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/pioctl.h> 45 #include <sys/priv.h> 46 #include <sys/proc.h> 47 #include <sys/vnode.h> 48 #include <sys/ptrace.h> 49 #include <sys/rwlock.h> 50 #include <sys/sx.h> 51 #include <sys/malloc.h> 52 #include <sys/signalvar.h> 53 54 #include <machine/reg.h> 55 56 #include <security/audit/audit.h> 57 58 #include <vm/vm.h> 59 #include <vm/pmap.h> 60 #include <vm/vm_extern.h> 61 #include <vm/vm_map.h> 62 #include <vm/vm_kern.h> 63 #include <vm/vm_object.h> 64 #include <vm/vm_page.h> 65 #include <vm/vm_param.h> 66 67 #ifdef COMPAT_FREEBSD32 68 #include <sys/procfs.h> 69 #include <compat/freebsd32/freebsd32_signal.h> 70 71 struct ptrace_io_desc32 { 72 int piod_op; 73 uint32_t piod_offs; 74 uint32_t piod_addr; 75 uint32_t piod_len; 76 }; 77 78 struct ptrace_vm_entry32 { 79 int pve_entry; 80 int pve_timestamp; 81 uint32_t pve_start; 82 uint32_t pve_end; 83 uint32_t pve_offset; 84 u_int pve_prot; 85 u_int pve_pathlen; 86 int32_t pve_fileid; 87 u_int pve_fsid; 88 uint32_t pve_path; 89 }; 90 91 struct ptrace_lwpinfo32 { 92 lwpid_t pl_lwpid; /* LWP described. */ 93 int pl_event; /* Event that stopped the LWP. */ 94 int pl_flags; /* LWP flags. */ 95 sigset_t pl_sigmask; /* LWP signal mask */ 96 sigset_t pl_siglist; /* LWP pending signal */ 97 struct siginfo32 pl_siginfo; /* siginfo for signal */ 98 char pl_tdname[MAXCOMLEN + 1]; /* LWP name. */ 99 pid_t pl_child_pid; /* New child pid */ 100 u_int pl_syscall_code; 101 u_int pl_syscall_narg; 102 }; 103 104 #endif 105 106 /* 107 * Functions implemented using PROC_ACTION(): 108 * 109 * proc_read_regs(proc, regs) 110 * Get the current user-visible register set from the process 111 * and copy it into the regs structure (<machine/reg.h>). 112 * The process is stopped at the time read_regs is called. 113 * 114 * proc_write_regs(proc, regs) 115 * Update the current register set from the passed in regs 116 * structure. Take care to avoid clobbering special CPU 117 * registers or privileged bits in the PSL. 118 * Depending on the architecture this may have fix-up work to do, 119 * especially if the IAR or PCW are modified. 120 * The process is stopped at the time write_regs is called. 121 * 122 * proc_read_fpregs, proc_write_fpregs 123 * deal with the floating point register set, otherwise as above. 124 * 125 * proc_read_dbregs, proc_write_dbregs 126 * deal with the processor debug register set, otherwise as above. 127 * 128 * proc_sstep(proc) 129 * Arrange for the process to trap after executing a single instruction. 130 */ 131 132 #define PROC_ACTION(action) do { \ 133 int error; \ 134 \ 135 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ 136 if ((td->td_proc->p_flag & P_INMEM) == 0) \ 137 error = EIO; \ 138 else \ 139 error = (action); \ 140 return (error); \ 141 } while(0) 142 143 int 144 proc_read_regs(struct thread *td, struct reg *regs) 145 { 146 147 PROC_ACTION(fill_regs(td, regs)); 148 } 149 150 int 151 proc_write_regs(struct thread *td, struct reg *regs) 152 { 153 154 PROC_ACTION(set_regs(td, regs)); 155 } 156 157 int 158 proc_read_dbregs(struct thread *td, struct dbreg *dbregs) 159 { 160 161 PROC_ACTION(fill_dbregs(td, dbregs)); 162 } 163 164 int 165 proc_write_dbregs(struct thread *td, struct dbreg *dbregs) 166 { 167 168 PROC_ACTION(set_dbregs(td, dbregs)); 169 } 170 171 /* 172 * Ptrace doesn't support fpregs at all, and there are no security holes 173 * or translations for fpregs, so we can just copy them. 174 */ 175 int 176 proc_read_fpregs(struct thread *td, struct fpreg *fpregs) 177 { 178 179 PROC_ACTION(fill_fpregs(td, fpregs)); 180 } 181 182 int 183 proc_write_fpregs(struct thread *td, struct fpreg *fpregs) 184 { 185 186 PROC_ACTION(set_fpregs(td, fpregs)); 187 } 188 189 #ifdef COMPAT_FREEBSD32 190 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 191 int 192 proc_read_regs32(struct thread *td, struct reg32 *regs32) 193 { 194 195 PROC_ACTION(fill_regs32(td, regs32)); 196 } 197 198 int 199 proc_write_regs32(struct thread *td, struct reg32 *regs32) 200 { 201 202 PROC_ACTION(set_regs32(td, regs32)); 203 } 204 205 int 206 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 207 { 208 209 