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/priv.h> 45#include <sys/proc.h> 46#include <sys/procctl.h> 47#include <sys/vnode.h> 48#include <sys/ptrace.h> 49#include <sys/sx.h> 50#include <sys/malloc.h> 51#include <sys/signalvar.h> 52 53#include <machine/reg.h> 54 55#include <security/audit/audit.h> 56 57#include <vm/vm.h> 58#include <vm/pmap.h> 59#include <vm/vm_extern.h> 60#include <vm/vm_map.h> 61#include <vm/vm_kern.h> 62#include <vm/vm_object.h> 63#include <vm/vm_page.h> 64#include <vm/vm_pager.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 71struct ptrace_io_desc32 { 72 int piod_op; 73 uint32_t piod_offs; 74 uint32_t piod_addr; 75 uint32_t piod_len; 76}; 77 78struct 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 91struct 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 int pl_child_pid; /* New child pid */ 100}; 101 102#endif 103 104/* 105 * Functions implemented using PROC_ACTION(): 106 * 107 * proc_read_regs(proc, regs) 108 * Get the current user-visible register set from the process 109 * and copy it into the regs structure (<machine/reg.h>). 110 * The process is stopped at the time read_regs is called. 111 * 112 * proc_write_regs(proc, regs) 113 * Update the current register set from the passed in regs 114 * structure. Take care to avoid clobbering special CPU 115 * registers or privileged bits in the PSL. 116 * Depending on the architecture this may have fix-up work to do, 117 * especially if the IAR or PCW are modified. 118 * The process is stopped at the time write_regs is called. 119 * 120 * proc_read_fpregs, proc_write_fpregs 121 * deal with the floating point register set, otherwise as above. 122 * 123 * proc_read_dbregs, proc_write_dbregs 124 * deal with the processor debug register set, otherwise as above. 125 * 126 * proc_sstep(proc) 127 * Arrange for the process to trap after executing a single instruction. 128 */ 129 130#define PROC_ACTION(action) do { \ 131 int error; \ 132 \ 133 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ 134 if ((td->td_proc->p_flag & P_INMEM) == 0) \ 135 error = EIO; \ 136 else \ 137 error = (action); \ 138 return (error); \ 139} while(0) 140 141int 142proc_read_regs(struct thread *td, struct reg *regs) 143{ 144 145 PROC_ACTION(fill_regs(td, regs)); 146} 147 148int 149proc_write_regs(struct thread *td, struct reg *regs) 150{ 151 152 PROC_ACTION(set_regs(td, regs)); 153} 154 155int 156proc_read_dbregs(struct thread *td, struct dbreg *dbregs) 157{ 158 159 PROC_ACTION(fill_dbregs(td, dbregs)); 160} 161 162int 163proc_write_dbregs(struct thread *td, struct dbreg *dbregs) 164{ 165 166 PROC_ACTION(set_dbregs(td, dbregs)); 167} 168 169/* 170 * Ptrace doesn't support fpregs at all, and there are no security holes 171 * or translations for fpregs, so we can just copy them. 172 */ 173int 174proc_read_fpregs(struct thread *td, struct fpreg *fpregs) 175{ 176 177 PROC_ACTION(fill_fpregs(td, fpregs)); 178} 179 180int 181proc_write_fpregs(struct thread *td, struct fpreg *fpregs) 182{ 183 184 PROC_ACTION(set_fpregs(td, fpregs)); 185} 186 187#ifdef COMPAT_FREEBSD32 188/* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 189int 190proc_read_regs32(struct thread *td, struct reg32 *regs32) 191{ 192 193 PROC_ACTION(fill_regs32(td, regs32)); 194} 195 196int 197proc_write_regs32(struct thread *td, struct reg32 *regs32) 198{ 199 200 PROC_ACTION(set_regs32(td, regs32)); 201} 202 203int 204proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 205{ 206 207 PROC_ACTION(fill_dbregs32(td, dbregs32)); 208} 209 210int 211proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 212{ 213 214 PROC_ACTION(set_dbregs32(td, dbregs32)); 215} 216 217int 218proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 219{ 220 221 PROC_ACTION(fill_fpregs32(td, fpregs32)); 222} 223 224int 225proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 226{ 227 228 PROC_ACTION(set_fpregs32(td, fpregs32)); 229} 230#endif 231 232int 233proc_sstep(struct thread *td) 234{ 235 236 PROC_ACTION(ptrace_single_step(td)); 237} 238 239int 240proc_rwmem(struct proc *p, struct uio *uio) 241{ 242 vm_map_t map; 243 vm_offset_t pageno; /* page number */ 244 vm_prot_t reqprot; 245 int error, fault_flags, page_offset, writing; 246 247 /* 248 * Assert that someone has locked this vmspace. (Should be 249 * curthread but we can't assert that.) This keeps the process 250 * from exiting out from under us until this operation completes. 