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/reg.h>
  44 #include <sys/syscallsubr.h>
  45 #include <sys/sysent.h>
  46 #include <sys/sysproto.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 #include <sys/caprights.h>
  56 #include <sys/filedesc.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 #endif
  72
  73 /* Assert it's safe to unlock a process, e.g. to allocate working memory */
  74 #define PROC_ASSERT_TRACEREQ(p) MPASS(((p)->p_flag2 & P2_PTRACEREQ) != 0)
  75
  76 /*
  77  * Functions implemented using PROC_ACTION():
  78  *
  79  * proc_read_regs(proc, regs)
  80  *      Get the current user-visible register set from the process
  81  *      and copy it into the regs structure (<machine/reg.h>).
  82  *      The process is stopped at the time read_regs is called.
  83  *
  84  * proc_write_regs(proc, regs)
  85  *      Update the current register set from the passed in regs
  86  *      structure.  Take care to avoid clobbering special CPU
  87  *      registers or privileged bits in the PSL.
  88  *      Depending on the architecture this may have fix-up work to do,
  89  *      especially if the IAR or PCW are modified.
  90  *      The process is stopped at the time write_regs is called.
  91  *
  92  * proc_read_fpregs, proc_write_fpregs
  93  *      deal with the floating point register set, otherwise as above.
  94  *
  95  * proc_read_dbregs, proc_write_dbregs
  96  *      deal with the processor debug register set, otherwise as above.
  97  *
  98  * proc_sstep(proc)
  99  *      Arrange for the process to trap after executing a single instruction.
 100  */
 101
 102 #define PROC_ACTION(action) do {                                        \
 103         int error;                                                      \
 104                                                                         \
 105         PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);                        \
 106         if ((td->td_proc->p_flag & P_INMEM) == 0)                       \
 107                 error = EIO;                                            \
 108         else                                                            \
 109                 error = (action);                                       \
 110         return (error);                                                 \
 111 } while(0)
 112
 113 int
 114 proc_read_regs(struct thread *td, struct reg *regs)
 115 {
 116
 117         PROC_ACTION(fill_regs(td, regs));
 118 }
 119
 120 int
 121 proc_write_regs(struct thread *td, struct reg *regs)
 122 {
 123
 124         PROC_ACTION(set_regs(td, regs));
 125 }
 126
 127 int
 128 proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
 129 {
 130
 131         PROC_ACTION(fill_dbregs(td, dbregs));
 132 }
 133
 134 int
 135 proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
 136 {
 137
 138         PROC_ACTION(set_dbregs(td, dbregs));
 139 }
 140
 141 /*
 142  * Ptrace doesn't support fpregs at all, and there are no security holes
 143  * or translations for fpregs, so we can just copy them.
 144  */
 145 int
 146 proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
 147 {
 148
 149         PROC_ACTION(fill_fpregs(td, fpregs));
 150 }
 151
 152 int
 153 proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
 154 {
 155
 156         PROC_ACTION(set_fpregs(td, fpregs));
 157 }
 158
 159 static struct regset *
 160 proc_find_regset(struct thread *td, int note)
 161 {
 162         struct regset **regsetp, **regset_end, *regset;
 163         struct sysentvec *sv;
 164
 165         sv = td->td_proc->p_sysent;
 166         regsetp = sv->sv_regset_begin;
 167         if (regsetp == NULL)
 168                 return (NULL);
 169         regset_end = sv->sv_regset_end;
 170         MPASS(regset_end != NULL);
 171         for (; regsetp < regset_end; regsetp++) {
 172                 regset = *regsetp;
 173                 if (regset->note != note)
 174                         continue;
 175
 176                 return (regset);
 177         }
 178
 179         return (NULL);
 180 }
 181
 182 static int
 183 proc_read_regset(struct thread *td, int note, struct iovec *iov)
 184 {
 185         struct regset *regset;
 186         struct proc *p;
 187         void *buf;
 188         size_t size;
 189         int error;
 190
 191         regset = proc_find_regset(td, note);
 192         if (regset == NULL)
 193                 return (EINVAL);
 194
 195         if (iov->iov_base == NULL) {
 196                 iov->iov_len = regset->size;
 197                 if (iov->iov_len == 0)
 198                         return (EINVAL);
 199
 200                 return (0);
 201         }
 202
 203         /* The length is wrong, return an error */
 204         if (iov->iov_len != regset->size)
 205                 return (EINVAL);
 206
 207         if (regset->get == NULL)
 208                 return (EINVAL);
 209
 210         error = 0;
 211         size = regset->size;
 212         p = td->td_proc;
 213
 214         /* Drop the proc lock while allocating the temp buffer */
 215         PROC_ASSERT_TRACEREQ(p);
 216         PROC_UNLOCK(p);
 217         buf = malloc(size, M_TEMP, M_WAITOK);
 218         PROC_LOCK(p);
 219
 220         if (!regset->get(regset, td, buf, &size)) {
 221                 error = EINVAL;
 222         } else {
 223                 KASSERT(size == regset->size,
 224                     ("%s: Getter function changed the size", __func__));
 225
 226                 iov->iov_len = size;
 227                 PROC_UNLOCK(p);
 228                 error = copyout(buf, iov->iov_base, size);
 229                 PROC_LOCK(p);
 230         }
 231
 232         free(buf, M_TEMP);
 233
 234         return (error);
 235 }
 236
 237 static int
 238 proc_write_regset(struct thread *td, int note, struct iovec *iov)
 239 {
 240         struct regset *regset;
 241         struct proc *p;
 242         void *buf;
 243         size_t size;
 244         int error;
 245
 246         regset = proc_find_regset(td, note);
 247         if (regset == NULL)
 248                 return (EINVAL);
 249
 250         /* The length is wrong, return an error */
 251         if (iov->iov_len != regset->size)
 252                 return (EINVAL);
 253
 254         if (regset->set == NULL)
 255                 return (EINVAL);
 256
 257         size = regset->size;
 258         p = td->td_proc;
 259
 260         /* Drop the proc lock while allocating the temp buffer */
 261         PROC_ASSERT_TRACEREQ(p);
 262         PROC_UNLOCK(p);
 263         buf = malloc(size, M_TEMP, M_WAITOK);
 264         error = copyin(iov->iov_base, buf, size);
 265         PROC_LOCK(p);
 266
 267         if (error == 0) {
 268                 if (!regset->set(regset, td, buf, size)) {
 269                         error = EINVAL;
 270                 }
 271         }
 272
 273         free(buf, M_TEMP);
 274
 275         return (error);
 276 }
 277
 278 #ifdef COMPAT_FREEBSD32
 279 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
 280 int
 281 proc_read_regs32(struct thread *td, struct reg32 *regs32)
 282 {
 283
 284         PROC_ACTION(fill_regs32(td, regs32));
 285 }
 286
 287 int
 288 proc_write_regs32(struct thread *td, struct reg32 *regs32)
 289 {
 290
 291         PROC_ACTION(set_regs32(td, regs32));
 292 }
 293
 294 int
 295 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 296 {
 297
 298         PROC_ACTION(fill_dbregs32(td, dbregs32));
 299 }
 300
 301 int
 302 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 303 {
 304
 305         PROC_ACTION(set_dbregs32(td, dbregs32));
 306 }
 307
 308 int
 309 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 310 {
 311
 312         PROC_ACTION(fill_fpregs32(td, fpregs32));
 313 }
 314
 315 int
 316 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 317 {
 318
 319         PROC_ACTION(set_fpregs32(td, fpregs32));
 320 }
 321 #endif
 322
 323 int
 324 proc_sstep(struct thread *td)
 325 {
 326
 327         PROC_ACTION(ptrace_single_step(td));
 328 }
 329
 330 int
 331 proc_rwmem(struct proc *p, struct uio *uio)
 332 {
 333         vm_map_t map;
 334         vm_offset_t pageno;             /* page number */
 335         vm_prot_t reqprot;
 336         int error, fault_flags, page_offset, writing;
 337
 338         /*
 339          * Make sure that the process' vmspace remains live.