PROC_ACTION(fill_dbregs32(td, dbregs32)); 210 } 211 212 int 213 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 214 { 215 216 PROC_ACTION(set_dbregs32(td, dbregs32)); 217 } 218 219 int 220 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 221 { 222 223 PROC_ACTION(fill_fpregs32(td, fpregs32)); 224 } 225 226 int 227 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 228 { 229 230 PROC_ACTION(set_fpregs32(td, fpregs32)); 231 } 232 #endif 233 234 int 235 proc_sstep(struct thread *td) 236 { 237 238 PROC_ACTION(ptrace_single_step(td)); 239 } 240 241 int 242 proc_rwmem(struct proc *p, struct uio *uio) 243 { 244 vm_map_t map; 245 vm_offset_t pageno; /* page number */ 246 vm_prot_t reqprot; 247 int error, fault_flags, page_offset, writing; 248 249 /* 250 * Assert that someone has locked this vmspace. (Should be 251 * curthread but we can't assert that.) This keeps the process 252 * from exiting out from under us until this operation completes. 253 */ 254 PROC_ASSERT_HELD(p); 255 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 256 257 /* 258 * The map we want... 259 */ 260 map = &p->p_vmspace->vm_map; 261 262 /* 263 * If we are writing, then we request vm_fault() to create a private 264 * copy of each page. Since these copies will not be writeable by the 265 * process, we must explicity request that they be dirtied. 266 */ 267 writing = uio->uio_rw == UIO_WRITE; 268 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ; 269 fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 270 271 /* 272 * Only map in one page at a time. We don't have to, but it 273 * makes things easier. This way is trivial - right? 274 */ 275 do { 276 vm_offset_t uva; 277 u_int len; 278 vm_page_t m; 279 280 uva = (vm_offset_t)uio->uio_offset; 281 282 /* 283 * Get the page number of this segment. 284 */ 285 pageno = trunc_page(uva); 286 page_offset = uva - pageno; 287 288 /* 289 * How many bytes to copy 290 */ 291 len = min(PAGE_SIZE - page_offset, uio->uio_resid); 292 293 /* 294 * Fault and hold the page on behalf of the process. 295 */ 296 error = vm_fault_hold(map, pageno, reqprot, fault_flags, &m); 297 if (error != KERN_SUCCESS) { 298 if (error == KERN_RESOURCE_SHORTAGE) 299 error = ENOMEM; 300 else 301 error = EFAULT; 302 break; 303 } 304 305 /* 306 * Now do the i/o move. 307 */ 308 error = uiomove_fromphys(&m, page_offset, len, uio); 309 310 /* Make the I-cache coherent for breakpoints. */ 311 if (writing && error == 0) { 312 vm_map_lock_read(map); 313 if (vm_map_check_protection(map, pageno, pageno + 314 PAGE_SIZE, VM_PROT_EXECUTE)) 315 vm_sync_icache(map, uva, len); 316 vm_map_unlock_read(map); 317 } 318 319 /* 320 * Release the page. 321 */ 322 vm_page_lock(m); 323 vm_page_unhold(m); 324 vm_page_unlock(m); 325 326 } while (error == 0 && uio->uio_resid > 0); 327 328 return (error); 329 } 330 331 static ssize_t 332 proc_iop(struct thread *td, struct proc *p, vm_offset_t va, void *buf, 333 size_t len, enum uio_rw rw) 334 { 335 struct iovec iov; 336 struct uio uio; 337 ssize_t slen; 338 int error; 339 340 MPASS(len < SSIZE_MAX); 341 slen = (ssize_t)len; 342 343 iov.iov_base = (caddr_t)buf; 344 iov.iov_len = len; 345 uio.uio_iov = &iov; 346 uio.uio_iovcnt = 1; 347 uio.uio_offset = va; 348 uio.uio_resid = slen; 349 uio.uio_segflg = UIO_SYSSPACE; 350 uio.uio_rw = rw; 351 uio.uio_td = td; 352 error = proc_rwmem(p, &uio); 353 if (uio.uio_resid == slen) 354 return (-1); 355 return (slen - uio.uio_resid); 356 } 357 358 ssize_t 359 proc_readmem(struct thread *td, struct proc *p, vm_offset_t va, void *buf, 360 size_t len) 361 { 362 363 return (proc_iop(td, p, va, buf, len, UIO_READ)); 364 } 365 366 ssize_t 367 proc_writemem(struct thread *td, struct proc *p, vm_offset_t va, void *buf, 368 size_t len) 369 { 370 371 return (proc_iop(td, p, va, buf, len, UIO_WRITE)); 372 } 373 374 static int 375 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve) 376 { 377 struct vattr vattr; 378 vm_map_t map; 379 vm_map_entry_t entry; 380 vm_object_t obj, tobj, lobj; 381 struct vmspace *vm; 382 struct vnode *vp; 383 char *freepath, *fullpath; 384 u_int pathlen; 385 int error, index; 386 387 error = 0; 388 obj = NULL; 389 390 vm = vmspace_acquire_ref(p); 391 