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 <vm/vm.h> 53 #include <vm/pmap.h> 54 #include <vm/vm_extern.h> 55 #include <vm/vm_map.h> 56 #include <vm/vm_kern.h> 57 #include <vm/vm_object.h> 58 #include <vm/vm_page.h> 59 60 #ifdef COMPAT_IA32 61 #include <sys/procfs.h> 62 #include <machine/fpu.h> 63 #include <compat/ia32/ia32_reg.h> 64 65 extern struct sysentvec ia32_freebsd_sysvec; 66 67 struct ptrace_io_desc32 { 68 int piod_op; 69 u_int32_t piod_offs; 70 u_int32_t piod_addr; 71 u_int32_t piod_len; 72 }; 73 #endif 74 75 /* 76 * Functions implemented using PROC_ACTION(): 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 #define PROC_ACTION(action) do { \ 102 int error; \ 103 \ 104 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ 105 if ((td->td_proc->p_sflag & PS_INMEM) == 0) \ 106 error = EIO; \ 107 else \ 108 error = (action); \ 109 return (error); \ 110 } while(0) 111 112 int 113 proc_read_regs(struct thread *td, struct reg *regs) 114 { 115 116 PROC_ACTION(fill_regs(td, regs)); 117 } 118 119 int 120 proc_write_regs(struct thread *td, struct reg *regs) 121 { 122 123 PROC_ACTION(set_regs(td, regs)); 124 } 125 126 int 127 proc_read_dbregs(struct thread *td, struct dbreg *dbregs) 128 { 129 130 PROC_ACTION(fill_dbregs(td, dbregs)); 131 } 132 133 int 134 proc_write_dbregs(struct thread *td, struct dbreg *dbregs) 135 { 136 137 PROC_ACTION(set_dbregs(td, dbregs)); 138 } 139 140 /* 141 * Ptrace doesn't support fpregs at all, and there are no security holes 142 * or translations for fpregs, so we can just copy them. 143 */ 144 int 145 proc_read_fpregs(struct thread *td, struct fpreg *fpregs) 146 { 147 148 PROC_ACTION(fill_fpregs(td, fpregs)); 149 } 150 151 int 152 proc_write_fpregs(struct thread *td, struct fpreg *fpregs) 153 { 154 155 PROC_ACTION(set_fpregs(td, fpregs)); 156 } 157 158 #ifdef COMPAT_IA32 159 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 160 int 161 proc_read_regs32(struct thread *td, struct reg32 *regs32) 162 { 163 164 PROC_ACTION(fill_regs32(td, regs32)); 165 } 166 167 int 168 proc_write_regs32(struct thread *td, struct reg32 *regs32) 169 { 170 171 PROC_ACTION(set_regs32(td, regs32)); 172 } 173 174 int 175 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 176 { 177 178 PROC_ACTION(fill_dbregs32(td, dbregs32)); 179 } 180 181 int 182 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 183 { 184 185 PROC_ACTION(set_dbregs32(td, dbregs32)); 186 } 187 188 int 189 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 190 { 191 192 PROC_ACTION(fill_fpregs32(td, fpregs32)); 193 } 194 195 int 196 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 197 { 198 199 PROC_ACTION(set_fpregs32(td, fpregs32)); 200 } 201 #endif 202 203 int 204 proc_sstep(struct thread *td) 205 { 206 207 PROC_ACTION(ptrace_single_step(td)); 208 } 209 210 int 211 proc_rwmem(struct proc *p, struct uio *uio) 212 { 213 struct vmspace *vm; 214 vm_map_t map; 215 vm_object_t backing_object, object = NULL; 216 vm_offset_t pageno = 0; /* page number */ 217 vm_prot_t reqprot; 218 int error, refcnt, writing; 219 220 /* 221 * if the vmspace is in the midst of being deallocated or the 