 340          */
 341         if (p != curproc)
 342                 PROC_ASSERT_HELD(p);
 343         PROC_LOCK_ASSERT(p, MA_NOTOWNED);
 344
 345         /*
 346          * The map we want...
 347          */
 348         map = &p->p_vmspace->vm_map;
 349
 350         /*
 351          * If we are writing, then we request vm_fault() to create a private
 352          * copy of each page.  Since these copies will not be writeable by the
 353          * process, we must explicity request that they be dirtied.
 354          */
 355         writing = uio->uio_rw == UIO_WRITE;
 356         reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
 357         fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL;
 358
 359         /*
 360          * Only map in one page at a time.  We don't have to, but it
 361          * makes things easier.  This way is trivial - right?
 362          */
 363         do {
 364                 vm_offset_t uva;
 365                 u_int len;
 366                 vm_page_t m;
 367
 368                 uva = (vm_offset_t)uio->uio_offset;
 369
 370                 /*
 371                  * Get the page number of this segment.
 372                  */
 373                 pageno = trunc_page(uva);
 374                 page_offset = uva - pageno;
 375
 376                 /*
 377                  * How many bytes to copy
 378                  */
 379                 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
 380
 381                 /*
 382                  * Fault and hold the page on behalf of the process.
 383                  */
 384                 error = vm_fault(map, pageno, reqprot, fault_flags, &m);
 385                 if (error != KERN_SUCCESS) {
 386                         if (error == KERN_RESOURCE_SHORTAGE)
 387                                 error = ENOMEM;
 388                         else
 389                                 error = EFAULT;
 390                         break;
 391                 }
 392
 393                 /*
 394                  * Now do the i/o move.
 395                  */
 396                 error = uiomove_fromphys(&m, page_offset, len, uio);
 397
 398                 /* Make the I-cache coherent for breakpoints. */
 399                 if (writing && error == 0) {
 400                         vm_map_lock_read(map);
 401                         if (vm_map_check_protection(map, pageno, pageno +
 402                             PAGE_SIZE, VM_PROT_EXECUTE))
 403                                 vm_sync_icache(map, uva, len);
 404                         vm_map_unlock_read(map);
 405                 }
 406
 407                 /*
 408                  * Release the page.
 409                  */
 410                 vm_page_unwire(m, PQ_ACTIVE);
 411
 412         } while (error == 0 && uio->uio_resid > 0);
 413
 414         return (error);
 415 }
 416
 417 static ssize_t
 418 proc_iop(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 419     size_t len, enum uio_rw rw)
 420 {
 421         struct iovec iov;
 422         struct uio uio;
 423         ssize_t slen;
 424
 425         MPASS(len < SSIZE_MAX);
 426         slen = (ssize_t)len;
 427
 428         iov.iov_base = (caddr_t)buf;
 429         iov.iov_len = len;
 430         uio.uio_iov = &iov;
 431         uio.uio_iovcnt = 1;
 432         uio.uio_offset = va;
 433         uio.uio_resid = slen;
 434         uio.uio_segflg = UIO_SYSSPACE;
 435         uio.uio_rw = rw;
 436         uio.uio_td = td;
 437         proc_rwmem(p, &uio);
 438         if (uio.uio_resid == slen)
 439                 return (-1);
 440         return (slen - uio.uio_resid);
 441 }
 442
 443 ssize_t
 444 proc_readmem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 445     size_t len)
 446 {
 447
 448         return (proc_iop(td, p, va, buf, len, UIO_READ));
 449 }
 450
 451 ssize_t
 452 proc_writemem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
 453     size_t len)
 454 {
 455
 456         return (proc_iop(td, p, va, buf, len, UIO_WRITE));
 457 }
 458
 459 static int
 460 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
 461 {
 462         struct vattr vattr;
 463         vm_map_t map;
 464         vm_map_entry_t entry;
 465         vm_object_t obj, tobj, lobj;
 466         struct vmspace *vm;
 467         struct vnode *vp;
 468         char *freepath, *fullpath;
 469         u_int pathlen;
 470         int error, index;
 471
 472         error = 0;
 473         obj = NULL;
 474
 475         vm = vmspace_acquire_ref(p);
 476         map = &vm->vm_map;
 477         vm_map_lock_read(map);
 478
 479         do {
 480                 KASSERT((map->header.eflags & MAP_ENTRY_IS_SUB_MAP) == 0,
 481                     ("Submap in map header"));
 482                 index = 0;
 483                 VM_MAP_ENTRY_FOREACH(entry, map) {
 484                         if (index >= pve->pve_entry &&
 485                             (entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0)
 486                                 break;
 487                         index++;
 488                 }
 489                 if (index < pve->pve_entry) {
 490                         error = EINVAL;
 491                         break;
 492                 }
 493                 if (entry == &map->header) {
 494                         error = ENOENT;
 495                         break;
 496                 }
 497
 498                 /* We got an entry. */
 499                 pve->pve_entry = index + 1;
 500                 pve->pve_timestamp = map->timestamp;
 501                 pve->pve_start = entry->start;
 502                 pve->pve_end = entry->end - 1;
 503                 pve->pve_offset = entry->offset;
 504                 pve->pve_prot = entry->protection;
 505
 506                 /* Backing object's path needed? */
 507                 if (pve->pve_pathlen == 0)
 508                         break;
 509
 510                 pathlen = pve->pve_pathlen;
 511                 pve->pve_pathlen = 0;
 512
 513                 obj = entry->object.vm_object;
 514                 if (obj != NULL)
 515                         VM_OBJECT_RLOCK(obj);
 516         } while (0);
 517
 518         vm_map_unlock_read(map);
 519
 520         pve->pve_fsid = VNOVAL;
 521         pve->pve_fileid = VNOVAL;
 522
 523         if (error == 0 && obj != NULL) {
 524                 lobj = obj;
 525                 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
 526                         if (tobj != obj)
 527                                 VM_OBJECT_RLOCK(tobj);
 528                         if (lobj != obj)
 529                                 VM_OBJECT_RUNLOCK(lobj);
 530                         lobj = tobj;
 531                         pve->pve_offset += tobj->backing_object_offset;
 532                 }
 533                 vp = vm_object_vnode(lobj);
 534                 if (vp != NULL)
 535                         vref(vp);
 536                 if (lobj != obj)
 537                         VM_OBJECT_RUNLOCK(lobj);
 538                 VM_OBJECT_RUNLOCK(obj);
 539
 540                 if (vp != NULL) {
 541                         freepath = NULL;
 542                         fullpath = NULL;
 543                         vn_fullpath(vp, &fullpath, &freepath);
 544                         vn_lock(vp, LK_SHARED | LK_RETRY);
 545                         if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
 546                                 pve->pve_fileid = vattr.va_fileid;
 547                                 pve->pve_fsid = vattr.va_fsid;
 548                         }
 549                         vput(vp);
 550
 551                         if (fullpath != NULL) {
 552                                 pve->pve_pathlen = strlen(fullpath) + 1;
 553                                 if (pve->pve_pathlen <= pathlen) {
 554                                         error = copyout(fullpath, pve->pve_path,
 555                                             pve->pve_pathlen);
 556                                 } else
 557                                         error = ENAMETOOLONG;
 558                         }
 559                         if (freepath != NULL)
 560                                 free(freepath, M_TEMP);
 561                 }
 562         }
 563         vmspace_free(vm);
 564         if (error == 0)
 565                 CTR3(KTR_PTRACE, "PT_VM_ENTRY: pid %d, entry %d, start %p",
 566                     p->p_pid, pve->pve_entry, pve->pve_start);
 567
 568         return (error);
 569 }
 570
 571 /*
 572  * Process debugging system call.