251 */ 252 KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__, 253 p, p->p_pid)); 254 255 /* 256 * The map we want... 257 */ 258 map = &p->p_vmspace->vm_map; 259 260 /* 261 * If we are writing, then we request vm_fault() to create a private 262 * copy of each page. Since these copies will not be writeable by the 263 * process, we must explicity request that they be dirtied. 264 */ 265 writing = uio->uio_rw == UIO_WRITE; 266 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ; 267 fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 268 269 /* 270 * Only map in one page at a time. We don't have to, but it 271 * makes things easier. This way is trivial - right? 272 */ 273 do { 274 vm_offset_t uva; 275 u_int len; 276 vm_page_t m; 277 278 uva = (vm_offset_t)uio->uio_offset; 279 280 /* 281 * Get the page number of this segment. 282 */ 283 pageno = trunc_page(uva); 284 page_offset = uva - pageno; 285 286 /* 287 * How many bytes to copy 288 */ 289 len = min(PAGE_SIZE - page_offset, uio->uio_resid); 290 291 /* 292 * Fault and hold the page on behalf of the process. 293 */ 294 error = vm_fault_hold(map, pageno, reqprot, fault_flags, &m); 295 if (error != KERN_SUCCESS) { 296 if (error == KERN_RESOURCE_SHORTAGE) 297 error = ENOMEM; 298 else 299 error = EFAULT; 300 break; 301 } 302 303 /* 304 * Now do the i/o move. 305 */ 306 error = uiomove_fromphys(&m, page_offset, len, uio); 307 308 /* Make the I-cache coherent for breakpoints. */ 309 if (writing && error == 0) { 310 vm_map_lock_read(map); 311 if (vm_map_check_protection(map, pageno, pageno + 312 PAGE_SIZE, VM_PROT_EXECUTE)) 313 vm_sync_icache(map, uva, len); 314 vm_map_unlock_read(map); 315 } 316 317 /* 318 * Release the page. 319 */ 320 vm_page_lock(m); 321 vm_page_unhold(m); 322 vm_page_unlock(m); 323 324 } while (error == 0 && uio->uio_resid > 0); 325 326 return (error); 327} 328 329static int 330ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve) 331{ 332 struct vattr vattr; 333 vm_map_t map; 334 vm_map_entry_t entry; 335 vm_object_t obj, tobj, lobj; 336 struct vmspace *vm; 337 struct vnode *vp; 338 char *freepath, *fullpath; 339 u_int pathlen; 340 int error, index, vfslocked; 341 342 error = 0; 343 obj = NULL; 344 345 vm = vmspace_acquire_ref(p); 346 map = &vm->vm_map; 347 vm_map_lock_read(map); 348 349 do { 350 entry = map->header.next; 351 index = 0; 352 while (index < pve->pve_entry && entry != &map->header) { 353 entry = entry->next; 354 index++; 355 } 356 if (index != pve->pve_entry) { 357 error = EINVAL; 358 break; 359 } 360 while (entry != &map->header && 361 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) { 362 entry = entry->next; 363 index++; 364 } 365 if (entry == &map->header) { 366 error = ENOENT; 367 break; 368 } 369 370 /* We got an entry. */ 371 pve->pve_entry = index + 1; 372 pve->pve_timestamp = map->timestamp; 373 pve->pve_start = entry->start; 374 pve->pve_end = entry->end - 1; 375 pve->pve_offset = entry->offset; 376 pve->pve_prot = entry->protection; 377 378 /* Backing object's path needed? */ 379 if (pve->pve_pathlen == 0) 380 break; 381 382 pathlen = pve->pve_pathlen; 383 pve->pve_pathlen = 0; 384 385 obj = entry->object.vm_object; 386 if (obj != NULL) 387 VM_OBJECT_LOCK(obj); 388 } while (0); 389 390 vm_map_unlock_read(map); 391 vmspace_free(vm); 392 393 pve->pve_fsid = VNOVAL; 394 pve->pve_fileid = VNOVAL; 395 396 if (error == 0 && obj != NULL) { 397 lobj = obj; 398 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 399 if (tobj != obj) 400 VM_OBJECT_LOCK(tobj); 401 if (lobj != obj) 402 VM_OBJECT_UNLOCK(lobj); 403 lobj = tobj; 404 pve->pve_offset += tobj->backing_object_offset; 405 } 406 vp = (lobj->type == OBJT_VNODE) ? lobj->handle : NULL; 407 if (vp != NULL) 408 vref(vp); 409 if (lobj != obj) 410 VM_OBJECT_UNLOCK(lobj); 411 