222 * process is exiting, don't try to grab anything. The page table 223 * usage in that process can be messed up. 224 */ 225 vm = p->p_vmspace; 226 if ((p->p_flag & P_WEXIT)) 227 return (EFAULT); 228 do { 229 if ((refcnt = vm->vm_refcnt) < 1) 230 return (EFAULT); 231 } while (!atomic_cmpset_int(&vm->vm_refcnt, refcnt, refcnt + 1)); 232 233 /* 234 * The map we want... 235 */ 236 map = &vm->vm_map; 237 238 writing = uio->uio_rw == UIO_WRITE; 239 reqprot = writing ? (VM_PROT_WRITE | VM_PROT_OVERRIDE_WRITE) : 240 VM_PROT_READ; 241 242 /* 243 * Only map in one page at a time. We don't have to, but it 244 * makes things easier. This way is trivial - right? 245 */ 246 do { 247 vm_map_t tmap; 248 vm_offset_t uva; 249 int page_offset; /* offset into page */ 250 vm_map_entry_t out_entry; 251 vm_prot_t out_prot; 252 boolean_t wired; 253 vm_pindex_t pindex; 254 u_int len; 255 vm_page_t m; 256 257 object = NULL; 258 259 uva = (vm_offset_t)uio->uio_offset; 260 261 /* 262 * Get the page number of this segment. 263 */ 264 pageno = trunc_page(uva); 265 page_offset = uva - pageno; 266 267 /* 268 * How many bytes to copy 269 */ 270 len = min(PAGE_SIZE - page_offset, uio->uio_resid); 271 272 /* 273 * Fault the page on behalf of the process 274 */ 275 error = vm_fault(map, pageno, reqprot, VM_FAULT_NORMAL); 276 if (error) { 277 error = EFAULT; 278 break; 279 } 280 281 /* 282 * Now we need to get the page. out_entry, out_prot, wired, 283 * and single_use aren't used. One would think the vm code 284 * would be a *bit* nicer... We use tmap because 285 * vm_map_lookup() can change the map argument. 286 */ 287 tmap = map; 288 error = vm_map_lookup(&tmap, pageno, reqprot, &out_entry, 289 &object, &pindex, &out_prot, &wired); 290 if (error) { 291 error = EFAULT; 292 break; 293 } 294 VM_OBJECT_LOCK(object); 295 while ((m = vm_page_lookup(object, pindex)) == NULL && 296 !writing && 297 (backing_object = object->backing_object) != NULL) { 298 /* 299 * Allow fallback to backing objects if we are reading. 300 */ 301 VM_OBJECT_LOCK(backing_object); 302 pindex += OFF_TO_IDX(object->backing_object_offset); 303 VM_OBJECT_UNLOCK(object); 304 object = backing_object; 305 } 306 VM_OBJECT_UNLOCK(object); 307 if (m == NULL) { 308 vm_map_lookup_done(tmap, out_entry); 309 error = EFAULT; 310 break; 311 } 312 313 /* 314 * Hold the page in memory. 315 */ 316 vm_page_lock_queues(); 317 vm_page_hold(m); 318 vm_page_unlock_queues(); 319 320 /* 321 * We're done with tmap now. 322 */ 323 vm_map_lookup_done(tmap, out_entry); 324 325 /* 326 * Now do the i/o move. 327 */ 328 error = uiomove_fromphys(&m, page_offset, len, uio); 329 330 /* 331 * Release the page. 332 */ 333 vm_page_lock_queues(); 334 vm_page_unhold(m); 335 vm_page_unlock_queues(); 336 337 } while (error == 0 && uio->uio_resid > 0); 338 339 vmspace_free(vm); 340 return (error); 341 } 342 343 /* 344 * Process debugging system call. 345 */ 346 #ifndef _SYS_SYSPROTO_H_ 347 struct ptrace_args { 348 int req; 349 pid_t pid; 350 caddr_t addr; 351 int data; 352 }; 353 #endif 354 355 #ifdef COMPAT_IA32 356 /* 357 * This CPP subterfuge is to try and reduce the number of ifdefs in 358 * the body of the code. 359 * COPYIN(uap->addr, &r.reg, sizeof r.reg); 360 * becomes either: 361 * copyin(uap->addr, &r.reg, sizeof r.reg); 362 * or 363 * copyin(uap->addr, &r.reg32, sizeof r.reg32); 364 * .. except this is done at runtime. 