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/pioctl.h>
  47 #include <sys/priv.h>
  48 #include <sys/proc.h>
  49 #include <sys/vnode.h>
  50 #include <sys/ptrace.h>
  51 #include <sys/rwlock.h>
  52 #include <sys/sx.h>
  53 #include <sys/malloc.h>
  54 #include <sys/signalvar.h>
  55
  56 #include <machine/reg.h>
  57
  58 #include <security/audit/audit.h>
  59
  60 #include <vm/vm.h>
  61 #include <vm/pmap.h>
  62 #include <vm/vm_extern.h>
  63 #include <vm/vm_map.h>
  64 #include <vm/vm_kern.h>
  65 #include <vm/vm_object.h>
  66 #include <vm/vm_page.h>
  67 #include <vm/vm_param.h>
  68
  69 #ifdef COMPAT_FREEBSD32
  70 #include <sys/procfs.h>
  71 #include <compat/freebsd32/freebsd32_signal.h>
  72
  73 struct ptrace_io_desc32 {
  74         int             piod_op;
  75         uint32_t        piod_offs;
  76         uint32_t        piod_addr;
  77         uint32_t        piod_len;
  78 };
  79
  80 struct ptrace_sc_ret32 {
  81         uint32_t        sr_retval[2];
  82         int             sr_error;
  83 };
  84
  85 struct ptrace_vm_entry32 {
  86         int             pve_entry;
  87         int             pve_timestamp;
  88         uint32_t        pve_start;
  89         uint32_t        pve_end;
  90         uint32_t        pve_offset;
  91         u_int           pve_prot;
  92         u_int           pve_pathlen;
  93         int32_t         pve_fileid;
  94         u_int           pve_fsid;
  95         uint32_t        pve_path;
  96 };
  97 #endif
  98
  99 /*
 100  * Functions implemented using PROC_ACTION():
 101  *
 102  * proc_read_regs(proc, regs)
 103  *      Get the current user-visible register set from the process
 104  *      and copy it into the regs structure (<machine/reg.h>).
 105  *      The process is stopped at the time read_regs is called.
 106  *
 107  * proc_write_regs(proc, regs)
 108  *      Update the current register set from the passed in regs
 109  *      structure.  Take care to avoid clobbering special CPU
 110  *      registers or privileged bits in the PSL.
 111  *      Depending on the architecture this may have fix-up work to do,
 112  *      especially if the IAR or PCW are modified.
 113  *      The process is stopped at the time write_regs is called.
 114  *
 115  * proc_read_fpregs, proc_write_fpregs
 116  *      deal with the floating point register set, otherwise as above.
 117  *
 118  * proc_read_dbregs, proc_write_dbregs
 119  *      deal with the processor debug register set, otherwise as above.
 120  *
 121  * proc_sstep(proc)
 122  *      Arrange for the process to trap after executing a single instruction.
 123  */
 124
 125 #define PROC_ACTION(action) do {                                        \
 126         int error;                                                      \
 127                                                                         \
 128         PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);                        \
 129         if ((td->td_proc->p_flag & P_INMEM) == 0)                       \
 130                 error = EIO;                                            \
 131         else                                                            \
 132                 error = (action);                                       \
 133         return (error);                                                 \
 134 } while(0)
 135
 136 int
 137 proc_read_regs(struct thread *td, struct reg *regs)
 138 {
 139
 140         PROC_ACTION(fill_regs(td, regs));
 141 }
 142
 143 int
 144 proc_write_regs(struct thread *td, struct reg *regs)
 145 {
 146
 147         PROC_ACTION(set_regs(td, regs));
 148 }
 149
 150 int
 151 proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
 152 {
 153
 154         PROC_ACTION(fill_dbregs(td, dbregs));
 155 }
 156
 157 int
 158 proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
 159 {
 160
 161         PROC_ACTION(set_dbregs(td, dbregs));
 162 }
 163
 164 /*
 165  * Ptrace doesn't support fpregs at all, and there are no security holes
 166  * or translations for fpregs, so we can just copy them.
 167  */
 168 int
 169 proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
 170 {
 171
 172         PROC_ACTION(fill_fpregs(td, fpregs));
 173 }
 174
 175 int
 176 proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
 177 {
 178
 179         PROC_ACTION(set_fpregs(td, fpregs));
 180 }
 181
 182 #ifdef COMPAT_FREEBSD32
 183 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
 184 int
 185 proc_read_regs32(struct thread *td, struct reg32 *regs32)
 186 {
 187
 188         PROC_ACTION(fill_regs32(td, regs32));
 189 }
 190
 191 int
 192 proc_write_regs32(struct thread *td, struct reg32 *regs32)
 193 {
 194
 195         PROC_ACTION(set_regs32(td, regs32));
 196 }
 197
 198 int
 199 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 200 {
 201
 202         PROC_ACTION(fill_dbregs32(td, dbregs32));
 203 }
 204
 205 int
 206 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 207 {
 208
 209         PROC_ACTION(set_dbregs32(td, dbregs32));
 210 }
 211
 212 int
 213 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 214 {
 215
 216         PROC_ACTION(fill_fpregs32(td, fpregs32));
 217 }
 218
 219 int
 220 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 221 {
 222
 223         PROC_ACTION(set_fpregs32(td, fpregs32));
 224 }
 225 #endif
 226
 227 int
 228 proc_sstep(struct thread *td)
 229 {
 230
 231         PROC_ACTION(ptrace_single_step(td));
 232 }
 233
 234 int
 235 proc_rwmem(struct proc *p, struct uio *uio)
 236 {
 237         vm_map_t map;
 238         vm_offset_t pageno;             /* page number */
 239         vm_prot_t reqprot;
 240         int error, fault_flags, page_offset, writing;
 241
 242         /*
 243          * Assert that someone has locked this vmspace.  (Should be
 244          * curthread but we can't assert that.)  This keeps the process
 245          * from exiting out from under us until this operation completes.
 246          */
 247         PROC_ASSERT_HELD(p);
 248         PROC_LOCK_ASSERT(p, MA_NOTOWNED);
 249
 250         /*
 251          * The map we want...
 252          */
 253         map = &p->p_vmspace->vm_map;
 254
 255         /*
 256          * If we are writing, then we request vm_fault() to create a private
 257          * copy of each page.  Since these copies will not be writeable by the
 258          * process, we must explicity request that they be dirtied.
 259          */
 260         writing = uio->uio_rw == UIO_WRITE;
 261         reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
 262         fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL;
 263
 264         /*
 265          * Only map in one page at a time.  We don't have to, but it
 266          * makes things easier.  This way is trivial - right?
 267          */
 268         do {
 269                 vm_offset_t uva;
 270                 u_int len;
 271                 vm_page_t m;
 272
 273                 uva = (vm_offset_t)uio->uio_offset;
 274
 275                 /*
 276                  * Get the page number of this segment.
 277                  */
 278                 pageno = trunc_page(uva);
 279                 page_offset = uva - pageno;
 280
 281                 /*
 282                  * How many bytes to copy
 283                  */
 284                 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
 285
 286                 /*
 287                  * Fault and hold the page on behalf of the process.