map = &vm->vm_map; 392 vm_map_lock_read(map); 393 394 do { 395 entry = map->header.next; 396 index = 0; 397 while (index < pve->pve_entry && entry != &map->header) { 398 entry = entry->next; 399 index++; 400 } 401 if (index != pve->pve_entry) { 402 error = EINVAL; 403 break; 404 } 405 while (entry != &map->header && 406 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) { 407 entry = entry->next; 408 index++; 409 } 410 if (entry == &map->header) { 411 error = ENOENT; 412 break; 413 } 414 415 /* We got an entry. */ 416 pve->pve_entry = index + 1; 417 pve->pve_timestamp = map->timestamp; 418 pve->pve_start = entry->start; 419 pve->pve_end = entry->end - 1; 420 pve->pve_offset = entry->offset; 421 pve->pve_prot = entry->protection; 422 423 /* Backing object's path needed? */ 424 if (pve->pve_pathlen == 0) 425 break; 426 427 pathlen = pve->pve_pathlen; 428 pve->pve_pathlen = 0; 429 430 obj = entry->object.vm_object; 431 if (obj != NULL) 432 VM_OBJECT_RLOCK(obj); 433 } while (0); 434 435 vm_map_unlock_read(map); 436 vmspace_free(vm); 437 438 pve->pve_fsid = VNOVAL; 439 pve->pve_fileid = VNOVAL; 440 441 if (error == 0 && obj != NULL) { 442 lobj = obj; 443 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 444 if (tobj != obj) 445 VM_OBJECT_RLOCK(tobj); 446 if (lobj != obj) 447 VM_OBJECT_RUNLOCK(lobj); 448 lobj = tobj; 449 pve->pve_offset += tobj->backing_object_offset; 450 } 451 vp = vm_object_vnode(lobj); 452 if (vp != NULL) 453 vref(vp); 454 if (lobj != obj) 455 VM_OBJECT_RUNLOCK(lobj); 456 VM_OBJECT_RUNLOCK(obj); 457 458 if (vp != NULL) { 459 freepath = NULL; 460 fullpath = NULL; 461 vn_fullpath(td, vp, &fullpath, &freepath); 462 vn_lock(vp, LK_SHARED | LK_RETRY); 463 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) { 464 pve->pve_fileid = vattr.va_fileid; 465 pve->pve_fsid = vattr.va_fsid; 466 } 467 vput(vp); 468 469 if (fullpath != NULL) { 470 pve->pve_pathlen = strlen(fullpath) + 1; 471 if (pve->pve_pathlen <= pathlen) { 472 error = copyout(fullpath, pve->pve_path, 473 pve->pve_pathlen); 474 } else 475 error = ENAMETOOLONG; 476 } 477 if (freepath != NULL) 478 free(freepath, M_TEMP); 479 } 480 } 481 if (error == 0) 482 CTR3(KTR_PTRACE, "PT_VM_ENTRY: pid %d, entry %d, start %p", 483 p->p_pid, pve->pve_entry, pve->pve_start); 484 485 return (error); 486 } 487 488 #ifdef COMPAT_FREEBSD32 489 static int 490 ptrace_vm_entry32(struct thread *td, struct proc *p, 491 struct ptrace_vm_entry32 *pve32) 492 { 493 struct ptrace_vm_entry pve; 494 int error; 495 496 pve.pve_entry = pve32->pve_entry; 497 pve.pve_pathlen = pve32->pve_pathlen; 498 pve.pve_path = (void *)(uintptr_t)pve32->pve_path; 499 500 error = ptrace_vm_entry(td, p, &pve); 501 if (error == 0) { 502 pve32->pve_entry = pve.pve_entry; 503 pve32->pve_timestamp = pve.pve_timestamp; 504 pve32->pve_start = pve.pve_start; 505 pve32->pve_end = pve.pve_end; 506 pve32->pve_offset = pve.pve_offset; 507 pve32->pve_prot = pve.pve_prot; 508 pve32->pve_fileid = pve.pve_fileid; 509 pve32->pve_fsid = pve.pve_fsid; 510 } 511 512 pve32->pve_pathlen = pve.pve_pathlen; 513 return (error); 514 } 515 516 static void 517 ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl, 518 struct ptrace_lwpinfo32 *pl32) 519 { 520 521 pl32->pl_lwpid = pl->pl_lwpid; 522 pl32->pl_event = pl->pl_event; 523 pl32->pl_flags = pl->pl_flags; 524 pl32->pl_sigmask = pl->pl_sigmask; 525 pl32->pl_siglist = pl->pl_siglist; 526 siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo); 527 strcpy(pl32->pl_tdname, pl->pl_tdname); 528 pl32->pl_child_pid = pl->pl_child_pid; 529 pl32->pl_syscall_code = pl->pl_syscall_code; 530 pl32->pl_syscall_narg = pl->pl_syscall_narg; 531 } 532 #endif /* COMPAT_FREEBSD32 */ 533 534 /* 535 * Process debugging system call. 536 */ 537 #ifndef _SYS_SYSPROTO_H_ 538 struct ptrace_args { 539 int req; 540 pid_t pid; 541 caddr_t addr; 542 int data; 543 }; 544 #endif 545 546 #ifdef COMPAT_FREEBSD32 547 /* 548 * This CPP subterfuge is to try and reduce the number of ifdefs in 549 * the body of the code. 550 * COPYIN(uap->addr, &r.reg, sizeof r.reg); 551 * becomes either: 552 * copyin(uap->addr, &r.reg, sizeof r.reg); 553 * or 554 * copyin(uap->addr, &r.reg32, sizeof r.reg32); 555 * .. except this is done at runtime. 