VM_OBJECT_UNLOCK(obj); 412 413 if (vp != NULL) { 414 freepath = NULL; 415 fullpath = NULL; 416 vn_fullpath(td, vp, &fullpath, &freepath); 417 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 418 vn_lock(vp, LK_SHARED | LK_RETRY); 419 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) { 420 pve->pve_fileid = vattr.va_fileid; 421 pve->pve_fsid = vattr.va_fsid; 422 } 423 vput(vp); 424 VFS_UNLOCK_GIANT(vfslocked); 425 426 if (fullpath != NULL) { 427 pve->pve_pathlen = strlen(fullpath) + 1; 428 if (pve->pve_pathlen <= pathlen) { 429 error = copyout(fullpath, pve->pve_path, 430 pve->pve_pathlen); 431 } else 432 error = ENAMETOOLONG; 433 } 434 if (freepath != NULL) 435 free(freepath, M_TEMP); 436 } 437 } 438 439 return (error); 440} 441 442#ifdef COMPAT_FREEBSD32 443static int 444ptrace_vm_entry32(struct thread *td, struct proc *p, 445 struct ptrace_vm_entry32 *pve32) 446{ 447 struct ptrace_vm_entry pve; 448 int error; 449 450 pve.pve_entry = pve32->pve_entry; 451 pve.pve_pathlen = pve32->pve_pathlen; 452 pve.pve_path = (void *)(uintptr_t)pve32->pve_path; 453 454 error = ptrace_vm_entry(td, p, &pve); 455 if (error == 0) { 456 pve32->pve_entry = pve.pve_entry; 457 pve32->pve_timestamp = pve.pve_timestamp; 458 pve32->pve_start = pve.pve_start; 459 pve32->pve_end = pve.pve_end; 460 pve32->pve_offset = pve.pve_offset; 461 pve32->pve_prot = pve.pve_prot; 462 pve32->pve_fileid = pve.pve_fileid; 463 pve32->pve_fsid = pve.pve_fsid; 464 } 465 466 pve32->pve_pathlen = pve.pve_pathlen; 467 return (error); 468} 469 470static void 471ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl, 472 struct ptrace_lwpinfo32 *pl32) 473{ 474 475 pl32->pl_lwpid = pl->pl_lwpid; 476 pl32->pl_event = pl->pl_event; 477 pl32->pl_flags = pl->pl_flags; 478 pl32->pl_sigmask = pl->pl_sigmask; 479 pl32->pl_siglist = pl->pl_siglist; 480 siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo); 481 strcpy(pl32->pl_tdname, pl->pl_tdname); 482 pl32->pl_child_pid = pl->pl_child_pid; 483} 484#endif /* COMPAT_FREEBSD32 */ 485 486/* 487 * Process debugging system call. 488 */ 489#ifndef _SYS_SYSPROTO_H_ 490struct ptrace_args { 491 int req; 492 pid_t pid; 493 caddr_t addr; 494 int data; 495}; 496#endif 497 498#ifdef COMPAT_FREEBSD32 499/* 500 * This CPP subterfuge is to try and reduce the number of ifdefs in 501 * the body of the code. 502 * COPYIN(uap->addr, &r.reg, sizeof r.reg); 503 * becomes either: 504 * copyin(uap->addr, &r.reg, sizeof r.reg); 505 * or 506 * copyin(uap->addr, &r.reg32, sizeof r.reg32); 507 * .. except this is done at runtime. 508 */ 509#define COPYIN(u, k, s) wrap32 ? \ 510 copyin(u, k ## 32, s ## 32) : \ 511 copyin(u, k, s) 512#define COPYOUT(k, u, s) wrap32 ? \ 513 copyout(k ## 32, u, s ## 32) : \ 514 copyout(k, u, s) 515#else 516#define COPYIN(u, k, s) copyin(u, k, s) 517#define COPYOUT(k, u, s) copyout(k, u, s) 518#endif 519int 520sys_ptrace(struct thread *td, struct ptrace_args *uap) 521{ 522 /* 523 * XXX this obfuscation is to reduce stack usage, but the register 524 * structs may be too large to put on the stack anyway. 525 */ 526 union { 527 struct ptrace_io_desc piod; 528 struct ptrace_lwpinfo pl; 529 struct ptrace_vm_entry pve; 530 struct dbreg dbreg; 531 struct fpreg fpreg; 532 struct reg reg; 533#ifdef COMPAT_FREEBSD32 534 struct dbreg32 dbreg32; 535 struct fpreg32 fpreg32; 536 struct reg32 reg32; 537 struct ptrace_io_desc32 piod32; 538 struct ptrace_lwpinfo32 pl32; 539 struct ptrace_vm_entry32 pve32; 540#endif 541 } r; 542 void *addr; 543 int error = 0; 544#ifdef COMPAT_FREEBSD32 545 int wrap32 = 0; 546 547 if (SV_CURPROC_FLAG(SV_ILP32)) 548 wrap32 = 1; 549#endif 550 AUDIT_ARG_PID(uap->pid); 551 AUDIT_ARG_CMD(uap->req); 552 AUDIT_ARG_VALUE(uap->data); 553 addr = &r; 554 switch (uap->req) { 555 case PT_GETREGS: 556 case PT_GETFPREGS: 557 case PT_GETDBREGS: 558 case PT_LWPINFO: 559 break; 560 case PT_SETREGS: 561 error = COPYIN(uap->addr, &r.reg, sizeof r.reg); 562 break; 563 case PT_SETFPREGS: 564 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); 565 break; 566 case PT_SETDBREGS: 567 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); 568 