 288                  */
 289                 error = vm_fault_hold(map, pageno, reqprot, fault_flags, &m);
 290                 if (error != KERN_SUCCESS) {
 291                         if (error == KERN_RESOURCE_SHORTAGE)
 292                                 error = ENOMEM;
 293                         else
 294                                 error = EFAULT;
 295                         break;
 296                 }
 297
 298                 /*
 299                  * Now do the i/o move.
 300                  */
 301                 error = uiomove_fromphys(&m, page_offset, len, uio);
 302
 303                 /* Make the I-cache coherent for breakpoints. */
 304                 if (writing && error == 0) {
 305                         vm_map_lock_read(map);
 306                         if (vm_map_check_protection(map, pageno, pageno +
 307                             PAGE_SIZE, VM_PROT_EXECUTE))
 308                                 vm_sync_icache(map, uva, len);
 309                         vm_map_unlock_read(map);
 310                 }
 311
 312                 /*
 313                  * Release the page.
 314                  */
 315                 vm_page_lock(m);
 316                 if (vm_page_unwire(m, PQ_ACTIVE) && m->object == NULL)
 317                         vm_page_free(m);
 318                 vm_page_unlock(m);
 319
 320         } while (error == 0 && uio->uio_resid > 0);
 321
 322         return (error);
 323 }
 324
 325 static ssize_t
 326 proc_iop(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 327     size_t len, enum uio_rw rw)
 328 {
 329         struct iovec iov;
 330         struct uio uio;
 331         ssize_t slen;
 332
 333         MPASS(len < SSIZE_MAX);
 334         slen = (ssize_t)len;
 335
 336         iov.iov_base = (caddr_t)buf;
 337         iov.iov_len = len;
 338         uio.uio_iov = &iov;
 339         uio.uio_iovcnt = 1;
 340         uio.uio_offset = va;
 341         uio.uio_resid = slen;
 342         uio.uio_segflg = UIO_SYSSPACE;
 343         uio.uio_rw = rw;
 344         uio.uio_td = td;
 345         proc_rwmem(p, &uio);
 346         if (uio.uio_resid == slen)
 347                 return (-1);
 348         return (slen - uio.uio_resid);
 349 }
 350
 351 ssize_t
 352 proc_readmem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 353     size_t len)
 354 {
 355
 356         return (proc_iop(td, p, va, buf, len, UIO_READ));
 357 }
 358
 359 ssize_t
 360 proc_writemem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 361     size_t len)
 362 {
 363
 364         return (proc_iop(td, p, va, buf, len, UIO_WRITE));
 365 }
 366
 367 static int
 368 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
 369 {
 370         struct vattr vattr;
 371         vm_map_t map;
 372         vm_map_entry_t entry;
 373         vm_object_t obj, tobj, lobj;
 374         struct vmspace *vm;
 375         struct vnode *vp;
 376         char *freepath, *fullpath;
 377         u_int pathlen;
 378         int error, index;
 379
 380         error = 0;
 381         obj = NULL;
 382
 383         vm = vmspace_acquire_ref(p);
 384         map = &vm->vm_map;
 385         vm_map_lock_read(map);
 386
 387         do {
 388                 entry = map->header.next;
 389                 index = 0;
 390                 while (index < pve->pve_entry && entry != &map->header) {
 391                         entry = entry->next;
 392                         index++;
 393                 }
 394                 if (index != pve->pve_entry) {
 395                         error = EINVAL;
 396                         break;
 397                 }
 398                 KASSERT((map->header.eflags & MAP_ENTRY_IS_SUB_MAP) == 0,
 399                     ("Submap in map header"));
 400                 while ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) {
 401                         entry = entry->next;
 402                         index++;
 403                 }
 404                 if (entry == &map->header) {
 405                         error = ENOENT;
 406                         break;
 407                 }
 408
 409                 /* We got an entry. */
 410                 pve->pve_entry = index + 1;
 411                 pve->pve_timestamp = map->timestamp;
 412                 pve->pve_start = entry->start;
 413                 pve->pve_end = entry->end - 1;
 414                 pve->pve_offset = entry->offset;
 415                 pve->pve_prot = entry->protection;
 416
 417                 /* Backing object's path needed? */
 418                 if (pve->pve_pathlen == 0)
 419                         break;
 420
 421                 pathlen = pve->pve_pathlen;
 422                 pve->pve_pathlen = 0;
 423
 424                 obj = entry->object.vm_object;
 425                 if (obj != NULL)
 426                         VM_OBJECT_RLOCK(obj);
 427         } while (0);
 428
 429         vm_map_unlock_read(map);
 430
 431         pve->pve_fsid = VNOVAL;
 432         pve->pve_fileid = VNOVAL;
 433
 434         if (error == 0 && obj != NULL) {
 435                 lobj = obj;
 436                 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
 437                         if (tobj != obj)
 438                                 VM_OBJECT_RLOCK(tobj);
 439                         if (lobj != obj)
 440                                 VM_OBJECT_RUNLOCK(lobj);
 441                         lobj = tobj;
 442                         pve->pve_offset += tobj->backing_object_offset;
 443                 }
 444                 vp = vm_object_vnode(lobj);
 445                 if (vp != NULL)
 446                         vref(vp);
 447                 if (lobj != obj)
 448                         VM_OBJECT_RUNLOCK(lobj);
 449                 VM_OBJECT_RUNLOCK(obj);
 450
 451                 if (vp != NULL) {
 452                         freepath = NULL;
 453                         fullpath = NULL;
 454                         vn_fullpath(td, vp, &fullpath, &freepath);
 455                         vn_lock(vp, LK_SHARED | LK_RETRY);
 456                         if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
 457                                 pve->pve_fileid = vattr.va_fileid;
 458                                 pve->pve_fsid = vattr.va_fsid;
 459                         }
 460                         vput(vp);
 461
 462                         if (fullpath != NULL) {
 463                                 pve->pve_pathlen = strlen(fullpath) + 1;
 464                                 if (pve->pve_pathlen <= pathlen) {
 465                                         error = copyout(fullpath, pve->pve_path,
 466                                             pve->pve_pathlen);
 467                                 } else
 468                                         error = ENAMETOOLONG;
 469                         }
 470                         if (freepath != NULL)
 471                                 free(freepath, M_TEMP);
 472                 }
 473         }
 474         vmspace_free(vm);
 475         if (error == 0)
 476                 CTR3(KTR_PTRACE, "PT_VM_ENTRY: pid %d, entry %d, start %p",
 477                     p->p_pid, pve->pve_entry, pve->pve_start);
 478
 479         return (error);
 480 }
 481
 482 #ifdef COMPAT_FREEBSD32
 483 static int
 484 ptrace_vm_entry32(struct thread *td, struct proc *p,
 485     struct ptrace_vm_entry32 *pve32)
 486 {
 487         struct ptrace_vm_entry pve;
 488         int error;
 489
 490         pve.pve_entry = pve32->pve_entry;
 491         pve.pve_pathlen = pve32->pve_pathlen;
 492         pve.pve_path = (void *)(uintptr_t)pve32->pve_path;
 493
 494         error = ptrace_vm_entry(td, p, &pve);
 495         if (error == 0) {
 496                 pve32->pve_entry = pve.pve_entry;
 497                 pve32->pve_timestamp = pve.pve_timestamp;
 498                 pve32->pve_start = pve.pve_start;
 499                 pve32->pve_end = pve.pve_end;
 500                 pve32->pve_offset = pve.pve_offset;
 501                 pve32->pve_prot = pve.pve_prot;
 502                 pve32->pve_fileid = pve.pve_fileid;
 503                 pve32->pve_fsid = pve.pve_fsid;
 504         }
 505
 506         pve32->pve_pathlen = pve.pve_pathlen;
 507         return (error);
 508 }
 509
 510 static void
 511 ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl,
 512     struct ptrace_lwpinfo32 *pl32)
 513 {
 514
 515         bzero(pl32, sizeof(*pl32));
 516         pl32->pl_lwpid = pl->pl_lwpid;
 517         pl32->pl_event = pl->pl_event;
 518         pl32->pl_flags = pl->pl_flags;
 519         pl32->pl_sigmask = pl->pl_sigmask;
 520         pl32->pl_siglist = pl->pl_siglist;
 521         siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo);
 522         strcpy(pl32->pl_tdname, pl->pl_tdname);
 523         pl32->pl_child_pid = pl->pl_child_pid;
 524         pl32->pl_syscall_code = pl->pl_syscall_code;
 525         pl32->pl_syscall_narg = pl->pl_syscall_narg;
 526 }
 527
 528 static void
 529 ptrace_sc_ret_to32(const struct ptrace_sc_ret *psr,
 530     struct ptrace_sc_ret32 *psr32)
 531 {
 532
 533         bzero(psr32, sizeof(*psr32));
 534         psr32->sr_retval[0] = psr->sr_retval[0];
 535         psr32->sr_retval[1] = psr->sr_retval[1];
 536         psr32->sr_error = psr->sr_error;
 537 }
 538 #endif /* COMPAT_FREEBSD32 */
 539
 540 /*
 541  * Process debugging system call.
