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/sysent.h> 43 #include <sys/sysproto.h> 44 #include <sys/proc.h> 45 #include <sys/vnode.h> 46 #include <sys/ptrace.h> 47 #include <sys/sx.h> 48 #include <sys/malloc.h> 49 #include <sys/signalvar.h> 50 51 #include <machine/reg.h> 52 53 #include <security/audit/audit.h> 54 55 #include <vm/vm.h> 56 #include <vm/pmap.h> 57 #include <vm/vm_extern.h> 58 #include <vm/vm_map.h> 59 #include <vm/vm_kern.h> 60 #include <vm/vm_object.h> 61 #include <vm/vm_page.h> 62 #include <vm/vm_pager.h> 63 #include <vm/vm_param.h> 64 65 #ifdef COMPAT_FREEBSD32 66 #include <sys/procfs.h> 67 #include <compat/freebsd32/freebsd32_signal.h> 68 69 struct ptrace_io_desc32 { 70 int piod_op; 71 uint32_t piod_offs; 72 uint32_t piod_addr; 73 uint32_t piod_len; 74 }; 75 76 struct ptrace_vm_entry32 { 77 int pve_entry; 78 int pve_timestamp; 79 uint32_t pve_start; 80 uint32_t pve_end; 81 uint32_t pve_offset; 82 u_int pve_prot; 83 u_int pve_pathlen; 84 int32_t pve_fileid; 85 u_int pve_fsid; 86 uint32_t pve_path; 87 }; 88 89 struct ptrace_lwpinfo32 { 90 lwpid_t pl_lwpid; /* LWP described. */ 91 int pl_event; /* Event that stopped the LWP. */ 92 int pl_flags; /* LWP flags. */ 93 sigset_t pl_sigmask; /* LWP signal mask */ 94 sigset_t pl_siglist; /* LWP pending signal */ 95 struct siginfo32 pl_siginfo; /* siginfo for signal */ 96 char pl_tdname[MAXCOMLEN + 1]; /* LWP name. */ 97 int pl_child_pid; /* New child pid */ 98 }; 99 100 #endif 101 102 /* 103 * Functions implemented using PROC_ACTION(): 104 * 105 * proc_read_regs(proc, regs) 106 * Get the current user-visible register set from the process 107 * and copy it into the regs structure (<machine/reg.h>). 108 * The process is stopped at the time read_regs is called. 109 * 110 * proc_write_regs(proc, regs) 111 * Update the current register set from the passed in regs 112 * structure. Take care to avoid clobbering special CPU 113 * registers or privileged bits in the PSL. 114 * Depending on the architecture this may have fix-up work to do, 115 * especially if the IAR or PCW are modified. 116 * The process is stopped at the time write_regs is called. 117 * 118 * proc_read_fpregs, proc_write_fpregs 119 * deal with the floating point register set, otherwise as above. 120 * 121 * proc_read_dbregs, proc_write_dbregs 122 * deal with the processor debug register set, otherwise as above. 123 * 124 * proc_sstep(proc) 125 * Arrange for the process to trap after executing a single instruction. 126 */ 127 128 #define PROC_ACTION(action) do { \ 129 int error; \ 130 \ 131 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ 132 if ((td->td_proc->p_flag & P_INMEM) == 0) \ 133 error = EIO; \ 134 else \ 135 error = (action); \ 136 return (error); \ 137 } while(0) 138 139 int 140 proc_read_regs(struct thread *td, struct reg *regs) 141 { 142 143 PROC_ACTION(fill_regs(td, regs)); 144 } 145 146 int 147 proc_write_regs(struct thread *td, struct reg *regs) 148 { 149 150 PROC_ACTION(set_regs(td, regs)); 151 } 152 153 int 154 proc_read_dbregs(struct thread *td, struct dbreg *dbregs) 155 { 156 157 PROC_ACTION(fill_dbregs(td, dbregs)); 158 } 159 160 int 161 proc_write_dbregs(struct thread *td, struct dbreg *dbregs) 162 { 163 164 PROC_ACTION(set_dbregs(td, dbregs)); 165 } 166 167 /* 168 * Ptrace doesn't support fpregs at all, and there are no security holes 169 * or translations for fpregs, so we can just copy them. 170 */ 171 int 172 proc_read_fpregs(struct thread *td, struct fpreg *fpregs) 173 { 174 175 PROC_ACTION(fill_fpregs(td, fpregs)); 176 } 177 178 int 179 proc_write_fpregs(struct