break; 569 case PT_IO: 570 error = COPYIN(uap->addr, &r.piod, sizeof r.piod); 571 break; 572 case PT_VM_ENTRY: 573 error = COPYIN(uap->addr, &r.pve, sizeof r.pve); 574 break; 575 default: 576 addr = uap->addr; 577 break; 578 } 579 if (error) 580 return (error); 581 582 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 583 if (error) 584 return (error); 585 586 switch (uap->req) { 587 case PT_VM_ENTRY: 588 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve); 589 break; 590 case PT_IO: 591 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); 592 break; 593 case PT_GETREGS: 594 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); 595 break; 596 case PT_GETFPREGS: 597 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); 598 break; 599 case PT_GETDBREGS: 600 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); 601 break; 602 case PT_LWPINFO: 603 error = copyout(&r.pl, uap->addr, uap->data); 604 break; 605 } 606 607 return (error); 608} 609#undef COPYIN 610#undef COPYOUT 611 612#ifdef COMPAT_FREEBSD32 613/* 614 * PROC_READ(regs, td2, addr); 615 * becomes either: 616 * proc_read_regs(td2, addr); 617 * or 618 * proc_read_regs32(td2, addr); 619 * .. except this is done at runtime. There is an additional 620 * complication in that PROC_WRITE disallows 32 bit consumers 621 * from writing to 64 bit address space targets. 622 */ 623#define PROC_READ(w, t, a) wrap32 ? \ 624 proc_read_ ## w ## 32(t, a) : \ 625 proc_read_ ## w (t, a) 626#define PROC_WRITE(w, t, a) wrap32 ? \ 627 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 628 proc_write_ ## w (t, a) 629#else 630#define PROC_READ(w, t, a) proc_read_ ## w (t, a) 631#define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 632#endif 633 634int 635kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 636{ 637 struct iovec iov; 638 struct uio uio; 639 struct proc *curp, *p, *pp; 640 struct thread *td2 = NULL; 641 struct ptrace_io_desc *piod = NULL; 642 struct ptrace_lwpinfo *pl; 643 int error, write, tmp, num; 644 int proctree_locked = 0; 645 lwpid_t tid = 0, *buf; 646#ifdef COMPAT_FREEBSD32 647 int wrap32 = 0, safe = 0; 648 struct ptrace_io_desc32 *piod32 = NULL; 649 struct ptrace_lwpinfo32 *pl32 = NULL; 650 struct ptrace_lwpinfo plr; 651#endif 652 653 curp = td->td_proc; 654 655 /* Lock proctree before locking the process. */ 656 switch (req) { 657 case PT_TRACE_ME: 658 case PT_ATTACH: 659 case PT_STEP: 660 case PT_CONTINUE: 661 case PT_TO_SCE: 662 case PT_TO_SCX: 663 case PT_SYSCALL: 664 case PT_FOLLOW_FORK: 665 case PT_DETACH: 666 sx_xlock(&proctree_lock); 667 proctree_locked = 1; 668 break; 669 default: 670 break; 671 } 672 673 write = 0; 674 if (req == PT_TRACE_ME) { 675 p = td->td_proc; 676 PROC_LOCK(p); 677 } else { 678 if (pid <= PID_MAX) { 679 if ((p = pfind(pid)) == NULL) { 680 if (proctree_locked) 681 sx_xunlock(&proctree_lock); 682 return (ESRCH); 683 } 684 } else { 685 td2 = tdfind(pid, -1); 686 if (td2 == NULL) { 687 if (proctree_locked) 688 sx_xunlock(&proctree_lock); 689 return (ESRCH); 690 } 691 p = td2->td_proc; 692 tid = pid; 693 pid = p->p_pid; 694 } 695 } 696 AUDIT_ARG_PROCESS(p); 697 698 if ((p->p_flag & P_WEXIT) != 0) { 699 error = ESRCH; 700 goto fail; 701 } 702 if ((error = p_cansee(td, p)) != 0) 703 goto fail; 704 705 if ((error = p_candebug(td, p)) != 0) 706 goto fail; 707 708 /* 709 * System processes can't be debugged. 710 */ 711 if ((p->p_flag & P_SYSTEM) != 0) { 712 error = EINVAL; 713 goto fail; 714 } 715 716 if (tid == 0) { 717 if ((p->p_flag & P_STOPPED_TRACE) != 0) { 718 KASSERT(p->p_xthread != NULL, ("NULL p_xthread")); 719 td2 = p->p_xthread; 720 } else { 721 td2 = FIRST_THREAD_IN_PROC(p); 722 } 723 tid = td2->td_tid; 724 } 725 726#ifdef COMPAT_FREEBSD32 727 /* 728 * Test if we're a 32 bit client and what the target is. 729 * Set the wrap controls accordingly. 