 542  */
 543 #ifndef _SYS_SYSPROTO_H_
 544 struct ptrace_args {
 545         int     req;
 546         pid_t   pid;
 547         caddr_t addr;
 548         int     data;
 549 };
 550 #endif
 551
 552 #ifdef COMPAT_FREEBSD32
 553 /*
 554  * This CPP subterfuge is to try and reduce the number of ifdefs in
 555  * the body of the code.
 556  *   COPYIN(uap->addr, &r.reg, sizeof r.reg);
 557  * becomes either:
 558  *   copyin(uap->addr, &r.reg, sizeof r.reg);
 559  * or
 560  *   copyin(uap->addr, &r.reg32, sizeof r.reg32);
 561  * .. except this is done at runtime.
 562  */
 563 #define BZERO(a, s)             wrap32 ? \
 564         bzero(a ## 32, s ## 32) : \
 565         bzero(a, s)
 566 #define COPYIN(u, k, s)         wrap32 ? \
 567         copyin(u, k ## 32, s ## 32) : \
 568         copyin(u, k, s)
 569 #define COPYOUT(k, u, s)        wrap32 ? \
 570         copyout(k ## 32, u, s ## 32) : \
 571         copyout(k, u, s)
 572 #else
 573 #define BZERO(a, s)             bzero(a, s)
 574 #define COPYIN(u, k, s)         copyin(u, k, s)
 575 #define COPYOUT(k, u, s)        copyout(k, u, s)
 576 #endif
 577 int
 578 sys_ptrace(struct thread *td, struct ptrace_args *uap)
 579 {
 580         /*
 581          * XXX this obfuscation is to reduce stack usage, but the register
 582          * structs may be too large to put on the stack anyway.
 583          */
 584         union {
 585                 struct ptrace_io_desc piod;
 586                 struct ptrace_lwpinfo pl;
 587                 struct ptrace_vm_entry pve;
 588                 struct dbreg dbreg;
 589                 struct fpreg fpreg;
 590                 struct reg reg;
 591 #ifdef COMPAT_FREEBSD32
 592                 struct dbreg32 dbreg32;
 593                 struct fpreg32 fpreg32;
 594                 struct reg32 reg32;
 595                 struct ptrace_io_desc32 piod32;
 596                 struct ptrace_lwpinfo32 pl32;
 597                 struct ptrace_vm_entry32 pve32;
 598 #endif
 599                 char args[sizeof(td->td_sa.args)];
 600                 struct ptrace_sc_ret psr;
 601                 int ptevents;
 602         } r;
 603         void *addr;
 604         int error = 0;
 605 #ifdef COMPAT_FREEBSD32
 606         int wrap32 = 0;
 607
 608         if (SV_CURPROC_FLAG(SV_ILP32))
 609                 wrap32 = 1;
 610 #endif
 611         AUDIT_ARG_PID(uap->pid);
 612         AUDIT_ARG_CMD(uap->req);
 613         AUDIT_ARG_VALUE(uap->data);
 614         addr = &r;
 615         switch (uap->req) {
 616         case PT_GET_EVENT_MASK:
 617         case PT_LWPINFO:
 618         case PT_GET_SC_ARGS:
 619         case PT_GET_SC_RET:
 620                 break;
 621         case PT_GETREGS:
 622                 BZERO(&r.reg, sizeof r.reg);
 623                 break;
 624         case PT_GETFPREGS:
 625                 BZERO(&r.fpreg, sizeof r.fpreg);
 626                 break;
 627         case PT_GETDBREGS:
 628                 BZERO(&r.dbreg, sizeof r.dbreg);
 629                 break;
 630         case PT_SETREGS:
 631                 error = COPYIN(uap->addr, &r.reg, sizeof r.reg);
 632                 break;
 633         case PT_SETFPREGS:
 634                 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg);
 635                 break;
 636         case PT_SETDBREGS:
 637                 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg);
 638                 break;
 639         case PT_SET_EVENT_MASK:
 640                 if (uap->data != sizeof(r.ptevents))
 641                         error = EINVAL;
 642                 else
 643                         error = copyin(uap->addr, &r.ptevents, uap->data);
 644                 break;
 645         case PT_IO:
 646                 error = COPYIN(uap->addr, &r.piod, sizeof r.piod);
 647                 break;
 648         case PT_VM_ENTRY:
 649                 error = COPYIN(uap->addr, &r.pve, sizeof r.pve);
 650                 break;
 651         default:
 652                 addr = uap->addr;
 653                 break;
 654         }
 655         if (error)
 656                 return (error);
 657
 658         error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
 659         if (error)
 660                 return (error);
 661
 662         switch (uap->req) {
 663         case PT_VM_ENTRY:
 664                 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve);
 665                 break;
 666         case PT_IO:
 667                 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod);
 668                 break;
 669         case PT_GETREGS:
 670                 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg);
 671                 break;
 672         case PT_GETFPREGS:
 673                 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg);
 674                 break;
 675         case PT_GETDBREGS:
 676                 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg);
 677                 break;
 678         case PT_GET_EVENT_MASK:
 679                 /* NB: The size in uap->data is validated in kern_ptrace(). */
 680                 error = copyout(&r.ptevents, uap->addr, uap->data);
 681                 break;
 682         case PT_LWPINFO:
 683                 /* NB: The size in uap->data is validated in kern_ptrace(). */
 684                 error = copyout(&r.pl, uap->addr, uap->data);
 685                 break;
 686         case PT_GET_SC_ARGS:
 687                 error = copyout(r.args, uap->addr, MIN(uap->data,
 688                     sizeof(r.args)));
 689                 break;
 690         case PT_GET_SC_RET:
 691                 error = copyout(&r.psr, uap->addr, MIN(uap->data,
 692                     sizeof(r.psr)));
 693                 break;
 694         }
 695
 696         return (error);
 697 }
 698 #undef COPYIN
 699 #undef COPYOUT
 700 #undef BZERO
 701
 702 #ifdef COMPAT_FREEBSD32
 703 /*
 704  *   PROC_READ(regs, td2, addr);
 705  * becomes either:
 706  *   proc_read_regs(td2, addr);
 707  * or
 708  *   proc_read_regs32(td2, addr);
 709  * .. except this is done at runtime.  There is an additional
 710  * complication in that PROC_WRITE disallows 32 bit consumers
 711  * from writing to 64 bit address space targets.