thread *td, struct fpreg *fpregs) 180 { 181 182 PROC_ACTION(set_fpregs(td, fpregs)); 183 } 184 185 #ifdef COMPAT_FREEBSD32 186 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 187 int 188 proc_read_regs32(struct thread *td, struct reg32 *regs32) 189 { 190 191 PROC_ACTION(fill_regs32(td, regs32)); 192 } 193 194 int 195 proc_write_regs32(struct thread *td, struct reg32 *regs32) 196 { 197 198 PROC_ACTION(set_regs32(td, regs32)); 199 } 200 201 int 202 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 203 { 204 205 PROC_ACTION(fill_dbregs32(td, dbregs32)); 206 } 207 208 int 209 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 210 { 211 212 PROC_ACTION(set_dbregs32(td, dbregs32)); 213 } 214 215 int 216 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 217 { 218 219 PROC_ACTION(fill_fpregs32(td, fpregs32)); 220 } 221 222 int 223 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 224 { 225 226 PROC_ACTION(set_fpregs32(td, fpregs32)); 227 } 228 #endif 229 230 int 231 proc_sstep(struct thread *td) 232 { 233 234 PROC_ACTION(ptrace_single_step(td)); 235 } 236 237 int 238 proc_rwmem(struct proc *p, struct uio *uio) 239 { 240 vm_map_t map; 241 vm_offset_t pageno; /* page number */ 242 vm_prot_t reqprot; 243 int error, fault_flags, page_offset, writing; 244 245 /* 246 * Assert that someone has locked this vmspace. (Should be 247 * curthread but we can't assert that.) This keeps the process 248 * from exiting out from under us until this operation completes. 249 */ 250 KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__, 251 p, p->p_pid)); 252 253 /* 254 * The map we want... 255 */ 256 map = &p->p_vmspace->vm_map; 257 258 /* 259 * If we are writing, then we request vm_fault() to create a private 260 * copy of each page. Since these copies will not be writeable by the 261 * process, we must explicity request that they be dirtied. 262 */ 263 writing = uio->uio_rw == UIO_WRITE; 264 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ; 265 fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 266 267 /* 268 * Only map in one page at a time. We don't have to, but it 269 * makes things easier. This way is trivial - right? 270 */ 271 do { 272 vm_offset_t uva; 273 u_int len; 274 vm_page_t m; 275 276 uva = (vm_offset_t)uio->uio_offset; 277 278 /* 279 * Get the page number of this segment. 280 */ 281 pageno = trunc_page(uva); 282 page_offset = uva - pageno; 283 284 /* 285 * How many bytes to copy 286 */ 287 len = min(PAGE_SIZE - page_offset, uio->uio_resid); 288 289 /* 290 * Fault and hold the page on behalf of the process. 291 */ 292 error = vm_fault_hold(map, pageno, reqprot, fault_flags, &m); 293 if (error != KERN_SUCCESS) { 294 if (error == KERN_RESOURCE_SHORTAGE) 295 error = ENOMEM; 296 else 297 error = EFAULT; 298 break; 299 } 300 301 /* 302 * Now do the i/o move. 303 */ 304 error = uiomove_fromphys(&m, page_offset, len, uio); 305 306 /* Make the I-cache coherent for breakpoints. */ 307 if (writing && error == 0) { 308 vm_map_lock_read(map); 309 if (vm_map_check_protection(map, pageno, pageno + 310 PAGE_SIZE, VM_PROT_EXECUTE)) 311 vm_sync_icache(map, uva, len); 312 vm_map_unlock_read(map); 313 } 314 315 /* 316 * Release the page. 317 */ 318 vm_page_lock(m); 319 vm_page_unhold(m); 320 vm_page_unlock(m); 321 322 } while (error == 0 && uio->uio_resid > 0); 323 324 return (error); 325 } 326 327 static int 328 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve) 329 { 330 struct vattr vattr; 331 vm_map_t map; 332 vm_map_entry_t entry; 333 vm_object_t obj, tobj, lobj; 334 struct vmspace *vm; 335 struct vnode *vp; 336 char *freepath, *fullpath; 337 u_int pathlen; 338 int error, index, vfslocked; 339 340 error = 0; 341 obj = NULL; 342 343 vm = vmspace_acquire_ref(p); 344 map = &vm->vm_map; 345 vm_map_lock_read(map); 346 347 do { 348 entry = map->header.next; 349 index = 0; 350 while (index < pve->pve_entry && entry != &map->header) { 351 entry = entry->next; 352 index++; 353 } 354 if (index != pve->pve_entry) { 355 error = EINVAL; 356 break; 357 } 358 while (entry != &map->header && 359 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) { 360 entry = entry->next; 361 index++; 362 } 363 if (entry == &map->header) { 364 error = ENOENT; 365 break; 366 } 367 368 /* We got an entry. */ 369 pve->pve_entry = index + 1; 370 pve->pve_timestamp = map->timestamp; 371 pve->pve_start = entry->start; 372 pve->pve_end = entry->end - 1; 373 pve->pve_offset = entry->offset; 374 pve->pve_prot = entry->protection; 375 376 /* Backing object's path needed? */ 377 if (pve->pve_pathlen == 0) 378 break; 379 380 pathlen = pve->pve_pathlen; 381 pve->pve_pathlen = 0; 382 383 obj = entry->object.vm_object; 384 if (obj != NULL) 385 VM_OBJECT_LOCK(obj); 386 } while (0); 387 388 vm_map_unlock_read(map); 389 vmspace_free(vm); 390 391 pve->pve_fsid = VNOVAL; 392 pve->pve_fileid = VNOVAL; 393 394 if (error == 0 && obj != NULL) { 395 lobj = obj; 396 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 397 if (tobj != obj) 398 VM_OBJECT_LOCK(tobj); 399 if (lobj != obj) 400 VM_OBJECT_UNLOCK(lobj); 401 lobj = tobj; 402 pve->pve_offset += tobj->backing_object_offset; 403 } 404 vp = (lobj->type == OBJT_VNODE) ? lobj->handle : NULL; 405 if (vp != NULL) 406 vref(vp); 407 if (lobj != obj) 408 VM_OBJECT_UNLOCK(lobj); 409 VM_OBJECT_UNLOCK(obj); 410 411 if (vp != NULL) { 412 freepath = NULL; 413 fullpath = NULL; 414 vn_fullpath(td, vp, &fullpath, &freepath); 415 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 416 vn_lock(vp, LK_SHARED | LK_RETRY); 417 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) { 418 pve->pve_fileid = vattr.va_fileid; 419 pve->pve_fsid = vattr.va_fsid; 420 } 421 vput(vp); 422 VFS_UNLOCK_GIANT(vfslocked); 423 424 if (fullpath != NULL) { 425 pve->pve_pathlen = strlen(fullpath) + 1; 426 if (pve->pve_pathlen <= pathlen) { 427 error = copyout(fullpath, pve->pve_path, 428 pve->pve_pathlen); 429 } else 430 error = ENAMETOOLONG; 431 } 432 if (freepath != NULL) 433 free(freepath, M_TEMP); 434 } 435 } 436 437 return (error); 438 } 439 440 #ifdef COMPAT_FREEBSD32 441 static int 442 ptrace_vm_entry32(struct thread *td, struct proc *p, 443 struct ptrace_vm_entry32 *pve32) 444 { 445 struct ptrace_vm_entry pve; 446 int error; 447 448 pve.pve_entry = pve32->pve_entry; 449 pve.pve_pathlen = pve32->pve_pathlen; 450 pve.pve_path = (void *)(uintptr_t)pve32->pve_path; 451 452 error = ptrace_vm_entry(td, p, &pve); 453 if (error == 0) { 454 pve32->pve_entry = pve.pve_entry; 455 pve32->pve_timestamp = pve.pve_timestamp; 456 pve32->pve_start = pve.pve_start; 457 pve32->pve_end = pve.pve_end; 458 pve32->pve_offset = pve.pve_offset; 459 pve32->pve_prot = pve.pve_prot; 460 pve32->pve_fileid = pve.pve_fileid; 461 pve32->pve_fsid = pve.pve_fsid; 462 } 463 464 pve32->pve_pathlen = pve.pve_pathlen; 465 return (error); 466 } 467 468 static void 469 ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl, 470 struct ptrace_lwpinfo32 *pl32) 471 { 472 473 pl32->pl_lwpid = pl->pl_lwpid; 474 pl32->pl_event = pl->pl_event; 475 pl32->pl_flags = pl->pl_flags; 476 pl32->pl_sigmask = pl->pl_sigmask; 477 pl32->pl_siglist = pl->pl_siglist; 478 siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo); 