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/systm.h> 35 #include <sys/caprights.h> 36 #include <sys/filedesc.h> 37 #include <sys/imgact.h> 38 #include <sys/ktr.h> 39 #include <sys/limits.h> 40 #include <sys/lock.h> 41 #include <sys/malloc.h> 42 #include <sys/mman.h> 43 #include <sys/mutex.h> 44 #include <sys/priv.h> 45 #include <sys/proc.h> 46 #include <sys/ptrace.h> 47 #include <sys/reg.h> 48 #include <sys/rwlock.h> 49 #include <sys/signalvar.h> 50 #include <sys/sleepqueue.h> 51 #include <sys/sx.h> 52 #include <sys/syscallsubr.h> 53 #include <sys/sysent.h> 54 #include <sys/sysproto.h> 55 #include <sys/vnode.h> 56 57 #include <security/audit/audit.h> 58 59 #include <vm/vm.h> 60 #include <vm/pmap.h> 61 #include <vm/vm_extern.h> 62 #include <vm/vm_map.h> 63 #include <vm/vm_kern.h> 64 #include <vm/vm_object.h> 65 #include <vm/vm_page.h> 66 #include <vm/vm_param.h> 67 68 #ifdef COMPAT_FREEBSD32 69 #include <sys/procfs.h> 70 #endif 71 72 /* Assert it's safe to unlock a process, e.g. to allocate working memory */ 73 #define PROC_ASSERT_TRACEREQ(p) MPASS(((p)->p_flag2 & P2_PTRACEREQ) != 0) 74 75 /* 76 * Functions implemented below: 77 * 78 * proc_read_regs(proc, regs) 79 * Get the current user-visible register set from the process 80 * and copy it into the regs structure (<machine/reg.h>). 81 * The process is stopped at the time read_regs is called. 82 * 83 * proc_write_regs(proc, regs) 84 * Update the current register set from the passed in regs 85 * structure. Take care to avoid clobbering special CPU 86 * registers or privileged bits in the PSL. 87 * Depending on the architecture this may have fix-up work to do, 88 * especially if the IAR or PCW are modified. 89 * The process is stopped at the time write_regs is called. 90 * 91 * proc_read_fpregs, proc_write_fpregs 92 * deal with the floating point register set, otherwise as above. 93 * 94 * proc_read_dbregs, proc_write_dbregs 95 * deal with the processor debug register set, otherwise as above. 96 * 97 * proc_sstep(proc) 98 * Arrange for the process to trap after executing a single instruction. 99 */ 100 101 int 102 proc_read_regs(struct thread *td, struct reg *regs) 103 { 104 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 105 return (fill_regs(td, regs)); 106 } 107 108 int 109 proc_write_regs(struct thread *td, struct reg *regs) 110 { 111 int error; 112 113 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 114 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 115 if (error != 0) 116 return (error); 117 return (set_regs(td, regs)); 118 } 119 120 int 121 proc_read_dbregs(struct thread *td, struct dbreg *dbregs) 122 { 123 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 124 return (fill_dbregs(td, dbregs)); 125 } 126 127 int 128 proc_write_dbregs(struct thread *td, struct dbreg *dbregs) 129 { 130 int error; 131 132 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 133 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 134 if (error != 0) 135 return (error); 136 return (set_dbregs(td, dbregs)); 137 } 138 139 /* 140 * Ptrace doesn't support fpregs at all, and there are no security holes 141 * or translations for fpregs, so we can just copy them. 142 */ 143 int 144 proc_read_fpregs(struct thread *td, struct fpreg *fpregs) 145 { 146 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 147 return (fill_fpregs(td, fpregs)); 148 } 149 150 int 151 proc_write_fpregs(struct thread *td, struct fpreg *fpregs) 152 { 153 int error; 154 155 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 156 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 157 if (error != 0) 158 return (error); 159 return (set_fpregs(td, fpregs)); 160 } 161 162 static struct regset * 163 proc_find_regset(struct thread *td, int note) 164 { 165 struct regset **regsetp, **regset_end, *regset; 166 struct sysentvec *sv; 167 168 sv = td->td_proc->p_sysent; 169 regsetp = sv->sv_regset_begin; 170 if (regsetp == NULL) 171 return (NULL); 172 regset_end = sv->sv_regset_end; 173 MPASS(regset_end != NULL); 174 for (; regsetp < regset_end; regsetp++) { 175 regset = *regsetp; 176 if (regset->note != note) 177 continue; 178 179 return (regset); 180 } 181 182 return (NULL); 183 } 184 185 static int 186 proc_read_regset(struct thread *td, int note, struct iovec *iov) 187 { 188 struct regset *regset; 189 struct proc *p; 190 void *buf; 191 size_t size; 192 int error; 193 194 regset = proc_find_regset(td, note); 195 if (regset == NULL) 196 return (EINVAL); 197 198 if (regset->get == NULL) 199 return (EINVAL); 200 201 size = regset->size; 202 /* 203 * The regset is dynamically sized, e.g. the size could change 204 * depending on the hardware, or may have a per-thread size. 205 */ 206 if (size == 0) { 207 if (!regset->get(regset, td, NULL, &size)) 208 return (EINVAL); 209 } 210 211 if (iov->iov_base == NULL) { 212 iov->iov_len = size; 213 if (iov->iov_len == 0) 214 return (EINVAL); 215 216 return (0); 217 } 218 219 /* The length is wrong, return an error */ 220 if (iov->iov_len != size) 221 return (EINVAL); 222 223 error = 0; 224 p = td->td_proc; 225 226 /* Drop the proc lock while allocating the temp buffer */ 227 PROC_ASSERT_TRACEREQ(p); 228 PROC_UNLOCK(p); 229 buf = malloc(size, M_TEMP, M_WAITOK); 230 PROC_LOCK(p); 231 232 if (!regset->get(regset, td, buf, &size)) { 233 error = EINVAL; 234 } else { 235 KASSERT(size == regset->size || regset->size == 0, 236 ("%s: Getter function changed the size", __func__)); 237 238 iov->iov_len = size; 239 PROC_UNLOCK(p); 240 error = copyout(buf, iov->iov_base, size); 241 PROC_LOCK(p); 242 } 243 244 free(buf, M_TEMP); 245 246 return (error); 247 } 248 249 static int 250 proc_write_regset(struct thread *td, int note, struct iovec *iov) 251 { 252 struct regset *regset; 253 struct proc *p; 254 void *buf; 255 size_t size; 256 int error; 257 258 regset = proc_find_regset(td, note); 259 if (regset == NULL) 260 return (EINVAL); 261 262 size = regset->size; 263 /* 264 * The regset is dynamically sized, e.g. the size could change 265 * depending on the hardware, or may have a per-thread size. 266 */ 267 if (size == 0) { 268 if (!regset->get(regset, td, NULL, &size)) 269 return (EINVAL); 270 } 271 272 /* The length is wrong, return an error */ 273 if (iov->iov_len != size) 274 return (EINVAL); 275 276 if (regset->set == NULL) 277 return (EINVAL); 278 279 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 280 if (error != 0) 281 return (error); 282 283 p = td->td_proc; 284 285 /* Drop the proc