1 /*- 2 * Copyright (c) 1994, Sean Eric Fagan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by Sean Eric Fagan. 16 * 4. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_compat.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/lock.h> 40 #include <sys/mutex.h> 41 #include <sys/syscallsubr.h> 42 #include <sys/sysproto.h> 43 #include <sys/proc.h> 44 #include <sys/vnode.h> 45 #include <sys/ptrace.h> 46 #include <sys/sx.h> 47 #include <sys/malloc.h> 48 #include <sys/signalvar.h> 49 50 #include <machine/reg.h> 51 52 #include <security/audit/audit.h> 53 54 #include <vm/vm.h> 55 #include <vm/pmap.h> 56 #include <vm/vm_extern.h> 57 #include <vm/vm_map.h> 58 #include <vm/vm_kern.h> 59 #include <vm/vm_object.h> 60 #include <vm/vm_page.h> 61 62 #ifdef COMPAT_IA32 63 #include <sys/procfs.h> 64 #include <machine/fpu.h> 65 #include <compat/ia32/ia32_reg.h> 66 67 extern struct sysentvec ia32_freebsd_sysvec; 68 69 struct ptrace_io_desc32 { 70 int piod_op; 71 u_int32_t piod_offs; 72 u_int32_t piod_addr; 73 u_int32_t piod_len; 74 }; 75 #endif 76 77 /* 78 * Functions implemented using PROC_ACTION(): 79 * 80 * proc_read_regs(proc, regs) 81 * Get the current user-visible register set from the process 82 * and copy it into the regs structure (<machine/reg.h>). 83 * The process is stopped at the time read_regs is called. 84 * 85 * proc_write_regs(proc, regs) 86 * Update the current register set from the passed in regs 87 * structure. Take care to avoid clobbering special CPU 88 * registers or privileged bits in the PSL. 89 * Depending on the architecture this may have fix-up work to do, 90 * especially if the IAR or PCW are modified. 91 * The process is stopped at the time write_regs is called. 92 * 93 * proc_read_fpregs, proc_write_fpregs 94 * deal with the floating point register set, otherwise as above. 95 * 96 * proc_read_dbregs, proc_write_dbregs 97 * deal with the processor debug register set, otherwise as above. 98 * 99 * proc_sstep(proc) 100 * Arrange for the process to trap after executing a single instruction. 101 */ 102 103 #define PROC_ACTION(action) do { \ 104 int error; \ 105 \ 106 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ 107 if ((td->td_proc->p_flag & P_INMEM) == 0) \ 108 error = EIO; \ 109 else \ 110 error = (action); \ 111 return (error); \ 112 } while(0) 113 114 int 115 proc_read_regs(struct thread *td, struct reg *regs) 116 { 117 118 PROC_ACTION(fill_regs(td, regs)); 119 } 120 121 int 122 proc_write_regs(struct thread *td, struct reg *regs) 123 { 124 125 PROC_ACTION(set_regs(td, regs)); 126 } 127 128 int 129 proc_read_dbregs(struct thread *td, struct dbreg *dbregs) 130 { 131 132 PROC_ACTION(fill_dbregs(td, dbregs)); 133 } 134 135 int 136 proc_write_dbregs(struct thread *td, struct dbreg *dbregs) 137 { 138 139 PROC_ACTION(set_dbregs(td, dbregs)); 140 } 141 142 /* 143 * Ptrace doesn't support fpregs at all, and there are no security holes 144 * or translations for fpregs, so we can just copy them. 145 */ 146 int 147 proc_read_fpregs(struct thread *td, struct fpreg *fpregs) 148 { 149 150 PROC_ACTION(fill_fpregs(td, fpregs)); 151 } 152 153 int 154 proc_write_fpregs(struct thread *td, struct fpreg *fpregs) 155 { 156 157 PROC_ACTION(set_fpregs(td, fpregs)); 158 } 159 160 #ifdef