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 * $FreeBSD: src/sys/kern/sys_process.c,v 1.51.2.6 2003/01/08 03:06:45 kan Exp $ 32 * $DragonFly: src/sys/kern/sys_process.c,v 1.30 2007/02/19 01:14:23 corecode Exp $ 33 */ 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/sysproto.h> 38 #include <sys/proc.h> 39 #include <sys/priv.h> 40 #include <sys/vnode.h> 41 #include <sys/ptrace.h> 42 #include <sys/reg.h> 43 #include <sys/lock.h> 44 45 #include <vm/vm.h> 46 #include <vm/pmap.h> 47 #include <vm/vm_map.h> 48 #include <vm/vm_page.h> 49 50 #include <sys/user.h> 51 #include <vfs/procfs/procfs.h> 52 53 #include <sys/thread2.h> 54 #include <sys/spinlock2.h> 55 56 /* use the equivalent procfs code */ 57 #if 0 58 static int 59 pread (struct proc *procp, unsigned int addr, unsigned int *retval) { 60 int rv; 61 vm_map_t map, tmap; 62 vm_object_t object; 63 vm_offset_t kva = 0; 64 int page_offset; /* offset into page */ 65 vm_offset_t pageno; /* page number */ 66 vm_map_entry_t out_entry; 67 vm_prot_t out_prot; 68 boolean_t wired; 69 vm_pindex_t pindex; 70 71 /* Map page into kernel space */ 72 73 map = &procp->p_vmspace->vm_map; 74 75 page_offset = addr - trunc_page(addr); 76 pageno = trunc_page(addr); 77 78 tmap = map; 79 rv = vm_map_lookup(&tmap, pageno, VM_PROT_READ, &out_entry, 80 &object, &pindex, &out_prot, &wired); 81 82 if (rv != KERN_SUCCESS) 83 return EINVAL; 84 85 vm_map_lookup_done (tmap, out_entry, 0); 86 87 /* Find space in kernel_map for the page we're interested in */ 88 rv = vm_map_find (&kernel_map, object, IDX_TO_OFF(pindex), 89 &kva, 90 PAGE_SIZE, PAGE_SIZE, 91 0, VM_MAPTYPE_NORMAL, 92 VM_PROT_ALL, VM_PROT_ALL, 93 0); 94 95 if (!rv) { 96 vm_object_reference XXX (object); 97 98 rv = vm_map_wire (&kernel_map, kva, kva + PAGE_SIZE, 0); 99 if (!rv) { 100 *retval = 0; 101 bcopy ((caddr_t)kva + page_offset, 102 retval, sizeof *retval); 103 } 104 vm_map_remove (&kernel_map, kva, kva + PAGE_SIZE); 105 } 106 107 return rv; 108 } 109 110 static int 111 pwrite (struct proc *procp, unsigned int addr, unsigned int datum) { 112 int rv; 113 vm_map_t map, tmap; 114 vm_object_t object; 115 vm_offset_t kva = 0; 116 int page_offset; /* offset into page */ 117 vm_offset_t pageno; /* page number */ 118 vm_map_entry_t out_entry; 119 vm_prot_t out_prot; 120 boolean_t wired; 121 vm_pindex_t pindex; 122 boolean_t fix_prot = 0; 123 124 /* Map page into kernel space */ 125 126 map = &procp->p_vmspace->vm_map; 127 128 page_offset = addr - trunc_page(addr); 129 pageno = trunc_page(addr); 130 131 /* 132 * Check the permissions for the area we're interested in. 133 */ 134 135 if (vm_map_check_protection (map, pageno, pageno + PAGE_SIZE, 136 VM_PROT_WRITE, FALSE) == FALSE) { 137 /* 138 * If the page was not writable, we make it so. 139 * XXX It is possible a page may *not* be read/executable, 140 * if a process changes that! 141 */ 142 fix_prot = 1; 143 /* The page isn't writable, so let's try making it so... */ 144 if ((rv = vm_map_protect (map, pageno, pageno + PAGE_SIZE, 145 VM_PROT_ALL, 0)) != KERN_SUCCESS) 146 return EFAULT; /* I guess... */ 147 } 148 149 /* 150 * Now we need to get the page. out_entry, out_prot, wired, and 151 * single_use aren't used. One would think the vm code would be 152 * a *bit* nicer... We use tmap because vm_map_lookup() can 153 * change the map argument. 154 */ 155 156 tmap = map; 157 rv = vm_map_lookup(&tmap, pageno, VM_PROT_WRITE, &out_entry, 158 &object, &pindex, &out_prot, &wired); 159 if (rv != KERN_SUCCESS) 160 return EINVAL; 161 162 /* 163 * Okay, we've got the page. Let's release tmap. 164 */ 165 vm_map_lookup_done (tmap, out_entry, 0); 166 167 /* 168 * Fault the page in... 169 */ 170 rv = vm_fault(map, pageno, VM_PROT_WRITE|VM_PROT_READ, FALSE); 171 if (rv != KERN_SUCCESS) 172 return EFAULT; 173 174 /* Find space in kernel_map for the page we're interested in */ 175 rv = vm_map_find (&kernel_map, object, IDX_TO_OFF(pindex), 176 &kva, 177 PAGE_SIZE, PAGE_SIZE, 178 0, VM_MAPTYPE_NORMAL, 179 VM_PROT_ALL, VM_PROT_ALL, 180 0); 181 if (!rv) { 182 vm_object_reference XXX (object); 183 184 rv = vm_map_wire (&kernel_map, kva, kva + PAGE_SIZE, 0); 185 if (!rv) { 186 bcopy (&datum, (caddr_t)kva + page_offset, sizeof datum); 187 } 188 vm_map_remove (&kernel_map, kva, kva + PAGE_SIZE); 189 } 190 191 if (fix_prot) 192 vm_map_protect (map, pageno, pageno + PAGE_SIZE, 193 VM_PROT_READ|VM_PROT_EXECUTE, 0); 194 return rv; 195 } 196 #endif 197 198 /* 199 * Process debugging system call. 200 * 201 * MPALMOSTSAFE 202 */ 203 int 204 sys_ptrace(struct ptrace_args *uap) 205 { 206 struct proc *p = curproc; 207 208 /* 209 * XXX this obfuscation is to reduce stack usage, but the register 210 * structs may be too large to put on the stack anyway. 211 */ 212 union { 213 struct ptrace_io_desc piod; 214 struct dbreg dbreg; 215 struct fpreg fpreg; 216 struct reg reg; 217 } r; 218 void *addr; 219 int error = 0; 220 221 addr = &r; 222 switch (uap->req) { 223 case PT_GETREGS: 224 case PT_GETFPREGS: 225 #ifdef PT_GETDBREGS 226 case PT_GETDBREGS: 227 #endif 228 break; 229 case PT_SETREGS: 230 error = copyin(uap->addr, &r.reg, sizeof r.reg); 231 break; 232 case PT_SETFPREGS: 233 error = copyin(uap->addr, &r.fpreg, sizeof r.fpreg); 234 break; 235 #ifdef PT_SETDBREGS 236 case PT_SETDBREGS: 237 error = copyin(uap->addr, &r.dbreg, sizeof r.dbreg); 238 break; 239 #endif 240 case PT_IO: 241 error = copyin(uap->addr, &r.piod, sizeof r.piod); 242 break; 243 default: 244 addr = uap->addr; 245 } 246 if (error) 247 return (error); 248 249 error = kern_ptrace(p, uap->req, uap->pid, addr, uap->data, 250 &uap->sysmsg_result); 251 if (error) 252 return (error); 253 254 switch (uap->req) { 255 case PT_IO: 256 (void)copyout(&r.piod, uap->addr, sizeof r.piod); 257 break; 258 case PT_GETREGS: 259 error = copyout(&r.reg, uap->addr, sizeof r.reg); 260 break; 261 case PT_GETFPREGS: 262 error = copyout(&r.fpreg, uap->addr, sizeof r.fpreg); 263 break; 264 #ifdef PT_GETDBREGS 265 case PT_GETDBREGS: 266 error = copyout(&r.dbreg, uap->addr, sizeof r.dbreg); 267 break; 268 #endif 269 } 270 271 return (error); 272 } 273 274 int 275 kern_ptrace(struct proc *curp, int req, pid_t pid, void *addr, 276 int data, int *res) 277 { 278 struct proc *p, *pp; 279 struct lwp *lp; 280 struct iovec iov; 281 struct uio uio; 282 struct ptrace_io_desc *piod; 283 int error = 0; 284 int write, tmp; 285 int t; 286 287 lwkt_gettoken(&proc_token); 288 289 write = 0; 290 if (req == PT_TRACE_ME) { 291 p = curp; 292 PHOLD(p); 293 } else { 294 if ((p = pfind(pid)) == NULL) { 295 lwkt_reltoken(&proc_token); 296 return ESRCH; 297 } 298 } 299 if (!PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 300 PRELE(p); 301 lwkt_reltoken(&proc_token); 302 return (ESRCH); 303 } 304 305 lwkt_gettoken(&p->p_token); 306 /* Can't trace a process that's currently exec'ing. */ 307 if ((p->p_flags & P_INEXEC) != 0) { 308 lwkt_reltoken(&p->p_token); 309 PRELE(p); 310 lwkt_reltoken(&proc_token); 311 return EAGAIN; 312 } 313 314 /* 315 * Permissions check 316 */ 317 switch (req) { 318 case PT_TRACE_ME: 319 /* Always legal. */ 320 break; 321 322 case PT_ATTACH: 323 /* Self */ 324 if (p->p_pid == curp->p_pid) { 325 lwkt_reltoken(&p->p_token); 326 PRELE(p); 327 lwkt_reltoken(&proc_token); 328 return EINVAL; 329 } 330 331 /* Already traced */ 332 if (p->p_flags & P_TRACED) { 333 lwkt_reltoken(&p->p_token); 334 PRELE(p); 335 lwkt_reltoken(&proc_token); 336 return EBUSY; 337 } 338 339 if (curp->p_flags & P_TRACED) 340 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) 341 if (pp == p) { 342 lwkt_reltoken(&p->p_token); 343 PRELE(p); 344 lwkt_reltoken(&proc_token); 345 return (EINVAL); 346 } 347 348 /* not owned by you, has done setuid (unless you're root) */ 349 if ((p->p_ucred->cr_ruid != curp->p_ucred->cr_ruid) || 350 (p->p_flags & P_SUGID)) { 351 if ((error = priv_check_cred(curp->p_ucred, PRIV_ROOT, 0)) != 0) { 352 lwkt_reltoken(&p->p_token); 353 PRELE(p); 354 lwkt_reltoken(&proc_token); 355 return error; 356 } 357 } 358 359 /* can't trace init when securelevel > 0 */ 360 if (securelevel > 0 && p->p_pid == 1) { 361 lwkt_reltoken(&p->p_token); 362 PRELE(p); 363 lwkt_reltoken(&proc_token); 364 return EPERM; 365 } 366 367 /* OK */ 368 break; 369 370 case PT_READ_I: 371 case PT_READ_D: 372 case PT_WRITE_I: 373 case PT_WRITE_D: 374 case PT_IO: 375 case