730 */ 731 if (SV_CURPROC_FLAG(SV_ILP32)) { 732 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32)) 733 safe = 1; 734 wrap32 = 1; 735 } 736#endif 737 /* 738 * Permissions check 739 */ 740 switch (req) { 741 case PT_TRACE_ME: 742 /* Always legal. */ 743 break; 744 745 case PT_ATTACH: 746 /* Self */ 747 if (p->p_pid == td->td_proc->p_pid) { 748 error = EINVAL; 749 goto fail; 750 } 751 752 /* Already traced */ 753 if (p->p_flag & P_TRACED) { 754 error = EBUSY; 755 goto fail; 756 } 757 758 /* Can't trace an ancestor if you're being traced. */ 759 if (curp->p_flag & P_TRACED) { 760 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 761 if (pp == p) { 762 error = EINVAL; 763 goto fail; 764 } 765 } 766 } 767 768 769 /* OK */ 770 break; 771 772 case PT_CLEARSTEP: 773 /* Allow thread to clear single step for itself */ 774 if (td->td_tid == tid) 775 break; 776 777 /* FALLTHROUGH */ 778 default: 779 /* not being traced... */ 780 if ((p->p_flag & P_TRACED) == 0) { 781 error = EPERM; 782 goto fail; 783 } 784 785 /* not being traced by YOU */ 786 if (p->p_pptr != td->td_proc) { 787 error = EBUSY; 788 goto fail; 789 } 790 791 /* not currently stopped */ 792 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 || 793 p->p_suspcount != p->p_numthreads || 794 (p->p_flag & P_WAITED) == 0) { 795 error = EBUSY; 796 goto fail; 797 } 798 799 if ((p->p_flag & P_STOPPED_TRACE) == 0) { 800 static int count = 0; 801 if (count++ == 0) 802 printf("P_STOPPED_TRACE not set.\n"); 803 } 804 805 /* OK */ 806 break; 807 } 808 809 /* Keep this process around until we finish this request. */ 810 _PHOLD(p); 811 812#ifdef FIX_SSTEP 813 /* 814 * Single step fixup ala procfs 815 */ 816 FIX_SSTEP(td2); 817#endif 818 819 /* 820 * Actually do the requests 821 */ 822 823 td->td_retval[0] = 0; 824 825 switch (req) { 826 case PT_TRACE_ME: 827 /* set my trace flag and "owner" so it can read/write me */ 828 p->p_flag |= P_TRACED; 829 if (p->p_flag & P_PPWAIT) 830 p->p_flag |= P_PPTRACE; 831 p->p_oppid = p->p_pptr->p_pid; 832 break; 833 834 case PT_ATTACH: 835 /* security check done above */ 836 /* 837 * It would be nice if the tracing relationship was separate 838 * from the parent relationship but that would require 839 * another set of links in the proc struct or for "wait" 840 * to scan the entire proc table. To make life easier, 841 * we just re-parent the process we're trying to trace. 842 * The old parent is remembered so we can put things back 843 * on a "detach". 844 */ 845 p->p_flag |= P_TRACED; 846 p->p_oppid = p->p_pptr->p_pid; 847 if (p->p_pptr != td->td_proc) { 848 proc_reparent(p, td->td_proc); 849 } 850 data = SIGSTOP; 851 goto sendsig; /* in PT_CONTINUE below */ 852 853 case PT_CLEARSTEP: 854 error = ptrace_clear_single_step(td2); 855 break; 856 857 case PT_SETSTEP: 858 error = ptrace_single_step(td2); 859 break; 860 861 case PT_SUSPEND: 862 td2->td_dbgflags |= TDB_SUSPEND; 863 thread_lock(td2); 864 td2->td_flags |= TDF_NEEDSUSPCHK; 865 thread_unlock(td2); 866 break; 867 868 case PT_RESUME: 869 td2->td_dbgflags &= ~TDB_SUSPEND; 870 break; 871 872 case PT_FOLLOW_FORK: 873 if (data) 874 p->p_flag |= P_FOLLOWFORK; 875 else 876 p->p_flag &= ~P_FOLLOWFORK; 877 break; 878 879 case PT_STEP: 880 case PT_CONTINUE: 881 case PT_TO_SCE: 882 case PT_TO_SCX: 883 case PT_SYSCALL: 884 case PT_DETACH: 885 /* Zero means do not send any signal */ 886 if (data < 0 || data > _SIG_MAXSIG) { 887 error = EINVAL; 888 break; 889 } 890 891 switch (req) { 892 case PT_STEP: 893 error = ptrace_single_step(td2); 894 if (error) 895 goto out; 896 break; 897 case PT_CONTINUE: 898 case PT_TO_SCE: 899 case PT_TO_SCX: 900 case PT_SYSCALL: 901 if (addr != (void *)1) { 902 error = ptrace_set_pc(td2, 903 (u_long)(uintfptr_t)addr); 904 if (error) 905 goto out; 906 } 907 switch (req) { 908 case PT_TO_SCE: 909 p->p_stops |= S_PT_SCE; 910 break; 911 case PT_TO_SCX: 912 p->p_stops |= S_PT_SCX; 913 break; 914 case PT_SYSCALL: 915 p->p_stops |= S_PT_SCE | S_PT_SCX; 916 break; 917 } 918 break; 919 case PT_DETACH: 920 /* reset process parent */ 921 if (p->p_oppid != p->p_pptr->p_pid) { 922 struct proc *pp; 923 924 PROC_LOCK(p->p_pptr); 925 sigqueue_take(p->p_ksi); 926 PROC_UNLOCK(p->p_pptr); 927 928 PROC_UNLOCK(p); 929 pp = pfind(p->p_oppid); 930 if (pp == NULL) 931 pp = initproc; 932 else 933 PROC_UNLOCK(pp); 934 PROC_LOCK(p); 935 proc_reparent(p, pp); 936 if (pp == initproc) 937 