COMPAT_IA32 161 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 162 int 163 proc_read_regs32(struct thread *td, struct reg32 *regs32) 164 { 165 166 PROC_ACTION(fill_regs32(td, regs32)); 167 } 168 169 int 170 proc_write_regs32(struct thread *td, struct reg32 *regs32) 171 { 172 173 PROC_ACTION(set_regs32(td, regs32)); 174 } 175 176 int 177 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 178 { 179 180 PROC_ACTION(fill_dbregs32(td, dbregs32)); 181 } 182 183 int 184 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 185 { 186 187 PROC_ACTION(set_dbregs32(td, dbregs32)); 188 } 189 190 int 191 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 192 { 193 194 PROC_ACTION(fill_fpregs32(td, fpregs32)); 195 } 196 197 int 198 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 199 { 200 201 PROC_ACTION(set_fpregs32(td, fpregs32)); 202 } 203 #endif 204 205 int 206 proc_sstep(struct thread *td) 207 { 208 209 PROC_ACTION(ptrace_single_step(td)); 210 } 211 212 int 213 proc_rwmem(struct proc *p, struct uio *uio) 214 { 215 vm_map_t map; 216 vm_object_t backing_object, object = NULL; 217 vm_offset_t pageno = 0; /* page number */ 218 vm_prot_t reqprot; 219 int error, fault_flags, writing; 220 221 /* 222 * Assert that someone has locked this vmspace. (Should be 223 * curthread but we can't assert that.) This keeps the process 224 * from exiting out from under us until this operation completes. 225 */ 226 KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__, 227 p, p->p_pid)); 228 229 /* 230 * The map we want... 231 */ 232 map = &p->p_vmspace->vm_map; 233 234 writing = uio->uio_rw == UIO_WRITE; 235 reqprot = writing ? (VM_PROT_WRITE | VM_PROT_OVERRIDE_WRITE) : 236 VM_PROT_READ; 237 fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 238 239 /* 240 * Only map in one page at a time. We don't have to, but it 241 * makes things easier. This way is trivial - right? 242 */ 243 do { 244 vm_map_t tmap; 245 vm_offset_t uva; 246 int page_offset; /* offset into page */ 247 vm_map_entry_t out_entry; 248 vm_prot_t out_prot; 249 boolean_t wired; 250 vm_pindex_t pindex; 251 u_int len; 252 vm_page_t m; 253 254 object = NULL; 255 256 uva = (vm_offset_t)uio->uio_offset; 257 258 /* 259 * Get the page number of this segment. 260 */ 261 pageno = trunc_page(uva); 262 page_offset = uva - pageno; 263 264 /* 265 * How many bytes to copy 266 */ 267 len = min(PAGE_SIZE - page_offset, uio->uio_resid); 268 269 /* 270 * Fault the page on behalf of the process 271 */ 272 error = vm_fault(map, pageno, reqprot, fault_flags); 273 if (error) { 274 error = EFAULT; 275 break; 276 } 277 278 /* 279 * Now we need to get the page. out_entry, out_prot, wired, 280 * and single_use aren't used. One would think the vm code 281 * would be a *bit* nicer... We use tmap because 282 * vm_map_lookup() can change the map argument. 283 */ 284 tmap = map; 285 error = vm_map_lookup(&tmap, pageno, reqprot, &out_entry, 286 &object, &pindex, &out_prot, &wired); 287 if (error) { 288 error = EFAULT; 289 break; 290 } 291 VM_OBJECT_LOCK(object); 292 while ((m = vm_page_lookup(object, pindex)) == NULL && 293 !writing && 294 (backing_object = object->backing_object) != NULL) { 295 /* 296 * Allow fallback to backing objects if we are reading. 