 573  */
 574 #ifndef _SYS_SYSPROTO_H_
 575 struct ptrace_args {
 576         int     req;
 577         pid_t   pid;
 578         caddr_t addr;
 579         int     data;
 580 };
 581 #endif
 582
 583 int
 584 sys_ptrace(struct thread *td, struct ptrace_args *uap)
 585 {
 586         /*
 587          * XXX this obfuscation is to reduce stack usage, but the register
 588          * structs may be too large to put on the stack anyway.
 589          */
 590         union {
 591                 struct ptrace_io_desc piod;
 592                 struct ptrace_lwpinfo pl;
 593                 struct ptrace_vm_entry pve;
 594                 struct ptrace_coredump pc;
 595                 struct ptrace_sc_remote sr;
 596                 struct dbreg dbreg;
 597                 struct fpreg fpreg;
 598                 struct reg reg;
 599                 struct iovec vec;
 600                 char args[sizeof(td->td_sa.args)];
 601                 struct ptrace_sc_ret psr;
 602                 int ptevents;
 603         } r;
 604         register_t pscr_args[nitems(td->td_sa.args)];
 605         void *addr;
 606         int error;
 607
 608         if (!allow_ptrace)
 609                 return (ENOSYS);
 610         error = 0;
 611
 612         AUDIT_ARG_PID(uap->pid);
 613         AUDIT_ARG_CMD(uap->req);
 614         AUDIT_ARG_VALUE(uap->data);
 615         addr = &r;
 616         switch (uap->req) {
 617         case PT_GET_EVENT_MASK:
 618         case PT_LWPINFO:
 619         case PT_GET_SC_ARGS:
 620         case PT_GET_SC_RET:
 621                 break;
 622         case PT_GETREGS:
 623                 bzero(&r.reg, sizeof(r.reg));
 624                 break;
 625         case PT_GETFPREGS:
 626                 bzero(&r.fpreg, sizeof(r.fpreg));
 627                 break;
 628         case PT_GETDBREGS:
 629                 bzero(&r.dbreg, sizeof(r.dbreg));
 630                 break;
 631         case PT_GETREGSET:
 632         case PT_SETREGSET:
 633                 error = copyin(uap->addr, &r.vec, sizeof(r.vec));
 634                 break;
 635         case PT_SETREGS:
 636                 error = copyin(uap->addr, &r.reg, sizeof(r.reg));
 637                 break;
 638         case PT_SETFPREGS:
 639                 error = copyin(uap->addr, &r.fpreg, sizeof(r.fpreg));
 640                 break;
 641         case PT_SETDBREGS:
 642                 error = copyin(uap->addr, &r.dbreg, sizeof(r.dbreg));
 643                 break;
 644         case PT_SET_EVENT_MASK:
 645                 if (uap->data != sizeof(r.ptevents))
 646                         error = EINVAL;
 647                 else
 648                         error = copyin(uap->addr, &r.ptevents, uap->data);
 649                 break;
 650         case PT_IO:
 651                 error = copyin(uap->addr, &r.piod, sizeof(r.piod));
 652                 break;
 653         case PT_VM_ENTRY:
 654                 error = copyin(uap->addr, &r.pve, sizeof(r.pve));
 655                 break;
 656         case PT_COREDUMP:
 657                 if (uap->data != sizeof(r.pc))
 658                         error = EINVAL;
 659                 else
 660                         error = copyin(uap->addr, &r.pc, uap->data);
 661                 break;
 662         case PT_SC_REMOTE:
 663                 if (uap->data != sizeof(r.sr)) {
 664                         error = EINVAL;
 665                         break;
 666                 }
 667                 error = copyin(uap->addr, &r.sr, uap->data);
 668                 if (error != 0)
 669                         break;
 670                 if (r.sr.pscr_nargs > nitems(td->td_sa.args)) {
 671                         error = EINVAL;
 672                         break;
 673                 }
 674                 error = copyin(r.sr.pscr_args, pscr_args,
 675                     sizeof(u_long) * r.sr.pscr_nargs);
 676                 if (error != 0)
 677                         break;
 678                 r.sr.pscr_args = pscr_args;
 679                 break;
 680         default:
 681                 addr = uap->addr;
 682                 break;
 683         }
 684         if (error)
 685                 return (error);
 686
 687         error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
 688         if (error)
 689                 return (error);
 690
 691         switch (uap->req) {
 692         case PT_VM_ENTRY:
 693                 error = copyout(&r.pve, uap->addr, sizeof(r.pve));
 694                 break;
 695         case PT_IO:
 696                 error = copyout(&r.piod, uap->addr, sizeof(r.piod));
 697                 break;
 698         case PT_GETREGS:
 699                 error = copyout(&r.reg, uap->addr, sizeof(r.reg));
 700                 break;
 701         case PT_GETFPREGS:
 702                 error = copyout(&r.fpreg, uap->addr, sizeof(r.fpreg));
 703                 break;
 704         case PT_GETDBREGS:
 705                 error = copyout(&r.dbreg, uap->addr, sizeof(r.dbreg));
 706                 break;
 707         case PT_GETREGSET:
 708                 error = copyout(&r.vec, uap->addr, sizeof(r.vec));
 709                 break;
 710         case PT_GET_EVENT_MASK:
 711                 /* NB: The size in uap->data is validated in kern_ptrace(). */
 712                 error = copyout(&r.ptevents, uap->addr, uap->data);
 713                 break;
 714         case PT_LWPINFO:
 715                 /* NB: The size in uap->data is validated in kern_ptrace(). */
 716                 error = copyout(&r.pl, uap->addr, uap->data);
 717                 break;
 718         case PT_GET_SC_ARGS:
 719                 error = copyout(r.args, uap->addr, MIN(uap->data,
 720                     sizeof(r.args)));
 721                 break;
 722         case PT_GET_SC_RET:
 723                 error = copyout(&r.psr, uap->addr, MIN(uap->data,
 724                     sizeof(r.psr)));
 725                 break;
 726         case PT_SC_REMOTE:
 727                 error = copyout(&r.sr.pscr_ret, uap->addr +
 728                     offsetof(struct ptrace_sc_remote, pscr_ret),
 729                     sizeof(r.sr.pscr_ret));
 730                 break;
 731         }
 732
 733         return (error);
 734 }
 735
 736 #ifdef COMPAT_FREEBSD32
 737 /*
 738  *   PROC_READ(regs, td2, addr);
 739  * becomes either:
 740  *   proc_read_regs(td2, addr);
 741  * or
 742  *   proc_read_regs32(td2, addr);
 743  * .. except this is done at runtime.  There is an additional
 744  * complication in that PROC_WRITE disallows 32 bit consumers
 745  * from writing to 64 bit address space targets.