479 strcpy(pl32->pl_tdname, pl->pl_tdname); 480 pl32->pl_child_pid = pl->pl_child_pid; 481 } 482 #endif /* COMPAT_FREEBSD32 */ 483 484 /* 485 * Process debugging system call. 486 */ 487 #ifndef _SYS_SYSPROTO_H_ 488 struct ptrace_args { 489 int req; 490 pid_t pid; 491 caddr_t addr; 492 int data; 493 }; 494 #endif 495 496 #ifdef COMPAT_FREEBSD32 497 /* 498 * This CPP subterfuge is to try and reduce the number of ifdefs in 499 * the body of the code. 500 * COPYIN(uap->addr, &r.reg, sizeof r.reg); 501 * becomes either: 502 * copyin(uap->addr, &r.reg, sizeof r.reg); 503 * or 504 * copyin(uap->addr, &r.reg32, sizeof r.reg32); 505 * .. except this is done at runtime. 506 */ 507 #define COPYIN(u, k, s) wrap32 ? \ 508 copyin(u, k ## 32, s ## 32) : \ 509 copyin(u, k, s) 510 #define COPYOUT(k, u, s) wrap32 ? \ 511 copyout(k ## 32, u, s ## 32) : \ 512 copyout(k, u, s) 513 #else 514 #define COPYIN(u, k, s) copyin(u, k, s) 515 #define COPYOUT(k, u, s) copyout(k, u, s) 516 #endif 517 int 518 ptrace(struct thread *td, struct ptrace_args *uap) 519 { 520 /* 521 * XXX this obfuscation is to reduce stack usage, but the register 522 * structs may be too large to put on the stack anyway. 523 */ 524 union { 525 struct ptrace_io_desc piod; 526 struct ptrace_lwpinfo pl; 527 struct ptrace_vm_entry pve; 528 struct dbreg dbreg; 529 struct fpreg fpreg; 530 struct reg reg; 531 #ifdef COMPAT_FREEBSD32 532 struct dbreg32 dbreg32; 533 struct fpreg32 fpreg32; 534 struct reg32 reg32; 535 struct ptrace_io_desc32 piod32; 536 struct ptrace_lwpinfo32 pl32; 537 struct ptrace_vm_entry32 pve32; 538 #endif 539 } r; 540 void *addr; 541 int error = 0; 542 #ifdef COMPAT_FREEBSD32 543 int wrap32 = 0; 544 545 if (SV_CURPROC_FLAG(SV_ILP32)) 546 wrap32 = 1; 547 #endif 548 AUDIT_ARG_PID(uap->pid); 549 AUDIT_ARG_CMD(uap->req); 550 AUDIT_ARG_VALUE(uap->data); 551 addr = &r; 552 switch (uap->req) { 553 case PT_GETREGS: 554 case PT_GETFPREGS: 555 case PT_GETDBREGS: 556 case PT_LWPINFO: 557 break; 558 case PT_SETREGS: 559 error = COPYIN(uap->addr, &r.reg, sizeof r.reg); 560 break; 561 case PT_SETFPREGS: 562 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); 563 break; 564 case PT_SETDBREGS: 565 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); 566 break; 567 case PT_IO: 568 error = COPYIN(uap->addr, &r.piod, sizeof r.piod); 569 break; 570 case PT_VM_ENTRY: 571 error = COPYIN(uap->addr, &r.pve, sizeof r.pve); 572 break; 573 default: 574 addr = uap->addr; 575 break; 576 } 577 if (error) 578 return (error); 579 580 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 581 if (error) 582 return (error); 583 584 switch (uap->req) { 585 case PT_VM_ENTRY: 586 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve); 587 break; 588 case PT_IO: 589 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); 590 break; 591 case PT_GETREGS: 592 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); 593 break; 594 case PT_GETFPREGS: 595 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); 596 break; 597 case PT_GETDBREGS: 598 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); 599 break; 600 case PT_LWPINFO: 601 error = copyout(&r.pl, uap->addr, uap->data); 602 break; 603 } 604 605 return (error); 606 } 607 #undef COPYIN 608 #undef COPYOUT 609 610 #ifdef COMPAT_FREEBSD32 611 /* 612 * PROC_READ(regs, td2, addr); 613 * becomes either: 614 * proc_read_regs(td2, addr); 615 * or 616 * proc_read_regs32(td2, addr); 617 * .. except this is done at runtime. There is an additional 618 * complication in that PROC_WRITE disallows 32 bit consumers 619 * from writing to 64 bit address space targets. 