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: releng/10.3/sys/kern/sys_process.c 325871 2017-11-15 22:40:46Z gordon $"); 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/vnode.h> 47#include <sys/ptrace.h> 48#include <sys/rwlock.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_param.h> 65 66#ifdef COMPAT_FREEBSD32 67#include <sys/procfs.h> 68#include <compat/freebsd32/freebsd32_signal.h> 69 70struct ptrace_io_desc32 { 71 int piod_op; 72 uint32_t piod_offs; 73 uint32_t piod_addr; 74 uint32_t piod_len; 75}; 76 77struct ptrace_vm_entry32 { 78 int pve_entry; 79 int pve_timestamp; 80 uint32_t pve_start; 81 uint32_t pve_end; 82 uint32_t pve_offset; 83 u_int pve_prot; 84 u_int pve_pathlen; 85 int32_t pve_fileid; 86 u_int pve_fsid; 87 uint32_t pve_path; 88}; 89 90struct ptrace_lwpinfo32 { 91 lwpid_t pl_lwpid; /* LWP described. */ 92 int pl_event; /* Event that stopped the LWP. */ 93 int pl_flags; /* LWP flags. */ 94 sigset_t pl_sigmask; /* LWP signal mask */ 95 sigset_t pl_siglist; /* LWP pending signal */ 96 struct siginfo32 pl_siginfo; /* siginfo for signal */ 97 char pl_tdname[MAXCOMLEN + 1]; /* LWP name. */ 98 pid_t pl_child_pid; /* New child pid */ 99 u_int pl_syscall_code; 100 u_int pl_syscall_narg; 101}; 102 103#endif 104 105/* 106 * Functions implemented using PROC_ACTION(): 107 * 108 * proc_read_regs(proc, regs) 109 * Get the current user-visible register set from the process 110 * and copy it into the regs structure (<machine/reg.h>). 111 * The process is stopped at the time read_regs is called. 112 * 113 * proc_write_regs(proc, regs) 114 * Update the current register set from the passed in regs 115 * structure. Take care to avoid clobbering special CPU 116 * registers or privileged bits in the PSL. 117 * Depending on the architecture this may have fix-up work to do, 118 * especially if the IAR or PCW are modified. 119 * The process is stopped at the time write_regs is called. 120 * 121 * proc_read_fpregs, proc_write_fpregs 122 * deal with the floating point register set, otherwise as above. 123 * 124 * proc_read_dbregs, proc_write_dbregs 125 * deal with the processor debug register set, otherwise as above. 126 * 127 * proc_sstep(proc) 128 * Arrange for the process to trap after executing a single instruction. 129 */ 130 131#define PROC_ACTION(action) do { \ 132 int error; \ 133 \ 134 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ 135 if ((td->td_proc->p_flag & P_INMEM) == 0) \ 136 error = EIO; \ 137 else \ 138 error = (action); \ 139 return (error); \ 140} while(0) 141 142int 143proc_read_regs(struct thread *td, struct reg *regs) 144{ 145 146 PROC_ACTION(fill_regs(td, regs)); 147} 148 149int 150proc_write_regs(struct thread *td, struct reg *regs) 151{ 152 153 PROC_ACTION(set_regs(td, regs)); 154} 155 156int 157proc_read_dbregs(struct thread *td, struct dbreg *dbregs) 158{ 159 160 PROC_ACTION(fill_dbregs(td, dbregs)); 161} 162 163int 164proc_write_dbregs(struct thread *td, struct dbreg *dbregs) 165{ 166 167 PROC_ACTION(set_dbregs(td, dbregs)); 168} 169 170/* 171 * Ptrace doesn't support fpregs at all, and there are no security holes 172 * or translations for fpregs, so we can just copy them. 173 */ 174int 175proc_read_fpregs(struct thread *td, struct fpreg *fpregs) 176{ 177 178 PROC_ACTION(fill_fpregs(td, fpregs)); 179} 180 181int 182proc_write_fpregs(struct thread *td, struct fpreg *fpregs) 183{ 184 185 PROC_ACTION(set_fpregs(td, fpregs)); 186} 187 188#ifdef COMPAT_FREEBSD32 189/* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 190int 191proc_read_regs32(struct thread *td, struct reg32 *regs32) 192{ 193 194 PROC_ACTION(fill_regs32(td, regs32)); 195} 196 197int 198proc_write_regs32(struct thread *td, struct reg32 *regs32) 199{ 200 201 PROC_ACTION(set_regs32(td, regs32)); 202} 203 204int 205proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 206{ 207 208 PROC_ACTION(fill_dbregs32(td, dbregs32)); 209} 210 211int 212proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 213{ 214 215 PROC_ACTION(set_dbregs32(td, dbregs32)); 216} 217 218int 219proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 220{ 221 222 PROC_ACTION(fill_fpregs32(td, fpregs32)); 223} 224 225int 226proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 227{ 228 229 PROC_ACTION(set_fpregs32(td, fpregs32)); 230} 231#endif 232 233int 234proc_sstep(struct thread *td) 235{ 236 237 PROC_ACTION(ptrace_single_step(td)); 238} 239 240int 241proc_rwmem(struct proc *p, struct uio *uio) 242{ 243 vm_map_t map; 244 vm_offset_t pageno; /* page number */ 245 vm_prot_t reqprot; 246 int error, fault_flags, page_offset, writing; 247 248 /* 249 * Assert that someone has locked this vmspace. (Should be 250 * curthread but we can't assert that.) This keeps the process 251 * from exiting out from under us until this operation completes. 252 */ 253 KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__, 254 p, p->p_pid)); 255 256 /* 257 * The map we want... 258 */ 259 map = &p->p_vmspace->vm_map; 260 261 /* 262 * If we are writing, then we request vm_fault() to create a private 263 * copy of each page. Since these copies will not be writeable by the 264 * process, we must explicity request that they be dirtied. 265 */ 266 writing = uio->uio_rw == UIO_WRITE; 267 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ; 268 fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 269 270 /* 271 * Only map in one page at a time. We don't have to, but it 272 * makes things easier. This way is trivial - right? 273 */ 274 do { 275 vm_offset_t uva; 276 u_int len; 277 vm_page_t m; 278 279 uva = (vm_offset_t)uio->uio_offset; 280 281 /* 282 * Get the page number of this segment. 283 */ 284 pageno = trunc_page(uva); 285 page_offset = uva - pageno; 286 287 /* 288 * How many bytes to copy 289 */ 290 len = min(PAGE_SIZE - page_offset, uio->uio_resid); 291 292 /* 293 * Fault and hold the page on behalf of the process. 294 */ 295 error = vm_fault_hold(map, pageno, reqprot, fault_flags, &m); 296 if (error != KERN_SUCCESS) { 297 if (error == KERN_RESOURCE_SHORTAGE) 298 error = ENOMEM; 299 else 300 error = EFAULT; 301 break; 302 } 303 304 /* 305 * Now do the i/o move. 306 */ 307 error = uiomove_fromphys(&m, page_offset, len, uio); 308 309 /* Make the I-cache coherent for breakpoints. */ 310 if (writing && error == 0) { 311 vm_map_lock_read(map); 312 if (vm_map_check_protection(map, pageno, pageno + 313 PAGE_SIZE, VM_PROT_EXECUTE)) 314 vm_sync_icache(map, uva, len); 315 vm_map_unlock_read(map); 316 } 317 318 /* 319 * Release the page. 320 */ 321 vm_page_lock(m); 322 vm_page_unhold(m); 323 vm_page_unlock(m); 324 325 } while (error == 0 && uio->uio_resid > 0); 326 327 return (error); 328} 329 330static int 331ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve) 332{ 333 struct vattr vattr; 334 vm_map_t map; 335 vm_map_entry_t entry; 336 vm_object_t obj, tobj, lobj; 337 struct vmspace *vm; 338 struct vnode *vp; 339 char *freepath, *fullpath; 340 u_int pathlen; 341 int error, index; 342 343 error = 0; 344 obj = NULL; 345 346 vm = vmspace_acquire_ref(p); 347 map = &vm->vm_map; 348 vm_map_lock_read(map); 349 350 do { 351 entry = map->header.next; 352 index = 0; 353 while (index < pve->pve_entry && entry != &map->header) { 354 entry = entry->next; 355 index++; 356 } 357 if (index != pve->pve_entry) { 358 error = EINVAL; 359 break; 360 } 361 while (entry != &map->header && 362 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) { 363 entry = entry->next; 364 index++; 365 } 366 if (entry == &map->header) { 367 error = ENOENT; 368 break; 369 } 370 371 /* We got an entry. */ 372 pve->pve_entry = index + 1; 373 pve->pve_timestamp = map->timestamp; 374 pve->pve_start = entry->start; 375 pve->pve_end = entry->end - 1; 376 pve->pve_offset = entry->offset; 377 pve->pve_prot = entry->protection; 378 379 /* Backing object's path needed? */ 380 if (pve->pve_pathlen == 0) 381 break; 382 383 pathlen = pve->pve_pathlen; 384 pve->pve_pathlen = 0; 385 386 obj = entry->object.vm_object; 387 if (obj != NULL) 388 VM_OBJECT_RLOCK(obj); 389 } while (0); 390 391 vm_map_unlock_read(map); 392 vmspace_free(vm); 393 394 pve->pve_fsid = VNOVAL; 395 