297 */ 298 VM_OBJECT_LOCK(backing_object); 299 pindex += OFF_TO_IDX(object->backing_object_offset); 300 VM_OBJECT_UNLOCK(object); 301 object = backing_object; 302 } 303 VM_OBJECT_UNLOCK(object); 304 if (m == NULL) { 305 vm_map_lookup_done(tmap, out_entry); 306 error = EFAULT; 307 break; 308 } 309 310 /* 311 * Hold the page in memory. 312 */ 313 vm_page_lock_queues(); 314 vm_page_hold(m); 315 vm_page_unlock_queues(); 316 317 /* 318 * We're done with tmap now. 319 */ 320 vm_map_lookup_done(tmap, out_entry); 321 322 /* 323 * Now do the i/o move. 324 */ 325 error = uiomove_fromphys(&m, page_offset, len, uio); 326 327 /* 328 * Release the page. 329 */ 330 vm_page_lock_queues(); 331 vm_page_unhold(m); 332 vm_page_unlock_queues(); 333 334 } while (error == 0 && uio->uio_resid > 0); 335 336 return (error); 337 } 338 339 /* 340 * Process debugging system call. 341 */ 342 #ifndef _SYS_SYSPROTO_H_ 343 struct ptrace_args { 344 int req; 345 pid_t pid; 346 caddr_t addr; 347 int data; 348 }; 349 #endif 350 351 #ifdef COMPAT_IA32 352 /* 353 * This CPP subterfuge is to try and reduce the number of ifdefs in 354 * the body of the code. 355 * COPYIN(uap->addr, &r.reg, sizeof r.reg); 356 * becomes either: 357 * copyin(uap->addr, &r.reg, sizeof r.reg); 358 * or 359 * copyin(uap->addr, &r.reg32, sizeof r.reg32); 360 * .. except this is done at runtime. 361 */ 362 #define COPYIN(u, k, s) wrap32 ? \ 363 copyin(u, k ## 32, s ## 32) : \ 364 copyin(u, k, s) 365 #define COPYOUT(k, u, s) wrap32 ? \ 366 copyout(k ## 32, u, s ## 32) : \ 367 copyout(k, u, s) 368 #else 369 #define COPYIN(u, k, s) copyin(u, k, s) 370 #define COPYOUT(k, u, s) copyout(k, u, s) 371 #endif 372 int 373 ptrace(struct thread *td, struct ptrace_args *uap) 374 { 375 /* 376 * XXX this obfuscation is to reduce stack usage, but the register 377 * structs may be too large to put on the stack anyway. 378 */ 379 union { 380 struct ptrace_io_desc piod; 381 struct ptrace_lwpinfo pl; 382 struct dbreg dbreg; 383 struct fpreg fpreg; 384 struct reg reg; 385 #ifdef COMPAT_IA32 386 struct dbreg32 dbreg32; 387 struct fpreg32 fpreg32; 388 struct reg32 reg32; 389 struct ptrace_io_desc32 piod32; 390 #endif 391 } r; 392 void *addr; 393 int error = 0; 394 #ifdef COMPAT_IA32 395 int wrap32 = 0; 396 397 if (td->td_proc->p_sysent == &ia32_freebsd_sysvec) 398 wrap32 = 1; 399 #endif 400 AUDIT_ARG(pid, uap->pid); 401 AUDIT_ARG(cmd, uap->req); 402 AUDIT_ARG(addr, uap->addr); 403 AUDIT_ARG(value, uap->data); 404 addr = &r; 405 switch (uap->req) { 406 case PT_GETREGS: 407 case PT_GETFPREGS: 408 case PT_GETDBREGS: 409 case PT_LWPINFO: 410 break; 411 case PT_SETREGS: 412 error = COPYIN(uap->addr, &r.reg, sizeof r.reg); 413 break; 414 case PT_SETFPREGS: 415 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); 416 break; 417 case PT_SETDBREGS: 418 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); 419 break; 420 case PT_IO: 421 error = COPYIN(uap->addr, &r.piod, sizeof r.piod); 422 break; 423 default: 424 addr = uap->addr; 425 break; 426 } 427 if (error) 428 return (error); 429 430 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 431 if (error) 432 return (error); 433 434 switch (uap->req) { 435 case PT_IO: 436 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); 437 break; 