556 */ 557 #define COPYIN(u, k, s) wrap32 ? \ 558 copyin(u, k ## 32, s ## 32) : \ 559 copyin(u, k, s) 560 #define COPYOUT(k, u, s) wrap32 ? \ 561 copyout(k ## 32, u, s ## 32) : \ 562 copyout(k, u, s) 563 #else 564 #define COPYIN(u, k, s) copyin(u, k, s) 565 #define COPYOUT(k, u, s) copyout(k, u, s) 566 #endif 567 int 568 sys_ptrace(struct thread *td, struct ptrace_args *uap) 569 { 570 /* 571 * XXX this obfuscation is to reduce stack usage, but the register 572 * structs may be too large to put on the stack anyway. 573 */ 574 union { 575 struct ptrace_io_desc piod; 576 struct ptrace_lwpinfo pl; 577 struct ptrace_vm_entry pve; 578 struct dbreg dbreg; 579 struct fpreg fpreg; 580 struct reg reg; 581 #ifdef COMPAT_FREEBSD32 582 struct dbreg32 dbreg32; 583 struct fpreg32 fpreg32; 584 struct reg32 reg32; 585 struct ptrace_io_desc32 piod32; 586 struct ptrace_lwpinfo32 pl32; 587 struct ptrace_vm_entry32 pve32; 588 #endif 589 } r; 590 void *addr; 591 int error = 0; 592 #ifdef COMPAT_FREEBSD32 593 int wrap32 = 0; 594 595 if (SV_CURPROC_FLAG(SV_ILP32)) 596 wrap32 = 1; 597 #endif 598 AUDIT_ARG_PID(uap->pid); 599 AUDIT_ARG_CMD(uap->req); 600 AUDIT_ARG_VALUE(uap->data); 601 addr = &r; 602 switch (uap->req) { 603 case PT_GETREGS: 604 case PT_GETFPREGS: 605 case PT_GETDBREGS: 606 case PT_LWPINFO: 607 break; 608 case PT_SETREGS: 609 error = COPYIN(uap->addr, &r.reg, sizeof r.reg); 610 break; 611 case PT_SETFPREGS: 612 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); 613 break; 614 case PT_SETDBREGS: 615 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); 616 break; 617 case PT_IO: 618 error = COPYIN(uap->addr, &r.piod, sizeof r.piod); 619 break; 620 case PT_VM_ENTRY: 621 error = COPYIN(uap->addr, &r.pve, sizeof r.pve); 622 break; 623 default: 624 addr = uap->addr; 625 break; 626 } 627 if (error) 628 return (error); 629 630 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 631 if (error) 632 return (error); 633 634 switch (uap->req) { 635 case PT_VM_ENTRY: 636 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve); 637 break; 638 case PT_IO: 639 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); 640 break; 641 case PT_GETREGS: 642 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); 643 break; 644 case PT_GETFPREGS: 645 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); 646 break; 647 case PT_GETDBREGS: 648 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); 649 break; 650 case PT_LWPINFO: 651 error = copyout(&r.pl, uap->addr, uap->data); 652 break; 653 } 654 655 return (error); 656 } 657 #undef COPYIN 658 #undef COPYOUT 659 660 #ifdef COMPAT_FREEBSD32 661 /* 662 * PROC_READ(regs, td2, addr); 663 * becomes either: 664 * proc_read_regs(td2, addr); 665 * or 666 * proc_read_regs32(td2, addr); 667 * .. except this is done at runtime. There is an additional 668 * complication in that PROC_WRITE disallows 32 bit consumers 669 * from writing to 64 bit address space targets. 670 */ 671 #define PROC_READ(w, t, a) wrap32 ? \ 672 proc_read_ ## w ## 32(t, a) : \ 673 proc_read_ ## w (t, a) 674 #define PROC_WRITE(w, t, a) wrap32 ? \ 675 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 676 proc_write_ ## w (t, a) 677 #else 678 #define PROC_READ(w, t, a) proc_read_ ## w (t, a) 679 #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 680 #endif 681 682 int 683 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 684 { 685 struct iovec iov; 686 struct uio uio; 687 struct proc *curp, *p, *pp; 688 struct thread *td2 = NULL, *td3; 689 struct ptrace_io_desc *piod = NULL; 690 struct ptrace_lwpinfo *pl; 691 int error, num, tmp; 692 int proctree_locked = 0; 693 lwpid_t tid = 0, *buf; 694 #ifdef COMPAT_FREEBSD32 695 int wrap32 = 0, safe = 0; 696 struct ptrace_io_desc32 *piod32 = NULL; 697 struct ptrace_lwpinfo32 *pl32 = NULL; 698 struct ptrace_lwpinfo plr; 699 #endif 700 701 curp = td->td_proc; 702 703 /* Lock proctree before locking the process. */ 704 switch (req) { 705 case PT_TRACE_ME: 706 case PT_ATTACH: 707 case PT_STEP: 708 case PT_CONTINUE: 709 case PT_TO_SCE: 710 case PT_TO_SCX: 711 case PT_SYSCALL: 712 case PT_FOLLOW_FORK: 713 case PT_DETACH: 714 