pve->pve_fileid = VNOVAL; 396 397 if (error == 0 && obj != NULL) { 398 lobj = obj; 399 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 400 if (tobj != obj) 401 VM_OBJECT_RLOCK(tobj); 402 if (lobj != obj) 403 VM_OBJECT_RUNLOCK(lobj); 404 lobj = tobj; 405 pve->pve_offset += tobj->backing_object_offset; 406 } 407 vp = vm_object_vnode(lobj); 408 if (vp != NULL) 409 vref(vp); 410 if (lobj != obj) 411 VM_OBJECT_RUNLOCK(lobj); 412 VM_OBJECT_RUNLOCK(obj); 413 414 if (vp != NULL) { 415 freepath = NULL; 416 fullpath = NULL; 417 vn_fullpath(td, vp, &fullpath, &freepath); 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); 424 425 if (fullpath != NULL) { 426 pve->pve_pathlen = strlen(fullpath) + 1; 427 if (pve->pve_pathlen <= pathlen) { 428 error = copyout(fullpath, pve->pve_path, 429 pve->pve_pathlen); 430 } else 431 error = ENAMETOOLONG; 432 } 433 if (freepath != NULL) 434 free(freepath, M_TEMP); 435 } 436 } 437 if (error == 0) 438 CTR3(KTR_PTRACE, "PT_VM_ENTRY: pid %d, entry %d, start %p", 439 p->p_pid, pve->pve_entry, pve->pve_start); 440 441 return (error); 442} 443 444#ifdef COMPAT_FREEBSD32 445static int 446ptrace_vm_entry32(struct thread *td, struct proc *p, 447 struct ptrace_vm_entry32 *pve32) 448{ 449 struct ptrace_vm_entry pve; 450 int error; 451 452 pve.pve_entry = pve32->pve_entry; 453 pve.pve_pathlen = pve32->pve_pathlen; 454 pve.pve_path = (void *)(uintptr_t)pve32->pve_path; 455 456 error = ptrace_vm_entry(td, p, &pve); 457 if (error == 0) { 458 pve32->pve_entry = pve.pve_entry; 459 pve32->pve_timestamp = pve.pve_timestamp; 460 pve32->pve_start = pve.pve_start; 461 pve32->pve_end = pve.pve_end; 462 pve32->pve_offset = pve.pve_offset; 463 pve32->pve_prot = pve.pve_prot; 464 pve32->pve_fileid = pve.pve_fileid; 465 pve32->pve_fsid = pve.pve_fsid; 466 } 467 468 pve32->pve_pathlen = pve.pve_pathlen; 469 return (error); 470} 471 472static void 473ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl, 474 struct ptrace_lwpinfo32 *pl32) 475{ 476 477 bzero(pl32, sizeof(*pl32)); 478 pl32->pl_lwpid = pl->pl_lwpid; 479 pl32->pl_event = pl->pl_event; 480 pl32->pl_flags = pl->pl_flags; 481 pl32->pl_sigmask = pl->pl_sigmask; 482 pl32->pl_siglist = pl->pl_siglist; 483 siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo); 484 strcpy(pl32->pl_tdname, pl->pl_tdname); 485 pl32->pl_child_pid = pl->pl_child_pid; 486 pl32->pl_syscall_code = pl->pl_syscall_code; 487 pl32->pl_syscall_narg = pl->pl_syscall_narg; 488} 489#endif /* COMPAT_FREEBSD32 */ 490 491/* 492 * Process debugging system call. 493 */ 494#ifndef _SYS_SYSPROTO_H_ 495struct ptrace_args { 496 int req; 497 pid_t pid; 498 caddr_t addr; 499 int data; 500}; 501#endif 502 503#ifdef COMPAT_FREEBSD32 504/* 505 * This CPP subterfuge is to try and reduce the number of ifdefs in 506 * the body of the code. 507 * COPYIN(uap->addr, &r.reg, sizeof r.reg); 508 * becomes either: 509 * copyin(uap->addr, &r.reg, sizeof r.reg); 510 * or 511 * copyin(uap->addr, &r.reg32, sizeof r.reg32); 512 * .. except this is done at runtime. 513 */ 514#define COPYIN(u, k, s) wrap32 ? \ 515 copyin(u, k ## 32, s ## 32) : \ 516 copyin(u, k, s) 517#define COPYOUT(k, u, s) wrap32 ? \ 518 copyout(k ## 32, u, s ## 32) : \ 519 copyout(k, u, s) 520#else 521#define COPYIN(u, k, s) copyin(u, k, s) 522#define COPYOUT(k, u, s) copyout(k, u, s) 523#endif 524int 525sys_ptrace(struct thread *td, struct ptrace_args *uap) 526{ 527 /* 528 * XXX this obfuscation is to reduce stack usage, but the register 529 * structs may be too large to put on the stack anyway. 