 712  */
 713 #define PROC_READ(w, t, a)      wrap32 ? \
 714         proc_read_ ## w ## 32(t, a) : \
 715         proc_read_ ## w (t, a)
 716 #define PROC_WRITE(w, t, a)     wrap32 ? \
 717         (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
 718         proc_write_ ## w (t, a)
 719 #else
 720 #define PROC_READ(w, t, a)      proc_read_ ## w (t, a)
 721 #define PROC_WRITE(w, t, a)     proc_write_ ## w (t, a)
 722 #endif
 723
 724 void
 725 proc_set_traced(struct proc *p, bool stop)
 726 {
 727
 728         sx_assert(&proctree_lock, SX_XLOCKED);
 729         PROC_LOCK_ASSERT(p, MA_OWNED);
 730         p->p_flag |= P_TRACED;
 731         if (stop)
 732                 p->p_flag2 |= P2_PTRACE_FSTP;
 733         p->p_ptevents = PTRACE_DEFAULT;
 734 }
 735
 736 int
 737 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 738 {
 739         struct iovec iov;
 740         struct uio uio;
 741         struct proc *curp, *p, *pp;
 742         struct thread *td2 = NULL, *td3;
 743         struct ptrace_io_desc *piod = NULL;
 744         struct ptrace_lwpinfo *pl;
 745         struct ptrace_sc_ret *psr;
 746         int error, num, tmp;
 747         int proctree_locked = 0;
 748         lwpid_t tid = 0, *buf;
 749 #ifdef COMPAT_FREEBSD32
 750         int wrap32 = 0, safe = 0;
 751         struct ptrace_io_desc32 *piod32 = NULL;
 752         struct ptrace_lwpinfo32 *pl32 = NULL;
 753         struct ptrace_sc_ret32 *psr32 = NULL;
 754         union {
 755                 struct ptrace_lwpinfo pl;
 756                 struct ptrace_sc_ret psr;
 757         } r;
 758 #endif
 759
 760         curp = td->td_proc;
 761
 762         /* Lock proctree before locking the process. */
 763         switch (req) {
 764         case PT_TRACE_ME:
 765         case PT_ATTACH:
 766         case PT_STEP:
 767         case PT_CONTINUE:
 768         case PT_TO_SCE:
 769         case PT_TO_SCX:
 770         case PT_SYSCALL:
 771         case PT_FOLLOW_FORK:
 772         case PT_LWP_EVENTS:
 773         case PT_GET_EVENT_MASK:
 774         case PT_SET_EVENT_MASK:
 775         case PT_DETACH:
 776         case PT_GET_SC_ARGS:
 777                 sx_xlock(&proctree_lock);
 778                 proctree_locked = 1;
 779                 break;
 780         default:
 781                 break;
 782         }
 783
 784         if (req == PT_TRACE_ME) {
 785                 p = td->td_proc;
 786                 PROC_LOCK(p);
 787         } else {
 788                 if (pid <= PID_MAX) {
 789                         if ((p = pfind(pid)) == NULL) {
 790                                 if (proctree_locked)
 791                                         sx_xunlock(&proctree_lock);
 792                                 return (ESRCH);
 793                         }
 794                 } else {
 795                         td2 = tdfind(pid, -1);
 796                         if (td2 == NULL) {
 797                                 if (proctree_locked)
 798                                         sx_xunlock(&proctree_lock);
 799                                 return (ESRCH);
 800                         }
 801                         p = td2->td_proc;
 802                         tid = pid;
 803                         pid = p->p_pid;
 804                 }
 805         }
 806         AUDIT_ARG_PROCESS(p);
 807
 808         if ((p->p_flag & P_WEXIT) != 0) {
 809                 error = ESRCH;
 810                 goto fail;
 811         }
 812         if ((error = p_cansee(td, p)) != 0)
 813                 goto fail;
 814
 815         if ((error = p_candebug(td, p)) != 0)
 816                 goto fail;
 817
 818         /*
 819          * System processes can't be debugged.
 820          */
 821         if ((p->p_flag & P_SYSTEM) != 0) {
 822                 error = EINVAL;
 823                 goto fail;
 824         }
 825
 826         if (tid == 0) {
 827                 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
 828                         KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
 829                         td2 = p->p_xthread;
 830                 } else {
 831                         td2 = FIRST_THREAD_IN_PROC(p);
 832                 }
 833                 tid = td2->td_tid;
 834         }
 835
 836 #ifdef COMPAT_FREEBSD32
 837         /*
 838          * Test if we're a 32 bit client and what the target is.
 839          * Set the wrap controls accordingly.
 840          */
 841         if (SV_CURPROC_FLAG(SV_ILP32)) {
 842                 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32))
 843                         safe = 1;
 844                 wrap32 = 1;
 845         }
 846 #endif
 847         /*
 848          * Permissions check
 849          */
 850         switch (req) {
 851         case PT_TRACE_ME:
 852                 /*
 853                  * Always legal, when there is a parent process which
 854                  * could trace us.  Otherwise, reject.