sx_xlock(&proctree_lock); 715 proctree_locked = 1; 716 break; 717 default: 718 break; 719 } 720 721 if (req == PT_TRACE_ME) { 722 p = td->td_proc; 723 PROC_LOCK(p); 724 } else { 725 if (pid <= PID_MAX) { 726 if ((p = pfind(pid)) == NULL) { 727 if (proctree_locked) 728 sx_xunlock(&proctree_lock); 729 return (ESRCH); 730 } 731 } else { 732 td2 = tdfind(pid, -1); 733 if (td2 == NULL) { 734 if (proctree_locked) 735 sx_xunlock(&proctree_lock); 736 return (ESRCH); 737 } 738 p = td2->td_proc; 739 tid = pid; 740 pid = p->p_pid; 741 } 742 } 743 AUDIT_ARG_PROCESS(p); 744 745 if ((p->p_flag & P_WEXIT) != 0) { 746 error = ESRCH; 747 goto fail; 748 } 749 if ((error = p_cansee(td, p)) != 0) 750 goto fail; 751 752 if ((error = p_candebug(td, p)) != 0) 753 goto fail; 754 755 /* 756 * System processes can't be debugged. 757 */ 758 if ((p->p_flag & P_SYSTEM) != 0) { 759 error = EINVAL; 760 goto fail; 761 } 762 763 if (tid == 0) { 764 if ((p->p_flag & P_STOPPED_TRACE) != 0) { 765 KASSERT(p->p_xthread != NULL, ("NULL p_xthread")); 766 td2 = p->p_xthread; 767 } else { 768 td2 = FIRST_THREAD_IN_PROC(p); 769 } 770 tid = td2->td_tid; 771 } 772 773 #ifdef COMPAT_FREEBSD32 774 /* 775 * Test if we're a 32 bit client and what the target is. 776 * Set the wrap controls accordingly. 777 */ 778 if (SV_CURPROC_FLAG(SV_ILP32)) { 779 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32)) 780 safe = 1; 781 wrap32 = 1; 782 } 783 #endif 784 /* 785 * Permissions check 786 */ 787 switch (req) { 788 case PT_TRACE_ME: 789 /* 790 * Always legal, when there is a parent process which 791 * could trace us. Otherwise, reject. 792 */ 793 if ((p->p_flag & P_TRACED) != 0) { 794 error = EBUSY; 795 goto fail; 796 } 797 if (p->p_pptr == initproc) { 798 error = EPERM; 799 goto fail; 800 } 801 break; 802 803 case PT_ATTACH: 804 /* Self */ 805 if (p == td->td_proc) { 806 error = EINVAL; 807 goto fail; 808 } 809 810 /* Already traced */ 811 if (p->p_flag & P_TRACED) { 812 error = EBUSY; 813 goto fail; 814 } 815 816 /* Can't trace an ancestor if you're being traced. */ 817 if (curp->p_flag & P_TRACED) { 818 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 819 if (pp == p) { 820 error = EINVAL; 821 goto fail; 822 } 823 } 824 } 825 826 827 /* OK */ 828 break; 829 830 case PT_CLEARSTEP: 831 /* Allow thread to clear single step for itself */ 832 if (td->td_tid == tid) 833 break; 834 835 /* FALLTHROUGH */ 836 default: 837 /* not being traced... */ 838 if ((p->p_flag & P_TRACED) == 0) { 839 error = EPERM; 840 goto fail; 841 } 842 843 /* not being traced by YOU */ 844 if (p->p_pptr != td->td_proc) { 845 error = EBUSY; 846 goto fail; 847 } 848 849 /* not currently stopped */ 850 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 || 851 p->p_suspcount != p->p_numthreads || 852 (p->p_flag & P_WAITED) == 0) { 853 error = EBUSY; 854 goto fail; 855 } 856 857 if ((p->p_flag & P_STOPPED_TRACE) == 0) { 858 static int count = 0; 859 if (count++ == 0) 860 printf("P_STOPPED_TRACE not set.\n"); 861 } 862 863 /* OK */ 864 break; 865 } 866 867 /* Keep this process around until we finish this request. */ 868 _PHOLD(p); 869 870 #ifdef FIX_SSTEP 871 /* 872 * Single step fixup ala procfs 873 */ 874 FIX_SSTEP(td2); 875 #endif 876 877 /* 878 * Actually do the requests 879 */ 880 881 td->td_retval[0] = 0; 882 883 switch (req) { 884 case PT_TRACE_ME: 885 /* set my trace flag and "owner" so it can read/write me */ 886 p->p_flag |= P_TRACED; 887 if (p->p_flag & P_PPWAIT) 888 p->p_flag |= P_PPTRACE; 889 p->p_oppid = p->p_pptr->p_pid; 890 CTR1(KTR_PTRACE, "PT_TRACE_ME: pid %d", p->p_pid); 891 break; 892 893 case PT_ATTACH: 894 /* security check done above */ 895 /* 896 * It would be nice if the tracing relationship was separate 897 * from the parent relationship but that would require 898 * another set of links in the proc struct or for "wait" 899 * to scan the entire proc table. To make life easier, 900 * we just re-parent the process we're trying to trace. 901 * The old parent is remembered so we can put things back 902 * on a "detach". 