530 */ 531 union { 532 struct ptrace_io_desc piod; 533 struct ptrace_lwpinfo pl; 534 struct ptrace_vm_entry pve; 535 struct dbreg dbreg; 536 struct fpreg fpreg; 537 struct reg reg; 538#ifdef COMPAT_FREEBSD32 539 struct dbreg32 dbreg32; 540 struct fpreg32 fpreg32; 541 struct reg32 reg32; 542 struct ptrace_io_desc32 piod32; 543 struct ptrace_lwpinfo32 pl32; 544 struct ptrace_vm_entry32 pve32; 545#endif 546 } r; 547 void *addr; 548 int error = 0; 549#ifdef COMPAT_FREEBSD32 550 int wrap32 = 0; 551 552 if (SV_CURPROC_FLAG(SV_ILP32)) 553 wrap32 = 1; 554#endif 555 AUDIT_ARG_PID(uap->pid); 556 AUDIT_ARG_CMD(uap->req); 557 AUDIT_ARG_VALUE(uap->data); 558 addr = &r; 559 switch (uap->req) { 560 case PT_GETREGS: 561 case PT_GETFPREGS: 562 case PT_GETDBREGS: 563 case PT_LWPINFO: 564 break; 565 case PT_SETREGS: 566 error = COPYIN(uap->addr, &r.reg, sizeof r.reg); 567 break; 568 case PT_SETFPREGS: 569 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); 570 break; 571 case PT_SETDBREGS: 572 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); 573 break; 574 case PT_IO: 575 error = COPYIN(uap->addr, &r.piod, sizeof r.piod); 576 break; 577 case PT_VM_ENTRY: 578 error = COPYIN(uap->addr, &r.pve, sizeof r.pve); 579 break; 580 default: 581 addr = uap->addr; 582 break; 583 } 584 if (error) 585 return (error); 586 587 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 588 if (error) 589 return (error); 590 591 switch (uap->req) { 592 case PT_VM_ENTRY: 593 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve); 594 break; 595 case PT_IO: 596 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); 597 break; 598 case PT_GETREGS: 599 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); 600 break; 601 case PT_GETFPREGS: 602 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); 603 break; 604 case PT_GETDBREGS: 605 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); 606 break; 607 case PT_LWPINFO: 608 error = copyout(&r.pl, uap->addr, uap->data); 609 break; 610 } 611 612 return (error); 613} 614#undef COPYIN 615#undef COPYOUT 616 617#ifdef COMPAT_FREEBSD32 618/* 619 * PROC_READ(regs, td2, addr); 620 * becomes either: 621 * proc_read_regs(td2, addr); 622 * or 623 * proc_read_regs32(td2, addr); 624 * .. except this is done at runtime. There is an additional 625 * complication in that PROC_WRITE disallows 32 bit consumers 626 * from writing to 64 bit address space targets. 627 */ 628#define PROC_READ(w, t, a) wrap32 ? \ 629 proc_read_ ## w ## 32(t, a) : \ 630 proc_read_ ## w (t, a) 631#define PROC_WRITE(w, t, a) wrap32 ? \ 632 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 633 proc_write_ ## w (t, a) 634#else 635#define PROC_READ(w, t, a) proc_read_ ## w (t, a) 636#define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 637#endif 638 639int 640kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 641{ 642 struct iovec iov; 643 struct uio uio; 644 struct proc *curp, *p, *pp; 645 struct thread *td2 = NULL, *td3; 646 struct ptrace_io_desc *piod = NULL; 647 struct ptrace_lwpinfo *pl; 648 int error, write, tmp, num; 649 int proctree_locked = 0; 650 lwpid_t tid = 0, *buf; 651#ifdef COMPAT_FREEBSD32 652 int wrap32 = 0, safe = 0; 653 struct ptrace_io_desc32 *piod32 = NULL; 654 struct ptrace_lwpinfo32 *pl32 = NULL; 655 struct ptrace_lwpinfo plr; 656#endif 657 658 curp = td->td_proc; 659 660 /* Lock proctree before locking the process. */ 661 switch (req) { 662 case PT_TRACE_ME: 663 case PT_ATTACH: 664 case PT_STEP: 665 case PT_CONTINUE: 666 case PT_TO_SCE: 667 case PT_TO_SCX: 668 case PT_SYSCALL: 669 case PT_FOLLOW_FORK: 670 case PT_DETACH: 671 sx_xlock(&proctree_lock); 672 proctree_locked = 1; 673 break; 674 default: 675 break; 676 } 677 678 write = 0; 679 if (req == PT_TRACE_ME) { 680 p = td->td_proc; 681 PROC_LOCK(p); 682 } else { 683 if (pid <= PID_MAX) { 684 if ((p = pfind(pid)) == NULL) { 685 if (proctree_locked) 686 sx_xunlock(&proctree_lock); 687 return (ESRCH); 688 } 689 } else { 690 td2 = tdfind(pid, -1); 691 if (td2 == NULL) { 692 if (proctree_locked) 693 sx_xunlock(&proctree_lock); 694 return (ESRCH); 695 } 696 p = td2->td_proc; 697 tid = pid; 698 pid = p->p_pid; 699 } 700 } 701 AUDIT_ARG_PROCESS(p); 702 703 if ((p->p_flag & P_WEXIT) != 0) { 704 error = ESRCH; 705 goto fail; 706 } 707 if ((error = p_cansee(td, p)) != 0) 708 goto fail; 709 710 if ((error = p_candebug(td, p)) != 0) 711 goto fail; 712 713 /* 714 * System processes can't be debugged. 