PT_TO_SCX:
1126                 case PT_SYSCALL:
1127                         if (addr != (void *)1) {
1128                                 error = ptrace_set_pc(td2,
1129                                     (u_long)(uintfptr_t)addr);
1130                                 if (error)
1131                                         goto out;
1132                         }
1133                         switch (req) {
1134                         case PT_TO_SCE:
1135                                 p->p_ptevents |= PTRACE_SCE;
1136                                 CTR4(KTR_PTRACE,
1137                     "PT_TO_SCE: pid %d, events = %#x, PC = %#lx, sig = %d",
1138                                     p->p_pid, p->p_ptevents,
1139                                     (u_long)(uintfptr_t)addr, data);
1140                                 break;
1141                         case PT_TO_SCX:
1142                                 p->p_ptevents |= PTRACE_SCX;
1143                                 CTR4(KTR_PTRACE,
1144                     "PT_TO_SCX: pid %d, events = %#x, PC = %#lx, sig = %d",
1145                                     p->p_pid, p->p_ptevents,
1146                                     (u_long)(uintfptr_t)addr, data);
1147                                 break;
1148                         case PT_SYSCALL:
1149                                 p->p_ptevents |= PTRACE_SYSCALL;
1150                                 CTR4(KTR_PTRACE,
1151                     "PT_SYSCALL: pid %d, events = %#x, PC = %#lx, sig = %d",
1152                                     p->p_pid, p->p_ptevents,
1153                                     (u_long)(uintfptr_t)addr, data);
1154                                 break;
1155                         case PT_CONTINUE:
1156                                 CTR3(KTR_PTRACE,
1157                                     "PT_CONTINUE: pid %d, PC = %#lx, sig = %d",
1158                                     p->p_pid, (u_long)(uintfptr_t)addr, data);
1159                                 break;
1160                         }
1161                         break;
1162                 case PT_DETACH:
1163                         /*
1164                          * Reset the process parent.
1165                          *
1166                          * NB: This clears P_TRACED before reparenting
1167                          * a detached process back to its original
1168                          * parent.  Otherwise the debugee will be set
1169                          * as an orphan of the debugger.
1170                          */
1171                         p->p_flag &= ~(P_TRACED | P_WAITED);
1172                         if (p->p_oppid != p->p_pptr->p_pid) {
1173                                 PROC_LOCK(p->p_pptr);
1174                                 sigqueue_take(p->p_ksi);
1175                                 PROC_UNLOCK(p->p_pptr);
1176
1177                                 pp = proc_realparent(p);
1178                                 proc_reparent(p, pp, false);
1179                                 if (pp == initproc)
1180                                         p->p_sigparent = SIGCHLD;
1181                                 CTR3(KTR_PTRACE,
1182                             "PT_DETACH: pid %d reparented to pid %d, sig %d",
1183                                     p->p_pid, pp->p_pid, data);
1184                         } else
1185                                 CTR2(KTR_PTRACE, "PT_DETACH: pid %d, sig %d",
1186                                     p->p_pid, data);
1187                         p->p_ptevents = 0;
1188                         FOREACH_THREAD_IN_PROC(p, td3) {
1189                                 if ((td3->td_dbgflags & TDB_FSTP) != 0) {
1190                                         sigqueue_delete(&td3->td_sigqueue,
1191                                             SIGSTOP);
1192                                 }
1193                                 td3->td_dbgflags &= ~(TDB_XSIG | TDB_FSTP |
1194                                     TDB_SUSPEND);
1195                         }
1196
1197                         if ((p->p_flag2 & P2_PTRACE_FSTP) != 0) {
1198                                 sigqueue_delete(&p->p_sigqueue, SIGSTOP);
1199                                 p->p_flag2 &= ~P2_PTRACE_FSTP;
1200                         }
1201
1202                         /* should we send SIGCHLD? */
1203                         /* childproc_continued(p); */
1204                         break;
1205                 }
1206
1207                 sx_xunlock(&proctree_lock);
1208                 proctree_locked = 0;
1209
1210         sendsig:
1211                 MPASS(proctree_locked == 0);
1212
1213                 /*
1214                  * Clear the pending event for the thread that just
1215                  * reported its event (p_xthread).  This may not be
1216                  * the thread passed to PT_CONTINUE, PT_STEP, etc. if
1217                  * the debugger is resuming a different thread.
1218                  *
1219                  * Deliver any pending signal via the reporting thread.