903 */ 904 p->p_flag |= P_TRACED; 905 p->p_oppid = p->p_pptr->p_pid; 906 if (p->p_pptr != td->td_proc) { 907 proc_reparent(p, td->td_proc); 908 } 909 data = SIGSTOP; 910 CTR2(KTR_PTRACE, "PT_ATTACH: pid %d, oppid %d", p->p_pid, 911 p->p_oppid); 912 goto sendsig; /* in PT_CONTINUE below */ 913 914 case PT_CLEARSTEP: 915 CTR2(KTR_PTRACE, "PT_CLEARSTEP: tid %d (pid %d)", td2->td_tid, 916 p->p_pid); 917 error = ptrace_clear_single_step(td2); 918 break; 919 920 case PT_SETSTEP: 921 CTR2(KTR_PTRACE, "PT_SETSTEP: tid %d (pid %d)", td2->td_tid, 922 p->p_pid); 923 error = ptrace_single_step(td2); 924 break; 925 926 case PT_SUSPEND: 927 CTR2(KTR_PTRACE, "PT_SUSPEND: tid %d (pid %d)", td2->td_tid, 928 p->p_pid); 929 td2->td_dbgflags |= TDB_SUSPEND; 930 thread_lock(td2); 931 td2->td_flags |= TDF_NEEDSUSPCHK; 932 thread_unlock(td2); 933 break; 934 935 case PT_RESUME: 936 CTR2(KTR_PTRACE, "PT_RESUME: tid %d (pid %d)", td2->td_tid, 937 p->p_pid); 938 td2->td_dbgflags &= ~TDB_SUSPEND; 939 break; 940 941 case PT_FOLLOW_FORK: 942 CTR3(KTR_PTRACE, "PT_FOLLOW_FORK: pid %d %s -> %s", p->p_pid, 943 p->p_flag & P_FOLLOWFORK ? "enabled" : "disabled", 944 data ? "enabled" : "disabled"); 945 if (data) 946 p->p_flag |= P_FOLLOWFORK; 947 else 948 p->p_flag &= ~P_FOLLOWFORK; 949 break; 950 951 case PT_STEP: 952 case PT_CONTINUE: 953 case PT_TO_SCE: 954 case PT_TO_SCX: 955 case PT_SYSCALL: 956 case PT_DETACH: 957 /* Zero means do not send any signal */ 958 if (data < 0 || data > _SIG_MAXSIG) { 959 error = EINVAL; 960 break; 961 } 962 963 switch (req) { 964 case PT_STEP: 965 CTR2(KTR_PTRACE, "PT_STEP: tid %d (pid %d)", 966 td2->td_tid, p->p_pid); 967 error = ptrace_single_step(td2); 968 if (error) 969 goto out; 970 break; 971 case PT_CONTINUE: 972 case PT_TO_SCE: 973 case PT_TO_SCX: 974 case PT_SYSCALL: 975 if (addr != (void *)1) { 976 error = ptrace_set_pc(td2, 977 (u_long)(uintfptr_t)addr); 978 if (error) 979 goto out; 980 } 981 switch (req) { 982 case PT_TO_SCE: 983 p->p_stops |= S_PT_SCE; 984 CTR4(KTR_PTRACE, 985 "PT_TO_SCE: pid %d, stops = %#x, PC = %#lx, sig = %d", 986 p->p_pid, p->p_stops, 987 (u_long)(uintfptr_t)addr, data); 988 break; 989 case PT_TO_SCX: 990 p->p_stops |= S_PT_SCX; 991 CTR4(KTR_PTRACE, 992 "PT_TO_SCX: pid %d, stops = %#x, PC = %#lx, sig = %d", 993 p->p_pid, p->p_stops, 994 (u_long)(uintfptr_t)addr, data); 995 break; 996 case PT_SYSCALL: 997 p->p_stops |= S_PT_SCE | S_PT_SCX; 998 CTR4(KTR_PTRACE, 999 "PT_SYSCALL: pid %d, stops = %#x, PC = %#lx, sig = %d", 1000 p->p_pid, p->p_stops, 1001 (u_long)(uintfptr_t)addr, data); 1002 break; 1003 case PT_CONTINUE: 1004 CTR3(KTR_PTRACE, 1005 "PT_CONTINUE: pid %d, PC = %#lx, sig = %d", 1006 p->p_pid, (u_long)(uintfptr_t)addr, data); 1007 break; 1008 } 1009 break; 1010 case PT_DETACH: 1011 /* 1012 * Reset the process parent. 1013 * 1014 * NB: This clears P_TRACED before reparenting 1015 * a detached process back to its original 1016 * parent. Otherwise the debugee will be set 1017 * as an orphan of the debugger. 1018 */ 1019 p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK); 1020 if (p->p_oppid != p->p_pptr->p_pid) { 1021 PROC_LOCK(p->p_pptr); 1022 sigqueue_take(p->p_ksi); 1023 PROC_UNLOCK(p->p_pptr); 1024 1025 pp = proc_realparent(p); 1026 proc_reparent(p, pp); 1027 if (pp == initproc) 1028 p->p_sigparent = SIGCHLD; 1029 CTR3(KTR_PTRACE, 1030 "PT_DETACH: pid %d reparented to pid %d, sig %d", 1031 p->p_pid, pp->p_pid, data); 1032 } else 1033 CTR2(KTR_PTRACE, "PT_DETACH: pid %d, sig %d", 1034 p->p_pid, data); 1035 p->p_oppid = 0; 1036 p->p_stops = 0; 1037 1038 /* should we send SIGCHLD? */ 1039 /* childproc_continued(p); */ 1040 break; 1041 } 1042 1043 sendsig: 1044 if (proctree_locked) { 1045 sx_xunlock(&proctree_lock); 1046 proctree_locked = 0; 1047 } 1048 p->p_xsig = data; 1049 p->p_xthread = NULL; 1050 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) { 1051 /* deliver or queue signal */ 1052 td2->td_dbgflags &= ~TDB_XSIG; 1053 td2->td_xsig = data; 1054 1055 if (req == PT_DETACH) { 1056 FOREACH_THREAD_IN_PROC(p, td3) 1057 td3->td_dbgflags &= ~TDB_SUSPEND; 1058 } 1059 /* 1060 * unsuspend all threads, to not let a thread run, 1061 * you should use PT_SUSPEND to suspend it before 1062 * continuing process. 