p->p_sigparent = SIGCHLD; 938 } 939 p->p_oppid = 0; 940 p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK); 941 942 /* should we send SIGCHLD? */ 943 /* childproc_continued(p); */ 944 break; 945 } 946 947 sendsig: 948 if (proctree_locked) { 949 sx_xunlock(&proctree_lock); 950 proctree_locked = 0; 951 } 952 p->p_xstat = data; 953 p->p_xthread = NULL; 954 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) { 955 /* deliver or queue signal */ 956 td2->td_dbgflags &= ~TDB_XSIG; 957 td2->td_xsig = data; 958 959 if (req == PT_DETACH) { 960 struct thread *td3; 961 FOREACH_THREAD_IN_PROC(p, td3) { 962 td3->td_dbgflags &= ~TDB_SUSPEND; 963 } 964 } 965 /* 966 * unsuspend all threads, to not let a thread run, 967 * you should use PT_SUSPEND to suspend it before 968 * continuing process. 969 */ 970 PROC_SLOCK(p); 971 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED); 972 thread_unsuspend(p); 973 PROC_SUNLOCK(p); 974 } else { 975 if (data) 976 kern_psignal(p, data); 977 } 978 break; 979 980 case PT_WRITE_I: 981 case PT_WRITE_D: 982 td2->td_dbgflags |= TDB_USERWR; 983 write = 1; 984 /* FALLTHROUGH */ 985 case PT_READ_I: 986 case PT_READ_D: 987 PROC_UNLOCK(p); 988 tmp = 0; 989 /* write = 0 set above */ 990 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 991 iov.iov_len = sizeof(int); 992 uio.uio_iov = &iov; 993 uio.uio_iovcnt = 1; 994 uio.uio_offset = (off_t)(uintptr_t)addr; 995 uio.uio_resid = sizeof(int); 996 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */ 997 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 998 uio.uio_td = td; 999 error = proc_rwmem(p, &uio); 1000 if (uio.uio_resid != 0) { 1001 /* 1002 * XXX proc_rwmem() doesn't currently return ENOSPC, 1003 * so I think write() can bogusly return 0. 1004 * XXX what happens for short writes? We don't want 1005 * to write partial data. 1006 * XXX proc_rwmem() returns EPERM for other invalid 1007 * addresses. Convert this to EINVAL. Does this 1008 * clobber returns of EPERM for other reasons? 1009 */ 1010 if (error == 0 || error == ENOSPC || error == EPERM) 1011 error = EINVAL; /* EOF */ 1012 } 1013 if (!write) 1014 td->td_retval[0] = tmp; 1015 PROC_LOCK(p); 1016 break; 1017 1018 case PT_IO: 1019#ifdef COMPAT_FREEBSD32 1020 if (wrap32) { 1021 piod32 = addr; 1022 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; 1023 iov.iov_len = piod32->piod_len; 1024 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; 1025 uio.uio_resid = piod32->piod_len; 1026 } else 1027#endif 1028 { 1029 piod = addr; 1030 iov.iov_base = piod->piod_addr; 1031 iov.iov_len = piod->piod_len; 1032 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 1033 uio.uio_resid = piod->piod_len; 1034 } 1035 uio.uio_iov = &iov; 1036 uio.uio_iovcnt = 1; 1037 uio.uio_segflg = UIO_USERSPACE; 1038 uio.uio_td = td; 1039#ifdef COMPAT_FREEBSD32 1040 tmp = wrap32 ? piod32->piod_op : piod->piod_op; 1041#else 1042 tmp = piod->piod_op; 1043#endif 1044 switch (tmp) { 1045 case PIOD_READ_D: 1046 case PIOD_READ_I: 1047 uio.uio_rw = UIO_READ; 1048 break; 1049 case PIOD_WRITE_D: 1050 case PIOD_WRITE_I: 1051 td2->td_dbgflags |= TDB_USERWR; 1052 uio.uio_rw = UIO_WRITE; 1053 break; 1054 default: 1055 error = EINVAL; 1056 goto out; 1057 } 1058 PROC_UNLOCK(p); 1059 error = proc_rwmem(p, &uio); 1060#ifdef COMPAT_FREEBSD32 1061 if (wrap32) 1062 piod32->piod_len -= uio.uio_resid; 1063 else 1064#endif 1065 piod->piod_len -= uio.uio_resid; 1066 PROC_LOCK(p); 1067 break; 1068 1069 case PT_KILL: 1070 data = SIGKILL; 1071 goto sendsig; /* in PT_CONTINUE above */ 1072 1073 case PT_SETREGS: 1074 td2->td_dbgflags |= TDB_USERWR; 1075 error = PROC_WRITE(regs, td2, addr); 1076 break; 1077 1078 case PT_GETREGS: 1079 error = PROC_READ(regs, td2, addr); 1080 break; 1081 1082 case PT_SETFPREGS: 1083 td2->td_dbgflags |= TDB_USERWR; 1084 error = PROC_WRITE(fpregs, td2, addr); 1085 break; 1086 1087 case PT_GETFPREGS: 1088 error = PROC_READ(fpregs, td2, addr); 1089 break; 1090 1091 case PT_SETDBREGS: 1092 td2->td_dbgflags |= TDB_USERWR; 1093 error = PROC_WRITE(dbregs, td2, addr); 1094 break; 1095 1096 case PT_GETDBREGS: 1097 error = PROC_READ(dbregs, td2, addr); 1098 break; 1099 1100 case PT_LWPINFO: 1101 if (data <= 0 || 1102#ifdef COMPAT_FREEBSD32 1103 (!wrap32 && data > sizeof(*pl)) || 1104 (wrap32 && data > sizeof(*pl32))) { 1105#else 1106 data > sizeof(*pl)) { 1107#endif 1108 error = EINVAL; 1109 break; 1110 } 1111#ifdef COMPAT_FREEBSD32 1112 if (wrap32) { 1113 pl = &plr; 1114 pl32 = addr; 1115 } else 1116#endif 1117 pl = addr; 1118 pl->pl_lwpid = td2->td_tid; 1119 pl->pl_event = PL_EVENT_NONE; 1120 pl->pl_flags = 0; 1121 if (td2->td_dbgflags & TDB_XSIG) { 1122 pl->pl_event = PL_EVENT_SIGNAL; 1123 if (td2->td_dbgksi.ksi_signo != 0 && 1124#ifdef COMPAT_FREEBSD32 1125 ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo, 1126 pl_siginfo) + sizeof(pl->pl_siginfo)) || 1127 (wrap32 && data >= offsetof(struct ptrace_lwpinfo32, 1128 pl_siginfo) + sizeof(struct siginfo32))) 1129#else 1130 data >= offsetof(struct ptrace_lwpinfo, pl_siginfo) 1131 + sizeof(pl->pl_siginfo) 1132#endif 1133 ){ 1134 pl->pl_flags |= PL_FLAG_SI; 1135 pl->pl_siginfo = td2->td_dbgksi.ksi_info; 1136 } 1137 } 1138 if ((pl->pl_flags & PL_FLAG_SI) == 0) 1139 bzero(&pl->pl_siginfo, sizeof(pl->pl_siginfo)); 1140 if (td2->td_dbgflags & TDB_SCE) 1141 pl->pl_flags |= PL_FLAG_SCE; 1142 else if (td2->td_dbgflags & TDB_SCX) 1143 pl->pl_flags |= PL_FLAG_SCX; 1144 if (td2->td_dbgflags & TDB_EXEC) 1145 pl->pl_flags |= PL_FLAG_EXEC; 1146 if (td2->td_dbgflags & TDB_FORK) { 1147 pl->pl_flags |= PL_FLAG_FORKED; 1148 pl->pl_child_pid = td2->td_dbg_forked; 1149 } 1150 if (td2->td_dbgflags & TDB_CHILD) 1151 pl->pl_flags |= PL_FLAG_CHILD; 1152 pl->pl_sigmask = td2->td_sigmask; 1153 pl->pl_siglist = td2->td_siglist; 1154 strcpy(pl->pl_tdname, td2->td_name); 1155#ifdef COMPAT_FREEBSD32 1156 if (wrap32) 1157 ptrace_lwpinfo_to32(pl, pl32); 1158#endif 1159 break; 1160 1161 case PT_GETNUMLWPS: 1162 td->td_retval[0] = p->p_numthreads; 1163 break; 1164 1165 case PT_GETLWPLIST: 1166 if (data <= 0) { 1167 error = EINVAL; 1168 break; 1169 } 1170 num = imin(p->p_numthreads, data); 1171 PROC_UNLOCK(p); 1172 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 1173 tmp = 0; 1174 PROC_LOCK(p); 1175 FOREACH_THREAD_IN_PROC(p, td2) { 1176 if (tmp >= num) 1177 break; 1178 buf[tmp++] = td2->td_tid; 1179 } 1180 PROC_UNLOCK(p); 1181 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 1182 free(buf, M_TEMP); 1183 if (!error) 1184 td->td_retval[0] = tmp; 1185 PROC_LOCK(p); 1186 break; 1187 1188 case PT_VM_TIMESTAMP: 1189 td->td_retval[0] = p->p_vmspace->vm_map.timestamp; 1190 break; 1191 1192 case PT_VM_ENTRY: 1193 PROC_UNLOCK(p); 1194#ifdef COMPAT_FREEBSD32 1195 if (wrap32) 1196 error = ptrace_vm_entry32(td, p, addr); 1197 else 1198#endif 1199 error = ptrace_vm_entry(td, p, addr); 1200 PROC_LOCK(p); 1201 break; 1202 1203 default: 1204#ifdef __HAVE_PTRACE_MACHDEP 1205 if (req >= PT_FIRSTMACH) { 1206 PROC_UNLOCK(p); 1207 error = cpu_ptrace(td2, req, addr, data); 1208 PROC_LOCK(p); 1209 } else 1210#endif 1211 /* Unknown request. */ 1212 error = EINVAL; 1213 break; 1214 } 1215 1216out: 1217 /* Drop our hold on this process now that the request has completed. */ 1218 _PRELE(p); 1219fail: 1220 PROC_UNLOCK(p); 1221 if (proctree_locked) 1222 sx_xunlock(&proctree_lock); 1223 return (error); 1224} 1225#undef PROC_READ 1226#undef PROC_WRITE 1227 1228/* 1229 * Stop a process because of a debugging event; 1230 * stay stopped until p->p_step is cleared 1231 * (cleared by PIOCCONT in procfs). 1232 */ 1233void 1234stopevent(struct proc *p, unsigned int event, unsigned int val) 1235{ 1236 1237 PROC_LOCK_ASSERT(p, MA_OWNED); 1238 p->p_step = 1; 1239 do { 1240 p->p_xstat = val; 1241 p->p_xthread = NULL; 1242 p->p_stype = event; /* Which event caused the stop? */ 1243 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ 1244 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); 1245 } while (p->p_step); 1246} 1247 1248static int 1249protect_setchild(struct thread *td, struct proc *p, int flags) 1250{ 1251 1252 PROC_LOCK_ASSERT(p, MA_OWNED); 1253 if (p->p_flag & P_SYSTEM || p_cansee(td, p) != 0) 1254 return (0); 1255 if (flags & PPROT_SET) { 1256 p->p_flag |= P_PROTECTED; 