620 */ 621 #define PROC_READ(w, t, a) wrap32 ? \ 622 proc_read_ ## w ## 32(t, a) : \ 623 proc_read_ ## w (t, a) 624 #define PROC_WRITE(w, t, a) wrap32 ? \ 625 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 626 proc_write_ ## w (t, a) 627 #else 628 #define PROC_READ(w, t, a) proc_read_ ## w (t, a) 629 #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 630 #endif 631 632 int 633 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 634 { 635 struct iovec iov; 636 struct uio uio; 637 struct proc *curp, *p, *pp; 638 struct thread *td2 = NULL; 639 struct ptrace_io_desc *piod = NULL; 640 struct ptrace_lwpinfo *pl; 641 int error, write, tmp, num; 642 int proctree_locked = 0; 643 lwpid_t tid = 0, *buf; 644 #ifdef COMPAT_FREEBSD32 645 int wrap32 = 0, safe = 0; 646 struct ptrace_io_desc32 *piod32 = NULL; 647 struct ptrace_lwpinfo32 *pl32 = NULL; 648 struct ptrace_lwpinfo plr; 649 #endif 650 651 curp = td->td_proc; 652 653 /* Lock proctree before locking the process. */ 654 switch (req) { 655 case PT_TRACE_ME: 656 case PT_ATTACH: 657 case PT_STEP: 658 case PT_CONTINUE: 659 case PT_TO_SCE: 660 case PT_TO_SCX: 661 case PT_SYSCALL: 662 case PT_FOLLOW_FORK: 663 case PT_DETACH: 664 sx_xlock(&proctree_lock); 665 proctree_locked = 1; 666 break; 667 default: 668 break; 669 } 670 671 write = 0; 672 if (req == PT_TRACE_ME) { 673 p = td->td_proc; 674 PROC_LOCK(p); 675 } else { 676 if (pid <= PID_MAX) { 677 if ((p = pfind(pid)) == NULL) { 678 if (proctree_locked) 679 sx_xunlock(&proctree_lock); 680 return (ESRCH); 681 } 682 } else { 683 td2 = tdfind(pid, -1); 684 if (td2 == NULL) { 685 if (proctree_locked) 686 sx_xunlock(&proctree_lock); 687 return (ESRCH); 688 } 689 p = td2->td_proc; 690 tid = pid; 691 pid = p->p_pid; 692 } 693 } 694 AUDIT_ARG_PROCESS(p); 695 696 if ((p->p_flag & P_WEXIT) != 0) { 697 error = ESRCH; 698 goto fail; 699 } 700 if ((error = p_cansee(td, p)) != 0) 701 goto fail; 702 703 if ((error = p_candebug(td, p)) != 0) 704 goto fail; 705 706 /* 707 * System processes can't be debugged. 708 */ 709 if ((p->p_flag & P_SYSTEM) != 0) { 710 error = EINVAL; 711 goto fail; 712 } 713 714 if (tid == 0) { 715 if ((p->p_flag & P_STOPPED_TRACE) != 0) { 716 KASSERT(p->p_xthread != NULL, ("NULL p_xthread")); 717 td2 = p->p_xthread; 718 } else { 719 td2 = FIRST_THREAD_IN_PROC(p); 720 } 721 tid = td2->td_tid; 722 } 723 724 #ifdef COMPAT_FREEBSD32 725 /* 726 * Test if we're a 32 bit client and what the target is. 727 * Set the wrap controls accordingly. 728 */ 729 if (SV_CURPROC_FLAG(SV_ILP32)) { 730 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32)) 731 safe = 1; 732 wrap32 = 1; 733 } 734 #endif 735 /* 736 * Permissions check 737 */ 738 switch (req) { 739 case PT_TRACE_ME: 740 /* Always legal. */ 741 break; 742 743 case PT_ATTACH: 744 /* Self */ 745 if (p->p_pid == td->td_proc->p_pid) { 746 error = EINVAL; 747 goto fail; 748 } 749 750 /* Already traced */ 751 if (p->p_flag & P_TRACED) { 752 error = EBUSY; 753 goto fail; 754 } 755 756 /* Can't trace an ancestor if you're being traced. */ 757 if (curp->p_flag & P_TRACED) { 758 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 759 if (pp == p) { 760 error = EINVAL; 761 goto fail; 762 } 763 } 764 } 765 766 767 /* OK */ 768 break; 769 770 case PT_CLEARSTEP: 771 /* Allow thread to clear single step for itself */ 772 if (td->td_tid == tid) 773 break; 774 775 /* FALLTHROUGH */ 776 default: 777 /* not being traced... */ 778 if ((p->p_flag & P_TRACED) == 0) { 779 error = EPERM; 780 goto fail; 781 } 782 783 /* not being traced by YOU */ 784 if (p->p_pptr != td->td_proc) { 785 error = EBUSY; 786 goto fail; 787 } 788 789 /* not currently stopped */ 790 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 || 791 p->p_suspcount != p->p_numthreads || 792 (p->p_flag & P_WAITED) == 0) { 793 error = EBUSY; 794 goto fail; 795 } 796 797 if ((p->p_flag & P_STOPPED_TRACE) == 0) { 798 static int count = 0; 799 if (count++ == 0) 800 printf("P_STOPPED_TRACE not set.