 855                  */
 856                 if ((p->p_flag & P_TRACED) != 0) {
 857                         error = EBUSY;
 858                         goto fail;
 859                 }
 860                 if (p->p_pptr == initproc) {
 861                         error = EPERM;
 862                         goto fail;
 863                 }
 864                 break;
 865
 866         case PT_ATTACH:
 867                 /* Self */
 868                 if (p == td->td_proc) {
 869                         error = EINVAL;
 870                         goto fail;
 871                 }
 872
 873                 /* Already traced */
 874                 if (p->p_flag & P_TRACED) {
 875                         error = EBUSY;
 876                         goto fail;
 877                 }
 878
 879                 /* Can't trace an ancestor if you're being traced. */
 880                 if (curp->p_flag & P_TRACED) {
 881                         for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
 882                                 if (pp == p) {
 883                                         error = EINVAL;
 884                                         goto fail;
 885                                 }
 886                         }
 887                 }
 888
 889
 890                 /* OK */
 891                 break;
 892
 893         case PT_CLEARSTEP:
 894                 /* Allow thread to clear single step for itself */
 895                 if (td->td_tid == tid)
 896                         break;
 897
 898                 /* FALLTHROUGH */
 899         default:
 900                 /* not being traced... */
 901                 if ((p->p_flag & P_TRACED) == 0) {
 902                         error = EPERM;
 903                         goto fail;
 904                 }
 905
 906                 /* not being traced by YOU */
 907                 if (p->p_pptr != td->td_proc) {
 908                         error = EBUSY;
 909                         goto fail;
 910                 }
 911
 912                 /* not currently stopped */
 913                 if ((p->p_flag & P_STOPPED_TRACE) == 0 ||
 914                     p->p_suspcount != p->p_numthreads  ||
 915                     (p->p_flag & P_WAITED) == 0) {
 916                         error = EBUSY;
 917                         goto fail;
 918                 }
 919
 920                 /* OK */
 921                 break;
 922         }
 923
 924         /* Keep this process around until we finish this request. */
 925         _PHOLD(p);
 926
 927 #ifdef FIX_SSTEP
 928         /*
 929          * Single step fixup ala procfs
 930          */
 931         FIX_SSTEP(td2);
 932 #endif
 933
 934         /*
 935          * Actually do the requests
 936          */
 937
 938         td->td_retval[0] = 0;
 939
 940         switch (req) {
 941         case PT_TRACE_ME:
 942                 /* set my trace flag and "owner" so it can read/write me */
 943                 proc_set_traced(p, false);
 944                 if (p->p_flag & P_PPWAIT)
 945                         p->p_flag |= P_PPTRACE;
 946                 CTR1(KTR_PTRACE, "PT_TRACE_ME: pid %d", p->p_pid);
 947                 break;
 948
 949         case PT_ATTACH:
 950                 /* security check done above */
 951                 /*
 952                  * It would be nice if the tracing relationship was separate
 953                  * from the parent relationship but that would require
 954                  * another set of links in the proc struct or for "wait"
 955                  * to scan the entire proc table.  To make life easier,
 956                  * we just re-parent the process we're trying to trace.
 957                  * The old parent is remembered so we can put things back
 958                  * on a "detach".
 959                  */
 960                 proc_set_traced(p, true);
 961                 proc_reparent(p, td->td_proc, false);
 962                 CTR2(KTR_PTRACE, "PT_ATTACH: pid %d, oppid %d", p->p_pid,
 963                     p->p_oppid);
 964
 965                 sx_xunlock(&proctree_lock);
 966                 proctree_locked = 0;
 967                 MPASS(p->p_xthread == NULL);
 968                 MPASS((p->p_flag & P_STOPPED_TRACE) == 0);
 969
 970                 /*
 971                  * If already stopped due to a stop signal, clear the
 972                  * existing stop before triggering a traced SIGSTOP.
 973                  */
 974                 if ((p->p_flag & P_STOPPED_SIG) != 0) {
 975                         PROC_SLOCK(p);
 976                         p->p_flag &= ~(P_STOPPED_SIG | P_WAITED);
 977                         thread_unsuspend(p);
 978                         PROC_SUNLOCK(p);
 979                 }
 980
 981                 kern_psignal(p, SIGSTOP);
 982                 break;
 983
 984         case PT_CLEARSTEP:
 985                 CTR2(KTR_PTRACE, "PT_CLEARSTEP: tid %d (pid %d)", td2->td_tid,
 986                     p->p_pid);
 987                 error = ptrace_clear_single_step(td2);
 988                 break;
 989
 990         case PT_SETSTEP:
 991                 CTR2(KTR_PTRACE, "PT_SETSTEP: tid %d (pid %d)", td2->td_tid,
 992                     p->p_pid);
 993                 error = ptrace_single_step(td2);
 994                 break;
 995
 996         case PT_SUSPEND:
 997                 CTR2(KTR_PTRACE, "PT_SUSPEND: tid %d (pid %d)", td2->td_tid,
 998                     p->p_pid);
 999                 td2->td_dbgflags |= TDB_SUSPEND;
1000                 thread_lock(td2);
1001                 td2->td_flags |= TDF_NEEDSUSPCHK;
1002                 thread_unlock(td2);
1003                 break;
1004
1005         case PT_RESUME:
1006                 CTR2(KTR_PTRACE, "PT_RESUME: tid %d (pid %d)", td2->td_tid,
1007                     p->p_pid);
1008                 td2->td_dbgflags &= ~TDB_SUSPEND;
1009                 break;
1010
1011         case PT_FOLLOW_FORK:
1012                 CTR3(KTR_PTRACE, "PT_FOLLOW_FORK: pid %d %s -> %s", p->p_pid,
1013                     p->p_ptevents & PTRACE_FORK ? "enabled" : "disabled",
1014                     data ? "enabled" : "disabled");
1015                 if (data)
1016                         p->p_ptevents |= PTRACE_FORK;
1017                 else
1018                         p->p_ptevents &= ~PTRACE_FORK;
1019                 break;
1020
1021         case PT_LWP_EVENTS:
1022                 CTR3(KTR_PTRACE, "PT_LWP_EVENTS: pid %d %s -> %s", p->p_pid,
1023                     p->p_ptevents & PTRACE_LWP ? "enabled" : "disabled",
1024                     data ? "enabled" : "disabled");
1025                 if (data)
1026                         p->p_ptevents |= PTRACE_LWP;
1027                 else
1028                         p->p_ptevents &= ~PTRACE_LWP;
1029                 break;
1030
1031         case PT_GET_EVENT_MASK:
1032                 if (data != sizeof(p->p_ptevents)) {
1033                         error = EINVAL;
1034                         break;
1035                 }
1036                 CTR2(KTR_PTRACE, "PT_GET_EVENT_MASK: pid %d mask %#x", p->p_pid,
1037                     p->p_ptevents);
1038                 *(int *)addr = p->p_ptevents;
1039                 break;
1040
1041         case PT_SET_EVENT_MASK:
1042                 if (data != sizeof(p->p_ptevents)) {
1043                         error = EINVAL;
1044                         break;
1045                 }
1046                 tmp = *(int *)addr;
1047                 if ((tmp & ~(PTRACE_EXEC | PTRACE_SCE | PTRACE_SCX |
1048                     PTRACE_FORK | PTRACE_LWP | PTRACE_VFORK)) != 0) {
1049                         error = EINVAL;
1050                         break;
1051                 }
1052                 CTR3(KTR_PTRACE, "PT_SET_EVENT_MASK: pid %d mask %#x -> %#x",
1053                     p->p_pid, p->p_ptevents, tmp);
1054                 p->p_ptevents = tmp;
1055                 break;
1056
1057         case PT_GET_SC_ARGS:
1058                 CTR1(KTR_PTRACE, "PT_GET_SC_ARGS: pid %d", p->p_pid);