1063 */ 1064 PROC_SLOCK(p); 1065 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED); 1066 thread_unsuspend(p); 1067 PROC_SUNLOCK(p); 1068 if (req == PT_ATTACH) 1069 kern_psignal(p, data); 1070 } else { 1071 if (data) 1072 kern_psignal(p, data); 1073 } 1074 break; 1075 1076 case PT_WRITE_I: 1077 case PT_WRITE_D: 1078 td2->td_dbgflags |= TDB_USERWR; 1079 PROC_UNLOCK(p); 1080 error = 0; 1081 if (proc_writemem(td, p, (off_t)(uintptr_t)addr, &data, 1082 sizeof(int)) != sizeof(int)) 1083 error = ENOMEM; 1084 else 1085 CTR3(KTR_PTRACE, "PT_WRITE: pid %d: %p <= %#x", 1086 p->p_pid, addr, data); 1087 PROC_LOCK(p); 1088 break; 1089 1090 case PT_READ_I: 1091 case PT_READ_D: 1092 PROC_UNLOCK(p); 1093 error = tmp = 0; 1094 if (proc_readmem(td, p, (off_t)(uintptr_t)addr, &tmp, 1095 sizeof(int)) != sizeof(int)) 1096 error = ENOMEM; 1097 else 1098 CTR3(KTR_PTRACE, "PT_READ: pid %d: %p >= %#x", 1099 p->p_pid, addr, tmp); 1100 td->td_retval[0] = tmp; 1101 PROC_LOCK(p); 1102 break; 1103 1104 case PT_IO: 1105 #ifdef COMPAT_FREEBSD32 1106 if (wrap32) { 1107 piod32 = addr; 1108 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; 1109 iov.iov_len = piod32->piod_len; 1110 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; 1111 uio.uio_resid = piod32->piod_len; 1112 } else 1113 #endif 1114 { 1115 piod = addr; 1116 iov.iov_base = piod->piod_addr; 1117 iov.iov_len = piod->piod_len; 1118 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 1119 uio.uio_resid = piod->piod_len; 1120 } 1121 uio.uio_iov = &iov; 1122 uio.uio_iovcnt = 1; 1123 uio.uio_segflg = UIO_USERSPACE; 1124 uio.uio_td = td; 1125 #ifdef COMPAT_FREEBSD32 1126 tmp = wrap32 ? piod32->piod_op : piod->piod_op; 1127 #else 1128 tmp = piod->piod_op; 1129 #endif 1130 switch (tmp) { 1131 case PIOD_READ_D: 1132 case PIOD_READ_I: 1133 CTR3(KTR_PTRACE, "PT_IO: pid %d: READ (%p, %#x)", 1134 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid); 1135 uio.uio_rw = UIO_READ; 1136 break; 1137 case PIOD_WRITE_D: 1138 case PIOD_WRITE_I: 1139 CTR3(KTR_PTRACE, "PT_IO: pid %d: WRITE (%p, %#x)", 1140 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid); 1141 td2->td_dbgflags |= TDB_USERWR; 1142 uio.uio_rw = UIO_WRITE; 1143 break; 1144 default: 1145 error = EINVAL; 1146 goto out; 1147 } 1148 PROC_UNLOCK(p); 1149 error = proc_rwmem(p, &uio); 1150 #ifdef COMPAT_FREEBSD32 1151 if (wrap32) 1152 piod32->piod_len -= uio.uio_resid; 1153 else 1154 #endif 1155 piod->piod_len -= uio.uio_resid; 1156 PROC_LOCK(p); 1157 break; 1158 1159 case PT_KILL: 1160 CTR1(KTR_PTRACE, "PT_KILL: pid %d", p->p_pid); 1161 data = SIGKILL; 1162 goto sendsig; /* in PT_CONTINUE above */ 1163 1164 case PT_SETREGS: 1165 CTR2(KTR_PTRACE, "PT_SETREGS: tid %d (pid %d)", td2->td_tid, 1166 p->p_pid); 1167 td2->td_dbgflags |= TDB_USERWR; 1168 error = PROC_WRITE(regs, td2, addr); 1169 break; 1170 1171 case PT_GETREGS: 1172 CTR2(KTR_PTRACE, "PT_GETREGS: tid %d (pid %d)", td2->td_tid, 1173 p->p_pid); 1174 error = PROC_READ(regs, td2, addr); 1175 break; 1176 1177 case PT_SETFPREGS: 1178 CTR2(KTR_PTRACE, "PT_SETFPREGS: tid %d (pid %d)", td2->td_tid, 1179 p->p_pid); 1180 td2->td_dbgflags |= TDB_USERWR; 1181 error = PROC_WRITE(fpregs, td2, addr); 1182 break; 1183 1184 case PT_GETFPREGS: 1185 CTR2(KTR_PTRACE, "PT_GETFPREGS: tid %d (pid %d)", td2->td_tid, 1186 p->p_pid); 1187 error = PROC_READ(fpregs, td2, addr); 1188 break; 1189 1190 case PT_SETDBREGS: 1191 CTR2(KTR_PTRACE, "PT_SETDBREGS: tid %d (pid %d)", td2->td_tid, 1192 p->p_pid); 1193 td2->td_dbgflags |= TDB_USERWR; 1194 error = PROC_WRITE(dbregs, td2, addr); 1195 break; 1196 1197 case PT_GETDBREGS: 1198 CTR2(KTR_PTRACE, "PT_GETDBREGS: tid %d (pid %d)", td2->td_tid, 1199 p->p_pid); 1200 error = PROC_READ(dbregs, td2, addr); 1201 break; 1202 1203 case PT_LWPINFO: 1204 if (data <= 0 || 1205 #ifdef COMPAT_FREEBSD32 1206 (!wrap32 && data > sizeof(*pl)) || 1207 (wrap32 && data > sizeof(*pl32))) { 1208 #else 1209 data > sizeof(*pl)) { 1210 #endif 1211 error = EINVAL; 1212 break; 1213 } 1214 #ifdef COMPAT_FREEBSD32 1215 if (wrap32) { 1216 pl = &plr; 1217 pl32 = addr; 1218 } else 1219 #endif 1220 pl = addr; 1221 pl->pl_lwpid = td2->td_tid; 1222 pl->pl_event = PL_EVENT_NONE; 1223 pl->pl_flags = 0; 1224 if (td2->td_dbgflags & TDB_XSIG) { 1225 pl->pl_event = PL_EVENT_SIGNAL; 