1220                  */
1221                 MPASS(p->p_xthread != NULL);
1222                 p->p_xthread->td_dbgflags &= ~TDB_XSIG;
1223                 p->p_xthread->td_xsig = data;
1224                 p->p_xthread = NULL;
1225                 p->p_xsig = data;
1226
1227                 /*
1228                  * P_WKILLED is insurance that a PT_KILL/SIGKILL
1229                  * always works immediately, even if another thread is
1230                  * unsuspended first and attempts to handle a
1231                  * different signal or if the POSIX.1b style signal
1232                  * queue cannot accommodate any new signals.
1233                  */
1234                 if (data == SIGKILL)
1235                         proc_wkilled(p);
1236
1237                 /*
1238                  * Unsuspend all threads.  To leave a thread
1239                  * suspended, use PT_SUSPEND to suspend it before
1240                  * continuing the process.
1241                  */
1242                 PROC_SLOCK(p);
1243                 p->p_flag &= ~(P_STOPPED_TRACE | P_STOPPED_SIG | P_WAITED);
1244                 thread_unsuspend(p);
1245                 PROC_SUNLOCK(p);
1246                 break;
1247
1248         case PT_WRITE_I:
1249         case PT_WRITE_D:
1250                 td2->td_dbgflags |= TDB_USERWR;
1251                 PROC_UNLOCK(p);
1252                 error = 0;
1253                 if (proc_writemem(td, p, (off_t)(uintptr_t)addr, &data,
1254                     sizeof(int)) != sizeof(int))
1255                         error = ENOMEM;
1256                 else
1257                         CTR3(KTR_PTRACE, "PT_WRITE: pid %d: %p <= %#x",
1258                             p->p_pid, addr, data);
1259                 PROC_LOCK(p);
1260                 break;
1261
1262         case PT_READ_I:
1263         case PT_READ_D:
1264                 PROC_UNLOCK(p);
1265                 error = tmp = 0;
1266                 if (proc_readmem(td, p, (off_t)(uintptr_t)addr, &tmp,
1267                     sizeof(int)) != sizeof(int))
1268                         error = ENOMEM;
1269                 else
1270                         CTR3(KTR_PTRACE, "PT_READ: pid %d: %p >= %#x",
1271                             p->p_pid, addr, tmp);
1272                 td->td_retval[0] = tmp;
1273                 PROC_LOCK(p);
1274                 break;
1275
1276         case PT_IO:
1277 #ifdef COMPAT_FREEBSD32
1278                 if (wrap32) {
1279                         piod32 = addr;
1280                         iov.iov_base = (void *)(uintptr_t)piod32->piod_addr;
1281                         iov.iov_len = piod32->piod_len;
1282                         uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs;
1283                         uio.uio_resid = piod32->piod_len;
1284                 } else
1285 #endif
1286                 {
1287                         piod = addr;
1288                         iov.iov_base = piod->piod_addr;
1289                         iov.iov_len = piod->piod_len;
1290                         uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
1291                         uio.uio_resid = piod->piod_len;
1292                 }
1293                 uio.uio_iov = &iov;
1294                 uio.uio_iovcnt = 1;
1295                 uio.uio_segflg = UIO_USERSPACE;
1296                 uio.uio_td = td;
1297 #ifdef COMPAT_FREEBSD32
1298                 tmp = wrap32 ? piod32->piod_op : piod->piod_op;
1299 #else
1300                 tmp = piod->piod_op;
1301 #endif
1302                 switch (tmp) {
1303                 case PIOD_READ_D:
1304                 case PIOD_READ_I:
1305                         CTR3(KTR_PTRACE, "PT_IO: pid %d: READ (%p, %#x)",
1306                             p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1307                         uio.uio_rw = UIO_READ;
1308                         break;
1309                 case PIOD_WRITE_D:
1310                 case PIOD_WRITE_I:
1311                         CTR3(KTR_PTRACE, "PT_IO: pid %d: WRITE (%p, %#x)",
1312                             p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1313                         td2->td_dbgflags |= TDB_USERWR;
1314                         uio.uio_rw = UIO_WRITE;
1315                         break;
1316                 default:
1317                         error = EINVAL;
1318                         goto out;