 746  */
 747 #define PROC_READ(w, t, a)      wrap32 ? \
 748         proc_read_ ## w ## 32(t, a) : \
 749         proc_read_ ## w (t, a)
 750 #define PROC_WRITE(w, t, a)     wrap32 ? \
 751         (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
 752         proc_write_ ## w (t, a)
 753 #else
 754 #define PROC_READ(w, t, a)      proc_read_ ## w (t, a)
 755 #define PROC_WRITE(w, t, a)     proc_write_ ## w (t, a)
 756 #endif
 757
 758 void
 759 proc_set_traced(struct proc *p, bool stop)
 760 {
 761
 762         sx_assert(&proctree_lock, SX_XLOCKED);
 763         PROC_LOCK_ASSERT(p, MA_OWNED);
 764         p->p_flag |= P_TRACED;
 765         if (stop)
 766                 p->p_flag2 |= P2_PTRACE_FSTP;
 767         p->p_ptevents = PTRACE_DEFAULT;
 768 }
 769
 770 void
 771 ptrace_unsuspend(struct proc *p)
 772 {
 773         PROC_LOCK_ASSERT(p, MA_OWNED);
 774
 775         PROC_SLOCK(p);
 776         p->p_flag &= ~(P_STOPPED_TRACE | P_STOPPED_SIG | P_WAITED);
 777         thread_unsuspend(p);
 778         PROC_SUNLOCK(p);
 779         itimer_proc_continue(p);
 780         kqtimer_proc_continue(p);
 781 }
 782
 783 static int
 784 proc_can_ptrace(struct thread *td, struct proc *p)
 785 {
 786         int error;
 787
 788         PROC_LOCK_ASSERT(p, MA_OWNED);
 789
 790         if ((p->p_flag & P_WEXIT) != 0)
 791                 return (ESRCH);
 792
 793         if ((error = p_cansee(td, p)) != 0)
 794                 return (error);
 795         if ((error = p_candebug(td, p)) != 0)
 796                 return (error);
 797
 798         /* not being traced... */
 799         if ((p->p_flag & P_TRACED) == 0)
 800                 return (EPERM);
 801
 802         /* not being traced by YOU */
 803         if (p->p_pptr != td->td_proc)
 804                 return (EBUSY);
 805
 806         /* not currently stopped */
 807         if ((p->p_flag & P_STOPPED_TRACE) == 0 ||
 808             p->p_suspcount != p->p_numthreads  ||
 809             (p->p_flag & P_WAITED) == 0)
 810                 return (EBUSY);
 811
 812         return (0);
 813 }
 814
 815 static struct thread *
 816 ptrace_sel_coredump_thread(struct proc *p)
 817 {
 818         struct thread *td2;
 819
 820         PROC_LOCK_ASSERT(p, MA_OWNED);
 821         MPASS((p->p_flag & P_STOPPED_TRACE) != 0);
 822
 823         FOREACH_THREAD_IN_PROC(p, td2) {
 824                 if ((td2->td_dbgflags & TDB_SSWITCH) != 0)
 825                         return (td2);
 826         }
 827         return (NULL);
 828 }
 829
 830 int
 831 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 832 {
 833         struct iovec iov;
 834         struct uio uio;
 835         struct proc *curp, *p, *pp;
 836         struct thread *td2 = NULL, *td3;
 837         struct ptrace_io_desc *piod = NULL;
 838         struct ptrace_lwpinfo *pl;
 839         struct ptrace_sc_ret *psr;
 840         struct ptrace_sc_remote *pscr;
 841         struct file *fp;
 842         struct ptrace_coredump *pc;
 843         struct thr_coredump_req *tcq;
 844         struct thr_syscall_req *tsr;
 845         int error, num, tmp;
 846         lwpid_t tid = 0, *buf;
 847 #ifdef COMPAT_FREEBSD32
 848         int wrap32 = 0, safe = 0;
 849 #endif
 850         bool proctree_locked, p2_req_set;
 851
 852         curp = td->td_proc;
 853         proctree_locked = false;
 854         p2_req_set = false;
 855
 856         /* Lock proctree before locking the process. */
 857         switch (req) {
 858         case PT_TRACE_ME:
 859         case PT_ATTACH:
 860         case PT_STEP:
 861         case PT_CONTINUE:
 862         case PT_TO_SCE:
 863         case PT_TO_SCX:
 864         case PT_SYSCALL:
 865         case PT_FOLLOW_FORK:
 866         case PT_LWP_EVENTS:
 867         case PT_GET_EVENT_MASK:
 868         case PT_SET_EVENT_MASK:
 869         case PT_DETACH:
 870         case PT_GET_SC_ARGS:
 871                 sx_xlock(&proctree_lock);
 872                 proctree_locked = true;
 873                 break;
 874         default:
 875                 break;
 876         }
 877
 878         if (req == PT_TRACE_ME) {
 879                 p = td->td_proc;
 880                 PROC_LOCK(p);
 881         } else {
 882                 if (pid <= PID_MAX) {
 883                         if ((p = pfind(pid)) == NULL) {
 884                                 if (proctree_locked)
 885                                         sx_xunlock(&proctree_lock);
 886                                 return (ESRCH);
 887                         }
 888                 } else {
 889                         td2 = tdfind(pid, -1);
 890                         if (td2 == NULL) {
 891                                 if (proctree_locked)
 892                                         sx_xunlock(&proctree_lock);
 893                                 return (ESRCH);
 894                         }
 895                         p = td2->td_proc;
 896                         tid = pid;
 897                         pid = p->p_pid;
 898                 }
 899         }
 900         AUDIT_ARG_PROCESS(p);
 901
 902         if ((p->p_flag & P_WEXIT) != 0) {
 903                 error = ESRCH;
 904                 goto fail;
 905         }
 906         if ((error = p_cansee(td, p)) != 0)
 907                 goto fail;
 908
 909         if ((error = p_candebug(td, p)) != 0)
 910                 goto fail;
 911
 912         /*
 913          * System processes can't be debugged.
 914          */
 915         if ((p->p_flag & P_SYSTEM) != 0) {
 916                 error = EINVAL;
 917                 goto fail;
 918         }
 919
 920         if (tid == 0) {
 921                 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
 922                         KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
 923                         td2 = p->p_xthread;
 924                 } else {
 925                         td2 = FIRST_THREAD_IN_PROC(p);
 926                 }
 927                 tid = td2->td_tid;
 928         }
 929
 930 #ifdef COMPAT_FREEBSD32
 931         /*
 932          * Test if we're a 32 bit client and what the target is.
 933          * Set the wrap controls accordingly.
 934          */
 935         if (SV_CURPROC_FLAG(SV_ILP32)) {
 936                 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32))
 937                         safe = 1;
 938                 wrap32 = 1;
 939         }
 940 #endif
 941         /*
 942          * Permissions check
 943          */
 944         switch (req) {
 945         case PT_TRACE_ME:
 946                 /*
 947                  * Always legal, when there is a parent process which
 948                  * could trace us.  Otherwise, reject.
 949                  */
 950                 if ((p->p_flag & P_TRACED) != 0) {
 951                         error = EBUSY;
 952                         goto fail;
 953                 }
 954                 if (p->p_pptr == initproc) {
 955                         error = EPERM;
 956                         goto fail;
 957                 }
 958                 break;
 959
 960         case PT_ATTACH:
 961                 /* Self */
 962                 if (p == td->td_proc) {
 963                         error = EINVAL;
 964                         goto fail;
 965                 }
 966
 967                 /* Already traced */
 968                 if (p->p_flag & P_TRACED) {
 969                         error = EBUSY;
 970                         goto fail;
 971                 }
 972
 973                 /* Can't trace an ancestor if you're being traced. */
 974                 if (curp->p_flag & P_TRACED) {
 975                         for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
 976                                 if (pp == p) {
 977                                         error = EINVAL;
 978                                         goto fail;
 979                                 }
 980                         }
 981                 }
 982
 983                 /* OK */
 984                 break;
 985
 986         case PT_CLEARSTEP:
 987                 /* Allow thread to clear single step for itself */
 988                 if (td->td_tid == tid)
 989                         break;
 990
 991                 /* FALLTHROUGH */
 992         default:
 993                 /*
 994                  * Check for ptrace eligibility before waiting for
 995                  * holds to drain.