\n"); 801 } 802 803 /* OK */ 804 break; 805 } 806 807 /* Keep this process around until we finish this request. */ 808 _PHOLD(p); 809 810 #ifdef FIX_SSTEP 811 /* 812 * Single step fixup ala procfs 813 */ 814 FIX_SSTEP(td2); 815 #endif 816 817 /* 818 * Actually do the requests 819 */ 820 821 td->td_retval[0] = 0; 822 823 switch (req) { 824 case PT_TRACE_ME: 825 /* set my trace flag and "owner" so it can read/write me */ 826 p->p_flag |= P_TRACED; 827 p->p_oppid = p->p_pptr->p_pid; 828 break; 829 830 case PT_ATTACH: 831 /* security check done above */ 832 p->p_flag |= P_TRACED; 833 p->p_oppid = p->p_pptr->p_pid; 834 if (p->p_pptr != td->td_proc) 835 proc_reparent(p, td->td_proc); 836 data = SIGSTOP; 837 goto sendsig; /* in PT_CONTINUE below */ 838 839 case PT_CLEARSTEP: 840 error = ptrace_clear_single_step(td2); 841 break; 842 843 case PT_SETSTEP: 844 error = ptrace_single_step(td2); 845 break; 846 847 case PT_SUSPEND: 848 td2->td_dbgflags |= TDB_SUSPEND; 849 thread_lock(td2); 850 td2->td_flags |= TDF_NEEDSUSPCHK; 851 thread_unlock(td2); 852 break; 853 854 case PT_RESUME: 855 td2->td_dbgflags &= ~TDB_SUSPEND; 856 break; 857 858 case PT_FOLLOW_FORK: 859 if (data) 860 p->p_flag |= P_FOLLOWFORK; 861 else 862 p->p_flag &= ~P_FOLLOWFORK; 863 break; 864 865 case PT_STEP: 866 case PT_CONTINUE: 867 case PT_TO_SCE: 868 case PT_TO_SCX: 869 case PT_SYSCALL: 870 case PT_DETACH: 871 /* Zero means do not send any signal */ 872 if (data < 0 || data > _SIG_MAXSIG) { 873 error = EINVAL; 874 break; 875 } 876 877 switch (req) { 878 case PT_STEP: 879 error = ptrace_single_step(td2); 880 if (error) 881 goto out; 882 break; 883 case PT_CONTINUE: 884 case PT_TO_SCE: 885 case PT_TO_SCX: 886 case PT_SYSCALL: 887 if (addr != (void *)1) { 888 error = ptrace_set_pc(td2, 889 (u_long)(uintfptr_t)addr); 890 if (error) 891 goto out; 892 } 893 switch (req) { 894 case PT_TO_SCE: 895 p->p_stops |= S_PT_SCE; 896 break; 897 case PT_TO_SCX: 898 p->p_stops |= S_PT_SCX; 899 break; 900 case PT_SYSCALL: 901 p->p_stops |= S_PT_SCE | S_PT_SCX; 902 break; 903 } 904 break; 905 case PT_DETACH: 906 /* reset process parent */ 907 if (p->p_oppid != p->p_pptr->p_pid) { 908 struct proc *pp; 909 910 PROC_LOCK(p->p_pptr); 911 sigqueue_take(p->p_ksi); 912 PROC_UNLOCK(p->p_pptr); 913 914 PROC_UNLOCK(p); 915 pp = pfind(p->p_oppid); 916 if (pp == NULL) 917 pp = initproc; 918 else 919 PROC_UNLOCK(pp); 920 PROC_LOCK(p); 921 proc_reparent(p, pp); 922 if (pp == initproc) 923 p->p_sigparent = SIGCHLD; 924 } 925 p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK); 926 p->p_oppid = 0; 927 928 /* should we send SIGCHLD? */ 929 /* childproc_continued(p); */ 930 break; 931 } 932 933 sendsig: 934 if (proctree_locked) { 935 sx_xunlock(&proctree_lock); 936 proctree_locked = 0; 937 } 938 p->p_xstat = data; 939 p->p_xthread = NULL; 940 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) { 941 /* deliver or queue signal */ 942 td2->td_dbgflags &= ~TDB_XSIG; 943 td2->td_xsig = data; 944 945 if (req == PT_DETACH) { 946 struct thread *td3; 947 FOREACH_THREAD_IN_PROC(p, td3) { 948 td3->td_dbgflags &= ~TDB_SUSPEND; 949 } 950 } 951 /* 952 * unsuspend all threads, to not let a thread run, 953 * you should use PT_SUSPEND to suspend it before 954 * continuing process. 