715 */ 716 if ((p->p_flag & P_SYSTEM) != 0) { 717 error = EINVAL; 718 goto fail; 719 } 720 721 if (tid == 0) { 722 if ((p->p_flag & P_STOPPED_TRACE) != 0) { 723 KASSERT(p->p_xthread != NULL, ("NULL p_xthread")); 724 td2 = p->p_xthread; 725 } else { 726 td2 = FIRST_THREAD_IN_PROC(p); 727 } 728 tid = td2->td_tid; 729 } 730 731#ifdef COMPAT_FREEBSD32 732 /* 733 * Test if we're a 32 bit client and what the target is. 734 * Set the wrap controls accordingly. 735 */ 736 if (SV_CURPROC_FLAG(SV_ILP32)) { 737 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32)) 738 safe = 1; 739 wrap32 = 1; 740 } 741#endif 742 /* 743 * Permissions check 744 */ 745 switch (req) { 746 case PT_TRACE_ME: 747 /* 748 * Always legal, when there is a parent process which 749 * could trace us. Otherwise, reject. 750 */ 751 if ((p->p_flag & P_TRACED) != 0) { 752 error = EBUSY; 753 goto fail; 754 } 755 if (p->p_pptr == initproc) { 756 error = EPERM; 757 goto fail; 758 } 759 break; 760 761 case PT_ATTACH: 762 /* Self */ 763 if (p == td->td_proc) { 764 error = EINVAL; 765 goto fail; 766 } 767 768 /* Already traced */ 769 if (p->p_flag & P_TRACED) { 770 error = EBUSY; 771 goto fail; 772 } 773 774 /* Can't trace an ancestor if you're being traced. */ 775 if (curp->p_flag & P_TRACED) { 776 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 777 if (pp == p) { 778 error = EINVAL; 779 goto fail; 780 } 781 } 782 } 783 784 785 /* OK */ 786 break; 787 788 case PT_CLEARSTEP: 789 /* Allow thread to clear single step for itself */ 790 if (td->td_tid == tid) 791 break; 792 793 /* FALLTHROUGH */ 794 default: 795 /* not being traced... */ 796 if ((p->p_flag & P_TRACED) == 0) { 797 error = EPERM; 798 goto fail; 799 } 800 801 /* not being traced by YOU */ 802 if (p->p_pptr != td->td_proc) { 803 error = EBUSY; 804 goto fail; 805 } 806 807 /* not currently stopped */ 808 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 || 809 p->p_suspcount != p->p_numthreads || 810 (p->p_flag & P_WAITED) == 0) { 811 error = EBUSY; 812 goto fail; 813 } 814 815 if ((p->p_flag & P_STOPPED_TRACE) == 0) { 816 static int count = 0; 817 if (count++ == 0) 818 printf("P_STOPPED_TRACE not set.\n"); 819 } 820 821 /* OK */ 822 break; 823 } 824 825 /* Keep this process around until we finish this request. */ 826 _PHOLD(p); 827 828#ifdef FIX_SSTEP 829 /* 830 * Single step fixup ala procfs 831 */ 832 FIX_SSTEP(td2); 833#endif 834 835 /* 836 * Actually do the requests 837 */ 838 839 td->td_retval[0] = 0; 840 841 switch (req) { 842 case PT_TRACE_ME: 843 /* set my trace flag and "owner" so it can read/write me */ 844 p->p_flag |= P_TRACED; 845 if (p->p_flag & P_PPWAIT) 846 p->p_flag |= P_PPTRACE; 847 p->p_oppid = p->p_pptr->p_pid; 848 CTR1(KTR_PTRACE, "PT_TRACE_ME: pid %d", p->p_pid); 849 break; 850 851 case PT_ATTACH: 852 /* security check done above */ 853 /* 854 * It would be nice if the tracing relationship was separate 855 * from the parent relationship but that would require 856 * another set of links in the proc struct or for "wait" 857 * to scan the entire proc table. To make life easier, 858 * we just re-parent the process we're trying to trace. 859 * The old parent is remembered so we can put things back 860 * on a "detach". 861 */ 862 p->p_flag |= P_TRACED; 863 p->p_oppid = p->p_pptr->p_pid; 864 if (p->p_pptr != td->td_proc) { 865 proc_reparent(p, td->td_proc); 866 } 867 data = SIGSTOP; 868 CTR2(KTR_PTRACE, "PT_ATTACH: pid %d, oppid %d", p->p_pid, 869 p->p_oppid); 870 goto sendsig; /* in PT_CONTINUE below */ 871 872 case PT_CLEARSTEP: 873 CTR2(KTR_PTRACE, "PT_CLEARSTEP: tid %d (pid %d)", td2->td_tid, 874 p->p_pid); 875 error = ptrace_clear_single_step(td2); 876 break; 877 878 case PT_SETSTEP: 879 CTR2(KTR_PTRACE, "PT_SETSTEP: tid %d (pid %d)", td2->td_tid, 880 p->p_pid); 881 error = ptrace_single_step(td2); 882 break; 883 884 case PT_SUSPEND: 885 CTR2(KTR_PTRACE, "PT_SUSPEND: tid %d (pid %d)", td2->td_tid, 886 p->p_pid); 887 td2->td_dbgflags |= TDB_SUSPEND; 888 thread_lock(td2); 889 td2->td_flags |= TDF_NEEDSUSPCHK; 890 thread_unlock(td2); 891 break; 892 893 case PT_RESUME: 894 CTR2(KTR_PTRACE, "PT_RESUME: tid %d (pid %d)", td2->td_tid, 895 p->p_pid); 896 td2->td_dbgflags &= ~TDB_SUSPEND; 897 break; 898 899 case PT_FOLLOW_FORK: 