438 case PT_GETREGS: 439 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); 440 break; 441 case PT_GETFPREGS: 442 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); 443 break; 444 case PT_GETDBREGS: 445 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); 446 break; 447 case PT_LWPINFO: 448 error = copyout(&r.pl, uap->addr, uap->data); 449 break; 450 } 451 452 return (error); 453 } 454 #undef COPYIN 455 #undef COPYOUT 456 457 #ifdef COMPAT_IA32 458 /* 459 * PROC_READ(regs, td2, addr); 460 * becomes either: 461 * proc_read_regs(td2, addr); 462 * or 463 * proc_read_regs32(td2, addr); 464 * .. except this is done at runtime. There is an additional 465 * complication in that PROC_WRITE disallows 32 bit consumers 466 * from writing to 64 bit address space targets. 467 */ 468 #define PROC_READ(w, t, a) wrap32 ? \ 469 proc_read_ ## w ## 32(t, a) : \ 470 proc_read_ ## w (t, a) 471 #define PROC_WRITE(w, t, a) wrap32 ? \ 472 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 473 proc_write_ ## w (t, a) 474 #else 475 #define PROC_READ(w, t, a) proc_read_ ## w (t, a) 476 #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 477 #endif 478 479 int 480 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 481 { 482 struct iovec iov; 483 struct uio uio; 484 struct proc *curp, *p, *pp; 485 struct thread *td2 = NULL; 486 struct ptrace_io_desc *piod = NULL; 487 struct ptrace_lwpinfo *pl; 488 int error, write, tmp, num; 489 int proctree_locked = 0; 490 lwpid_t tid = 0, *buf; 491 #ifdef COMPAT_IA32 492 int wrap32 = 0, safe = 0; 493 struct ptrace_io_desc32 *piod32 = NULL; 494 #endif 495 496 curp = td->td_proc; 497 498 /* Lock proctree before locking the process. */ 499 switch (req) { 500 case PT_TRACE_ME: 501 case PT_ATTACH: 502 case PT_STEP: 503 case PT_CONTINUE: 504 case PT_TO_SCE: 505 case PT_TO_SCX: 506 case PT_SYSCALL: 507 case PT_DETACH: 508 sx_xlock(&proctree_lock); 509 proctree_locked = 1; 510 break; 511 default: 512 break; 513 } 514 515 write = 0; 516 if (req == PT_TRACE_ME) { 517 p = td->td_proc; 518 PROC_LOCK(p); 519 } else { 520 if (pid <= PID_MAX) { 521 if ((p = pfind(pid)) == NULL) { 522 if (proctree_locked) 523 sx_xunlock(&proctree_lock); 524 return (ESRCH); 525 } 526 } else { 527 /* this is slow, should be optimized */ 528 sx_slock(&allproc_lock); 529 FOREACH_PROC_IN_SYSTEM(p) { 530 PROC_LOCK(p); 531 FOREACH_THREAD_IN_PROC(p, td2) { 532 if (td2->td_tid == pid) 533 break; 534 } 535 if (td2 != NULL) 536 break; /* proc lock held */ 537 PROC_UNLOCK(p); 538 } 539 sx_sunlock(&allproc_lock); 540 if (p == NULL) { 541 if (proctree_locked) 542 sx_xunlock(&proctree_lock); 543 return (ESRCH); 544 } 545 tid = pid; 546 pid = p->p_pid; 547 } 548 } 549 AUDIT_ARG(process, p); 550 551 if ((p->p_flag & P_WEXIT) != 0) { 552 error = ESRCH; 553 goto fail; 554 } 555 if ((error = p_cansee(td, p)) != 0) 556 goto fail; 557 558 if ((error = p_candebug(td, p)) != 0) 559 goto fail; 560 561 /* 562 * System processes can't be debugged. 563 */ 564 if ((p->p_flag & P_SYSTEM) != 0) { 565 error = EINVAL; 566 goto fail; 567 } 568 569 if (tid == 0) { 570 if ((p->p_flag & P_STOPPED_TRACE) != 0) { 571 KASSERT(p->p_xthread != NULL, ("NULL p_xthread")); 572 td2 = p->p_xthread; 573 } else { 574 td2 = FIRST_THREAD_IN_PROC(p); 575 } 576 tid = td2->td_tid; 577 } 578 579 #ifdef COMPAT_IA32 580 /* 581 * Test if we're a 32 bit client and what the target is. 582 * Set the wrap controls accordingly. 