1319                 }
1320                 PROC_UNLOCK(p);
1321                 error = proc_rwmem(p, &uio);
1322 #ifdef COMPAT_FREEBSD32
1323                 if (wrap32)
1324                         piod32->piod_len -= uio.uio_resid;
1325                 else
1326 #endif
1327                         piod->piod_len -= uio.uio_resid;
1328                 PROC_LOCK(p);
1329                 break;
1330
1331         case PT_KILL:
1332                 CTR1(KTR_PTRACE, "PT_KILL: pid %d", p->p_pid);
1333                 data = SIGKILL;
1334                 goto sendsig;   /* in PT_CONTINUE above */
1335
1336         case PT_SETREGS:
1337                 CTR2(KTR_PTRACE, "PT_SETREGS: tid %d (pid %d)", td2->td_tid,
1338                     p->p_pid);
1339                 td2->td_dbgflags |= TDB_USERWR;
1340                 error = PROC_WRITE(regs, td2, addr);
1341                 break;
1342
1343         case PT_GETREGS:
1344                 CTR2(KTR_PTRACE, "PT_GETREGS: tid %d (pid %d)", td2->td_tid,
1345                     p->p_pid);
1346                 error = PROC_READ(regs, td2, addr);
1347                 break;
1348
1349         case PT_SETFPREGS:
1350                 CTR2(KTR_PTRACE, "PT_SETFPREGS: tid %d (pid %d)", td2->td_tid,
1351                     p->p_pid);
1352                 td2->td_dbgflags |= TDB_USERWR;
1353                 error = PROC_WRITE(fpregs, td2, addr);
1354                 break;
1355
1356         case PT_GETFPREGS:
1357                 CTR2(KTR_PTRACE, "PT_GETFPREGS: tid %d (pid %d)", td2->td_tid,
1358                     p->p_pid);
1359                 error = PROC_READ(fpregs, td2, addr);
1360                 break;
1361
1362         case PT_SETDBREGS:
1363                 CTR2(KTR_PTRACE, "PT_SETDBREGS: tid %d (pid %d)", td2->td_tid,
1364                     p->p_pid);
1365                 td2->td_dbgflags |= TDB_USERWR;
1366                 error = PROC_WRITE(dbregs, td2, addr);
1367                 break;
1368
1369         case PT_GETDBREGS:
1370                 CTR2(KTR_PTRACE, "PT_GETDBREGS: tid %d (pid %d)", td2->td_tid,
1371                     p->p_pid);
1372                 error = PROC_READ(dbregs, td2, addr);
1373                 break;
1374
1375         case PT_LWPINFO:
1376                 if (data <= 0 ||
1377 #ifdef COMPAT_FREEBSD32
1378                     (!wrap32 && data > sizeof(*pl)) ||
1379                     (wrap32 && data > sizeof(*pl32))) {
1380 #else
1381                     data > sizeof(*pl)) {
1382 #endif
1383                         error = EINVAL;
1384                         break;
1385                 }
1386 #ifdef COMPAT_FREEBSD32
1387                 if (wrap32) {
1388                         pl = &r.pl;
1389                         pl32 = addr;
1390                 } else
1391 #endif
1392                 pl = addr;
1393                 bzero(pl, sizeof(*pl));
1394                 pl->pl_lwpid = td2->td_tid;
1395                 pl->pl_event = PL_EVENT_NONE;
1396                 pl->pl_flags = 0;
1397                 if (td2->td_dbgflags & TDB_XSIG) {
1398                         pl->pl_event = PL_EVENT_SIGNAL;
1399                         if (td2->td_si.si_signo != 0 &&
1400 #ifdef COMPAT_FREEBSD32
1401                             ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo,
1402                             pl_siginfo) + sizeof(pl->pl_siginfo)) ||
1403                             (wrap32 && data >= offsetof(struct ptrace_lwpinfo32,
1404                             pl_siginfo) + sizeof(struct siginfo32)))
1405 #else
1406                             data >= offsetof(struct ptrace_lwpinfo, pl_siginfo)
1407                             + sizeof(pl->pl_siginfo)
1408 #endif
1409                         ){
1410                                 pl->pl_flags |= PL_FLAG_SI;
1411                                 pl->pl_siginfo = td2->td_si;
1412                         }
1413                 }
1414                 if (td2->td_dbgflags & TDB_SCE)
1415                         pl->pl_flags |= PL_FLAG_SCE;
1416                 else if (td2->td_dbgflags & TDB_SCX)
1417                         pl->pl_flags |= PL_FLAG_SCX;
1418                 if (td2->td_dbgflags & TDB_EXEC)
1419                         pl->pl_flags |= PL_FLAG_EXEC;
1420                 if (td2->td_dbgflags & TDB_FORK) {
1421                         pl->pl_flags |= PL_FLAG_FORKED;