900 CTR3(KTR_PTRACE, "PT_FOLLOW_FORK: pid %d %s -> %s", p->p_pid, 901 p->p_flag & P_FOLLOWFORK ? "enabled" : "disabled", 902 data ? "enabled" : "disabled"); 903 if (data) 904 p->p_flag |= P_FOLLOWFORK; 905 else 906 p->p_flag &= ~P_FOLLOWFORK; 907 break; 908 909 case PT_STEP: 910 case PT_CONTINUE: 911 case PT_TO_SCE: 912 case PT_TO_SCX: 913 case PT_SYSCALL: 914 case PT_DETACH: 915 /* Zero means do not send any signal */ 916 if (data < 0 || data > _SIG_MAXSIG) { 917 error = EINVAL; 918 break; 919 } 920 921 switch (req) { 922 case PT_STEP: 923 CTR2(KTR_PTRACE, "PT_STEP: tid %d (pid %d)", 924 td2->td_tid, p->p_pid); 925 error = ptrace_single_step(td2); 926 if (error) 927 goto out; 928 break; 929 case PT_CONTINUE: 930 case PT_TO_SCE: 931 case PT_TO_SCX: 932 case PT_SYSCALL: 933 if (addr != (void *)1) { 934 error = ptrace_set_pc(td2, 935 (u_long)(uintfptr_t)addr); 936 if (error) 937 goto out; 938 } 939 switch (req) { 940 case PT_TO_SCE: 941 p->p_stops |= S_PT_SCE; 942 CTR4(KTR_PTRACE, 943 "PT_TO_SCE: pid %d, stops = %#x, PC = %#lx, sig = %d", 944 p->p_pid, p->p_stops, 945 (u_long)(uintfptr_t)addr, data); 946 break; 947 case PT_TO_SCX: 948 p->p_stops |= S_PT_SCX; 949 CTR4(KTR_PTRACE, 950 "PT_TO_SCX: pid %d, stops = %#x, PC = %#lx, sig = %d", 951 p->p_pid, p->p_stops, 952 (u_long)(uintfptr_t)addr, data); 953 break; 954 case PT_SYSCALL: 955 p->p_stops |= S_PT_SCE | S_PT_SCX; 956 CTR4(KTR_PTRACE, 957 "PT_SYSCALL: pid %d, stops = %#x, PC = %#lx, sig = %d", 958 p->p_pid, p->p_stops, 959 (u_long)(uintfptr_t)addr, data); 960 break; 961 case PT_CONTINUE: 962 CTR3(KTR_PTRACE, 963 "PT_CONTINUE: pid %d, PC = %#lx, sig = %d", 964 p->p_pid, (u_long)(uintfptr_t)addr, data); 965 break; 966 } 967 break; 968 case PT_DETACH: 969 /* 970 * Reset the process parent. 971 * 972 * NB: This clears P_TRACED before reparenting 973 * a detached process back to its original 974 * parent. Otherwise the debugee will be set 975 * as an orphan of the debugger. 976 */ 977 p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK); 978 if (p->p_oppid != p->p_pptr->p_pid) { 979 PROC_LOCK(p->p_pptr); 980 sigqueue_take(p->p_ksi); 981 PROC_UNLOCK(p->p_pptr); 982 983 pp = proc_realparent(p); 984 proc_reparent(p, pp); 985 if (pp == initproc) 986 p->p_sigparent = SIGCHLD; 987 CTR3(KTR_PTRACE, 988 "PT_DETACH: pid %d reparented to pid %d, sig %d", 989 p->p_pid, pp->p_pid, data); 990 } else 991 CTR2(KTR_PTRACE, "PT_DETACH: pid %d, sig %d", 992 p->p_pid, data); 993 p->p_oppid = 0; 994 p->p_stops = 0; 995 996 /* should we send SIGCHLD? */ 997 /* childproc_continued(p); */ 998 break; 999 } 1000 1001 sendsig: 1002 if (proctree_locked) { 1003 sx_xunlock(&proctree_lock); 1004 proctree_locked = 0; 1005 } 1006 p->p_xstat = data; 1007 p->p_xthread = NULL; 1008 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) { 1009 /* deliver or queue signal */ 1010 td2->td_dbgflags &= ~TDB_XSIG; 1011 td2->td_xsig = data; 1012 1013 if (req == PT_DETACH) { 1014 FOREACH_THREAD_IN_PROC(p, td3) 1015 td3->td_dbgflags &= ~TDB_SUSPEND; 1016 } 1017 /* 1018 * unsuspend all threads, to not let a thread run, 1019 * you should use PT_SUSPEND to suspend it before 1020 * continuing process. 1021 */ 1022 PROC_SLOCK(p); 1023 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED); 1024 thread_unsuspend(p); 1025 PROC_SUNLOCK(p); 1026 if (req == PT_ATTACH) 1027 kern_psignal(p, data); 1028 } else { 1029 if (data) 1030 kern_psignal(p, data); 1031 } 1032 break; 1033 1034 case PT_WRITE_I: 1035 case PT_WRITE_D: 1036 td2->td_dbgflags |= TDB_USERWR; 1037 write = 1; 1038 /* FALLTHROUGH */ 1039 case PT_READ_I: 1040 case PT_READ_D: 1041 PROC_UNLOCK(p); 1042 tmp = 0; 1043 /* write = 0 set above */ 1044 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 1045 iov.iov_len = sizeof(int); 1046 uio.uio_iov = &iov; 1047 uio.uio_iovcnt = 1; 1048 uio.uio_offset = (off_t)(uintptr_t)addr; 1049 uio.uio_resid = sizeof(int); 1050 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */ 1051 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 1052 uio.uio_td = td; 1053 error = proc_rwmem(p, &uio); 1054 if (uio.uio_resid != 0) { 1055 /* 1056 * XXX proc_rwmem() doesn't currently return ENOSPC, 1057 * so I think write() can bogusly return 0. 