lock while allocating the temp buffer */ 286 PROC_ASSERT_TRACEREQ(p); 287 PROC_UNLOCK(p); 288 buf = malloc(size, M_TEMP, M_WAITOK); 289 error = copyin(iov->iov_base, buf, size); 290 PROC_LOCK(p); 291 292 if (error == 0) { 293 if (!regset->set(regset, td, buf, size)) { 294 error = EINVAL; 295 } 296 } 297 298 free(buf, M_TEMP); 299 300 return (error); 301 } 302 303 #ifdef COMPAT_FREEBSD32 304 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 305 int 306 proc_read_regs32(struct thread *td, struct reg32 *regs32) 307 { 308 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 309 return (fill_regs32(td, regs32)); 310 } 311 312 int 313 proc_write_regs32(struct thread *td, struct reg32 *regs32) 314 { 315 int error; 316 317 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 318 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 319 if (error != 0) 320 return (error); 321 return (set_regs32(td, regs32)); 322 } 323 324 int 325 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 326 { 327 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 328 return (fill_dbregs32(td, dbregs32)); 329 } 330 331 int 332 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 333 { 334 int error; 335 336 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 337 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 338 if (error != 0) 339 return (error); 340 return (set_dbregs32(td, dbregs32)); 341 } 342 343 int 344 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 345 { 346 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 347 return (fill_fpregs32(td, fpregs32)); 348 } 349 350 int 351 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 352 { 353 int error; 354 355 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 356 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 357 if (error != 0) 358 return (error); 359 return (set_fpregs32(td, fpregs32)); 360 } 361 #endif 362 363 int 364 proc_sstep(struct thread *td) 365 { 366 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 367 return (ptrace_single_step(td)); 368 } 369 370 static int 371 proc_vmspace_check_access(struct thread *td, struct proc *p, int flags) 372 { 373 PROC_ASSERT_HELD(p); 374 if ((flags & PRVM_CHECK_DEBUG) != 0) 375 return (p_candebug(td, p)); 376 if ((flags & PRVM_CHECK_VISIBILITY) != 0) 377 return (p_cansee(td, p)); 378 return (0); 379 } 380 381 int 382 proc_vmspace_ref(struct thread *td, struct proc *p, int flags, 383 struct vmspace **vmp) 384 { 385 struct vmspace *vm; 386 int error; 387 388 MPASS((flags & ~(PRVM_BLOCK_EXEC | PRVM_CHECK_VISIBILITY | 389 PRVM_CHECK_DEBUG)) == 0); 390 MPASS((flags & (PRVM_CHECK_VISIBILITY | PRVM_CHECK_DEBUG)) != 391 (PRVM_CHECK_VISIBILITY | PRVM_CHECK_DEBUG)); 392 393 PROC_LOCK(p); 394 if (p != td->td_proc) { 395 PROC_ASSERT_HELD(p); 396 397 /* 398 * Make sure that the vmspace doesn't switch out from 399 * under us. 400 */ 401 if ((flags & PRVM_BLOCK_EXEC) != 0) { 402 for (;;) { 403 if (!execve_block(td, p)) { 404 PROC_LOCK(p); 405 continue; 406 } 407 error = proc_vmspace_check_access(td, p, flags); 408 if (error != 0) { 409 execve_unblock(td, p); 410 PROC_UNLOCK(p); 411 return (error); 412 } 413 break; 414 } 415 } else { 416 error = proc_vmspace_check_access(td, p, flags); 417 if (error != 0) { 418 PROC_UNLOCK(p); 419 return (error); 420 } 421 } 422 } 423 vm = vmspace_acquire_ref(p); 424 if (vm == NULL) { 425 if (p != td->td_proc && (flags & PRVM_BLOCK_EXEC) != 0) 426 execve_unblock(td, p); 427 PROC_UNLOCK(p); 428 return (ESRCH); 429 } 430 PROC_UNLOCK(p); 431 *vmp = vm; 432 return (0); 433 } 434 435 void 436 proc_vmspace_unref(struct thread *td, struct proc *p, int flags, 437 struct vmspace *vm) 438 { 439 vmspace_free(vm); 440 if (p != td->td_proc && (flags & PRVM_BLOCK_EXEC) != 0) { 441 PROC_LOCK(p); 442 PROC_ASSERT_HELD(p); 443 execve_unblock(td, p); 444 PROC_UNLOCK(p); 445 } 446 } 447 448 static int 449 vmspace_rwmem(struct vmspace *vm, struct uio *uio) 450 { 451 vm_map_t map; 452 vm_offset_t pageno; /* page number */ 453 vm_prot_t reqprot; 454 ssize_t orig_resid; 455 int error, fault_flags, page_offset, writing; 456 457 map = &vm->vm_map; 458 459 /* 460 * If we are writing, then we request vm_fault() to create a private 461 * copy of each page. Since these copies will not be writeable by the 462 * process, we must explicitly request that they be dirtied. 463 */ 464 writing = uio->uio_rw == UIO_WRITE; 465 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ; 466 fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 467 468 orig_resid = uio->uio_resid; 469 470 if (writing) { 471 error = priv_check(curthread, PRIV_PROC_MEM_WRITE); 472 if (error != 0) 473 return (error); 474 } 475 476 /* 477 * Only map in one page at a time. We don't have to, but it 478 * makes things easier. This way is trivial - right? 479 */ 480 do { 481 vm_offset_t uva; 482 u_int len; 483 vm_page_t m; 484 485 uva = (vm_offset_t)uio->uio_offset; 486 487 /* 488 * Get the page number of this segment. 489 */ 490 pageno = trunc_page(uva); 491 page_offset = uva - pageno; 492 493 /* 494 * How many bytes to copy 495 */ 496 len = MIN(PAGE_SIZE - page_offset, uio->uio_resid); 497 498 /* 499 * Fault and hold the page on behalf of the process. 500 */ 501 error = vm_fault(map, pageno, reqprot, fault_flags, &m); 502 if (error != KERN_SUCCESS) { 503 if (error == KERN_RESOURCE_SHORTAGE) 504 error = ENOMEM; 505 else 506 error = EFAULT; 507 break; 508 } 509 510 /* 511 * Now do the i/o move. 512 */ 513 error = uiomove_fromphys(&m, page_offset, len, uio); 514 515 /* Make the I-cache coherent for breakpoints. */ 516 if (writing && error == 0) { 517 vm_map_lock_read(map); 518 if (vm_map_check_protection(map, pageno, pageno + 519 PAGE_SIZE, VM_PROT_EXECUTE)) 520 vm_sync_icache(map, uva, len); 521 vm_map_unlock_read(map); 522 } 523 524 /* 525 * Release the page. 526 */ 527 vm_page_unwire(m, PQ_ACTIVE); 528 529 } while (error == 0 && uio->uio_resid > 0); 530 return (uio->uio_resid == orig_resid ? error : 0); 531 } 532 533 int 534 proc_rwmem(struct proc *p, struct uio *uio, int flags) 535 { 536 struct vmspace *vm; 537 struct thread *td; 538 int error; 539 540 td = curthread; 541 error = proc_vmspace_ref(td, p, flags, &vm); 542 if (error != 0) 543 return (error); 544 error = vmspace_rwmem(vm, uio); 545 proc_vmspace_unref(td, p, flags, vm); 546 return (error); 547 } 548 549 ssize_t 550 vmspace_iop(struct thread *td, struct vmspace *vm, vm_offset_t va, void *buf, 551 size_t len, enum uio_rw rw) 552 { 