1422                         pl->pl_child_pid = td2->td_dbg_forked;
1423                         if (td2->td_dbgflags & TDB_VFORK)
1424                                 pl->pl_flags |= PL_FLAG_VFORKED;
1425                 } else if ((td2->td_dbgflags & (TDB_SCX | TDB_VFORK)) ==
1426                     TDB_VFORK)
1427                         pl->pl_flags |= PL_FLAG_VFORK_DONE;
1428                 if (td2->td_dbgflags & TDB_CHILD)
1429                         pl->pl_flags |= PL_FLAG_CHILD;
1430                 if (td2->td_dbgflags & TDB_BORN)
1431                         pl->pl_flags |= PL_FLAG_BORN;
1432                 if (td2->td_dbgflags & TDB_EXIT)
1433                         pl->pl_flags |= PL_FLAG_EXITED;
1434                 pl->pl_sigmask = td2->td_sigmask;
1435                 pl->pl_siglist = td2->td_siglist;
1436                 strcpy(pl->pl_tdname, td2->td_name);
1437                 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) != 0) {
1438                         pl->pl_syscall_code = td2->td_sa.code;
1439                         pl->pl_syscall_narg = td2->td_sa.narg;
1440                 } else {
1441                         pl->pl_syscall_code = 0;
1442                         pl->pl_syscall_narg = 0;
1443                 }
1444 #ifdef COMPAT_FREEBSD32
1445                 if (wrap32)
1446                         ptrace_lwpinfo_to32(pl, pl32);
1447 #endif
1448                 CTR6(KTR_PTRACE,
1449     "PT_LWPINFO: tid %d (pid %d) event %d flags %#x child pid %d syscall %d",
1450                     td2->td_tid, p->p_pid, pl->pl_event, pl->pl_flags,
1451                     pl->pl_child_pid, pl->pl_syscall_code);
1452                 break;
1453
1454         case PT_GETNUMLWPS:
1455                 CTR2(KTR_PTRACE, "PT_GETNUMLWPS: pid %d: %d threads", p->p_pid,
1456                     p->p_numthreads);
1457                 td->td_retval[0] = p->p_numthreads;
1458                 break;
1459
1460         case PT_GETLWPLIST:
1461                 CTR3(KTR_PTRACE, "PT_GETLWPLIST: pid %d: data %d, actual %d",
1462                     p->p_pid, data, p->p_numthreads);
1463                 if (data <= 0) {
1464                         error = EINVAL;
1465                         break;
1466                 }
1467                 num = imin(p->p_numthreads, data);
1468                 PROC_UNLOCK(p);
1469                 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
1470                 tmp = 0;
1471                 PROC_LOCK(p);
1472                 FOREACH_THREAD_IN_PROC(p, td2) {
1473                         if (tmp >= num)
1474                                 break;
1475                         buf[tmp++] = td2->td_tid;
1476                 }
1477                 PROC_UNLOCK(p);
1478                 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
1479                 free(buf, M_TEMP);
1480                 if (!error)
1481                         td->td_retval[0] = tmp;
1482                 PROC_LOCK(p);
1483                 break;
1484
1485         case PT_VM_TIMESTAMP:
1486                 CTR2(KTR_PTRACE, "PT_VM_TIMESTAMP: pid %d: timestamp %d",
1487                     p->p_pid, p->p_vmspace->vm_map.timestamp);
1488                 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
1489                 break;
1490
1491         case PT_VM_ENTRY:
1492                 PROC_UNLOCK(p);
1493 #ifdef COMPAT_FREEBSD32
1494                 if (wrap32)
1495                         error = ptrace_vm_entry32(td, p, addr);
1496                 else
1497 #endif
1498                 error = ptrace_vm_entry(td, p, addr);
1499                 PROC_LOCK(p);
1500                 break;
1501
1502         default:
1503 #ifdef __HAVE_PTRACE_MACHDEP
1504                 if (req >= PT_FIRSTMACH) {
1505                         PROC_UNLOCK(p);
1506                         error = cpu_ptrace(td2, req, addr, data);
1507                         PROC_LOCK(p);
1508                 } else
1509 #endif
1510                         /* Unknown request. */
1511                         error = EINVAL;
1512                 break;
1513         }
1514
1515 out:
1516         /* Drop our hold on this process now that the request has completed. */
1517         _PRELE(p);
1518 fail:
1519         PROC_UNLOCK(p);
1520         if (proctree_locked)
1521                 sx_xunlock(&proctree_lock);
1522         return (error);
1523 }
1524 #undef PROC_READ
1525 #undef PROC_WRITE