1058 * XXX what happens for short writes? We don't want 1059 * to write partial data. 1060 * XXX proc_rwmem() returns EPERM for other invalid 1061 * addresses. Convert this to EINVAL. Does this 1062 * clobber returns of EPERM for other reasons? 1063 */ 1064 if (error == 0 || error == ENOSPC || error == EPERM) 1065 error = EINVAL; /* EOF */ 1066 } 1067 if (!write) 1068 td->td_retval[0] = tmp; 1069 if (error == 0) { 1070 if (write) 1071 CTR3(KTR_PTRACE, "PT_WRITE: pid %d: %p <= %#x", 1072 p->p_pid, addr, data); 1073 else 1074 CTR3(KTR_PTRACE, "PT_READ: pid %d: %p >= %#x", 1075 p->p_pid, addr, tmp); 1076 } 1077 PROC_LOCK(p); 1078 break; 1079 1080 case PT_IO: 1081#ifdef COMPAT_FREEBSD32 1082 if (wrap32) { 1083 piod32 = addr; 1084 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; 1085 iov.iov_len = piod32->piod_len; 1086 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; 1087 uio.uio_resid = piod32->piod_len; 1088 } else 1089#endif 1090 { 1091 piod = addr; 1092 iov.iov_base = piod->piod_addr; 1093 iov.iov_len = piod->piod_len; 1094 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 1095 uio.uio_resid = piod->piod_len; 1096 } 1097 uio.uio_iov = &iov; 1098 uio.uio_iovcnt = 1; 1099 uio.uio_segflg = UIO_USERSPACE; 1100 uio.uio_td = td; 1101#ifdef COMPAT_FREEBSD32 1102 tmp = wrap32 ? piod32->piod_op : piod->piod_op; 1103#else 1104 tmp = piod->piod_op; 1105#endif 1106 switch (tmp) { 1107 case PIOD_READ_D: 1108 case PIOD_READ_I: 1109 CTR3(KTR_PTRACE, "PT_IO: pid %d: READ (%p, %#x)", 1110 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid); 1111 uio.uio_rw = UIO_READ; 1112 break; 1113 case PIOD_WRITE_D: 1114 case PIOD_WRITE_I: 1115 CTR3(KTR_PTRACE, "PT_IO: pid %d: WRITE (%p, %#x)", 1116 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid); 1117 td2->td_dbgflags |= TDB_USERWR; 1118 uio.uio_rw = UIO_WRITE; 1119 break; 1120 default: 1121 error = EINVAL; 1122 goto out; 1123 } 1124 PROC_UNLOCK(p); 1125 error = proc_rwmem(p, &uio); 1126#ifdef COMPAT_FREEBSD32 1127 if (wrap32) 1128 piod32->piod_len -= uio.uio_resid; 1129 else 1130#endif 1131 piod->piod_len -= uio.uio_resid; 1132 PROC_LOCK(p); 1133 break; 1134 1135 case PT_KILL: 1136 CTR1(KTR_PTRACE, "PT_KILL: pid %d", p->p_pid); 1137 data = SIGKILL; 1138 goto sendsig; /* in PT_CONTINUE above */ 1139 1140 case PT_SETREGS: 1141 CTR2(KTR_PTRACE, "PT_SETREGS: tid %d (pid %d)", td2->td_tid, 1142 p->p_pid); 1143 td2->td_dbgflags |= TDB_USERWR; 1144 error = PROC_WRITE(regs, td2, addr); 1145 break; 1146 1147 case PT_GETREGS: 1148 CTR2(KTR_PTRACE, "PT_GETREGS: tid %d (pid %d)", td2->td_tid, 1149 p->p_pid); 1150 error = PROC_READ(regs, td2, addr); 1151 break; 1152 1153 case PT_SETFPREGS: 1154 CTR2(KTR_PTRACE, "PT_SETFPREGS: tid %d (pid %d)", td2->td_tid, 1155 p->p_pid); 1156 td2->td_dbgflags |= TDB_USERWR; 1157 error = PROC_WRITE(fpregs, td2, addr); 1158 break; 1159 1160 case PT_GETFPREGS: 1161 CTR2(KTR_PTRACE, "PT_GETFPREGS: tid %d (pid %d)", td2->td_tid, 1162 p->p_pid); 1163 error = PROC_READ(fpregs, td2, addr); 1164 break; 1165 1166 case PT_SETDBREGS: 1167 CTR2(KTR_PTRACE, "PT_SETDBREGS: tid %d (pid %d)", td2->td_tid, 1168 p->p_pid); 1169 td2->td_dbgflags |= TDB_USERWR; 1170 error = PROC_WRITE(dbregs, td2, addr); 1171 break; 1172 1173 case PT_GETDBREGS: 1174 CTR2(KTR_PTRACE, "PT_GETDBREGS: tid %d (pid %d)", td2->td_tid, 1175 p->p_pid); 1176 error = PROC_READ(dbregs, td2, addr); 1177 break; 1178 1179 case PT_LWPINFO: 1180 if (data <= 0 || 1181#ifdef COMPAT_FREEBSD32 1182 (!wrap32 && data > sizeof(*pl)) || 1183 (wrap32 && data > sizeof(*pl32))) { 1184#else 1185 data > sizeof(*pl)) { 1186#endif 1187 error = EINVAL; 1188 break; 1189 } 1190#ifdef COMPAT_FREEBSD32 1191 if (wrap32) { 1192 pl = &plr; 1193 pl32 = addr; 1194 } else 1195#endif 1196 pl = addr; 1197 bzero(pl, sizeof(*pl)); 1198 pl->pl_lwpid = td2->td_tid; 1199 pl->pl_event = PL_EVENT_NONE; 1200 pl->pl_flags = 0; 1201 if (td2->td_dbgflags & TDB_XSIG) { 1202 