553 struct iovec iov; 554 struct uio uio; 555 ssize_t slen; 556 int error; 557 558 MPASS(len < SSIZE_MAX); 559 slen = (ssize_t)len; 560 561 iov.iov_base = (caddr_t)buf; 562 iov.iov_len = len; 563 uio.uio_iov = &iov; 564 uio.uio_iovcnt = 1; 565 uio.uio_offset = va; 566 uio.uio_resid = slen; 567 uio.uio_segflg = UIO_SYSSPACE; 568 uio.uio_rw = rw; 569 uio.uio_td = td; 570 error = vmspace_rwmem(vm, &uio); 571 if (error != 0 || uio.uio_resid == slen) 572 return (-1); 573 return (slen - uio.uio_resid); 574 } 575 576 ssize_t 577 proc_readmem(struct thread *td, struct proc *p, vm_offset_t va, void *buf, 578 size_t len) 579 { 580 581 return (vmspace_iop(td, p->p_vmspace, va, buf, len, UIO_READ)); 582 } 583 584 ssize_t 585 proc_writemem(struct thread *td, struct proc *p, vm_offset_t va, void *buf, 586 size_t len) 587 { 588 589 return (vmspace_iop(td, p->p_vmspace, va, buf, len, UIO_WRITE)); 590 } 591 592 static int 593 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve) 594 { 595 struct vattr vattr; 596 vm_map_t map; 597 vm_map_entry_t entry; 598 vm_object_t obj, tobj, lobj; 599 struct vmspace *vm; 600 struct vnode *vp; 601 char *freepath, *fullpath; 602 u_int pathlen; 603 int error, index; 604 605 error = 0; 606 obj = NULL; 607 608 vm = vmspace_acquire_ref(p); 609 map = &vm->vm_map; 610 vm_map_lock_read(map); 611 612 do { 613 KASSERT((map->header.eflags & MAP_ENTRY_IS_SUB_MAP) == 0, 614 ("Submap in map header")); 615 index = 0; 616 VM_MAP_ENTRY_FOREACH(entry, map) { 617 if (index >= pve->pve_entry && 618 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) 619 break; 620 index++; 621 } 622 if (index < pve->pve_entry) { 623 error = EINVAL; 624 break; 625 } 626 if (entry == &map->header) { 627 error = ENOENT; 628 break; 629 } 630 631 /* We got an entry. */ 632 pve->pve_entry = index + 1; 633 pve->pve_timestamp = map->timestamp; 634 pve->pve_start = entry->start; 635 pve->pve_end = entry->end - 1; 636 pve->pve_offset = entry->offset; 637 pve->pve_prot = entry->protection | 638 PROT_MAX(entry->max_protection); 639 640 /* Backing object's path needed? */ 641 if (pve->pve_pathlen == 0) 642 break; 643 644 pathlen = pve->pve_pathlen; 645 pve->pve_pathlen = 0; 646 647 obj = entry->object.vm_object; 648 if (obj != NULL) 649 VM_OBJECT_RLOCK(obj); 650 } while (0); 651 652 vm_map_unlock_read(map); 653 654 pve->pve_fsid = VNOVAL; 655 pve->pve_fileid = VNOVAL; 656 657 if (error == 0 && obj != NULL) { 658 lobj = obj; 659 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 660 if (tobj != obj) 661 VM_OBJECT_RLOCK(tobj); 662 if (lobj != obj) 663 VM_OBJECT_RUNLOCK(lobj); 664 lobj = tobj; 665 pve->pve_offset += tobj->backing_object_offset; 666 } 667 vp = vm_object_vnode(lobj); 668 if (vp != NULL) 669 vref(vp); 670 if (lobj != obj) 671 VM_OBJECT_RUNLOCK(lobj); 672 VM_OBJECT_RUNLOCK(obj); 673 674 if (vp != NULL) { 675 freepath = NULL; 676 fullpath = NULL; 677 vn_fullpath(vp, &fullpath, &freepath); 678 vn_lock(vp, LK_SHARED | LK_RETRY); 679 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) { 680 pve->pve_fileid = vattr.va_fileid; 681 pve->pve_fsid = vattr.va_fsid; 682 } 683 vput(vp); 684 685 if (fullpath != NULL) { 686 pve->pve_pathlen = strlen(fullpath) + 1; 687 if (pve->pve_pathlen <= pathlen) { 688 error = copyout(fullpath, pve->pve_path, 689 pve->pve_pathlen); 690 } else 691 error = ENAMETOOLONG; 692 } 693 if (freepath != NULL) 694 free(freepath, M_TEMP); 695 } 696 } 697 vmspace_free(vm); 698 if (error == 0) 699 CTR3(KTR_PTRACE, "PT_VM_ENTRY: pid %d, entry %d, start %p", 700 p->p_pid, pve->pve_entry, pve->pve_start); 701 702 return (error); 703 } 704 705 /* 706 * Process debugging system call. 707 */ 708 #ifndef _SYS_SYSPROTO_H_ 709 struct ptrace_args { 710 int req; 711 pid_t pid; 712 caddr_t addr; 713 int data; 714 }; 715 #endif 716 717 int 718 sys_ptrace(struct thread *td, struct ptrace_args *uap) 719 { 720 /* 721 * XXX this obfuscation is to reduce stack usage, but the register 722 * structs may be too large to put on the stack anyway. 723 */ 724 union { 725 struct ptrace_io_desc piod; 726 struct ptrace_lwpinfo pl; 727 struct ptrace_vm_entry pve; 728 struct ptrace_coredump pc; 729 struct ptrace_sc_remote sr; 730 struct dbreg dbreg; 731 struct fpreg fpreg; 732 struct reg reg; 733 struct iovec vec; 734 syscallarg_t args[nitems(td->td_sa.args)]; 735 struct ptrace_sc_ret psr; 736 int ptevents; 737 struct ptrace_child *children; 738 } r; 739 syscallarg_t pscr_args[nitems(td->td_sa.args)]; 740 void *addr; 741 int error; 742 743 if (!allow_ptrace) 744 return (ENOSYS); 745 error = 0; 746 747 AUDIT_ARG_PID(uap->pid); 748 AUDIT_ARG_CMD(uap->req); 749 AUDIT_ARG_VALUE(uap->data); 750 addr = &r; 751 switch (uap->req) { 752 case PT_GET_EVENT_MASK: 753 case PT_LWPINFO: 754 case PT_GET_SC_ARGS: 755 case PT_GET_SC_RET: 756 break; 757 case PT_SET_SC_RET: 758 if (uap->data != sizeof(r.psr)) 759 error = EINVAL; 760 else 761 error = copyin(uap->addr, &r.psr, sizeof(r.psr)); 762 break; 763 case PT_GETREGS: 764 bzero(&r.reg, sizeof(r.reg)); 765 break; 766 case PT_GETFPREGS: 767 bzero(&r.fpreg, sizeof(r.fpreg)); 768 break; 769 case PT_GETDBREGS: 770 bzero(&r.dbreg, sizeof(r.dbreg)); 771 break; 772 case PT_GETREGSET: 773 case PT_SETREGSET: 774 error = copyin(uap->addr, &r.vec, sizeof(r.vec)); 775 break; 776 case PT_SETREGS: 777 error = copyin(uap->addr, &r.reg, sizeof(r.reg)); 778 break; 779 case PT_SETFPREGS: 780 error = copyin(uap->addr, &r.fpreg, sizeof(r.fpreg)); 781 break; 782 case PT_SETDBREGS: 783 error = copyin(uap->addr, &r.dbreg, sizeof(r.dbreg)); 784 break; 785 case PT_SET_EVENT_MASK: 786 if (uap->data != sizeof(r.ptevents)) 787 error = EINVAL; 788 else 789 error = copyin(uap->addr, &r.ptevents, uap->data); 790 break; 791 case PT_IO: 792 error = copyin(uap->addr, &r.piod, sizeof(r.piod)); 793 break; 794 case PT_VM_ENTRY: 795 error = copyin(uap->addr, &r.pve, sizeof(r.pve)); 796 break; 797 case PT_COREDUMP: 798 if (uap->data != sizeof(r.pc)) 799 error = EINVAL; 800 else 801 error = copyin(uap->addr, &r.pc, uap->data); 802 break; 803 case PT_SC_REMOTE: 804 if (uap->data != sizeof(r.sr)) { 805 error = EINVAL; 806 break; 807 } 808 error = copyin(uap->addr, &r.sr, uap->data); 809 if (error != 0) 810 break; 811 if (r.sr.pscr_nargs > nitems(td->td_sa.args)) { 812 error = EINVAL; 813 break; 814 } 815 error = copyin(r.sr.pscr_args, pscr_args, 816 sizeof(u_long) * r.sr.pscr_nargs); 817 if (error != 0) 818 break; 819 r.sr.pscr_args = pscr_args; 820 break; 821 case PT_GET_CHILDREN: 