955 */ 956 PROC_SLOCK(p); 957 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED); 958 thread_unsuspend(p); 959 PROC_SUNLOCK(p); 960 } else { 961 if (data) 962 psignal(p, data); 963 } 964 break; 965 966 case PT_WRITE_I: 967 case PT_WRITE_D: 968 td2->td_dbgflags |= TDB_USERWR; 969 write = 1; 970 /* FALLTHROUGH */ 971 case PT_READ_I: 972 case PT_READ_D: 973 PROC_UNLOCK(p); 974 tmp = 0; 975 /* write = 0 set above */ 976 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 977 iov.iov_len = sizeof(int); 978 uio.uio_iov = &iov; 979 uio.uio_iovcnt = 1; 980 uio.uio_offset = (off_t)(uintptr_t)addr; 981 uio.uio_resid = sizeof(int); 982 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */ 983 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 984 uio.uio_td = td; 985 error = proc_rwmem(p, &uio); 986 if (uio.uio_resid != 0) { 987 /* 988 * XXX proc_rwmem() doesn't currently return ENOSPC, 989 * so I think write() can bogusly return 0. 990 * XXX what happens for short writes? We don't want 991 * to write partial data. 992 * XXX proc_rwmem() returns EPERM for other invalid 993 * addresses. Convert this to EINVAL. Does this 994 * clobber returns of EPERM for other reasons? 995 */ 996 if (error == 0 || error == ENOSPC || error == EPERM) 997 error = EINVAL; /* EOF */ 998 } 999 if (!write) 1000 td->td_retval[0] = tmp; 1001 PROC_LOCK(p); 1002 break; 1003 1004 case PT_IO: 1005 #ifdef COMPAT_FREEBSD32 1006 if (wrap32) { 1007 piod32 = addr; 1008 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; 1009 iov.iov_len = piod32->piod_len; 1010 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; 1011 uio.uio_resid = piod32->piod_len; 1012 } else 1013 #endif 1014 { 1015 piod = addr; 1016 iov.iov_base = piod->piod_addr; 1017 iov.iov_len = piod->piod_len; 1018 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 1019 uio.uio_resid = piod->piod_len; 1020 } 1021 uio.uio_iov = &iov; 1022 uio.uio_iovcnt = 1; 1023 uio.uio_segflg = UIO_USERSPACE; 1024 uio.uio_td = td; 1025 #ifdef COMPAT_FREEBSD32 1026 tmp = wrap32 ? piod32->piod_op : piod->piod_op; 1027 #else 1028 tmp = piod->piod_op; 1029 #endif 1030 switch (tmp) { 1031 case PIOD_READ_D: 1032 case PIOD_READ_I: 1033 uio.uio_rw = UIO_READ; 1034 break; 1035 case PIOD_WRITE_D: 1036 case PIOD_WRITE_I: 1037 td2->td_dbgflags |= TDB_USERWR; 1038 uio.uio_rw = UIO_WRITE; 1039 break; 1040 default: 1041 error = EINVAL; 1042 goto out; 1043 } 1044 PROC_UNLOCK(p); 1045 error = proc_rwmem(p, &uio); 1046 #ifdef COMPAT_FREEBSD32 1047 if (wrap32) 1048 piod32->piod_len -= uio.uio_resid; 1049 else 1050 #endif 1051 piod->piod_len -= uio.uio_resid; 1052 PROC_LOCK(p); 1053 break; 1054 1055 case PT_KILL: 1056 data = SIGKILL; 1057 goto sendsig; /* in PT_CONTINUE above */ 1058 1059 case PT_SETREGS: 1060 td2->td_dbgflags |= TDB_USERWR; 1061 error = PROC_WRITE(regs, td2, addr); 1062 break; 1063 1064 case PT_GETREGS: 1065 error = PROC_READ(regs, td2, addr); 1066 break; 1067 1068 case PT_SETFPREGS: 1069 td2->td_dbgflags |= TDB_USERWR; 1070 error = PROC_WRITE(fpregs, td2, addr); 1071 break; 1072 1073 case PT_GETFPREGS: 1074 error = PROC_READ(fpregs, td2, addr); 1075 break; 1076 1077 case PT_SETDBREGS: 1078 td2->td_dbgflags |= TDB_USERWR; 1079 error = PROC_WRITE(dbregs, td2, addr); 1080 break; 1081 1082 case PT_GETDBREGS: 1083 error = PROC_READ(dbregs, td2, addr); 1084 break; 1085 1086 case PT_LWPINFO: 1087 if (data <= 0 || 1088 #ifdef COMPAT_FREEBSD32 1089 (!wrap32 && data > sizeof(*pl)) || 1090 (wrap32 && data > sizeof(*pl32))) { 