1059                 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) == 0
1060 #ifdef COMPAT_FREEBSD32
1061                     || (wrap32 && !safe)
1062 #endif
1063                     ) {
1064                         error = EINVAL;
1065                         break;
1066                 }
1067                 bzero(addr, sizeof(td2->td_sa.args));
1068 #ifdef COMPAT_FREEBSD32
1069                 if (wrap32)
1070                         for (num = 0; num < nitems(td2->td_sa.args); num++)
1071                                 ((uint32_t *)addr)[num] = (uint32_t)
1072                                     td2->td_sa.args[num];
1073                 else
1074 #endif
1075                         bcopy(td2->td_sa.args, addr, td2->td_sa.narg *
1076                             sizeof(register_t));
1077                 break;
1078
1079         case PT_GET_SC_RET:
1080                 if ((td2->td_dbgflags & (TDB_SCX)) == 0
1081 #ifdef COMPAT_FREEBSD32
1082                     || (wrap32 && !safe)
1083 #endif
1084                     ) {
1085                         error = EINVAL;
1086                         break;
1087                 }
1088 #ifdef COMPAT_FREEBSD32
1089                 if (wrap32) {
1090                         psr = &r.psr;
1091                         psr32 = addr;
1092                 } else
1093 #endif
1094                 psr = addr;
1095                 bzero(psr, sizeof(*psr));
1096                 psr->sr_error = td2->td_errno;
1097                 if (psr->sr_error == 0) {
1098                         psr->sr_retval[0] = td2->td_retval[0];
1099                         psr->sr_retval[1] = td2->td_retval[1];
1100                 }
1101 #ifdef COMPAT_FREEBSD32
1102                 if (wrap32)
1103                         ptrace_sc_ret_to32(psr, psr32);
1104 #endif
1105                 CTR4(KTR_PTRACE,
1106                     "PT_GET_SC_RET: pid %d error %d retval %#lx,%#lx",
1107                     p->p_pid, psr->sr_error, psr->sr_retval[0],
1108                     psr->sr_retval[1]);
1109                 break;
1110
1111         case PT_STEP:
1112         case PT_CONTINUE:
1113         case PT_TO_SCE:
1114         case PT_TO_SCX:
1115         case PT_SYSCALL:
1116         case PT_DETACH:
1117                 /* Zero means do not send any signal */
1118                 if (data < 0 || data > _SIG_MAXSIG) {
1119                         error = EINVAL;
1120                         break;
1121                 }
1122
1123                 switch (req) {
1124                 case PT_STEP:
1125                         CTR3(KTR_PTRACE, "PT_STEP: tid %d (pid %d), sig = %d",
1126                             td2->td_tid, p->p_pid, data);
1127                         error = ptrace_single_step(td2);
1128                         if (error)
1129                                 goto out;
1130                         break;
1131                 case PT_CONTINUE:
1132                 case PT_TO_SCE:
1133                 case PT_TO_SCX:
1134                 case PT_SYSCALL:
1135                         if (addr != (void *)1) {
1136                                 error = ptrace_set_pc(td2,
1137                                     (u_long)(uintfptr_t)addr);
1138                                 if (error)
1139                                         goto out;
1140                         }
1141                         switch (req) {
1142                         case PT_TO_SCE:
1143                                 p->p_ptevents |= PTRACE_SCE;
1144                                 CTR4(KTR_PTRACE,
1145                     "PT_TO_SCE: pid %d, events = %#x, PC = %#lx, sig = %d",
1146                                     p->p_pid, p->p_ptevents,
1147                                     (u_long)(uintfptr_t)addr, data);
1148                                 break;
1149                         case PT_TO_SCX:
1150                                 p->p_ptevents |= PTRACE_SCX;
1151                                 CTR4(KTR_PTRACE,
1152                     "PT_TO_SCX: pid %d, events = %#x, PC = %#lx, sig = %d",
1153                                     p->p_pid, p->p_ptevents,
1154                                     (u_long)(uintfptr_t)addr, data);
1155                                 break;
1156                         case PT_SYSCALL:
1157                                 p->p_ptevents |= PTRACE_SYSCALL;
1158                                 CTR4(KTR_PTRACE,
1159                     "PT_SYSCALL: pid %d, events = %#x, PC = %#lx, sig = %d",
1160                                     p->p_pid, p->p_ptevents,
1161                                     (u_long)(uintfptr_t)addr, data);
1162                                 break;
1163                         case PT_CONTINUE:
1164                                 CTR3(KTR_PTRACE,
1165                                     "PT_CONTINUE: pid %d, PC = %#lx, sig = %d",
1166                                     p->p_pid, (u_long)(uintfptr_t)addr, data);
1167                                 break;
1168                         }
1169                         break;
1170                 case PT_DETACH:
1171                         /*
1172                          * Reset the process parent.
1173                          *
1174                          * NB: This clears P_TRACED before reparenting
1175                          * a detached process back to its original
1176                          * parent.  Otherwise the debugee will be set
1177                          * as an orphan of the debugger.
1178                          */
1179                         p->p_flag &= ~(P_TRACED | P_WAITED);
1180                         if (p->p_oppid != p->p_pptr->p_pid) {
1181                                 PROC_LOCK(p->p_pptr);
1182                                 sigqueue_take(p->p_ksi);
1183                                 PROC_UNLOCK(p->p_pptr);
1184
1185                                 pp = proc_realparent(p);
1186                                 proc_reparent(p, pp, false);
1187                                 if (pp == initproc)
1188                                         p->p_sigparent = SIGCHLD;
1189                                 CTR3(KTR_PTRACE,
1190                             "PT_DETACH: pid %d reparented to pid %d, sig %d",
1191                                     p->p_pid, pp->p_pid, data);
1192                         } else
1193                                 CTR2(KTR_PTRACE, "PT_DETACH: pid %d, sig %d",
1194                                     p->p_pid, data);
1195                         p->p_ptevents = 0;
1196                         FOREACH_THREAD_IN_PROC(p, td3) {
1197                                 if ((td3->td_dbgflags & TDB_FSTP) != 0) {
1198                                         sigqueue_delete(&td3->td_sigqueue,
1199                                             SIGSTOP);
1200                                 }
1201                                 td3->td_dbgflags &= ~(TDB_XSIG | TDB_FSTP |
1202                                     TDB_SUSPEND);
1203                         }
1204
1205                         if ((p->p_flag2 & P2_PTRACE_FSTP) != 0) {
1206                                 sigqueue_delete(&p->p_sigqueue, SIGSTOP);
1207                                 p->p_flag2 &= ~P2_PTRACE_FSTP;
1208                         }
1209
1210                         /* should we send SIGCHLD? */
1211                         /* childproc_continued(p); */
1212                         break;
1213                 }
1214
1215                 sx_xunlock(&proctree_lock);
1216                 proctree_locked = 0;
1217
1218         sendsig:
1219                 MPASS(proctree_locked == 0);
1220
1221                 /*
1222                  * Clear the pending event for the thread that just
1223                  * reported its event (p_xthread).  This may not be
1224                  * the thread passed to PT_CONTINUE, PT_STEP, etc. if
1225                  * the debugger is resuming a different thread.
1226                  *
1227                  * Deliver any pending signal via the reporting thread.