365 */ 366 #define COPYIN(u, k, s) wrap32 ? \ 367 copyin(u, k ## 32, s ## 32) : \ 368 copyin(u, k, s) 369 #define COPYOUT(k, u, s) wrap32 ? \ 370 copyout(k ## 32, u, s ## 32) : \ 371 copyout(k, u, s) 372 #else 373 #define COPYIN(u, k, s) copyin(u, k, s) 374 #define COPYOUT(k, u, s) copyout(k, u, s) 375 #endif 376 /* 377 * MPSAFE 378 */ 379 int 380 ptrace(struct thread *td, struct ptrace_args *uap) 381 { 382 /* 383 * XXX this obfuscation is to reduce stack usage, but the register 384 * structs may be too large to put on the stack anyway. 385 */ 386 union { 387 struct ptrace_io_desc piod; 388 struct ptrace_lwpinfo pl; 389 struct dbreg dbreg; 390 struct fpreg fpreg; 391 struct reg reg; 392 #ifdef COMPAT_IA32 393 struct dbreg32 dbreg32; 394 struct fpreg32 fpreg32; 395 struct reg32 reg32; 396 struct ptrace_io_desc32 piod32; 397 #endif 398 } r; 399 void *addr; 400 int error = 0; 401 #ifdef COMPAT_IA32 402 int wrap32 = 0; 403 404 if (td->td_proc->p_sysent == &ia32_freebsd_sysvec) 405 wrap32 = 1; 406 #endif 407 addr = &r; 408 switch (uap->req) { 409 case PT_GETREGS: 410 case PT_GETFPREGS: 411 case PT_GETDBREGS: 412 case PT_LWPINFO: 413 break; 414 case PT_SETREGS: 415 error = COPYIN(uap->addr, &r.reg, sizeof r.reg); 416 break; 417 case PT_SETFPREGS: 418 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); 419 break; 420 case PT_SETDBREGS: 421 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); 422 break; 423 case PT_IO: 424 error = COPYIN(uap->addr, &r.piod, sizeof r.piod); 425 break; 426 default: 427 addr = uap->addr; 428 break; 429 } 430 if (error) 431 return (error); 432 433 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 434 if (error) 435 return (error); 436 437 switch (uap->req) { 438 case PT_IO: 439 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); 440 break; 441 case PT_GETREGS: 442 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); 443 break; 444 case PT_GETFPREGS: 445 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); 446 break; 447 case PT_GETDBREGS: 448 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); 449 break; 450 case PT_LWPINFO: 451 error = copyout(&r.pl, uap->addr, uap->data); 452 break; 453 } 454 455 return (error); 456 } 457 #undef COPYIN 458 #undef COPYOUT 459 460 #ifdef COMPAT_IA32 461 /* 462 * PROC_READ(regs, td2, addr); 463 * becomes either: 464 * proc_read_regs(td2, addr); 465 * or 466 * proc_read_regs32(td2, addr); 467 * .. except this is done at runtime. There is an additional 468 * complication in that PROC_WRITE disallows 32 bit consumers 469 * from writing to 64 bit address space targets. 