822 if (uap->addr == NULL) 823 addr = NULL; 824 else if (uap->data < 0) 825 error = EINVAL; 826 else 827 addr = &r.children; 828 break; 829 case PTINTERNAL_FIRST ... PTINTERNAL_LAST: 830 error = EINVAL; 831 break; 832 default: 833 addr = uap->addr; 834 break; 835 } 836 if (error != 0) 837 return (error); 838 839 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 840 if (error != 0) 841 return (error); 842 843 switch (uap->req) { 844 case PT_VM_ENTRY: 845 error = copyout(&r.pve, uap->addr, sizeof(r.pve)); 846 break; 847 case PT_IO: 848 error = copyout(&r.piod, uap->addr, sizeof(r.piod)); 849 break; 850 case PT_GETREGS: 851 error = copyout(&r.reg, uap->addr, sizeof(r.reg)); 852 break; 853 case PT_GETFPREGS: 854 error = copyout(&r.fpreg, uap->addr, sizeof(r.fpreg)); 855 break; 856 case PT_GETDBREGS: 857 error = copyout(&r.dbreg, uap->addr, sizeof(r.dbreg)); 858 break; 859 case PT_GETREGSET: 860 error = copyout(&r.vec, uap->addr, sizeof(r.vec)); 861 break; 862 case PT_GET_EVENT_MASK: 863 /* NB: The size in uap->data is validated in kern_ptrace(). */ 864 error = copyout(&r.ptevents, uap->addr, uap->data); 865 break; 866 case PT_LWPINFO: 867 /* NB: The size in uap->data is validated in kern_ptrace(). */ 868 error = copyout(&r.pl, uap->addr, uap->data); 869 break; 870 case PT_GET_SC_ARGS: 871 error = copyout(r.args, uap->addr, MIN(uap->data, 872 sizeof(r.args))); 873 break; 874 case PT_GET_SC_RET: 875 error = copyout(&r.psr, uap->addr, MIN(uap->data, 876 sizeof(r.psr))); 877 break; 878 case PT_SC_REMOTE: 879 error = copyout(&r.sr.pscr_ret, uap->addr + 880 offsetof(struct ptrace_sc_remote, pscr_ret), 881 sizeof(r.sr.pscr_ret)); 882 break; 883 case PT_GET_CHILDREN: 884 if (uap->addr != NULL) { 885 error = copyout(r.children, uap->addr, 886 td->td_retval[0] * sizeof(struct ptrace_child)); 887 free(r.children, M_TEMP); 888 } 889 break; 890 } 891 892 return (error); 893 } 894 895 #ifdef COMPAT_FREEBSD32 896 /* 897 * PROC_READ(regs, td2, addr); 898 * becomes either: 899 * proc_read_regs(td2, addr); 900 * or 901 * proc_read_regs32(td2, addr); 902 * .. except this is done at runtime. There is an additional 903 * complication in that PROC_WRITE disallows 32 bit consumers 904 * from writing to 64 bit address space targets. 905 */ 906 #define PROC_READ(w, t, a) wrap32 ? \ 907 proc_read_ ## w ## 32(t, a) : \ 908 proc_read_ ## w (t, a) 909 #define PROC_WRITE(w, t, a) wrap32 ? \ 910 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 911 proc_write_ ## w (t, a) 912 #else 913 #define PROC_READ(w, t, a) proc_read_ ## w (t, a) 914 #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 915 #endif 916 917 void 918 proc_set_traced(struct proc *p, bool stop) 919 { 920 921 sx_assert(&proctree_lock, SX_XLOCKED); 922 PROC_LOCK_ASSERT(p, MA_OWNED); 923 p->p_flag |= P_TRACED; 924 if (stop) 925 p->p_flag2 |= P2_PTRACE_FSTP; 926 p->p_ptevents = PTRACE_DEFAULT; 927 } 928 929 void 930 ptrace_unsuspend(struct proc *p) 931 { 932 PROC_LOCK_ASSERT(p, MA_OWNED); 933 934 PROC_SLOCK(p); 935 p->p_flag &= ~(P_STOPPED_TRACE | P_STOPPED_SIG | P_WAITED); 936 thread_unsuspend(p); 937 PROC_SUNLOCK(p); 938 itimer_proc_continue(p); 939 kqtimer_proc_continue(p); 940 } 941 942 static int 943 proc_can_ptrace1(struct thread *td, struct proc *p) 944 { 945 int error; 946 947 PROC_LOCK_ASSERT(p, MA_OWNED); 948 949 if ((p->p_flag & P_WEXIT) != 0) 950 return (ESRCH); 951 if ((error = p_cansee(td, p)) != 0) 952 return (error); 953 if ((error = p_candebug(td, p)) != 0) 954 return (error); 955 return (0); 956 } 957 958 static int 959 proc_can_ptrace(struct thread *td, struct proc *p) 960 { 961 int error; 962 963 PROC_LOCK_ASSERT(p, MA_OWNED); 964 965 if ((error = proc_can_ptrace1(td, p)) != 0) 966 return (error); 967 968 /* not being traced... */ 969 if ((p->p_flag & P_TRACED) == 0) 970 return (EPERM); 971 972 /* not being traced by YOU */ 973 if (p->p_pptr != td->td_proc) 974 return (EBUSY); 975 976 /* not currently stopped */ 977 if ((p->p_flag & P_STOPPED_TRACE) == 0 || 978 p->p_suspcount != p->p_numthreads || 979 (p->p_flag & P_WAITED) == 0) 980 return (EBUSY); 981 982 return (0); 983 } 984 985 static int 986 ptrace_count_children(struct thread *td, struct proc *p, bool count_everything) 987 { 988 struct proc *pp; 989 int error, num; 990 991 sx_assert(&proctree_lock, SX_LOCKED); 992 num = 0; 993 LIST_FOREACH(pp, &p->p_children, p_sibling) { 994 if (count_everything) { 995 error = 0; 996 } else { 997 PROC_LOCK(pp); 998 error = p_cansee(td, pp); 999 PROC_UNLOCK(pp); 1000 } 1001 if (error != 0) 1002 continue; 1003 num++; 1004 } 1005 LIST_FOREACH(pp, &p->p_orphans, p_orphan) { 1006 if (count_everything) { 1007 error = 0; 1008 } else { 1009 PROC_LOCK(pp); 1010 error = p_cansee(td, pp); 1011 PROC_UNLOCK(pp); 1012 } 1013 if (error != 0) 1014 continue; 1015 num++; 1016 } 1017 return (num); 1018 } 1019 1020 static bool 1021 ptrace_report_child(struct thread *td, struct proc *p, struct proc *pp, 1022 struct ptrace_child *ptc) 1023 { 1024 sx_assert(&proctree_lock, SX_LOCKED); 1025 1026 PROC_LOCK(pp); 1027 if (p_cansee(td, pp) != 0) { 1028 PROC_UNLOCK(pp); 1029 return (false); 1030 } 1031 ptc->pid = pp->p_pid; 1032 if ((pp->p_flag & P_TRACED) != 0) { 1033 ptc->flags |= PTCHLD_TRACED; 1034 if (pp->p_pptr == td->td_proc) 1035 ptc->flags |= PTCHLD_TRACED_BY_ME; 1036 } 1037 if ((pp->p_flag & P_WEXIT) != 0) 1038 ptc->flags |= PTCHLD_EXITED; 1039 PROC_UNLOCK(pp); 1040 return (true); 1041 } 1042 1043 static struct thread * 1044 ptrace_sel_coredump_thread(struct proc *p) 1045 { 1046 struct thread *td2; 1047 1048 PROC_LOCK_ASSERT(p, MA_OWNED); 1049 MPASS((p->p_flag & P_STOPPED_TRACE) != 0); 1050 1051 FOREACH_THREAD_IN_PROC(p, td2) { 1052 if ((td2->td_dbgflags & TDB_SSWITCH) != 0) 1053 return (td2); 1054 } 1055 return (NULL); 1056 } 1057 1058 int 1059 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 1060 { 1061 struct iovec iov; 1062 struct uio uio; 1063 struct proc *curp, *p, *pp; 1064 struct thread *td2 = NULL, *td3; 1065 struct ptrace_io_desc *piod = NULL; 1066 struct ptrace_lwpinfo *pl; 1067 struct ptrace_sc_ret *psr; 1068 struct ptrace_sc_remote *pscr; 1069 struct file *fp; 1070 struct ptrace_coredump *pc; 1071 struct thr_coredump_req *tcq; 1072 struct thr_syscall_req *tsr; 1073 struct ptrace_child *children, *ptc; 1074 int error, num, num1, tmp; 1075 lwpid_t tid = 0, *buf; 1076 #ifdef COMPAT_FREEBSD32 1077 int wrap32 = 0, safe = 0; 1078 #endif 1079 bool need_can_ptrace, proctree_locked, p2_req_set; 1080 1081 curp = td->td_proc; 1082 proctree_locked = false; 1083 p2_req_set = false; 1084 1085 /* Lock proctree before locking the process. */ 1086 switch (req) { 1087 case PT_TRACE_ME: 1088 case PT_ATTACH: 1089 case PT_STEP: 1090 case PT_CONTINUE: 1091 case PT_TO_SCE: 1092 case PT_TO_SCX: 1093 case PT_SYSCALL: 1094 case PT_FOLLOW_FORK: 1095 case PT_LWP_EVENTS: 1096 case PT_GET_EVENT_MASK: 1097 case PT_SET_EVENT_MASK: 1098 case PT_DETACH: 1099 case PT_GET_SC_ARGS: 1100 case PT_GET_CHILDREN: 1101 sx_xlock(&proctree_lock); 1102 proctree_locked = true; 1103 break; 1104 default: 1105 break; 1106 } 1107 1108 if (req == PT_TRACE_ME) { 1109 p = td->td_proc; 1110 PROC_LOCK(p); 1111 } else { 1112 if (pid <= PID_MAX) { 1113 if ((p = pfind(pid)) == NULL) { 1114 if (proctree_locked) 1115 sx_xunlock(&proctree_lock); 1116 return (ESRCH); 1117 } 1118 } else { 1119 td2 = tdfind(pid, -1); 1120 if (td2 == NULL) { 1121 if (proctree_locked) 1122 sx_xunlock(&proctree_lock); 1123 return (ESRCH); 1124 } 1125 p = td2->td_proc; 1126 tid = pid; 1127 pid = p->p_pid; 1128 } 1129 } 1130 AUDIT_ARG_PROCESS(p); 1131 1132 error = proc_can_ptrace1(td, p); 1133 if (error != 0) 1134 goto fail; 1135 1136 /* 1137 * System processes can't be debugged. 1138 */ 1139 if ((p->p_flag & P_SYSTEM) != 0) { 1140 error = EINVAL; 1141 goto fail; 1142 } 1143 1144 if (tid == 0) { 1145 if ((p->p_flag & P_STOPPED_TRACE) != 0) 1146 td2 = p->p_xthread; 1147 if (td2 == NULL) 1148 td2 = FIRST_THREAD_IN_PROC(p); 1149 tid = td2->td_tid; 1150 } 1151 1152 #ifdef COMPAT_FREEBSD32 1153 /* 1154 * Test if we're a 32 bit client and what the target is. 1155 * Set the wrap controls accordingly. 1156 */ 1157 if (SV_CURPROC_FLAG(SV_ILP32)) { 1158 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32)) 1159 safe = 1; 1160 wrap32 = 1; 1161 } 1162 #endif 1163 /* 1164 * Permissions check 1165 */ 1166 need_can_ptrace = true; 1167 switch (req) { 1168 case PT_TRACE_ME: 1169 /* 1170 * Always legal, when there is a parent process which 1171 * could trace us. Otherwise, reject. 1172 */ 1173 if ((p->p_flag & P_TRACED) != 0) { 1174 error = EBUSY; 1175 goto fail; 1176 } 1177 if (p->p_pptr == initproc) { 1178 error = EPERM; 1179 goto fail; 1180 } 1181 break; 1182 1183 case PT_ATTACH: 1184 /* Self */ 1185 if (p == td->td_proc) { 1186 error = EINVAL; 1187 goto fail; 1188 } 1189 1190 /* Already traced */ 1191 if (p->p_flag & P_TRACED) { 1192 error = EBUSY; 1193 goto fail; 1194 } 1195 1196 /* Can't trace an ancestor if you're being traced. */ 1197 if (curp->p_flag & P_TRACED) { 1198 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 1199 if (pp == p) { 1200 error = EINVAL; 1201 goto fail; 1202 } 1203 } 1204 } 1205 1206 /* OK */ 1207 break; 1208 1209 default: 1210 /* 1211 * Allow thread to clear single step for itself. 1212 * PT_GET_CHILDREN on itself does not need P_TRACED. 1213 */ 1214 if ((req == PT_CLEARSTEP && td->td_tid == tid) || 1215 (req == PT_GET_CHILDREN && p == curp)) 1216 need_can_ptrace = false; 1217 1218 /* 1219 * Check for ptrace eligibility before waiting for 1220 * holds to drain. 1221 */ 1222 if (need_can_ptrace) { 1223 error = proc_can_ptrace(td, p); 1224 if (error != 0) 1225 goto fail; 1226 } 1227 1228 /* 1229 * Block parallel ptrace requests. Most important, do 1230 * not allow other thread in debugger to continue the 1231 * debuggee until coredump finished. 1232 */ 1233 while ((p->p_flag2 & P2_PTRACEREQ) != 0) { 1234 if (proctree_locked) 1235 sx_xunlock(&proctree_lock); 1236 error = msleep(&p->p_flag2, &p->p_mtx, PPAUSE | PCATCH | 1237 (proctree_locked ? PDROP : 0), "pptrace", 0); 1238 if (proctree_locked) { 1239 sx_xlock(&proctree_lock); 1240 PROC_LOCK(p); 1241 } 1242 if (error == 0 && td2->td_proc != p) 1243 error = ESRCH; 1244 if (error == 0 && need_can_ptrace) 1245 error = proc_can_ptrace(td, p); 1246 if (error != 0) 1247 goto fail; 1248 } 1249 1250 /* Ok */ 1251 break; 1252 } 1253 1254 /* 1255 * Keep this process around and request parallel ptrace() 1256 * request to wait until we finish this request. 1257 */ 1258 MPASS((p->p_flag2 & P2_PTRACEREQ) == 0); 1259 p->p_flag2 |= P2_PTRACEREQ; 1260 p2_req_set = true; 1261 _PHOLD(p); 1262 1263 /* 1264 * Actually do the requests 1265 */ 1266 1267 td->td_retval[0] = 0; 1268 1269 switch (req) { 1270 case PT_TRACE_ME: 1271 /* set my trace flag and "owner" so it can read/write me */ 1272 proc_set_traced(p, false); 1273 if (p->p_flag & P_PPWAIT) 1274 p->p_flag |= P_PPTRACE; 1275 CTR1(KTR_PTRACE, "PT_TRACE_ME: pid %d", p->p_pid); 1276 break; 1277 1278 case PT_ATTACH: 1279 /* security check done above */ 1280 /* 1281 * It would be nice if the tracing relationship was separate 1282 * from the parent relationship but that would require 1283 * another set of links in the proc struct or for "wait" 1284 * to scan the entire proc table. To make life easier, 1285 * we just re-parent the process we're trying to trace. 1286 * The old parent is remembered so we can put things back 1287 * on a "detach". 1288 */ 1289 proc_set_traced(p, true); 1290 proc_reparent(p, td->td_proc, false); 1291 CTR2(KTR_PTRACE, "PT_ATTACH: pid %d, oppid %d", p->p_pid, 1292 p->p_oppid); 1293 1294 sx_xunlock(&proctree_lock); 1295 proctree_locked = false; 1296 MPASS(p->p_xthread == NULL); 1297 MPASS((p->p_flag & P_STOPPED_TRACE) == 0); 1298 1299 /* 1300 * If already stopped due to a stop signal, clear the 1301 * existing stop before triggering a traced SIGSTOP. 1302 */ 1303 if ((p->p_flag & P_STOPPED_SIG) != 0) { 1304 PROC_SLOCK(p); 1305 p->p_flag &= ~(P_STOPPED_SIG | P_WAITED); 1306 thread_unsuspend(p); 1307 PROC_SUNLOCK(p); 1308 } 1309 1310 kern_psignal(p, SIGSTOP); 1311 break; 1312 1313 case PT_CLEARSTEP: 1314 CTR2(KTR_PTRACE, "PT_CLEARSTEP: tid %d (pid %d)", td2->td_tid, 1315 p->p_pid); 1316 error = ptrace_clear_single_step(td2); 1317 break; 1318 1319 case PT_SETSTEP: 1320 CTR2(KTR_PTRACE, "PT_SETSTEP: tid %d (pid %d)", td2->td_tid, 1321 p->p_pid); 1322 error = ptrace_single_step(td2); 1323 break; 1324 1325 case PT_SUSPEND: 1326 CTR2(KTR_PTRACE, "PT_SUSPEND: tid %d (pid %d)", td2->td_tid, 1327 p->p_pid); 1328 td2->td_dbgflags |= TDB_SUSPEND; 1329 ast_sched(td2, TDA_SUSPEND); 1330 break; 1331 1332 case PT_RESUME: 1333 CTR2(KTR_PTRACE, "PT_RESUME: tid %d (pid %d)", td2->td_tid, 1334 p->p_pid); 1335 td2->td_dbgflags &= ~TDB_SUSPEND; 1336 break; 1337 1338 case PT_FOLLOW_FORK: 1339 CTR3(KTR_PTRACE, "PT_FOLLOW_FORK: pid %d %s -> %s", p->p_pid, 1340 p->p_ptevents & PTRACE_FORK ? "enabled" : "disabled", 1341 data ? "enabled" : "disabled"); 1342 if (data) 1343 p->p_ptevents |= PTRACE_FORK; 1344 else 1345 p->p_ptevents &= ~PTRACE_FORK; 1346 break; 1347 1348 case PT_LWP_EVENTS: 1349 CTR3(KTR_PTRACE, "PT_LWP_EVENTS: pid %d %s -> %s", p->p_pid, 1350 p->p_ptevents & PTRACE_LWP ? "enabled" : "disabled", 1351 data ? "enabled" : "disabled"); 1352 if (data) 1353 p->p_ptevents |= PTRACE_LWP; 1354 else 1355 p->p_ptevents &= ~PTRACE_LWP; 1356 break; 1357 1358 case PT_GET_EVENT_MASK: 1359 if (data != sizeof(p->p_ptevents)) { 1360 error = EINVAL; 1361 break; 1362 } 1363 CTR2(KTR_PTRACE, "PT_GET_EVENT_MASK: pid %d mask %#x", p->p_pid, 1364 p->p_ptevents); 1365 *(int *)addr = p->p_ptevents; 1366 break; 1367 1368 case PT_SET_EVENT_MASK: 1369 if (data != sizeof(p->p_ptevents)) { 1370 error = EINVAL; 1371 break; 1372 } 1373 tmp = *(int *)addr; 1374 if ((tmp & ~(PTRACE_EXEC | PTRACE_SCE | PTRACE_SCX | 1375 PTRACE_FORK | PTRACE_LWP | PTRACE_VFORK)) != 0) { 1376 error = EINVAL; 1377 break; 1378 } 1379 CTR3(KTR_PTRACE, "PT_SET_EVENT_MASK: pid %d mask %#x -> %#x", 1380 p->p_pid, p->p_ptevents, tmp); 1381 p->p_ptevents = tmp; 1382 break; 1383 1384 case PT_GET_SC_ARGS: 1385 case PTLINUX_GET_SC_ARGS: 1386 CTR2(KTR_PTRACE, "%s: pid %d", req == PT_GET_SC_ARGS ? 1387 "PT_GET_SC_ARGS" : "PT_LINUX_GET_SC_ARGS", p->p_pid); 1388 if (((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) == 0 && 1389 td2->td_sa.code == 0) 1390 #ifdef COMPAT_FREEBSD32 1391 || (wrap32 && !safe) 1392 #endif 1393 ) { 1394 error = EINVAL; 1395 break; 1396 } 1397 if (req == PT_GET_SC_ARGS) { 1398 bzero(addr, sizeof(td2->td_sa.args)); 1399 bcopy(td2->td_sa.args, addr, td2->td_sa.callp->sy_narg * 1400 sizeof(syscallarg_t)); 1401 } else { 1402 /* 1403 * Emulate a Linux bug which which strace(1) depends on: 1404 * at initialization it tests whether ptrace works by 1405 * calling close(2), or some other single-argument 1406 * syscall, _with six arguments_, and then verifies 1407 * whether it can fetch them all using this API; 1408 * otherwise it bails out. 1409 */ 1410 bcopy(td2->td_sa.args, addr, 6 * sizeof(syscallarg_t)); 1411 } 1412 break; 1413 1414 case PT_GET_SC_RET: 1415 if ((td2->td_dbgflags & TDB_SCX) == 0 1416 #ifdef COMPAT_FREEBSD32 1417 || (wrap32 && !safe) 1418 #endif 1419 ) { 1420 error = EINVAL; 1421 break; 1422 } 1423 psr = addr; 1424 bzero(psr, sizeof(*psr)); 1425 psr->sr_error = td2->td_errno; 1426 if (psr->sr_error == 0) { 1427 psr->sr_retval[0] = td2->td_retval[0]; 1428 psr->sr_retval[1] = td2->td_retval[1]; 1429 } 1430 CTR4(KTR_PTRACE, 1431 "PT_GET_SC_RET: pid %d error %d retval %#lx,%#lx", 1432 p->p_pid, psr->sr_error, psr->sr_retval[0], 1433 psr->sr_retval[1]); 1434 break; 1435 1436 case PT_SET_SC_RET: 1437 if ((td2->td_dbgflags & TDB_SCE) == 0 1438 #ifdef COMPAT_FREEBSD32 1439 || (wrap32 && !safe) 1440 #endif 1441 ) { 1442 error = EINVAL; 1443 break; 1444 } 1445 psr = addr; 1446 td2->td_errno = psr->sr_error; 1447 if (td2->td_errno == 0) { 1448 td2->td_retval[0] = psr->sr_retval[0]; 1449 td2->td_retval[1] = psr->sr_retval[1]; 1450 } 1451 td2->td_dbgflags |= TDB_SET_SC_RET; 1452 break; 1453 1454 case PT_STEP: 1455 case PT_CONTINUE: 1456 case PT_TO_SCE: 1457 case PT_TO_SCX: 1458 case PT_SYSCALL: 1459 case PT_DETACH: 1460 /* Zero means do not send any signal */ 1461 if (data < 0 || data > _SIG_MAXSIG) { 1462 error = EINVAL; 1463 break; 1464 } 1465 1466 switch (req) { 1467 case PT_STEP: 1468 CTR3(KTR_PTRACE, "PT_STEP: tid %d (pid %d), sig = %d", 1469 td2->td_tid, p->p_pid, data); 1470 error = ptrace_single_step(td2); 1471 if (error != 0) 1472 goto out; 1473 break; 1474 case PT_CONTINUE: 1475 case PT_TO_SCE: 1476 case PT_TO_SCX: 1477 case PT_SYSCALL: 1478 if (addr != (void *)1) { 1479 error = ptrace_set_pc(td2, 1480 (u_long)(uintfptr_t)addr); 1481 if (error != 0) 1482 goto out; 1483 td2->td_dbgflags |= TDB_USERWR; 1484 } 1485 switch (req) { 1486 case PT_TO_SCE: 1487 p->p_ptevents |= PTRACE_SCE; 1488 CTR4(KTR_PTRACE, 1489 "PT_TO_SCE: pid %d, events = %#x, PC = %#lx, sig = %d", 1490 p->p_pid, p->p_ptevents, 1491 (u_long)(uintfptr_t)addr, data); 1492 break; 1493 case PT_TO_SCX: 1494 p->p_ptevents |= PTRACE_SCX; 1495 CTR4(KTR_PTRACE, 1496 "PT_TO_SCX: pid %d, events = %#x, PC = %#lx, sig = %d", 1497 p->p_pid, p->p_ptevents, 1498 (u_long)(uintfptr_t)addr, data); 1499 break; 1500 case PT_SYSCALL: 1501 p->p_ptevents |= PTRACE_SYSCALL; 1502 CTR4(KTR_PTRACE, 1503 "PT_SYSCALL: pid %d, events = %#x, PC = %#lx, sig = %d", 1504 p->p_pid, p->p_ptevents, 1505 (u_long)(uintfptr_t)addr, data); 1506 break; 1507 case PT_CONTINUE: 1508 CTR3(KTR_PTRACE, 1509 "PT_CONTINUE: pid %d, PC = %#lx, sig = %d", 1510 p->p_pid, (u_long)(uintfptr_t)addr, data); 1511 break; 1512 } 1513 break; 1514 case PT_DETACH: 1515 /* 1516 * Clear P_TRACED before reparenting 1517 * a detached process back to its original 1518 * parent. Otherwise the debugee will be set 1519 * as an orphan of the debugger. 1520 */ 1521 p->p_flag &= ~(P_TRACED | P_WAITED); 1522 1523 /* 1524 * Reset the process parent. 1525 */ 1526 if (p->p_oppid != p->p_pptr->p_pid) { 1527 PROC_LOCK(p->p_pptr); 1528 sigqueue_take(p->p_ksi); 1529 PROC_UNLOCK(p->p_pptr); 1530 1531 pp = proc_realparent(p); 1532 proc_reparent(p, pp, false); 1533 if (pp == initproc) 1534 p->p_sigparent = SIGCHLD; 1535 CTR3(KTR_PTRACE, 1536 "PT_DETACH: pid %d reparented to pid %d, sig %d", 1537 p->p_pid, pp->p_pid, data); 1538 } else { 1539 CTR2(KTR_PTRACE, "PT_DETACH: pid %d, sig %d", 1540 p->p_pid, data); 1541 } 1542 1543 p->p_ptevents = 0; 1544 FOREACH_THREAD_IN_PROC(p, td3) { 1545 if ((td3->td_dbgflags & TDB_FSTP) != 0) { 1546 sigqueue_delete(&td3->td_sigqueue, 1547 SIGSTOP); 1548 } 1549 td3->td_dbgflags &= ~(TDB_XSIG | TDB_FSTP | 1550 TDB_SUSPEND | TDB_BORN); 1551 } 1552 1553 if ((p->p_flag2 & P2_PTRACE_FSTP) != 0) { 1554 sigqueue_delete(&p->p_sigqueue, SIGSTOP); 1555 p->p_flag2 &= ~P2_PTRACE_FSTP; 1556 } 1557 1558 /* 1559 * Send SIGCHLD and wakeup the parent as needed. It 1560 * may be the case that they had stopped the child 1561 * before it got ptraced, and now they're in the middle 1562 * of a wait(2) for it to continue. 1563 */ 1564 PROC_LOCK(p->p_pptr); 1565 childproc_continued(p); 1566 PROC_UNLOCK(p->p_pptr); 1567 break; 1568 } 1569 1570 sx_xunlock(&proctree_lock); 1571 proctree_locked = false; 1572 1573 sendsig: 1574 MPASS(!proctree_locked); 1575 1576 /* 1577 * Clear the pending event for the thread that just 1578 * reported its event (p_xthread), if any. This may 1579 * not be the thread passed to PT_CONTINUE, PT_STEP, 1580 * etc. if the debugger is resuming a different 1581 * thread. There might be no reporting thread if 1582 * the process was just attached. 