1228                  */
1229                 MPASS(p->p_xthread != NULL);
1230                 p->p_xthread->td_dbgflags &= ~TDB_XSIG;
1231                 p->p_xthread->td_xsig = data;
1232                 p->p_xthread = NULL;
1233                 p->p_xsig = data;
1234
1235                 /*
1236                  * P_WKILLED is insurance that a PT_KILL/SIGKILL
1237                  * always works immediately, even if another thread is
1238                  * unsuspended first and attempts to handle a
1239                  * different signal or if the POSIX.1b style signal
1240                  * queue cannot accommodate any new signals.
1241                  */
1242                 if (data == SIGKILL)
1243                         proc_wkilled(p);
1244
1245                 /*
1246                  * Unsuspend all threads.  To leave a thread
1247                  * suspended, use PT_SUSPEND to suspend it before
1248                  * continuing the process.
1249                  */
1250                 PROC_SLOCK(p);
1251                 p->p_flag &= ~(P_STOPPED_TRACE | P_STOPPED_SIG | P_WAITED);
1252                 thread_unsuspend(p);
1253                 PROC_SUNLOCK(p);
1254                 break;
1255
1256         case PT_WRITE_I:
1257         case PT_WRITE_D:
1258                 td2->td_dbgflags |= TDB_USERWR;
1259                 PROC_UNLOCK(p);
1260                 error = 0;
1261                 if (proc_writemem(td, p, (off_t)(uintptr_t)addr, &data,
1262                     sizeof(int)) != sizeof(int))
1263                         error = ENOMEM;
1264                 else
1265                         CTR3(KTR_PTRACE, "PT_WRITE: pid %d: %p <= %#x",
1266                             p->p_pid, addr, data);
1267                 PROC_LOCK(p);
1268                 break;
1269
1270         case PT_READ_I:
1271         case PT_READ_D:
1272                 PROC_UNLOCK(p);
1273                 error = tmp = 0;
1274                 if (proc_readmem(td, p, (off_t)(uintptr_t)addr, &tmp,
1275                     sizeof(int)) != sizeof(int))
1276                         error = ENOMEM;
1277                 else
1278                         CTR3(KTR_PTRACE, "PT_READ: pid %d: %p >= %#x",
1279                             p->p_pid, addr, tmp);
1280                 td->td_retval[0] = tmp;
1281                 PROC_LOCK(p);
1282                 break;
1283
1284         case PT_IO:
1285 #ifdef COMPAT_FREEBSD32
1286                 if (wrap32) {
1287                         piod32 = addr;
1288                         iov.iov_base = (void *)(uintptr_t)piod32->piod_addr;
1289                         iov.iov_len = piod32->piod_len;
1290                         uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs;
1291                         uio.uio_resid = piod32->piod_len;
1292                 } else
1293 #endif
1294                 {
1295                         piod = addr;
1296                         iov.iov_base = piod->piod_addr;
1297                         iov.iov_len = piod->piod_len;
1298                         uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
1299                         uio.uio_resid = piod->piod_len;
1300                 }
1301                 uio.uio_iov = &iov;
1302                 uio.uio_iovcnt = 1;
1303                 uio.uio_segflg = UIO_USERSPACE;
1304                 uio.uio_td = td;
1305 #ifdef COMPAT_FREEBSD32
1306                 tmp = wrap32 ? piod32->piod_op : piod->piod_op;
1307 #else
1308                 tmp = piod->piod_op;
1309 #endif
1310                 switch (tmp) {
1311                 case PIOD_READ_D:
1312                 case PIOD_READ_I:
1313                         CTR3(KTR_PTRACE, "PT_IO: pid %d: READ (%p, %#x)",
1314                             p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1315                         uio.uio_rw = UIO_READ;
1316                         break;
1317                 case PIOD_WRITE_D:
1318                 case PIOD_WRITE_I:
1319                         CTR3(KTR_PTRACE, "PT_IO: pid %d: WRITE (%p, %#x)",
1320                             p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1321                         td2->td_dbgflags |= TDB_USERWR;
1322                         uio.uio_rw = UIO_WRITE;
1323                         break;
1324                 default:
1325                         error = EINVAL;
1326                         goto out;
1327                 }
1328                 PROC_UNLOCK(p);
1329                 error = proc_rwmem(p, &uio);
1330 #ifdef COMPAT_FREEBSD32
1331                 if (wrap32)
1332                         piod32->piod_len -= uio.uio_resid;
1333                 else
1334 #endif
1335                         piod->piod_len -= uio.uio_resid;
1336                 PROC_LOCK(p);
1337                 break;
1338
1339         case PT_KILL:
1340                 CTR1(KTR_PTRACE, "PT_KILL: pid %d", p->p_pid);
1341                 data = SIGKILL;
1342                 goto sendsig;   /* in PT_CONTINUE above */
1343
1344         case PT_SETREGS:
1345                 CTR2(KTR_PTRACE, "PT_SETREGS: tid %d (pid %d)", td2->td_tid,
1346                     p->p_pid);
1347                 td2->td_dbgflags |= TDB_USERWR;
1348                 error = PROC_WRITE(regs, td2, addr);
1349                 break;
1350
1351         case PT_GETREGS:
1352                 CTR2(KTR_PTRACE, "PT_GETREGS: tid %d (pid %d)", td2->td_tid,
1353                     p->p_pid);
1354                 error = PROC_READ(regs, td2, addr);
1355                 break;
1356
1357         case PT_SETFPREGS:
1358                 CTR2(KTR_PTRACE, "PT_SETFPREGS: tid %d (pid %d)", td2->td_tid,
1359                     p->p_pid);
1360                 td2->td_dbgflags |= TDB_USERWR;
1361                 error = PROC_WRITE(fpregs, td2, addr);
1362                 break;
1363
1364         case PT_GETFPREGS:
1365                 CTR2(KTR_PTRACE, "PT_GETFPREGS: tid %d (pid %d)", td2->td_tid,
1366                     p->p_pid);
1367                 error = PROC_READ(fpregs, td2, addr);
1368                 break;
1369
1370         case PT_SETDBREGS:
1371                 CTR2(KTR_PTRACE, "PT_SETDBREGS: tid %d (pid %d)", td2->td_tid,
1372                     p->p_pid);
1373                 td2->td_dbgflags |= TDB_USERWR;
1374                 error = PROC_WRITE(dbregs, td2, addr);
1375                 break;
1376
1377         case PT_GETDBREGS:
1378                 CTR2(KTR_PTRACE, "PT_GETDBREGS: tid %d (pid %d)", td2->td_tid,
1379                     p->p_pid);
1380                 error = PROC_READ(dbregs, td2, addr);
1381                 break;
1382
1383         case PT_LWPINFO:
1384                 if (data <= 0 ||
1385 #ifdef COMPAT_FREEBSD32
1386                     (!wrap32 && data > sizeof(*pl)) ||
1387                     (wrap32 && data > sizeof(*pl32))) {
1388 #else
1389                     data > sizeof(*pl)) {
1390 #endif
1391                         error = EINVAL;
1392                         break;
1393                 }
1394 #ifdef COMPAT_FREEBSD32