470 */ 471 #define PROC_READ(w, t, a) wrap32 ? \ 472 proc_read_ ## w ## 32(t, a) : \ 473 proc_read_ ## w (t, a) 474 #define PROC_WRITE(w, t, a) wrap32 ? \ 475 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 476 proc_write_ ## w (t, a) 477 #else 478 #define PROC_READ(w, t, a) proc_read_ ## w (t, a) 479 #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 480 #endif 481 482 int 483 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 484 { 485 struct iovec iov; 486 struct uio uio; 487 struct proc *curp, *p, *pp; 488 struct thread *td2 = NULL; 489 struct ptrace_io_desc *piod = NULL; 490 struct ptrace_lwpinfo *pl; 491 int error, write, tmp, num; 492 int proctree_locked = 0; 493 lwpid_t tid = 0, *buf; 494 pid_t saved_pid = pid; 495 #ifdef COMPAT_IA32 496 int wrap32 = 0, safe = 0; 497 struct ptrace_io_desc32 *piod32 = NULL; 498 #endif 499 500 curp = td->td_proc; 501 502 /* Lock proctree before locking the process. */ 503 switch (req) { 504 case PT_TRACE_ME: 505 case PT_ATTACH: 506 case PT_STEP: 507 case PT_CONTINUE: 508 case PT_TO_SCE: 509 case PT_TO_SCX: 510 case PT_SYSCALL: 511 case PT_DETACH: 512 sx_xlock(&proctree_lock); 513 proctree_locked = 1; 514 break; 515 default: 516 break; 517 } 518 519 write = 0; 520 if (req == PT_TRACE_ME) { 521 p = td->td_proc; 522 PROC_LOCK(p); 523 } else { 524 if (pid <= PID_MAX) { 525 if ((p = pfind(pid)) == NULL) { 526 if (proctree_locked) 527 sx_xunlock(&proctree_lock); 528 return (ESRCH); 529 } 530 } else { 531 /* this is slow, should be optimized */ 532 sx_slock(&allproc_lock); 533 FOREACH_PROC_IN_SYSTEM(p) { 534 PROC_LOCK(p); 535 mtx_lock_spin(&sched_lock); 536 FOREACH_THREAD_IN_PROC(p, td2) { 537 if (td2->td_tid == pid) 538 break; 539 } 540 mtx_unlock_spin(&sched_lock); 541 if (td2 != NULL) 542 break; /* proc lock held */ 543 PROC_UNLOCK(p); 544 } 545 sx_sunlock(&allproc_lock); 546 if (p == NULL) { 547 if (proctree_locked) 548 sx_xunlock(&proctree_lock); 549 return (ESRCH); 550 } 551 tid = pid; 552 pid = p->p_pid; 553 } 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 td2 = FIRST_THREAD_IN_PROC(p); 571 tid = td2->td_tid; 572 } 573 574 #ifdef COMPAT_IA32 575 /* 576 * Test if we're a 32 bit client and what the target is. 577 * Set the wrap controls accordingly. 578 */ 579 if (td->td_proc->p_sysent == &ia32_freebsd_sysvec) { 580 if (td2->td_proc->p_sysent == &ia32_freebsd_sysvec) 581 safe = 1; 582 wrap32 = 1; 583 } 584 #endif 585 /* 586 * Permissions check 587 */ 588 switch (req) { 589 case PT_TRACE_ME: 590 /* Always legal. */ 591 break; 592 593 case PT_ATTACH: 594 /* Self */ 595 if (p->p_pid == td->td_proc->p_pid) { 596 error = EINVAL; 597 goto fail; 598 } 599 600 /* Already traced */ 601 if (p->p_flag & P_TRACED) { 602 error = EBUSY; 603 goto fail; 604 } 605 606 /* Can't trace an ancestor if you're being traced. */ 607 if (curp->p_flag & P_TRACED) { 608 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 609 if (pp == p) { 610 error = EINVAL; 611 goto fail; 612 } 613 } 614 } 615 616 617 /* OK */ 618 break; 619 620 case PT_CLEARSTEP: 621 /* Allow thread to clear single step for itself */ 622 if (td->td_tid == tid) 623 break; 624 625 /* FALLTHROUGH */ 626 default: 627 /* not being traced... */ 628 if ((p->p_flag & P_TRACED) == 0) { 629 error = EPERM; 630 goto fail; 631 } 632 633 /* not being traced by YOU */ 634 if (p->p_pptr != td->td_proc) { 635 error = EBUSY; 636 goto fail; 637 } 638 639 /* not currently stopped */ 640 if (!P_SHOULDSTOP(p) || p->p_suspcount != p->p_numthreads || 641 (p->p_flag & P_WAITED) == 0) { 642 error = EBUSY; 643 goto fail; 644 } 645 646 /* OK */ 647 break; 648 } 649 650 #ifdef FIX_SSTEP 651 /* 652 * Single step fixup ala procfs 653 */ 654 FIX_SSTEP(td2); /* XXXKSE */ 655 #endif 656 657 /* 658 * Actually do the requests 659 */ 660 661 td->td_retval[0] = 0; 662 663 switch (req) { 664 case PT_TRACE_ME: 665 /* set my trace flag and "owner" so it can read/write me */ 666 p->p_flag |= P_TRACED; 667 p->p_oppid = p->p_pptr->p_pid; 668 PROC_UNLOCK(p); 669 sx_xunlock(&proctree_lock); 670 return (0); 671 672 case PT_ATTACH: 673 /* security check done above */ 674 p->p_flag |= P_TRACED; 675 p->p_oppid = p->p_pptr->p_pid; 676 if (p->p_pptr != td->td_proc) 677 proc_reparent(p, td->td_proc); 678 data = SIGSTOP; 679 goto sendsig; /* in PT_CONTINUE below */ 680 681 case PT_CLEARSTEP: 682 _PHOLD(p); 683 error = ptrace_clear_single_step(td2); 684 _PRELE(p); 685 if (error) 686 goto fail; 687 PROC_UNLOCK(p); 688 return (0); 689 690 case PT_SETSTEP: 691 _PHOLD(p); 692 error = ptrace_single_step(td2); 693 _PRELE(p); 694 if (error) 695 goto fail; 696 PROC_UNLOCK(p); 697 return (0); 698 699 case PT_SUSPEND: 700 _PHOLD(p); 701 mtx_lock_spin(&sched_lock); 702 td2->td_flags |= TDF_DBSUSPEND; 703 mtx_unlock_spin(&sched_lock); 704 _PRELE(p); 705 PROC_UNLOCK(p); 706 return (0); 707 708 case PT_RESUME: 709 _PHOLD(p); 710 mtx_lock_spin(&sched_lock); 711 td2->td_flags &= ~TDF_DBSUSPEND; 712 mtx_unlock_spin(&sched_lock); 713 _PRELE(p); 714 PROC_UNLOCK(p); 715 return (0); 716 717 case PT_STEP: 718 case PT_CONTINUE: 719 case PT_TO_SCE: 720 case PT_TO_SCX: 721 case PT_SYSCALL: 722 case PT_DETACH: 723 /* Zero means do not send any signal */ 724 if (data < 0 || data > _SIG_MAXSIG) { 725 error = EINVAL; 726 goto fail; 727 } 728 729 _PHOLD(p); 730 731 switch (req) { 732 case PT_STEP: 733 PROC_UNLOCK(p); 734 error = ptrace_single_step(td2); 735 if (error) { 736 PRELE(p); 737 goto fail_noproc; 738 } 739 PROC_LOCK(p); 740 break; 741 case PT_TO_SCE: 742 p->p_stops |= S_PT_SCE; 743 break; 744 case PT_TO_SCX: 745 p->p_stops |= S_PT_SCX; 746 break; 747 case PT_SYSCALL: 748 p->p_stops |= S_PT_SCE | S_PT_SCX; 749 break; 750 } 751 752 if (addr != (void *)1) { 753 PROC_UNLOCK(p); 754 error = ptrace_set_pc(td2, (u_long)(uintfptr_t)addr); 755 if (error) { 756 PRELE(p); 757 goto fail_noproc; 758 } 759 PROC_LOCK(p); 760 } 761 _PRELE(p); 762 763 if (req == PT_DETACH) { 764 /* reset process parent */ 765 if (p->p_oppid != p->p_pptr->p_pid) { 766 struct proc *pp; 767 768 PROC_UNLOCK(p); 769 pp = pfind(p->p_oppid); 770 if (pp == NULL) 771 pp = initproc; 772 else 773 PROC_UNLOCK(pp); 774 PROC_LOCK(p); 775 proc_reparent(p, pp); 776 if (pp == initproc) 777 p->p_sigparent = SIGCHLD; 778 } 779 p->p_flag &= ~(P_TRACED | P_WAITED); 780 p->p_oppid = 0; 781 782 /* should we send SIGCHLD? */ 783 } 784 785 sendsig: 786 if (proctree_locked) 787 sx_xunlock(&proctree_lock); 788 /* deliver or queue signal */ 789 if (P_SHOULDSTOP(p)) { 790 p->p_xstat = data; 791 mtx_lock_spin(&sched_lock); 792 if (saved_pid <= PID_MAX) { 793 p->p_xthread->td_flags &= ~TDF_XSIG; 794 p->p_xthread->td_xsig = data; 795 } else { 796 td2->td_flags &= ~TDF_XSIG; 797 td2->td_xsig = data; 798 } 799 p->p_xthread = NULL; 800 if (req == PT_DETACH) { 801 struct thread *td3; 802 FOREACH_THREAD_IN_PROC(p, td3) 803 td3->td_flags &= ~TDF_DBSUSPEND; 804 } 805 /* 806 * unsuspend all threads, to not let a thread run, 807 * you should use PT_SUSPEND to suspend it before 808 * continuing process. 