 996                  */
 997                 error = proc_can_ptrace(td, p);
 998                 if (error != 0)
 999                         goto fail;
1000
1001                 /*
1002                  * Block parallel ptrace requests.  Most important, do
1003                  * not allow other thread in debugger to continue the
1004                  * debuggee until coredump finished.
1005                  */
1006                 while ((p->p_flag2 & P2_PTRACEREQ) != 0) {
1007                         if (proctree_locked)
1008                                 sx_xunlock(&proctree_lock);
1009                         error = msleep(&p->p_flag2, &p->p_mtx, PPAUSE | PCATCH |
1010                             (proctree_locked ? PDROP : 0), "pptrace", 0);
1011                         if (proctree_locked) {
1012                                 sx_xlock(&proctree_lock);
1013                                 PROC_LOCK(p);
1014                         }
1015                         if (error == 0 && td2->td_proc != p)
1016                                 error = ESRCH;
1017                         if (error == 0)
1018                                 error = proc_can_ptrace(td, p);
1019                         if (error != 0)
1020                                 goto fail;
1021                 }
1022
1023                 /* Ok */
1024                 break;
1025         }
1026
1027         /*
1028          * Keep this process around and request parallel ptrace()
1029          * request to wait until we finish this request.
1030          */
1031         MPASS((p->p_flag2 & P2_PTRACEREQ) == 0);
1032         p->p_flag2 |= P2_PTRACEREQ;
1033         p2_req_set = true;
1034         _PHOLD(p);
1035
1036         /*
1037          * Actually do the requests
1038          */
1039
1040         td->td_retval[0] = 0;
1041
1042         switch (req) {
1043         case PT_TRACE_ME:
1044                 /* set my trace flag and "owner" so it can read/write me */
1045                 proc_set_traced(p, false);
1046                 if (p->p_flag & P_PPWAIT)
1047                         p->p_flag |= P_PPTRACE;
1048                 CTR1(KTR_PTRACE, "PT_TRACE_ME: pid %d", p->p_pid);
1049                 break;
1050
1051         case PT_ATTACH:
1052                 /* security check done above */
1053                 /*
1054                  * It would be nice if the tracing relationship was separate
1055                  * from the parent relationship but that would require
1056                  * another set of links in the proc struct or for "wait"
1057                  * to scan the entire proc table.  To make life easier,
1058                  * we just re-parent the process we're trying to trace.
1059                  * The old parent is remembered so we can put things back
1060                  * on a "detach".
1061                  */
1062                 proc_set_traced(p, true);
1063                 proc_reparent(p, td->td_proc, false);
1064                 CTR2(KTR_PTRACE, "PT_ATTACH: pid %d, oppid %d", p->p_pid,
1065                     p->p_oppid);
1066
1067                 sx_xunlock(&proctree_lock);
1068                 proctree_locked = false;
1069                 MPASS(p->p_xthread == NULL);
1070                 MPASS((p->p_flag & P_STOPPED_TRACE) == 0);
1071
1072                 /*
1073                  * If already stopped due to a stop signal, clear the
1074                  * existing stop before triggering a traced SIGSTOP.
1075                  */
1076                 if ((p->p_flag & P_STOPPED_SIG) != 0) {
1077                         PROC_SLOCK(p);
1078                         p->p_flag &= ~(P_STOPPED_SIG | P_WAITED);
1079                         thread_unsuspend(p);
1080                         PROC_SUNLOCK(p);
1081                 }
1082
1083                 kern_psignal(p, SIGSTOP);
1084                 break;
1085
1086         case PT_CLEARSTEP:
1087                 CTR2(KTR_PTRACE, "PT_CLEARSTEP: tid %d (pid %d)", td2->td_tid,
1088                     p->p_pid);
1089                 error = ptrace_clear_single_step(td2);
1090                 break;
1091
1092         case PT_SETSTEP:
1093                 CTR2(KTR_PTRACE, "PT_SETSTEP: tid %d (pid %d)", td2->td_tid,
1094                     p->p_pid);
1095                 error = ptrace_single_step(td2);
1096                 break;
1097
1098         case PT_SUSPEND:
1099                 CTR2(KTR_PTRACE, "PT_SUSPEND: tid %d (pid %d)", td2->td_tid,
1100                     p->p_pid);
1101                 td2->td_dbgflags |= TDB_SUSPEND;
1102                 thread_lock(td2);
1103                 td2->td_flags |= TDF_NEEDSUSPCHK;
1104                 thread_unlock(td2);
1105                 break;
1106
1107         case PT_RESUME:
1108                 CTR2(KTR_PTRACE, "PT_RESUME: tid %d (pid %d)", td2->td_tid,
1109                     p->p_pid);
1110                 td2->td_dbgflags &= ~TDB_SUSPEND;
1111                 break;
1112
1113         case PT_FOLLOW_FORK:
1114                 CTR3(KTR_PTRACE, "PT_FOLLOW_FORK: pid %d %s -> %s", p->p_pid,
1115                     p->p_ptevents & PTRACE_FORK ? "enabled" : "disabled",
1116                     data ? "enabled" : "disabled");
1117                 if (data)
1118                         p->p_ptevents |= PTRACE_FORK;
1119                 else
1120                         p->p_ptevents &= ~PTRACE_FORK;
1121                 break;
1122
1123         case PT_LWP_EVENTS:
1124                 CTR3(KTR_PTRACE, "PT_LWP_EVENTS: pid %d %s -> %s", p->p_pid,
1125                     p->p_ptevents & PTRACE_LWP ? "enabled" : "disabled",
1126                     data ? "enabled" : "disabled");
1127                 if (data)
1128                         p->p_ptevents |= PTRACE_LWP;
1129                 else
1130                         p->p_ptevents &= ~PTRACE_LWP;
1131                 break;
1132
1133         case PT_GET_EVENT_MASK:
1134                 if (data != sizeof(p->p_ptevents)) {
1135                         error = EINVAL;
1136                         break;
1137                 }
1138                 CTR2(KTR_PTRACE, "PT_GET_EVENT_MASK: pid %d mask %#x", p->p_pid,
1139                     p->p_ptevents);
1140                 *(int *)addr = p->p_ptevents;
1141                 break;
1142
1143         case PT_SET_EVENT_MASK:
1144                 if (data != sizeof(p->p_ptevents)) {
1145                         error = EINVAL;
1146                         break;
1147                 }
1148                 tmp = *(int *)addr;
1149                 if ((tmp & ~(PTRACE_EXEC | PTRACE_SCE | PTRACE_SCX |
1150                     PTRACE_FORK | PTRACE_LWP | PTRACE_VFORK)) != 0) {
1151                         error = EINVAL;
1152                         break;
1153                 }
1154                 CTR3(KTR_PTRACE, "PT_SET_EVENT_MASK: pid %d mask %#x -> %#x",
1155                     p->p_pid, p->p_ptevents, tmp);
1156                 p->p_ptevents = tmp;
1157                 break;
1158
1159         case PT_GET_SC_ARGS:
1160                 CTR1(KTR_PTRACE, "PT_GET_SC_ARGS: pid %d", p->p_pid);
1161                 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) == 0
1162 #ifdef COMPAT_FREEBSD32
1163                     || (wrap32 && !safe)
1164 #endif
1165                     ) {
1166                         error = EINVAL;
1167                         break;
1168                 }
1169                 bzero(addr, sizeof(td2->td_sa.args));
1170                 /* See the explanation in linux_ptrace_get_syscall_info(). */
1171                 bcopy(td2->td_sa.args, addr, SV_PROC_ABI(td->td_proc) ==
1172                     SV_ABI_LINUX ? sizeof(td2->td_sa.args) :
1173                     td2->td_sa.callp->sy_narg * sizeof(register_t));
1174                 break;
1175
1176         case PT_GET_SC_RET:
1177                 if ((td2->td_dbgflags & (TDB_SCX)) == 0