1257 if (flags & PPROT_INHERIT) 1258 p->p_flag2 |= P2_INHERIT_PROTECTED; 1259 } else { 1260 p->p_flag &= ~P_PROTECTED; 1261 p->p_flag2 &= ~P2_INHERIT_PROTECTED; 1262 } 1263 return (1); 1264} 1265 1266static int 1267protect_setchildren(struct thread *td, struct proc *top, int flags) 1268{ 1269 struct proc *p; 1270 int ret; 1271 1272 p = top; 1273 ret = 0; 1274 sx_assert(&proctree_lock, SX_LOCKED); 1275 for (;;) { 1276 ret |= protect_setchild(td, p, flags); 1277 PROC_UNLOCK(p); 1278 /* 1279 * If this process has children, descend to them next, 1280 * otherwise do any siblings, and if done with this level, 1281 * follow back up the tree (but not past top). 1282 */ 1283 if (!LIST_EMPTY(&p->p_children)) 1284 p = LIST_FIRST(&p->p_children); 1285 else for (;;) { 1286 if (p == top) { 1287 PROC_LOCK(p); 1288 return (ret); 1289 } 1290 if (LIST_NEXT(p, p_sibling)) { 1291 p = LIST_NEXT(p, p_sibling); 1292 break; 1293 } 1294 p = p->p_pptr; 1295 } 1296 PROC_LOCK(p); 1297 } 1298} 1299 1300static int 1301protect_set(struct thread *td, struct proc *p, int flags) 1302{ 1303 int error, ret; 1304 1305 switch (PPROT_OP(flags)) { 1306 case PPROT_SET: 1307 case PPROT_CLEAR: 1308 break; 1309 default: 1310 return (EINVAL); 1311 } 1312 1313 if ((PPROT_FLAGS(flags) & ~(PPROT_DESCEND | PPROT_INHERIT)) != 0) 1314 return (EINVAL); 1315 1316 error = priv_check(td, PRIV_VM_MADV_PROTECT); 1317 if (error) 1318 return (error); 1319 1320 if (flags & PPROT_DESCEND) 1321 ret = protect_setchildren(td, p, flags); 1322 else 1323 ret = protect_setchild(td, p, flags); 1324 if (ret == 0) 1325 return (EPERM); 1326 return (0); 1327} 1328 1329#ifndef _SYS_SYSPROTO_H_ 1330struct procctl_args { 1331 idtype_t idtype; 1332 id_t id; 1333 int com; 1334 void *data; 1335}; 1336#endif 1337/* ARGSUSED */ 1338int 1339sys_procctl(struct thread *td, struct procctl_args *uap) 1340{ 1341 int error, flags; 1342 void *data; 1343 1344 switch (uap->com) { 1345 case PROC_SPROTECT: 1346 error = copyin(uap->data, &flags, sizeof(flags)); 1347 if (error) 1348 return (error); 1349 data = &flags; 1350 break; 1351 default: 1352 return (EINVAL); 1353 } 1354 1355 return (kern_procctl(td, uap->idtype, uap->id, uap->com, data)); 1356} 1357 1358static int 1359kern_procctl_single(struct thread *td, struct proc *p, int com, void *data) 1360{ 1361 1362 PROC_LOCK_ASSERT(p, MA_OWNED); 1363 switch (com) { 1364 case PROC_SPROTECT: 1365 return (protect_set(td, p, *(int *)data)); 1366 default: 1367 return (EINVAL); 1368 } 1369} 1370 1371int 1372kern_procctl(struct thread *td, idtype_t idtype, id_t id, int com, void *data) 1373{ 1374 struct pgrp *pg; 1375 struct proc *p; 1376 int error, first_error, ok; 1377 1378 sx_slock(&proctree_lock); 1379 switch (idtype) { 1380 case P_PID: 1381 p = pfind(id); 1382 if (p == NULL) { 1383 error = ESRCH; 1384 break; 1385 } 1386 if (p->p_state == PRS_NEW) 1387 error = ESRCH; 1388 else 1389 error = p_cansee(td, p); 1390 if (error == 0) 1391 error = kern_procctl_single(td, p, com, data); 1392 PROC_UNLOCK(p); 1393 break; 1394 case P_PGID: 1395 /* 1396 * Attempt to apply the operation to all members of the 1397 * group. Ignore processes in the group that can't be 1398 * seen. Ignore errors so long as at least one process is 1399 * able to complete the request successfully. 1400 */ 1401 pg = pgfind(id); 1402 if (pg == NULL) { 1403 error = ESRCH; 1404 break; 1405 } 1406 PGRP_UNLOCK(pg); 1407 ok = 0; 1408 first_error = 0; 1409 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 1410 PROC_LOCK(p); 1411 if (p->p_state == PRS_NEW || p_cansee(td, p) != 0) { 1412 PROC_UNLOCK(p); 1413 continue; 1414 } 1415 error = kern_procctl_single(td, p, com, data); 1416 PROC_UNLOCK(p); 1417 if (error == 0) 1418 ok = 1; 1419 else if (first_error == 0) 1420 first_error = error; 1421 } 1422 if (ok) 1423 error = 0; 1424 else if (first_error != 0) 1425 error = first_error; 1426 else 1427 /* 1428 * Was not able to see any processes in the 1429 * process group. 1430 */ 1431 error = ESRCH; 1432 break; 1433 default: 1434 error = EINVAL; 1435 break; 1436 } 1437 sx_sunlock(&proctree_lock); 1438 return (error); 1439} 1440