1091 #else 1092 data > sizeof(*pl)) { 1093 #endif 1094 error = EINVAL; 1095 break; 1096 } 1097 #ifdef COMPAT_FREEBSD32 1098 if (wrap32) { 1099 pl = &plr; 1100 pl32 = addr; 1101 } else 1102 #endif 1103 pl = addr; 1104 pl->pl_lwpid = td2->td_tid; 1105 pl->pl_flags = 0; 1106 if (td2->td_dbgflags & TDB_XSIG) { 1107 pl->pl_event = PL_EVENT_SIGNAL; 1108 if (td2->td_dbgksi.ksi_signo != 0 && 1109 #ifdef COMPAT_FREEBSD32 1110 ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo, 1111 pl_siginfo) + sizeof(pl->pl_siginfo)) || 1112 (wrap32 && data >= offsetof(struct ptrace_lwpinfo32, 1113 pl_siginfo) + sizeof(struct siginfo32))) 1114 #else 1115 data >= offsetof(struct ptrace_lwpinfo, pl_siginfo) 1116 + sizeof(pl->pl_siginfo) 1117 #endif 1118 ){ 1119 pl->pl_flags |= PL_FLAG_SI; 1120 pl->pl_siginfo = td2->td_dbgksi.ksi_info; 1121 } 1122 } 1123 if ((pl->pl_flags & PL_FLAG_SI) == 0) 1124 bzero(&pl->pl_siginfo, sizeof(pl->pl_siginfo)); 1125 if (td2->td_dbgflags & TDB_SCE) 1126 pl->pl_flags |= PL_FLAG_SCE; 1127 else if (td2->td_dbgflags & TDB_SCX) 1128 pl->pl_flags |= PL_FLAG_SCX; 1129 if (td2->td_dbgflags & TDB_EXEC) 1130 pl->pl_flags |= PL_FLAG_EXEC; 1131 if (td2->td_dbgflags & TDB_FORK) { 1132 pl->pl_flags |= PL_FLAG_FORKED; 1133 pl->pl_child_pid = td2->td_dbg_forked; 1134 } 1135 pl->pl_sigmask = td2->td_sigmask; 1136 pl->pl_siglist = td2->td_siglist; 1137 strcpy(pl->pl_tdname, td2->td_name); 1138 #ifdef COMPAT_FREEBSD32 1139 if (wrap32) 1140 ptrace_lwpinfo_to32(pl, pl32); 1141 #endif 1142 break; 1143 1144 case PT_GETNUMLWPS: 1145 td->td_retval[0] = p->p_numthreads; 1146 break; 1147 1148 case PT_GETLWPLIST: 1149 if (data <= 0) { 1150 error = EINVAL; 1151 break; 1152 } 1153 num = imin(p->p_numthreads, data); 1154 PROC_UNLOCK(p); 1155 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 1156 tmp = 0; 1157 PROC_LOCK(p); 1158 FOREACH_THREAD_IN_PROC(p, td2) { 1159 if (tmp >= num) 1160 break; 1161 buf[tmp++] = td2->td_tid; 1162 } 1163 PROC_UNLOCK(p); 1164 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 1165 free(buf, M_TEMP); 1166 if (!error) 1167 td->td_retval[0] = tmp; 1168 PROC_LOCK(p); 1169 break; 1170 1171 case PT_VM_TIMESTAMP: 1172 td->td_retval[0] = p->p_vmspace->vm_map.timestamp; 1173 break; 1174 1175 case PT_VM_ENTRY: 1176 PROC_UNLOCK(p); 1177 #ifdef COMPAT_FREEBSD32 1178 if (wrap32) 1179 error = ptrace_vm_entry32(td, p, addr); 1180 else 1181 #endif 1182 error = ptrace_vm_entry(td, p, addr); 1183 PROC_LOCK(p); 1184 break; 1185 1186 default: 1187 #ifdef __HAVE_PTRACE_MACHDEP 1188 if (req >= PT_FIRSTMACH) { 1189 PROC_UNLOCK(p); 1190 error = cpu_ptrace(td2, req, addr, data); 1191 PROC_LOCK(p); 1192 } else 1193 #endif 1194 /* Unknown request. */ 1195 error = EINVAL; 1196 break; 1197 } 1198 1199 out: 1200 /* Drop our hold on this process now that the request has completed. */ 1201 _PRELE(p); 1202 fail: 1203 PROC_UNLOCK(p); 1204 if (proctree_locked) 1205 sx_xunlock(&proctree_lock); 1206 return (error); 1207 } 1208 #undef PROC_READ 1209 #undef PROC_WRITE 1210 1211 /* 1212 * Stop a process because of a debugging event; 1213 * stay stopped until p->p_step is cleared 1214 * (cleared by PIOCCONT in procfs). 1215 */ 1216 void 1217 stopevent(struct proc *p, unsigned int event, unsigned int val) 1218 { 1219 1220 PROC_LOCK_ASSERT(p, MA_OWNED); 1221 p->p_step = 1; 1222 do { 1223 p->p_xstat = val; 1224 p->p_xthread = NULL; 1225 p->p_stype = event; /* Which event caused the stop? */ 1226 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ 1227 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); 1228 } while (p->p_step); 1229 } 1230