1178 #ifdef COMPAT_FREEBSD32
1179                     || (wrap32 && !safe)
1180 #endif
1181                     ) {
1182                         error = EINVAL;
1183                         break;
1184                 }
1185                 psr = addr;
1186                 bzero(psr, sizeof(*psr));
1187                 psr->sr_error = td2->td_errno;
1188                 if (psr->sr_error == 0) {
1189                         psr->sr_retval[0] = td2->td_retval[0];
1190                         psr->sr_retval[1] = td2->td_retval[1];
1191                 }
1192                 CTR4(KTR_PTRACE,
1193                     "PT_GET_SC_RET: pid %d error %d retval %#lx,%#lx",
1194                     p->p_pid, psr->sr_error, psr->sr_retval[0],
1195                     psr->sr_retval[1]);
1196                 break;
1197
1198         case PT_STEP:
1199         case PT_CONTINUE:
1200         case PT_TO_SCE:
1201         case PT_TO_SCX:
1202         case PT_SYSCALL:
1203         case PT_DETACH:
1204                 /* Zero means do not send any signal */
1205                 if (data < 0 || data > _SIG_MAXSIG) {
1206                         error = EINVAL;
1207                         break;
1208                 }
1209
1210                 switch (req) {
1211                 case PT_STEP:
1212                         CTR3(KTR_PTRACE, "PT_STEP: tid %d (pid %d), sig = %d",
1213                             td2->td_tid, p->p_pid, data);
1214                         error = ptrace_single_step(td2);
1215                         if (error)
1216                                 goto out;
1217                         break;
1218                 case PT_CONTINUE:
1219                 case PT_TO_SCE:
1220                 case PT_TO_SCX:
1221                 case PT_SYSCALL:
1222                         if (addr != (void *)1) {
1223                                 error = ptrace_set_pc(td2,
1224                                     (u_long)(uintfptr_t)addr);
1225                                 if (error)
1226                                         goto out;
1227                         }
1228                         switch (req) {
1229                         case PT_TO_SCE:
1230                                 p->p_ptevents |= PTRACE_SCE;
1231                                 CTR4(KTR_PTRACE,
1232                     "PT_TO_SCE: pid %d, events = %#x, PC = %#lx, sig = %d",
1233                                     p->p_pid, p->p_ptevents,
1234                                     (u_long)(uintfptr_t)addr, data);
1235                                 break;
1236                         case PT_TO_SCX:
1237                                 p->p_ptevents |= PTRACE_SCX;
1238                                 CTR4(KTR_PTRACE,
1239                     "PT_TO_SCX: pid %d, events = %#x, PC = %#lx, sig = %d",
1240                                     p->p_pid, p->p_ptevents,
1241                                     (u_long)(uintfptr_t)addr, data);
1242                                 break;
1243                         case PT_SYSCALL:
1244                                 p->p_ptevents |= PTRACE_SYSCALL;
1245                                 CTR4(KTR_PTRACE,
1246                     "PT_SYSCALL: pid %d, events = %#x, PC = %#lx, sig = %d",
1247                                     p->p_pid, p->p_ptevents,
1248                                     (u_long)(uintfptr_t)addr, data);
1249                                 break;
1250                         case PT_CONTINUE:
1251                                 CTR3(KTR_PTRACE,
1252                                     "PT_CONTINUE: pid %d, PC = %#lx, sig = %d",
1253                                     p->p_pid, (u_long)(uintfptr_t)addr, data);
1254                                 break;
1255                         }
1256                         break;
1257                 case PT_DETACH:
1258                         /*
1259                          * Clear P_TRACED before reparenting
1260                          * a detached process back to its original
1261                          * parent.  Otherwise the debugee will be set
1262                          * as an orphan of the debugger.
1263                          */
1264                         p->p_flag &= ~(P_TRACED | P_WAITED);
1265
1266                         /*
1267                          * Reset the process parent.
1268                          */
1269                         if (p->p_oppid != p->p_pptr->p_pid) {
1270                                 PROC_LOCK(p->p_pptr);
1271                                 sigqueue_take(p->p_ksi);
1272                                 PROC_UNLOCK(p->p_pptr);
1273
1274                                 pp = proc_realparent(p);
1275                                 proc_reparent(p, pp, false);
1276                                 if (pp == initproc)
1277                                         p->p_sigparent = SIGCHLD;
1278                                 CTR3(KTR_PTRACE,
1279                             "PT_DETACH: pid %d reparented to pid %d, sig %d",
1280                                     p->p_pid, pp->p_pid, data);
1281                         } else {
1282                                 CTR2(KTR_PTRACE, "PT_DETACH: pid %d, sig %d",
1283                                     p->p_pid, data);
1284                         }
1285
1286                         p->p_ptevents = 0;
1287                         FOREACH_THREAD_IN_PROC(p, td3) {
1288                                 if ((td3->td_dbgflags & TDB_FSTP) != 0) {
1289                                         sigqueue_delete(&td3->td_sigqueue,
1290                                             SIGSTOP);
1291                                 }
1292                                 td3->td_dbgflags &= ~(TDB_XSIG | TDB_FSTP |
1293                                     TDB_SUSPEND);
1294                         }
1295
1296                         if ((p->p_flag2 & P2_PTRACE_FSTP) != 0) {
1297                                 sigqueue_delete(&p->p_sigqueue, SIGSTOP);
1298                                 p->p_flag2 &= ~P2_PTRACE_FSTP;
1299                         }
1300
1301                         /* should we send SIGCHLD? */
1302                         /* childproc_continued(p); */
1303                         break;
1304                 }
1305
1306                 sx_xunlock(&proctree_lock);
1307                 proctree_locked = false;
1308
1309         sendsig:
1310                 MPASS(!proctree_locked);
1311
1312                 /*
1313                  * Clear the pending event for the thread that just
1314                  * reported its event (p_xthread).  This may not be
1315                  * the thread passed to PT_CONTINUE, PT_STEP, etc. if
1316                  * the debugger is resuming a different thread.
1317                  *
1318                  * Deliver any pending signal via the reporting thread.
1319                  */
1320                 MPASS(p->p_xthread != NULL);
1321                 p->p_xthread->td_dbgflags &= ~TDB_XSIG;
1322                 p->p_xthread->td_xsig = data;
1323                 p->p_xthread = NULL;
1324                 p->p_xsig = data;
1325
1326                 /*
1327                  * P_WKILLED is insurance that a PT_KILL/SIGKILL
1328                  * always works immediately, even if another thread is
1329                  * unsuspended first and attempts to handle a
1330                  * different signal or if the POSIX.1b style signal
1331                  * queue cannot accommodate any new signals.
1332                  */
1333                 if (data == SIGKILL)
1334                         proc_wkilled(p);
1335
1336                 /*
1337                  * Unsuspend all threads.  To leave a thread
1338                  * suspended, use PT_SUSPEND to suspend it before
1339                  * continuing the process.