583 */ 584 if (td->td_proc->p_sysent == &ia32_freebsd_sysvec) { 585 if (td2->td_proc->p_sysent == &ia32_freebsd_sysvec) 586 safe = 1; 587 wrap32 = 1; 588 } 589 #endif 590 /* 591 * Permissions check 592 */ 593 switch (req) { 594 case PT_TRACE_ME: 595 /* Always legal. */ 596 break; 597 598 case PT_ATTACH: 599 /* Self */ 600 if (p->p_pid == td->td_proc->p_pid) { 601 error = EINVAL; 602 goto fail; 603 } 604 605 /* Already traced */ 606 if (p->p_flag & P_TRACED) { 607 error = EBUSY; 608 goto fail; 609 } 610 611 /* Can't trace an ancestor if you're being traced. */ 612 if (curp->p_flag & P_TRACED) { 613 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 614 if (pp == p) { 615 error = EINVAL; 616 goto fail; 617 } 618 } 619 } 620 621 622 /* OK */ 623 break; 624 625 case PT_CLEARSTEP: 626 /* Allow thread to clear single step for itself */ 627 if (td->td_tid == tid) 628 break; 629 630 /* FALLTHROUGH */ 631 default: 632 /* not being traced... */ 633 if ((p->p_flag & P_TRACED) == 0) { 634 error = EPERM; 635 goto fail; 636 } 637 638 /* not being traced by YOU */ 639 if (p->p_pptr != td->td_proc) { 640 error = EBUSY; 641 goto fail; 642 } 643 644 /* not currently stopped */ 645 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 || 646 p->p_suspcount != p->p_numthreads || 647 (p->p_flag & P_WAITED) == 0) { 648 error = EBUSY; 649 goto fail; 650 } 651 652 if ((p->p_flag & P_STOPPED_TRACE) == 0) { 653 static int count = 0; 654 if (count++ == 0) 655 printf("P_STOPPED_TRACE not set.\n"); 656 } 657 658 /* OK */ 659 break; 660 } 661 662 /* Keep this process around until we finish this request. */ 663 _PHOLD(p); 664 665 #ifdef FIX_SSTEP 666 /* 667 * Single step fixup ala procfs 668 */ 669 FIX_SSTEP(td2); 670 #endif 671 672 /* 673 * Actually do the requests 674 */ 675 676 td->td_retval[0] = 0; 677 678 switch (req) { 679 case PT_TRACE_ME: 680 /* set my trace flag and "owner" so it can read/write me */ 681 p->p_flag |= P_TRACED; 682 p->p_oppid = p->p_pptr->p_pid; 683 break; 684 685 case PT_ATTACH: 686 /* security check done above */ 687 p->p_flag |= P_TRACED; 688 p->p_oppid = p->p_pptr->p_pid; 689 if (p->p_pptr != td->td_proc) 690 proc_reparent(p, td->td_proc); 691 data = SIGSTOP; 692 goto sendsig; /* in PT_CONTINUE below */ 693 694 case PT_CLEARSTEP: 695 error = ptrace_clear_single_step(td2); 696 break; 697 698 case PT_SETSTEP: 699 error = ptrace_single_step(td2); 700 break; 701 702 case PT_SUSPEND: 703 td2->td_dbgflags |= TDB_SUSPEND; 704 thread_lock(td2); 705 td2->td_flags |= TDF_NEEDSUSPCHK; 706 thread_unlock(td2); 707 break; 708 709 case PT_RESUME: 710 td2->td_dbgflags &= ~TDB_SUSPEND; 711 break; 712 713 case PT_STEP: 714 case PT_CONTINUE: 715 case PT_TO_SCE: 716 case PT_TO_SCX: 717 case PT_SYSCALL: 718 case PT_DETACH: 719 /* Zero means do not send any signal */ 720 if (data < 0 || data > _SIG_MAXSIG) { 721 error = EINVAL; 722 break; 723 } 724 725 switch (req) { 726 case PT_STEP: 727 error = ptrace_single_step(td2); 728 if (error) 729 goto out; 730 break; 731 case PT_TO_SCE: 732 p->p_stops |= S_PT_SCE; 733 break; 734 case PT_TO_SCX: 735 