809 */ 810 mtx_unlock_spin(&sched_lock); 811 thread_continued(p); 812 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG); 813 mtx_lock_spin(&sched_lock); 814 thread_unsuspend(p); 815 mtx_unlock_spin(&sched_lock); 816 } else if (data) { 817 psignal(p, data); 818 } 819 PROC_UNLOCK(p); 820 821 return (0); 822 823 case PT_WRITE_I: 824 case PT_WRITE_D: 825 write = 1; 826 /* FALLTHROUGH */ 827 case PT_READ_I: 828 case PT_READ_D: 829 PROC_UNLOCK(p); 830 tmp = 0; 831 /* write = 0 set above */ 832 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 833 iov.iov_len = sizeof(int); 834 uio.uio_iov = &iov; 835 uio.uio_iovcnt = 1; 836 uio.uio_offset = (off_t)(uintptr_t)addr; 837 uio.uio_resid = sizeof(int); 838 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */ 839 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 840 uio.uio_td = td; 841 error = proc_rwmem(p, &uio); 842 if (uio.uio_resid != 0) { 843 /* 844 * XXX proc_rwmem() doesn't currently return ENOSPC, 845 * so I think write() can bogusly return 0. 846 * XXX what happens for short writes? We don't want 847 * to write partial data. 848 * XXX proc_rwmem() returns EPERM for other invalid 849 * addresses. Convert this to EINVAL. Does this 850 * clobber returns of EPERM for other reasons? 851 */ 852 if (error == 0 || error == ENOSPC || error == EPERM) 853 error = EINVAL; /* EOF */ 854 } 855 if (!write) 856 td->td_retval[0] = tmp; 857 return (error); 858 859 case PT_IO: 860 PROC_UNLOCK(p); 861 #ifdef COMPAT_IA32 862 if (wrap32) { 863 piod32 = addr; 864 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; 865 iov.iov_len = piod32->piod_len; 866 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; 867 uio.uio_resid = piod32->piod_len; 868 } else 869 #endif 870 { 871 piod = addr; 872 iov.iov_base = piod->piod_addr; 873 iov.iov_len = piod->piod_len; 874 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 875 uio.uio_resid = piod->piod_len; 876 } 877 uio.uio_iov = &iov; 878 uio.uio_iovcnt = 1; 879 uio.uio_segflg = UIO_USERSPACE; 880 uio.uio_td = td; 881 #ifdef COMPAT_IA32 882 tmp = wrap32 ? piod32->piod_op : piod->piod_op; 883 #else 884 tmp = piod->piod_op; 885 #endif 886 switch (tmp) { 887 case PIOD_READ_D: 888 case PIOD_READ_I: 889 uio.uio_rw = UIO_READ; 890 break; 891 case PIOD_WRITE_D: 892 case PIOD_WRITE_I: 893 uio.uio_rw = UIO_WRITE; 894 break; 895 default: 896 return (EINVAL); 897 } 898 error = proc_rwmem(p, &uio); 899 #ifdef COMPAT_IA32 900 if (wrap32) 901 piod32->piod_len -= uio.uio_resid; 902 else 903 #endif 904 piod->piod_len -= uio.uio_resid; 905 return (error); 906 907 case PT_KILL: 908 data = SIGKILL; 909 goto sendsig; /* in PT_CONTINUE above */ 910 911 case PT_SETREGS: 912 _PHOLD(p); 913 error = PROC_WRITE(regs, td2, addr); 