1340                  */
1341                 ptrace_unsuspend(p);
1342                 break;
1343
1344         case PT_WRITE_I:
1345         case PT_WRITE_D:
1346                 td2->td_dbgflags |= TDB_USERWR;
1347                 PROC_UNLOCK(p);
1348                 error = 0;
1349                 if (proc_writemem(td, p, (off_t)(uintptr_t)addr, &data,
1350                     sizeof(int)) != sizeof(int))
1351                         error = ENOMEM;
1352                 else
1353                         CTR3(KTR_PTRACE, "PT_WRITE: pid %d: %p <= %#x",
1354                             p->p_pid, addr, data);
1355                 PROC_LOCK(p);
1356                 break;
1357
1358         case PT_READ_I:
1359         case PT_READ_D:
1360                 PROC_UNLOCK(p);
1361                 error = tmp = 0;
1362                 if (proc_readmem(td, p, (off_t)(uintptr_t)addr, &tmp,
1363                     sizeof(int)) != sizeof(int))
1364                         error = ENOMEM;
1365                 else
1366                         CTR3(KTR_PTRACE, "PT_READ: pid %d: %p >= %#x",
1367                             p->p_pid, addr, tmp);
1368                 td->td_retval[0] = tmp;
1369                 PROC_LOCK(p);
1370                 break;
1371
1372         case PT_IO:
1373                 piod = addr;
1374                 iov.iov_base = piod->piod_addr;
1375                 iov.iov_len = piod->piod_len;
1376                 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
1377                 uio.uio_resid = piod->piod_len;
1378                 uio.uio_iov = &iov;
1379                 uio.uio_iovcnt = 1;
1380                 uio.uio_segflg = UIO_USERSPACE;
1381                 uio.uio_td = td;
1382                 switch (piod->piod_op) {
1383                 case PIOD_READ_D:
1384                 case PIOD_READ_I:
1385                         CTR3(KTR_PTRACE, "PT_IO: pid %d: READ (%p, %#x)",
1386                             p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1387                         uio.uio_rw = UIO_READ;
1388                         break;
1389                 case PIOD_WRITE_D:
1390                 case PIOD_WRITE_I:
1391                         CTR3(KTR_PTRACE, "PT_IO: pid %d: WRITE (%p, %#x)",
1392                             p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1393                         td2->td_dbgflags |= TDB_USERWR;
1394                         uio.uio_rw = UIO_WRITE;
1395                         break;
1396                 default:
1397                         error = EINVAL;
1398                         goto out;
1399                 }
1400                 PROC_UNLOCK(p);
1401                 error = proc_rwmem(p, &uio);
1402                 piod->piod_len -= uio.uio_resid;
1403                 PROC_LOCK(p);
1404                 break;
1405
1406         case PT_KILL:
1407                 CTR1(KTR_PTRACE, "PT_KILL: pid %d", p->p_pid);
1408                 data = SIGKILL;
1409                 goto sendsig;   /* in PT_CONTINUE above */
1410
1411         case PT_SETREGS:
1412                 CTR2(KTR_PTRACE, "PT_SETREGS: tid %d (pid %d)", td2->td_tid,
1413                     p->p_pid);
1414                 td2->td_dbgflags |= TDB_USERWR;
1415                 error = PROC_WRITE(regs, td2, addr);
1416                 break;
1417
1418         case PT_GETREGS:
1419                 CTR2(KTR_PTRACE, "PT_GETREGS: tid %d (pid %d)", td2->td_tid,
1420                     p->p_pid);
1421                 error = PROC_READ(regs, td2, addr);
1422                 break;
1423
1424         case PT_SETFPREGS:
1425                 CTR2(KTR_PTRACE, "PT_SETFPREGS: tid %d (pid %d)", td2->td_tid,
1426                     p->p_pid);
1427                 td2->td_dbgflags |= TDB_USERWR;
1428                 error = PROC_WRITE(fpregs, td2, addr);
1429                 break;
1430
1431         case PT_GETFPREGS:
1432                 CTR2(KTR_PTRACE, "PT_GETFPREGS: tid %d (pid %d)", td2->td_tid,
1433                     p->p_pid);
1434                 error = PROC_READ(fpregs, td2, addr);
1435                 break;
1436
1437         case PT_SETDBREGS:
1438                 CTR2(KTR_PTRACE, "PT_SETDBREGS: tid %d (pid %d)", td2->td_tid,
1439                     p->p_pid);
1440                 td2->td_dbgflags |= TDB_USERWR;
1441                 error = PROC_WRITE(dbregs, td2, addr);
1442                 break;
1443
1444         case PT_GETDBREGS:
1445                 CTR2(KTR_PTRACE, "PT_GETDBREGS: tid %d (pid %d)", td2->td_tid,
1446                     p->p_pid);
1447                 error = PROC_READ(dbregs, td2, addr);
1448                 break;
1449
1450         case PT_SETREGSET:
1451                 CTR2(KTR_PTRACE, "PT_SETREGSET: tid %d (pid %d)", td2->td_tid,
1452                     p->p_pid);
1453                 error = proc_write_regset(td2, data, addr);
1454                 break;
1455
1456         case PT_GETREGSET:
1457                 CTR2(KTR_PTRACE, "PT_GETREGSET: tid %d (pid %d)", td2->td_tid,
1458                     p->p_pid);
1459                 error = proc_read_regset(td2, data, addr);
1460                 break;
1461
1462         case PT_LWPINFO:
1463                 if (data <= 0 || data > sizeof(*pl)) {
1464                         error = EINVAL;
1465                         break;
1466                 }
1467                 pl = addr;
1468                 bzero(pl, sizeof(*pl));
1469                 pl->pl_lwpid = td2->td_tid;
1470                 pl->pl_event = PL_EVENT_NONE;
1471                 pl->pl_flags = 0;
1472                 if (td2->td_dbgflags & TDB_XSIG) {
1473                         pl->pl_event = PL_EVENT_SIGNAL;
1474                         if (td2->td_si.si_signo != 0 &&
1475                             data >= offsetof(struct ptrace_lwpinfo, pl_siginfo)
1476                             + sizeof(pl->pl_siginfo)){
1477                                 pl->pl_flags |= PL_FLAG_SI;
1478                                 pl->pl_siginfo = td2->td_si;
1479                         }
1480                 }
1481                 if (td2->td_dbgflags & TDB_SCE)
1482                         pl->pl_flags |= PL_FLAG_SCE;
1483                 else if (td2->td_dbgflags & TDB_SCX)
1484                         pl->pl_flags |= PL_FLAG_SCX;
1485                 if (td2->td_dbgflags & TDB_EXEC)
1486                         pl->pl_flags |= PL_FLAG_EXEC;
1487                 if (td2->td_dbgflags & TDB_FORK) {
1488                         pl->pl_flags |= PL_FLAG_FORKED;
1489                         pl->pl_child_pid = td2->td_dbg_forked;
1490                         if (td2->td_dbgflags & TDB_VFORK)
1491                                 pl->pl_flags |= PL_FLAG_VFORKED;
1492                 } else if ((td2->td_dbgflags & (TDB_SCX | TDB_VFORK)) ==
1493                     TDB_VFORK)
1494                         pl->pl_flags |= PL_FLAG_VFORK_DONE;
1495                 if (td2->td_dbgflags & TDB_CHILD)
1496                         pl->pl_flags |= PL_FLAG_CHILD;
1497                 if (td2->td_dbgflags & TDB_BORN)
1498                         pl->pl_flags |= PL_FLAG_BORN;
1499                 if (td2->td_dbgflags & TDB_EXIT)
1500                         pl->pl_flags |= PL_FLAG_EXITED;
1501                 pl->pl_sigmask = td2->td_sigmask;
1502                 pl->pl_siglist = td2->td_siglist;
1503                 strcpy(pl->pl_tdname, td2->td_name);
1504                 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) != 0) {
1505                         pl->pl_syscall_code = td2->td_sa.code;
1506                         pl->pl_syscall_narg = td2->td_sa.callp->sy_narg;
1507                 } else {