1583 * 1584 * Deliver any pending signal via the reporting thread. 1585 */ 1586 if (p->p_xthread != NULL) { 1587 p->p_xthread->td_dbgflags &= ~TDB_XSIG; 1588 p->p_xthread->td_xsig = data; 1589 p->p_xthread = NULL; 1590 } 1591 p->p_xsig = data; 1592 1593 /* 1594 * P_WKILLED is insurance that a PT_KILL/SIGKILL 1595 * always works immediately, even if another thread is 1596 * unsuspended first and attempts to handle a 1597 * different signal or if the POSIX.1b style signal 1598 * queue cannot accommodate any new signals. 1599 */ 1600 if (data == SIGKILL) 1601 proc_wkilled(p); 1602 1603 /* 1604 * If the PT_CONTINUE-like operation is attempted on 1605 * the thread on sleepq, this is possible only after 1606 * the transparent PT_ATTACH. In this case, if the 1607 * caller modified the thread state, e.g. by writing 1608 * register file or specifying the pc, make the thread 1609 * xstopped by waking it up. 1610 */ 1611 if ((td2->td_dbgflags & TDB_USERWR) != 0 && 1612 pt_attach_transparent) { 1613 thread_lock(td2); 1614 if (TD_ON_SLEEPQ(td2) && 1615 (td2->td_flags & TDF_SINTR) != 0) { 1616 td2->td_dbgflags &= ~TDB_USERWR; 1617 sleepq_abort(td2, EINTR); 1618 } else { 1619 thread_unlock(td2); 1620 } 1621 } 1622 1623 /* 1624 * Unsuspend all threads. To leave a thread 1625 * suspended, use PT_SUSPEND to suspend it before 1626 * continuing the process. 1627 */ 1628 ptrace_unsuspend(p); 1629 break; 1630 1631 case PT_WRITE_I: 1632 case PT_WRITE_D: 1633 td2->td_dbgflags |= TDB_USERWR; 1634 PROC_UNLOCK(p); 1635 error = 0; 1636 if (proc_writemem(td, p, (off_t)(uintptr_t)addr, &data, 1637 sizeof(int)) != sizeof(int)) 1638 error = ENOMEM; 1639 else 1640 CTR3(KTR_PTRACE, "PT_WRITE: pid %d: %p <= %#x", 1641 p->p_pid, addr, data); 1642 PROC_LOCK(p); 1643 break; 1644 1645 case PT_READ_I: 1646 case PT_READ_D: 1647 PROC_UNLOCK(p); 1648 error = tmp = 0; 1649 if (proc_readmem(td, p, (off_t)(uintptr_t)addr, &tmp, 1650 sizeof(int)) != sizeof(int)) 1651 error = ENOMEM; 1652 else 1653 CTR3(KTR_PTRACE, "PT_READ: pid %d: %p >= %#x", 1654 p->p_pid, addr, tmp); 1655 td->td_retval[0] = tmp; 1656 PROC_LOCK(p); 1657 break; 1658 1659 case PT_IO: 1660 piod = addr; 1661 if (piod->piod_len > SSIZE_MAX) { 1662 error = EINVAL; 1663 goto out; 1664 } 1665 iov.iov_base = piod->piod_addr; 1666 iov.iov_len = piod->piod_len; 1667 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 1668 uio.uio_resid = piod->piod_len; 1669 uio.uio_iov = &iov; 1670 uio.uio_iovcnt = 1; 1671 uio.uio_segflg = UIO_USERSPACE; 1672 uio.uio_td = td; 1673 switch (piod->piod_op) { 1674 case PIOD_READ_D: 1675 case PIOD_READ_I: 1676 CTR3(KTR_PTRACE, "PT_IO: pid %d: READ (%p, %#x)", 1677 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid); 1678 uio.uio_rw = UIO_READ; 1679 break; 1680 case PIOD_WRITE_D: 1681 case PIOD_WRITE_I: 1682 CTR3(KTR_PTRACE, "PT_IO: pid %d: WRITE (%p, %#x)", 1683 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid); 1684 td2->td_dbgflags |= TDB_USERWR; 1685 uio.uio_rw = UIO_WRITE; 1686 break; 1687 default: 1688 error = EINVAL; 1689 goto out; 1690 } 1691 PROC_UNLOCK(p); 1692 error = proc_rwmem(p, &uio, 0); 1693 piod->piod_len -= uio.uio_resid; 1694 PROC_LOCK(p); 1695 break; 1696 1697 case PT_KILL: 1698 CTR1(KTR_PTRACE, "PT_KILL: pid %d", p->p_pid); 1699 data = SIGKILL; 1700 goto sendsig; /* in PT_CONTINUE above */ 1701 1702 case PT_SETREGS: 1703 CTR2(KTR_PTRACE, "PT_SETREGS: tid %d (pid %d)", td2->td_tid, 1704 p->p_pid); 1705 td2->td_dbgflags |= TDB_USERWR; 1706 error = PROC_WRITE(regs, td2, addr); 1707 break; 1708 1709 case PT_GETREGS: 1710 CTR2(KTR_PTRACE, "PT_GETREGS: tid %d (pid %d)", td2->td_tid, 1711 p->p_pid); 1712 error = PROC_READ(regs, td2, addr); 1713 break; 1714 1715 case PT_SETFPREGS: 1716 CTR2(KTR_PTRACE, "PT_SETFPREGS: tid %d (pid %d)", td2->td_tid, 1717 p->p_pid); 1718 td2->td_dbgflags |= TDB_USERWR; 1719 error = PROC_WRITE(fpregs, td2, addr); 1720 break; 1721 1722 case PT_GETFPREGS: 1723 CTR2(KTR_PTRACE, "PT_GETFPREGS: tid %d (pid %d)", td2->td_tid, 1724 p->p_pid); 1725 error = PROC_READ(fpregs, td2, addr); 1726 break; 1727 1728 case PT_SETDBREGS: 1729 CTR2(KTR_PTRACE, "PT_SETDBREGS: tid %d (pid %d)", td2->td_tid, 1730 p->p_pid); 1731 td2->td_dbgflags |= TDB_USERWR; 1732 error = PROC_WRITE(dbregs, td2, addr); 1733 break; 1734 1735 case PT_GETDBREGS: 1736 CTR2(KTR_PTRACE, "PT_GETDBREGS: tid %d (pid %d)", td2->td_tid, 1737 p->p_pid); 1738 error = PROC_READ(dbregs, td2, addr); 1739 break; 1740 1741 case PT_SETREGSET: 1742 CTR2(KTR_PTRACE, "PT_SETREGSET: tid %d (pid %d)", td2->td_tid, 1743 p->p_pid); 1744 error = proc_write_regset(td2, data, addr); 1745 break; 1746 1747 case PT_GETREGSET: 1748 CTR2(KTR_PTRACE, "PT_GETREGSET: tid %d (pid %d)", td2->td_tid, 1749 p->p_pid); 1750 error = proc_read_regset(td2, data, addr); 1751 break; 1752 1753 case PT_LWPINFO: 1754 if (data <= 0 || data > sizeof(*pl)) { 1755 error = EINVAL; 1756 break; 1757 } 1758 pl = addr; 1759 bzero(pl, sizeof(*pl)); 1760 pl->pl_lwpid = td2->td_tid; 1761 pl->pl_event = PL_EVENT_NONE; 1762 pl->pl_flags = 0; 1763 if (td2->td_dbgflags & TDB_XSIG) { 1764 pl->pl_event = PL_EVENT_SIGNAL; 1765 if (td2->td_si.si_signo != 0 && 1766 data >= offsetof(struct ptrace_lwpinfo, pl_siginfo) 1767 + sizeof(pl->pl_siginfo)){ 1768 pl->pl_flags |= PL_FLAG_SI; 1769 pl->pl_siginfo = td2->td_si; 1770 } 1771 } 1772 if (td2->td_dbgflags & TDB_SCE) 1773 pl->pl_flags |= PL_FLAG_SCE; 1774 else if (td2->td_dbgflags & TDB_SCX) 1775 pl->pl_flags |= PL_FLAG_SCX; 1776 if (td2->td_dbgflags & TDB_EXEC) 1777 pl->pl_flags |= PL_FLAG_EXEC; 1778 if (td2->td_dbgflags & TDB_FORK) { 1779 pl->pl_flags |= PL_FLAG_FORKED; 1780 pl->pl_child_pid = td2->td_dbg_forked; 1781 if (td2->td_dbgflags & TDB_VFORK) 1782 pl->pl_flags |= PL_FLAG_VFORKED; 1783 } else if ((td2->td_dbgflags & (TDB_SCX | TDB_VFORK)) == 1784 TDB_VFORK) 1785 pl->pl_flags |= PL_FLAG_VFORK_DONE; 1786 if (td2->td_dbgflags & TDB_CHILD) 1787 pl->pl_flags |= PL_FLAG_CHILD; 1788 if (td2->td_dbgflags & TDB_BORN) 1789 pl->pl_flags |= PL_FLAG_BORN; 1790 if (td2->td_dbgflags & TDB_EXIT) 1791 pl->pl_flags |= PL_FLAG_EXITED; 1792 pl->pl_sigmask = td2->td_sigmask; 1793 pl->pl_siglist = td2->td_siglist; 1794 strcpy(pl->pl_tdname, td2->td_name); 1795 if (td2->td_sa.code != 0) { 1796 pl->pl_syscall_code = td2->td_sa.code; 1797 pl->pl_syscall_narg = td2->td_sa.callp->sy_narg; 1798 } 1799 CTR6(KTR_PTRACE, 1800 "PT_LWPINFO: tid %d (pid %d) event %d flags %#x child pid %d syscall %d", 1801 td2->td_tid, p->p_pid, pl->pl_event, pl->pl_flags, 1802 pl->pl_child_pid, pl->pl_syscall_code); 1803 break; 1804 1805 case PT_GETNUMLWPS: 1806 CTR2(KTR_PTRACE, "PT_GETNUMLWPS: pid %d: %d threads", p->p_pid, 1807 p->p_numthreads); 1808 td->td_retval[0] = p->p_numthreads; 1809 break; 1810 1811 case PT_GETLWPLIST: 1812 CTR3(KTR_PTRACE, "PT_GETLWPLIST: pid %d: data %d, actual %d", 1813 p->p_pid, data, p->p_numthreads); 1814 if (data <= 0) { 1815 error = EINVAL; 1816 break; 1817 } 1818 num = imin(p->p_numthreads, data); 1819 PROC_UNLOCK(p); 1820 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 1821 tmp = 0; 1822 PROC_LOCK(p); 1823 FOREACH_THREAD_IN_PROC(p, td2) { 1824 if (tmp >= num) 1825 break; 1826 buf[tmp++] = td2->td_tid; 1827 } 1828 PROC_UNLOCK(p); 1829 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 1830 free(buf, M_TEMP); 1831 if (!error) 1832 td->td_retval[0] = tmp; 1833 PROC_LOCK(p); 1834 break; 1835 1836 case PT_VM_TIMESTAMP: 1837 CTR2(KTR_PTRACE, "PT_VM_TIMESTAMP: pid %d: timestamp %d", 1838 p->p_pid, p->p_vmspace->vm_map.timestamp); 1839 td->td_retval[0] = p->p_vmspace->vm_map.timestamp; 1840 break; 1841 1842 case PT_VM_ENTRY: 1843 PROC_UNLOCK(p); 1844 error = ptrace_vm_entry(td, p, addr); 1845 PROC_LOCK(p); 1846 break; 1847 1848 case PT_COREDUMP: 1849 pc = addr; 1850 CTR2(KTR_PTRACE, "PT_COREDUMP: pid %d, fd %d", 1851 p->p_pid, pc->pc_fd); 1852 1853 if ((pc->pc_flags & ~(PC_COMPRESS | PC_ALL)) != 0) { 1854 error = EINVAL; 1855 break; 1856 } 1857 PROC_UNLOCK(p); 1858 1859 tcq = malloc(sizeof(*tcq), M_TEMP, M_WAITOK | M_ZERO); 1860 fp = NULL; 1861 error = fget_write(td, pc->pc_fd, &cap_write_rights, &fp); 1862 if (error != 0) 1863 goto coredump_cleanup_nofp; 1864 if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VREG) { 1865 error = EPIPE; 1866 goto coredump_cleanup; 1867 } 1868 1869 PROC_LOCK(p); 1870 error = proc_can_ptrace(td, p); 1871 if (error != 0) 1872 goto coredump_cleanup_locked; 1873 1874 td2 = ptrace_sel_coredump_thread(p); 1875 if (td2 == NULL) { 1876 error = EBUSY; 1877 goto coredump_cleanup_locked; 1878 } 1879 KASSERT((td2->td_dbgflags & (TDB_COREDUMPREQ | 1880 TDB_SCREMOTEREQ)) == 0, 1881 ("proc %d tid %d req coredump", p->p_pid, td2->td_tid)); 1882 1883 tcq->tc_vp = fp->f_vnode; 1884 tcq->tc_limit = pc->pc_limit == 0 ? OFF_MAX : pc->pc_limit; 1885 tcq->tc_flags = SVC_PT_COREDUMP; 1886 if ((pc->pc_flags & PC_COMPRESS) == 0) 1887 tcq->tc_flags |= SVC_NOCOMPRESS; 1888 if ((pc->pc_flags & PC_ALL) != 0) 1889 tcq->tc_flags |= SVC_ALL; 1890 td2->td_remotereq = tcq; 1891 td2->td_dbgflags |= TDB_COREDUMPREQ; 1892 thread_run_flash(td2); 1893 while ((td2->td_dbgflags & TDB_COREDUMPREQ) != 0) 1894 msleep(p, &p->p_mtx, PPAUSE, "crdmp", 0); 1895 error = tcq->tc_error; 1896 coredump_cleanup_locked: 1897 PROC_UNLOCK(p); 1898 coredump_cleanup: 1899 fdrop(fp, td); 1900 coredump_cleanup_nofp: 1901 free(tcq, M_TEMP); 1902 PROC_LOCK(p); 1903 break; 1904 1905 case PT_SC_REMOTE: 1906 pscr = addr; 1907 CTR2(KTR_PTRACE, "PT_SC_REMOTE: pid %d, syscall %d", 1908 p->p_pid, pscr->pscr_syscall); 1909 if ((td2->td_dbgflags & TDB_BOUNDARY) == 0) { 1910 error = EBUSY; 1911 break; 1912 } 1913 PROC_UNLOCK(p); 1914 MPASS(pscr->pscr_nargs <= nitems(td->td_sa.args)); 1915 1916 tsr = malloc(sizeof(struct thr_syscall_req), M_TEMP, 1917 M_WAITOK | M_ZERO); 1918 1919 tsr->ts_sa.code = pscr->pscr_syscall; 1920 tsr->ts_nargs = pscr->pscr_nargs; 1921 memcpy(&tsr->ts_sa.args, pscr->pscr_args, 1922 sizeof(syscallarg_t) * tsr->ts_nargs); 1923 1924 PROC_LOCK(p); 1925 error = proc_can_ptrace(td, p); 1926 if (error != 0) { 1927 free(tsr, M_TEMP); 1928 break; 1929 } 1930 if (td2->td_proc != p) { 1931 free(tsr, M_TEMP); 1932 error = ESRCH; 1933 break; 1934 } 1935 KASSERT((td2->td_dbgflags & (TDB_COREDUMPREQ | 1936 TDB_SCREMOTEREQ)) == 0, 1937 ("proc %d tid %d req coredump", p->p_pid, td2->td_tid)); 1938 1939 td2->td_remotereq = tsr; 1940 td2->td_dbgflags |= TDB_SCREMOTEREQ; 1941 thread_run_flash(td2); 1942 while ((td2->td_dbgflags & TDB_SCREMOTEREQ) != 0) 1943 msleep(p, &p->p_mtx, PPAUSE, "pscrx", 0); 1944 error = 0; 1945 memcpy(&pscr->pscr_ret, &tsr->ts_ret, sizeof(tsr->ts_ret)); 1946 free(tsr, M_TEMP); 1947 break; 1948 1949 case PT_GET_CHILDREN: 1950 PROC_UNLOCK(p); 1951 get_children_repeat: 1952 /* 1953 * If addr != NULL, we should ignore p_cansee() to 1954 * allocate enough space for the children array, 1955 * because the process is allowed to change visibility 1956 * between loops. But do not count children which 1957 * we cannot see when only returning the count, to 1958 * avoid a leak of information. 1959 */ 1960 num = ptrace_count_children(td, p, addr != NULL); 1961 1962 if (addr == NULL) { 1963 td->td_retval[0] = num; 1964 PROC_LOCK(p); 1965 break; 1966 } 1967 if (data < num * sizeof(struct ptrace_child)) { 1968 error = ENOMEM; 1969 PROC_LOCK(p); 1970 break; 1971 } 1972 sx_xunlock(&proctree_lock); 1973 children = mallocarray(num, sizeof(struct ptrace_child), 1974 M_TEMP, M_WAITOK | M_ZERO); 1975 sx_xlock(&proctree_lock); 1976 num1 = ptrace_count_children(td, p, true); 1977 if (num1 > num) { 1978 free(children, M_TEMP); 1979 goto get_children_repeat; 1980 } 1981 num = num1; 1982 num1 = 0; 1983 LIST_FOREACH(pp, &p->p_children, p_sibling) { 1984 MPASS(num1 < num); 1985 ptc = &children[num1]; 1986 if (ptrace_report_child(td, p, pp, ptc)) 1987 num1++; 1988 } 1989 LIST_FOREACH(pp, &p->p_orphans, p_orphan) { 1990 MPASS(num1 < num); 1991 ptc = &children[num1]; 1992 if (ptrace_report_child(td, p, pp, ptc)) { 1993 num1++; 1994 ptc->flags |= PTCHLD_ORPHAN; 1995 } 1996 } 1997 *(struct ptrace_child **)addr = children; 1998 td->td_retval[0] = num1; 1999 PROC_LOCK(p); 2000 break; 2001 2002 default: 2003 #ifdef __HAVE_PTRACE_MACHDEP 2004 if (req >= PT_FIRSTMACH) { 2005 PROC_UNLOCK(p); 2006 error = cpu_ptrace(td2, req, addr, data); 2007 PROC_LOCK(p); 2008 } else 2009 #endif 2010 /* Unknown request. */ 2011 error = EINVAL; 2012 break; 2013 } 2014 out: 2015 /* Drop our hold on this process now that the request has completed. */ 2016 _PRELE(p); 2017 fail: 2018 if (p2_req_set) { 2019 if ((p->p_flag2 & P2_PTRACEREQ) != 0) 2020 wakeup(&p->p_flag2); 2021 p->p_flag2 &= ~P2_PTRACEREQ; 2022 } 2023 PROC_UNLOCK(p); 2024 if (proctree_locked) 2025 sx_xunlock(&proctree_lock); 2026 return (error); 2027 } 2028 #undef PROC_READ 2029 #undef PROC_WRITE 2030