p->p_stops |= S_PT_SCX; 736 break; 737 case PT_SYSCALL: 738 p->p_stops |= S_PT_SCE | S_PT_SCX; 739 break; 740 } 741 742 if (addr != (void *)1) { 743 error = ptrace_set_pc(td2, (u_long)(uintfptr_t)addr); 744 if (error) 745 break; 746 } 747 748 if (req == PT_DETACH) { 749 /* reset process parent */ 750 if (p->p_oppid != p->p_pptr->p_pid) { 751 struct proc *pp; 752 753 PROC_LOCK(p->p_pptr); 754 sigqueue_take(p->p_ksi); 755 PROC_UNLOCK(p->p_pptr); 756 757 PROC_UNLOCK(p); 758 pp = pfind(p->p_oppid); 759 if (pp == NULL) 760 pp = initproc; 761 else 762 PROC_UNLOCK(pp); 763 PROC_LOCK(p); 764 proc_reparent(p, pp); 765 if (pp == initproc) 766 p->p_sigparent = SIGCHLD; 767 } 768 p->p_flag &= ~(P_TRACED | P_WAITED); 769 p->p_oppid = 0; 770 771 /* should we send SIGCHLD? */ 772 /* childproc_continued(p); */ 773 } 774 775 sendsig: 776 if (proctree_locked) { 777 sx_xunlock(&proctree_lock); 778 proctree_locked = 0; 779 } 780 p->p_xstat = data; 781 p->p_xthread = NULL; 782 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) { 783 /* deliver or queue signal */ 784 td2->td_dbgflags &= ~TDB_XSIG; 785 td2->td_xsig = data; 786 787 if (req == PT_DETACH) { 788 struct thread *td3; 789 FOREACH_THREAD_IN_PROC(p, td3) { 790 td3->td_dbgflags &= ~TDB_SUSPEND; 791 } 792 } 793 /* 794 * unsuspend all threads, to not let a thread run, 795 * you should use PT_SUSPEND to suspend it before 796 * continuing process. 797 */ 798 PROC_SLOCK(p); 799 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED); 800 thread_unsuspend(p); 801 PROC_SUNLOCK(p); 802 } else { 803 if (data) 804 psignal(p, data); 805 } 806 break; 807 808 case PT_WRITE_I: 809 case PT_WRITE_D: 810 write = 1; 811 /* FALLTHROUGH */ 812 case PT_READ_I: 813 case PT_READ_D: 814 PROC_UNLOCK(p); 815 tmp = 0; 816 /* write = 0 set above */ 817 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 818 iov.iov_len = sizeof(int); 819 uio.uio_iov = &iov; 820 uio.uio_iovcnt = 1; 821 uio.uio_offset = (off_t)(uintptr_t)addr; 822 uio.uio_resid = sizeof(int); 823 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */ 824 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 825 uio.uio_td = td; 826 error = proc_rwmem(p, &uio); 827 if (uio.uio_resid != 0) { 828 /* 829 * XXX proc_rwmem() doesn't currently return ENOSPC, 830 * so I think write() can bogusly return 0. 831 * XXX what happens for short writes? We don't want 832 * to write partial data. 833 * XXX proc_rwmem() returns EPERM for other invalid 834 * addresses. Convert this to EINVAL. Does this 835 * clobber returns of EPERM for other reasons? 836 */ 837 if (error == 0 || error == ENOSPC || error == EPERM) 838 error = EINVAL; /* EOF */ 839 } 840 if (!write) 841 td->td_retval[0] = tmp; 842 PROC_LOCK(p); 843 break; 844 845 case PT_IO: 846 #ifdef COMPAT_IA32 847 if (wrap32) { 848 piod32 = addr; 849 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; 850 iov.iov_len = piod32->piod_len; 851 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; 852 uio.uio_resid = piod32->piod_len; 853 } else 854 #endif 855 { 856 piod = addr; 857 iov.iov_base = piod->piod_addr; 858 iov.iov_len = piod->piod_len; 859 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 860 uio.uio_resid = piod->piod_len; 861 } 862 uio.uio_iov = &iov; 863 