1508                         pl->pl_syscall_code = 0;
1509                         pl->pl_syscall_narg = 0;
1510                 }
1511                 CTR6(KTR_PTRACE,
1512     "PT_LWPINFO: tid %d (pid %d) event %d flags %#x child pid %d syscall %d",
1513                     td2->td_tid, p->p_pid, pl->pl_event, pl->pl_flags,
1514                     pl->pl_child_pid, pl->pl_syscall_code);
1515                 break;
1516
1517         case PT_GETNUMLWPS:
1518                 CTR2(KTR_PTRACE, "PT_GETNUMLWPS: pid %d: %d threads", p->p_pid,
1519                     p->p_numthreads);
1520                 td->td_retval[0] = p->p_numthreads;
1521                 break;
1522
1523         case PT_GETLWPLIST:
1524                 CTR3(KTR_PTRACE, "PT_GETLWPLIST: pid %d: data %d, actual %d",
1525                     p->p_pid, data, p->p_numthreads);
1526                 if (data <= 0) {
1527                         error = EINVAL;
1528                         break;
1529                 }
1530                 num = imin(p->p_numthreads, data);
1531                 PROC_UNLOCK(p);
1532                 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
1533                 tmp = 0;
1534                 PROC_LOCK(p);
1535                 FOREACH_THREAD_IN_PROC(p, td2) {
1536                         if (tmp >= num)
1537                                 break;
1538                         buf[tmp++] = td2->td_tid;
1539                 }
1540                 PROC_UNLOCK(p);
1541                 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
1542                 free(buf, M_TEMP);
1543                 if (!error)
1544                         td->td_retval[0] = tmp;
1545                 PROC_LOCK(p);
1546                 break;
1547
1548         case PT_VM_TIMESTAMP:
1549                 CTR2(KTR_PTRACE, "PT_VM_TIMESTAMP: pid %d: timestamp %d",
1550                     p->p_pid, p->p_vmspace->vm_map.timestamp);
1551                 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
1552                 break;
1553
1554         case PT_VM_ENTRY:
1555                 PROC_UNLOCK(p);
1556                 error = ptrace_vm_entry(td, p, addr);
1557                 PROC_LOCK(p);
1558                 break;
1559
1560         case PT_COREDUMP:
1561                 pc = addr;
1562                 CTR2(KTR_PTRACE, "PT_COREDUMP: pid %d, fd %d",
1563                     p->p_pid, pc->pc_fd);
1564
1565                 if ((pc->pc_flags & ~(PC_COMPRESS | PC_ALL)) != 0) {
1566                         error = EINVAL;
1567                         break;
1568                 }
1569                 PROC_UNLOCK(p);
1570
1571                 tcq = malloc(sizeof(*tcq), M_TEMP, M_WAITOK | M_ZERO);
1572                 fp = NULL;
1573                 error = fget_write(td, pc->pc_fd, &cap_write_rights, &fp);
1574                 if (error != 0)
1575                         goto coredump_cleanup_nofp;
1576                 if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VREG) {
1577                         error = EPIPE;
1578                         goto coredump_cleanup;
1579                 }
1580
1581                 PROC_LOCK(p);
1582                 error = proc_can_ptrace(td, p);
1583                 if (error != 0)
1584                         goto coredump_cleanup_locked;
1585
1586                 td2 = ptrace_sel_coredump_thread(p);
1587                 if (td2 == NULL) {
1588                         error = EBUSY;
1589                         goto coredump_cleanup_locked;
1590                 }
1591                 KASSERT((td2->td_dbgflags & (TDB_COREDUMPREQ |
1592                     TDB_SCREMOTEREQ)) == 0,
1593                     ("proc %d tid %d req coredump", p->p_pid, td2->td_tid));
1594
1595                 tcq->tc_vp = fp->f_vnode;
1596                 tcq->tc_limit = pc->pc_limit == 0 ? OFF_MAX : pc->pc_limit;
1597                 tcq->tc_flags = SVC_PT_COREDUMP;
1598                 if ((pc->pc_flags & PC_COMPRESS) == 0)
1599                         tcq->tc_flags |= SVC_NOCOMPRESS;
1600                 if ((pc->pc_flags & PC_ALL) != 0)
1601                         tcq->tc_flags |= SVC_ALL;
1602                 td2->td_remotereq = tcq;
1603                 td2->td_dbgflags |= TDB_COREDUMPREQ;
1604                 thread_run_flash(td2);
1605                 while ((td2->td_dbgflags & TDB_COREDUMPREQ) != 0)
1606                         msleep(p, &p->p_mtx, PPAUSE, "crdmp", 0);
1607                 error = tcq->tc_error;
1608 coredump_cleanup_locked:
1609                 PROC_UNLOCK(p);
1610 coredump_cleanup:
1611                 fdrop(fp, td);
1612 coredump_cleanup_nofp:
1613                 free(tcq, M_TEMP);
1614                 PROC_LOCK(p);
1615                 break;
1616
1617         case PT_SC_REMOTE:
1618                 pscr = addr;
1619                 CTR2(KTR_PTRACE, "PT_SC_REMOTE: pid %d, syscall %d",
1620                     p->p_pid, pscr->pscr_syscall);
1621                 if ((td2->td_dbgflags & TDB_BOUNDARY) == 0) {
1622                         error = EBUSY;
1623                         break;
1624                 }
1625                 PROC_UNLOCK(p);
1626                 MPASS(pscr->pscr_nargs <= nitems(td->td_sa.args));
1627
1628                 tsr = malloc(sizeof(struct thr_syscall_req), M_TEMP,
1629                     M_WAITOK | M_ZERO);
1630
1631                 tsr->ts_sa.code = pscr->pscr_syscall;
1632                 tsr->ts_nargs = pscr->pscr_nargs;
1633                 memcpy(&tsr->ts_sa.args, pscr->pscr_args,
1634                     sizeof(register_t) * tsr->ts_nargs);
1635
1636                 PROC_LOCK(p);
1637                 error = proc_can_ptrace(td, p);
1638                 if (error != 0) {
1639                         free(tsr, M_TEMP);
1640                         break;
1641                 }
1642                 if (td2->td_proc != p) {
1643                         free(tsr, M_TEMP);
1644                         error = ESRCH;
1645                         break;
1646                 }
1647                 KASSERT((td2->td_dbgflags & (TDB_COREDUMPREQ |
1648                     TDB_SCREMOTEREQ)) == 0,
1649                     ("proc %d tid %d req coredump", p->p_pid, td2->td_tid));
1650
1651                 td2->td_remotereq = tsr;
1652                 td2->td_dbgflags |= TDB_SCREMOTEREQ;
1653                 thread_run_flash(td2);
1654                 while ((td2->td_dbgflags & TDB_SCREMOTEREQ) != 0)
1655                         msleep(p, &p->p_mtx, PPAUSE, "pscrx", 0);
1656                 error = 0;
1657                 memcpy(&pscr->pscr_ret, &tsr->ts_ret, sizeof(tsr->ts_ret));
1658                 free(tsr, M_TEMP);
1659                 break;
1660
1661         default:
1662 #ifdef __HAVE_PTRACE_MACHDEP
1663                 if (req >= PT_FIRSTMACH) {
1664                         PROC_UNLOCK(p);
1665                         error = cpu_ptrace(td2, req, addr, data);
1666                         PROC_LOCK(p);
1667                 } else
1668 #endif
1669                         /* Unknown request. */
1670                         error = EINVAL;
1671                 break;
1672         }
1673 out:
1674         /* Drop our hold on this process now that the request has completed. */
1675         _PRELE(p);
1676 fail:
1677         if (p2_req_set) {
1678                 if ((p->p_flag2 & P2_PTRACEREQ) != 0)
1679                         wakeup(&p->p_flag2);
1680                 p->p_flag2 &= ~P2_PTRACEREQ;
1681         }
1682         PROC_UNLOCK(p);
1683         if (proctree_locked)
1684                 sx_xunlock(&proctree_lock);
1685         return (error);
1686 }
1687 #undef PROC_READ
1688 #undef PROC_WRITE