1395                 if (wrap32) {
1396                         pl = &r.pl;
1397                         pl32 = addr;
1398                 } else
1399 #endif
1400                 pl = addr;
1401                 bzero(pl, sizeof(*pl));
1402                 pl->pl_lwpid = td2->td_tid;
1403                 pl->pl_event = PL_EVENT_NONE;
1404                 pl->pl_flags = 0;
1405                 if (td2->td_dbgflags & TDB_XSIG) {
1406                         pl->pl_event = PL_EVENT_SIGNAL;
1407                         if (td2->td_si.si_signo != 0 &&
1408 #ifdef COMPAT_FREEBSD32
1409                             ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo,
1410                             pl_siginfo) + sizeof(pl->pl_siginfo)) ||
1411                             (wrap32 && data >= offsetof(struct ptrace_lwpinfo32,
1412                             pl_siginfo) + sizeof(struct siginfo32)))
1413 #else
1414                             data >= offsetof(struct ptrace_lwpinfo, pl_siginfo)
1415                             + sizeof(pl->pl_siginfo)
1416 #endif
1417                         ){
1418                                 pl->pl_flags |= PL_FLAG_SI;
1419                                 pl->pl_siginfo = td2->td_si;
1420                         }
1421                 }
1422                 if (td2->td_dbgflags & TDB_SCE)
1423                         pl->pl_flags |= PL_FLAG_SCE;
1424                 else if (td2->td_dbgflags & TDB_SCX)
1425                         pl->pl_flags |= PL_FLAG_SCX;
1426                 if (td2->td_dbgflags & TDB_EXEC)
1427                         pl->pl_flags |= PL_FLAG_EXEC;
1428                 if (td2->td_dbgflags & TDB_FORK) {
1429                         pl->pl_flags |= PL_FLAG_FORKED;
1430                         pl->pl_child_pid = td2->td_dbg_forked;
1431                         if (td2->td_dbgflags & TDB_VFORK)
1432                                 pl->pl_flags |= PL_FLAG_VFORKED;
1433                 } else if ((td2->td_dbgflags & (TDB_SCX | TDB_VFORK)) ==
1434                     TDB_VFORK)
1435                         pl->pl_flags |= PL_FLAG_VFORK_DONE;
1436                 if (td2->td_dbgflags & TDB_CHILD)
1437                         pl->pl_flags |= PL_FLAG_CHILD;
1438                 if (td2->td_dbgflags & TDB_BORN)
1439                         pl->pl_flags |= PL_FLAG_BORN;
1440                 if (td2->td_dbgflags & TDB_EXIT)
1441                         pl->pl_flags |= PL_FLAG_EXITED;
1442                 pl->pl_sigmask = td2->td_sigmask;
1443                 pl->pl_siglist = td2->td_siglist;
1444                 strcpy(pl->pl_tdname, td2->td_name);
1445                 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) != 0) {
1446                         pl->pl_syscall_code = td2->td_sa.code;
1447                         pl->pl_syscall_narg = td2->td_sa.narg;
1448                 } else {
1449                         pl->pl_syscall_code = 0;
1450                         pl->pl_syscall_narg = 0;
1451                 }
1452 #ifdef COMPAT_FREEBSD32
1453                 if (wrap32)
1454                         ptrace_lwpinfo_to32(pl, pl32);
1455 #endif
1456                 CTR6(KTR_PTRACE,
1457     "PT_LWPINFO: tid %d (pid %d) event %d flags %#x child pid %d syscall %d",
1458                     td2->td_tid, p->p_pid, pl->pl_event, pl->pl_flags,
1459                     pl->pl_child_pid, pl->pl_syscall_code);
1460                 break;
1461
1462         case PT_GETNUMLWPS:
1463                 CTR2(KTR_PTRACE, "PT_GETNUMLWPS: pid %d: %d threads", p->p_pid,
1464                     p->p_numthreads);
1465                 td->td_retval[0] = p->p_numthreads;
1466                 break;
1467
1468         case PT_GETLWPLIST:
1469                 CTR3(KTR_PTRACE, "PT_GETLWPLIST: pid %d: data %d, actual %d",
1470                     p->p_pid, data, p->p_numthreads);
1471                 if (data <= 0) {
1472                         error = EINVAL;
1473                         break;
1474                 }
1475                 num = imin(p->p_numthreads, data);
1476                 PROC_UNLOCK(p);
1477                 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
1478                 tmp = 0;
1479                 PROC_LOCK(p);
1480                 FOREACH_THREAD_IN_PROC(p, td2) {
1481                         if (tmp >= num)
1482                                 break;
1483                         buf[tmp++] = td2->td_tid;
1484                 }
1485                 PROC_UNLOCK(p);
1486                 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
1487                 free(buf, M_TEMP);
1488                 if (!error)
1489                         td->td_retval[0] = tmp;
1490                 PROC_LOCK(p);
1491                 break;
1492
1493         case PT_VM_TIMESTAMP:
1494                 CTR2(KTR_PTRACE, "PT_VM_TIMESTAMP: pid %d: timestamp %d",
1495                     p->p_pid, p->p_vmspace->vm_map.timestamp);
1496                 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
1497                 break;
1498
1499         case PT_VM_ENTRY:
1500                 PROC_UNLOCK(p);
1501 #ifdef COMPAT_FREEBSD32
1502                 if (wrap32)
1503                         error = ptrace_vm_entry32(td, p, addr);
1504                 else
1505 #endif
1506                 error = ptrace_vm_entry(td, p, addr);
1507                 PROC_LOCK(p);
1508                 break;
1509
1510         default:
1511 #ifdef __HAVE_PTRACE_MACHDEP
1512                 if (req >= PT_FIRSTMACH) {
1513                         PROC_UNLOCK(p);
1514                         error = cpu_ptrace(td2, req, addr, data);
1515                         PROC_LOCK(p);
1516                 } else
1517 #endif
1518                         /* Unknown request. */
1519                         error = EINVAL;
1520                 break;
1521         }
1522
1523 out:
1524         /* Drop our hold on this process now that the request has completed. */
1525         _PRELE(p);
1526 fail:
1527         PROC_UNLOCK(p);
1528         if (proctree_locked)
1529                 sx_xunlock(&proctree_lock);
1530         return (error);
1531 }
1532 #undef PROC_READ
1533 #undef PROC_WRITE
1534
1535 /*
1536  * Stop a process because of a debugging event;
1537  * stay stopped until p->p_step is cleared
1538  * (cleared by PIOCCONT in procfs).
1539  */
1540 void
1541 stopevent(struct proc *p, unsigned int event, unsigned int val)
1542 {
1543
1544         PROC_LOCK_ASSERT(p, MA_OWNED);
1545         p->p_step = 1;
1546         CTR3(KTR_PTRACE, "stopevent: pid %d event %u val %u", p->p_pid, event,
1547             val);
1548         do {
1549                 if (event != S_EXIT)
1550                         p->p_xsig = val;
1551                 p->p_xthread = NULL;
1552                 p->p_stype = event;     /* Which event caused the stop? */
1553                 wakeup(&p->p_stype);    /* Wake up any PIOCWAIT'ing procs */
1554                 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0);
1555         } while (p->p_step);
1556 }