uio.uio_iovcnt = 1; 864 uio.uio_segflg = UIO_USERSPACE; 865 uio.uio_td = td; 866 #ifdef COMPAT_IA32 867 tmp = wrap32 ? piod32->piod_op : piod->piod_op; 868 #else 869 tmp = piod->piod_op; 870 #endif 871 switch (tmp) { 872 case PIOD_READ_D: 873 case PIOD_READ_I: 874 uio.uio_rw = UIO_READ; 875 break; 876 case PIOD_WRITE_D: 877 case PIOD_WRITE_I: 878 uio.uio_rw = UIO_WRITE; 879 break; 880 default: 881 error = EINVAL; 882 goto out; 883 } 884 PROC_UNLOCK(p); 885 error = proc_rwmem(p, &uio); 886 #ifdef COMPAT_IA32 887 if (wrap32) 888 piod32->piod_len -= uio.uio_resid; 889 else 890 #endif 891 piod->piod_len -= uio.uio_resid; 892 PROC_LOCK(p); 893 break; 894 895 case PT_KILL: 896 data = SIGKILL; 897 goto sendsig; /* in PT_CONTINUE above */ 898 899 case PT_SETREGS: 900 error = PROC_WRITE(regs, td2, addr); 901 break; 902 903 case PT_GETREGS: 904 error = PROC_READ(regs, td2, addr); 905 break; 906 907 case PT_SETFPREGS: 908 error = PROC_WRITE(fpregs, td2, addr); 909 break; 910 911 case PT_GETFPREGS: 912 error = PROC_READ(fpregs, td2, addr); 913 break; 914 915 case PT_SETDBREGS: 916 error = PROC_WRITE(dbregs, td2, addr); 917 break; 918 919 case PT_GETDBREGS: 920 error = PROC_READ(dbregs, td2, addr); 921 break; 922 923 case PT_LWPINFO: 924 if (data <= 0 || data > sizeof(*pl)) { 925 error = EINVAL; 926 break; 927 } 928 pl = addr; 929 pl->pl_lwpid = td2->td_tid; 930 if (td2->td_dbgflags & TDB_XSIG) 931 pl->pl_event = PL_EVENT_SIGNAL; 932 else 933 pl->pl_event = 0; 934 pl->pl_flags = 0; 935 pl->pl_sigmask = td2->td_sigmask; 936 pl->pl_siglist = td2->td_siglist; 937 break; 938 939 case PT_GETNUMLWPS: 940 td->td_retval[0] = p->p_numthreads; 941 break; 942 943 case PT_GETLWPLIST: 944 if (data <= 0) { 945 error = EINVAL; 946 break; 947 } 948 num = imin(p->p_numthreads, data); 949 PROC_UNLOCK(p); 950 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 951 tmp = 0; 952 PROC_LOCK(p); 953 FOREACH_THREAD_IN_PROC(p, td2) { 954 if (tmp >= num) 955 break; 956 buf[tmp++] = td2->td_tid; 957 } 958 PROC_UNLOCK(p); 959 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 960 free(buf, M_TEMP); 961 if (!error) 962 td->td_retval[0] = tmp; 963 PROC_LOCK(p); 964 break; 965 966 default: 967 #ifdef __HAVE_PTRACE_MACHDEP 968 if (req >= PT_FIRSTMACH) { 969 PROC_UNLOCK(p); 970 error = cpu_ptrace(td2, req, addr, data); 971 PROC_LOCK(p); 972 } else 973 #endif 974 /* Unknown request. */ 975 error = EINVAL; 976 break; 977 } 978 979 out: 980 /* Drop our hold on this process now that the request has completed. */ 981 _PRELE(p); 982 fail: 983 PROC_UNLOCK(p); 984 if (proctree_locked) 985 sx_xunlock(&proctree_lock); 986 return (error); 987 } 988 #undef PROC_READ 989 #undef PROC_WRITE 990 991 /* 992 * Stop a process because of a debugging event; 993 * stay stopped until p->p_step is cleared 994 * (cleared by PIOCCONT in procfs). 995 */ 996 void 997 stopevent(struct proc *p, unsigned int event, unsigned int val) 998 { 999 1000 PROC_LOCK_ASSERT(p, MA_OWNED); 1001 p->p_step = 1; 1002 do { 1003 p->p_xstat = val; 1004 p->p_xthread = NULL; 1005 p->p_stype = event; /* Which event caused the stop? */ 1006 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ 1007 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); 1008 } while (p->p_step); 1009 } 1010