pl->pl_event = PL_EVENT_SIGNAL; 1203 if (td2->td_dbgksi.ksi_signo != 0 && 1204#ifdef COMPAT_FREEBSD32 1205 ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo, 1206 pl_siginfo) + sizeof(pl->pl_siginfo)) || 1207 (wrap32 && data >= offsetof(struct ptrace_lwpinfo32, 1208 pl_siginfo) + sizeof(struct siginfo32))) 1209#else 1210 data >= offsetof(struct ptrace_lwpinfo, pl_siginfo) 1211 + sizeof(pl->pl_siginfo) 1212#endif 1213 ){ 1214 pl->pl_flags |= PL_FLAG_SI; 1215 pl->pl_siginfo = td2->td_dbgksi.ksi_info; 1216 } 1217 } 1218 if (td2->td_dbgflags & TDB_SCE) 1219 pl->pl_flags |= PL_FLAG_SCE; 1220 else if (td2->td_dbgflags & TDB_SCX) 1221 pl->pl_flags |= PL_FLAG_SCX; 1222 if (td2->td_dbgflags & TDB_EXEC) 1223 pl->pl_flags |= PL_FLAG_EXEC; 1224 if (td2->td_dbgflags & TDB_FORK) { 1225 pl->pl_flags |= PL_FLAG_FORKED; 1226 pl->pl_child_pid = td2->td_dbg_forked; 1227 } 1228 if (td2->td_dbgflags & TDB_CHILD) 1229 pl->pl_flags |= PL_FLAG_CHILD; 1230 pl->pl_sigmask = td2->td_sigmask; 1231 pl->pl_siglist = td2->td_siglist; 1232 strcpy(pl->pl_tdname, td2->td_name); 1233 if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) != 0) { 1234 pl->pl_syscall_code = td2->td_dbg_sc_code; 1235 pl->pl_syscall_narg = td2->td_dbg_sc_narg; 1236 } else { 1237 pl->pl_syscall_code = 0; 1238 pl->pl_syscall_narg = 0; 1239 } 1240#ifdef COMPAT_FREEBSD32 1241 if (wrap32) 1242 ptrace_lwpinfo_to32(pl, pl32); 1243#endif 1244 CTR6(KTR_PTRACE, 1245 "PT_LWPINFO: tid %d (pid %d) event %d flags %#x child pid %d syscall %d", 1246 td2->td_tid, p->p_pid, pl->pl_event, pl->pl_flags, 1247 pl->pl_child_pid, pl->pl_syscall_code); 1248 break; 1249 1250 case PT_GETNUMLWPS: 1251 CTR2(KTR_PTRACE, "PT_GETNUMLWPS: pid %d: %d threads", p->p_pid, 1252 p->p_numthreads); 1253 td->td_retval[0] = p->p_numthreads; 1254 break; 1255 1256 case PT_GETLWPLIST: 1257 CTR3(KTR_PTRACE, "PT_GETLWPLIST: pid %d: data %d, actual %d", 1258 p->p_pid, data, p->p_numthreads); 1259 if (data <= 0) { 1260 error = EINVAL; 1261 break; 1262 } 1263 num = imin(p->p_numthreads, data); 1264 PROC_UNLOCK(p); 1265 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 1266 tmp = 0; 1267 PROC_LOCK(p); 1268 FOREACH_THREAD_IN_PROC(p, td2) { 1269 if (tmp >= num) 1270 break; 1271 buf[tmp++] = td2->td_tid; 1272 } 1273 PROC_UNLOCK(p); 1274 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 1275 free(buf, M_TEMP); 1276 if (!error) 1277 td->td_retval[0] = tmp; 1278 PROC_LOCK(p); 1279 break; 1280 1281 case PT_VM_TIMESTAMP: 1282 CTR2(KTR_PTRACE, "PT_VM_TIMESTAMP: pid %d: timestamp %d", 1283 p->p_pid, p->p_vmspace->vm_map.timestamp); 1284 td->td_retval[0] = p->p_vmspace->vm_map.timestamp; 1285 break; 1286 1287 case PT_VM_ENTRY: 1288 PROC_UNLOCK(p); 1289#ifdef COMPAT_FREEBSD32 1290 if (wrap32) 1291 error = ptrace_vm_entry32(td, p, addr); 1292 else 1293#endif 1294 error = ptrace_vm_entry(td, p, addr); 1295 PROC_LOCK(p); 1296 break; 1297 1298 default: 1299#ifdef __HAVE_PTRACE_MACHDEP 1300 if (req >= PT_FIRSTMACH) { 1301 PROC_UNLOCK(p); 1302 error = cpu_ptrace(td2, req, addr, data); 1303 PROC_LOCK(p); 1304 } else 1305#endif 1306 /* Unknown request. */ 1307 error = EINVAL; 1308 break; 1309 } 1310 1311out: 1312 /* Drop our hold on this process now that the request has completed. */ 1313 _PRELE(p); 1314fail: 1315 PROC_UNLOCK(p); 1316 if (proctree_locked) 1317 sx_xunlock(&proctree_lock); 1318 return (error); 1319} 1320#undef PROC_READ 1321#undef PROC_WRITE 1322 1323/* 1324 * Stop a process because of a debugging event; 1325 * stay stopped until p->p_step is cleared 1326 * (cleared by PIOCCONT in procfs). 1327 */ 1328void 1329stopevent(struct proc *p, unsigned int event, unsigned int val) 1330{ 1331 1332 PROC_LOCK_ASSERT(p, MA_OWNED); 1333 p->p_step = 1; 1334 CTR3(KTR_PTRACE, "stopevent: pid %d event %u val %u", p->p_pid, event, 1335 val); 1336 do { 1337 p->p_xstat = val; 1338 p->p_xthread = NULL; 1339 p->p_stype = event; /* Which event caused the stop? */ 1340 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ 1341 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); 1342 } while (p->p_step); 1343} 1344