914 _PRELE(p); 915 PROC_UNLOCK(p); 916 return (error); 917 918 case PT_GETREGS: 919 _PHOLD(p); 920 error = PROC_READ(regs, td2, addr); 921 _PRELE(p); 922 PROC_UNLOCK(p); 923 return (error); 924 925 case PT_SETFPREGS: 926 _PHOLD(p); 927 error = PROC_WRITE(fpregs, td2, addr); 928 _PRELE(p); 929 PROC_UNLOCK(p); 930 return (error); 931 932 case PT_GETFPREGS: 933 _PHOLD(p); 934 error = PROC_READ(fpregs, td2, addr); 935 _PRELE(p); 936 PROC_UNLOCK(p); 937 return (error); 938 939 case PT_SETDBREGS: 940 _PHOLD(p); 941 error = PROC_WRITE(dbregs, td2, addr); 942 _PRELE(p); 943 PROC_UNLOCK(p); 944 return (error); 945 946 case PT_GETDBREGS: 947 _PHOLD(p); 948 error = PROC_READ(dbregs, td2, addr); 949 _PRELE(p); 950 PROC_UNLOCK(p); 951 return (error); 952 953 case PT_LWPINFO: 954 if (data == 0 || data > sizeof(*pl)) 955 return (EINVAL); 956 pl = addr; 957 _PHOLD(p); 958 if (saved_pid <= PID_MAX) { 959 pl->pl_lwpid = p->p_xthread->td_tid; 960 pl->pl_event = PL_EVENT_SIGNAL; 961 } else { 962 pl->pl_lwpid = td2->td_tid; 963 if (td2->td_flags & TDF_XSIG) 964 pl->pl_event = PL_EVENT_SIGNAL; 965 else 966 pl->pl_event = 0; 967 } 968 if (td2->td_pflags & TDP_SA) { 969 pl->pl_flags = PL_FLAG_SA; 970 if (td2->td_upcall && !TD_CAN_UNBIND(td2)) 971 pl->pl_flags |= PL_FLAG_BOUND; 972 } else { 973 pl->pl_flags = 0; 974 } 975 _PRELE(p); 976 PROC_UNLOCK(p); 977 return (0); 978 979 case PT_GETNUMLWPS: 980 td->td_retval[0] = p->p_numthreads; 981 PROC_UNLOCK(p); 982 return (0); 983 984 case PT_GETLWPLIST: 985 if (data <= 0) { 986 PROC_UNLOCK(p); 987 return (EINVAL); 988 } 989 num = imin(p->p_numthreads, data); 990 PROC_UNLOCK(p); 991 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 992 tmp = 0; 993 PROC_LOCK(p); 994 mtx_lock_spin(&sched_lock); 995 FOREACH_THREAD_IN_PROC(p, td2) { 996 if (tmp >= num) 997 break; 998 buf[tmp++] = td2->td_tid; 999 } 1000 mtx_unlock_spin(&sched_lock); 1001 PROC_UNLOCK(p); 1002 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 1003 free(buf, M_TEMP); 1004 if (!error) 1005 td->td_retval[0] = num; 1006 return (error); 1007 1008 default: 1009 #ifdef __HAVE_PTRACE_MACHDEP 1010 if (req >= PT_FIRSTMACH) { 1011 _PHOLD(p); 1012 PROC_UNLOCK(p); 1013 error = cpu_ptrace(td2, req, addr, data); 1014 PRELE(p); 1015 return (error); 1016 } 1017 #endif 1018 break; 1019 } 1020 1021 /* Unknown request. */ 1022 error = EINVAL; 1023 1024 fail: 1025 PROC_UNLOCK(p); 1026 fail_noproc: 1027 if (proctree_locked) 1028 sx_xunlock(&proctree_lock); 1029 return (error); 1030 } 1031 #undef PROC_READ 1032 #undef PROC_WRITE 1033 1034 /* 1035 * Stop a process because of a debugging event; 1036 * stay stopped until p->p_step is cleared 1037 * (cleared by PIOCCONT in procfs). 1038 */ 1039 void 1040 stopevent(struct proc *p, unsigned int event, unsigned int val) 1041 { 1042 1043 PROC_LOCK_ASSERT(p, MA_OWNED); 1044 p->p_step = 1; 1045 do { 1046 p->p_xstat = val; 1047 p->p_xthread = NULL; 1048 p->p_stype = event; /* Which event caused the stop? */ 1049 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ 1050 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); 1051 } while (p->p_step); 1052 } 1053