1226 if (td2->td_dbgksi.ksi_signo != 0 && 1227 #ifdef COMPAT_FREEBSD32 1228 ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo, 1229 pl_siginfo) + sizeof(pl->pl_siginfo)) || 1230 (wrap32 && data >= offsetof(struct ptrace_lwpinfo32, 1231 pl_siginfo) + sizeof(struct siginfo32))) 1232 #else 1233 data >= offsetof(struct ptrace_lwpinfo, pl_siginfo) 1234 + sizeof(pl->pl_siginfo) 1235 #endif 1236 ){ 1237 pl->pl_flags |= PL_FLAG_SI; 1238 pl->pl_siginfo = td2->td_dbgksi.ksi_info; 1239 } 1240 } 1241 if ((pl->pl_flags & PL_FLAG_SI) == 0) 1242 bzero(&pl->pl_siginfo, sizeof(pl->pl_siginfo)); 1243 if (td2->td_dbgflags & TDB_SCE) 1244 pl->pl_flags |= PL_FLAG_SCE; 1245 else if (td2->td_dbgflags & TDB_SCX) 1246 pl->pl_flags |= PL_FLAG_SCX; 1247 if (td2->td_dbgflags & TDB_EXEC) 1248 pl->pl_flags |= PL_FLAG_EXEC; 1249 if (td2->td_dbgflags & TDB_FORK) { 1250 pl->pl_flags |= PL_FLAG_FORKED; 1251 pl->pl_child_pid = td2->td_dbg_forked; 1252 } 1253 if (td2->td_dbgflags & TDB_CHILD) 1254 pl->pl_flags |= PL_FLAG_CHILD; 1255 pl->pl_sigmask = td2->td_sigmask; 1256 pl->pl_siglist = td2->td_siglist; 1257 strcpy(pl->pl_tdname, td2->td_name); 1258 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) != 0) { 1259 pl->pl_syscall_code = td2->td_dbg_sc_code; 1260 pl->pl_syscall_narg = td2->td_dbg_sc_narg; 1261 } else { 1262 pl->pl_syscall_code = 0; 1263 pl->pl_syscall_narg = 0; 1264 } 1265 #ifdef COMPAT_FREEBSD32 1266 if (wrap32) 1267 ptrace_lwpinfo_to32(pl, pl32); 1268 #endif 1269 CTR6(KTR_PTRACE, 1270 "PT_LWPINFO: tid %d (pid %d) event %d flags %#x child pid %d syscall %d", 1271 td2->td_tid, p->p_pid, pl->pl_event, pl->pl_flags, 1272 pl->pl_child_pid, pl->pl_syscall_code); 1273 break; 1274 1275 case PT_GETNUMLWPS: 1276 CTR2(KTR_PTRACE, "PT_GETNUMLWPS: pid %d: %d threads", p->p_pid, 1277 p->p_numthreads); 1278 td->td_retval[0] = p->p_numthreads; 1279 break; 1280 1281 case PT_GETLWPLIST: 1282 CTR3(KTR_PTRACE, "PT_GETLWPLIST: pid %d: data %d, actual %d", 1283 p->p_pid, data, p->p_numthreads); 1284 if (data <= 0) { 1285 error = EINVAL; 1286 break; 1287 } 1288 num = imin(p->p_numthreads, data); 1289 PROC_UNLOCK(p); 1290 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 1291 tmp = 0; 1292 PROC_LOCK(p); 1293 FOREACH_THREAD_IN_PROC(p, td2) { 1294 if (tmp >= num) 1295 break; 1296 buf[tmp++] = td2->td_tid; 1297 } 1298 PROC_UNLOCK(p); 1299 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 1300 free(buf, M_TEMP); 1301 if (!error) 1302 td->td_retval[0] = tmp; 1303 PROC_LOCK(p); 1304 break; 1305 1306 case PT_VM_TIMESTAMP: 1307 CTR2(KTR_PTRACE, "PT_VM_TIMESTAMP: pid %d: timestamp %d", 1308 p->p_pid, p->p_vmspace->vm_map.timestamp); 1309 td->td_retval[0] = p->p_vmspace->vm_map.timestamp; 1310 break; 1311 1312 case PT_VM_ENTRY: 1313 PROC_UNLOCK(p); 1314 #ifdef COMPAT_FREEBSD32 1315 if (wrap32) 1316 error = ptrace_vm_entry32(td, p, addr); 1317 else 1318 #endif 1319 error = ptrace_vm_entry(td, p, addr); 1320 PROC_LOCK(p); 1321 break; 1322 1323 default: 1324 #ifdef __HAVE_PTRACE_MACHDEP 1325 if (req >= PT_FIRSTMACH) { 1326 PROC_UNLOCK(p); 1327 error = cpu_ptrace(td2, req, addr, data); 1328 PROC_LOCK(p); 1329 } else 1330 #endif 1331 /* Unknown request. */ 1332 error = EINVAL; 1333 break; 1334 } 1335 1336 out: 1337 /* Drop our hold on this process now that the request has completed. */ 1338 _PRELE(p); 1339 fail: 1340 PROC_UNLOCK(p); 1341 if (proctree_locked) 1342 sx_xunlock(&proctree_lock); 1343 return (error); 1344 } 1345 #undef PROC_READ 1346 #undef PROC_WRITE 1347 1348 /* 1349 * Stop a process because of a debugging event; 1350 * stay stopped until p->p_step is cleared 1351 * (cleared by PIOCCONT in procfs). 1352 */ 1353 void 1354 stopevent(struct proc *p, unsigned int event, unsigned int val) 1355 { 1356 1357 PROC_LOCK_ASSERT(p, MA_OWNED); 1358 p->p_step = 1; 1359 CTR3(KTR_PTRACE, "stopevent: pid %d event %u val %u", p->p_pid, event, 1360 val); 1361 do { 1362 if (event != S_EXIT) 1363 p->p_xsig = val; 1364 p->p_xthread = NULL; 1365 p->p_stype = event; /* Which event caused the stop? */ 1366 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ 1367 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); 1368 } while (p->p_step); 1369 } 1370