PT_CONTINUE: 376 case PT_KILL: 377 case PT_STEP: 378 case PT_DETACH: 379 #ifdef PT_GETREGS 380 case PT_GETREGS: 381 #endif 382 #ifdef PT_SETREGS 383 case PT_SETREGS: 384 #endif 385 #ifdef PT_GETFPREGS 386 case PT_GETFPREGS: 387 #endif 388 #ifdef PT_SETFPREGS 389 case PT_SETFPREGS: 390 #endif 391 #ifdef PT_GETDBREGS 392 case PT_GETDBREGS: 393 #endif 394 #ifdef PT_SETDBREGS 395 case PT_SETDBREGS: 396 #endif 397 /* not being traced... */ 398 if ((p->p_flags & P_TRACED) == 0) { 399 lwkt_reltoken(&p->p_token); 400 PRELE(p); 401 lwkt_reltoken(&proc_token); 402 return EPERM; 403 } 404 405 /* not being traced by YOU */ 406 if (p->p_pptr != curp) { 407 lwkt_reltoken(&p->p_token); 408 PRELE(p); 409 lwkt_reltoken(&proc_token); 410 return EBUSY; 411 } 412 413 /* not currently stopped */ 414 if (p->p_stat != SSTOP || 415 (p->p_flags & P_WAITED) == 0) { 416 lwkt_reltoken(&p->p_token); 417 PRELE(p); 418 lwkt_reltoken(&proc_token); 419 return EBUSY; 420 } 421 422 /* OK */ 423 break; 424 425 default: 426 lwkt_reltoken(&p->p_token); 427 PRELE(p); 428 lwkt_reltoken(&proc_token); 429 return EINVAL; 430 } 431 432 /* XXX lwp */ 433 lp = FIRST_LWP_IN_PROC(p); 434 #ifdef FIX_SSTEP 435 /* 436 * Single step fixup ala procfs 437 */ 438 FIX_SSTEP(lp); 439 #endif 440 441 /* 442 * Actually do the requests 443 */ 444 445 *res = 0; 446 447 switch (req) { 448 case PT_TRACE_ME: 449 /* set my trace flag and "owner" so it can read/write me */ 450 p->p_flags |= P_TRACED; 451 p->p_oppid = p->p_pptr->p_pid; 452 lwkt_reltoken(&p->p_token); 453 PRELE(p); 454 lwkt_reltoken(&proc_token); 455 return 0; 456 457 case PT_ATTACH: 458 /* security check done above */ 459 p->p_flags |= P_TRACED; 460 p->p_oppid = p->p_pptr->p_pid; 461 if (p->p_pptr != curp) 462 proc_reparent(p, curp); 463 data = SIGSTOP; 464 goto sendsig; /* in PT_CONTINUE below */ 465 466 case PT_STEP: 467 case PT_CONTINUE: 468 case PT_DETACH: 469 /* Zero means do not send any signal */ 470 if (data < 0 || data > _SIG_MAXSIG) { 471 lwkt_reltoken(&p->p_token); 472 PRELE(p); 473 lwkt_reltoken(&proc_token); 474 return EINVAL; 475 } 476 477 LWPHOLD(lp); 478 479 if (req == PT_STEP) { 480 if ((error = ptrace_single_step (lp))) { 481 LWPRELE(lp); 482 lwkt_reltoken(&p->p_token); 483 PRELE(p); 484 lwkt_reltoken(&proc_token); 485 return error; 486 } 487 } 488 489 if (addr != (void *)1) { 490 if ((error = ptrace_set_pc (lp, 491 (u_long)(uintfptr_t)addr))) { 492 LWPRELE(lp); 493 lwkt_reltoken(&p->p_token); 494 PRELE(p); 495 lwkt_reltoken(&proc_token); 496 return error; 497 } 498 } 499 LWPRELE(lp); 500 501 if (req == PT_DETACH) { 502 /* reset process parent */ 503 if (p->p_oppid != p->p_pptr->p_pid) { 504 struct proc *pp; 505 506 pp = pfind(p->p_oppid); 507 proc_reparent(p, pp ? pp : initproc); 508 if (pp != NULL) 509 PRELE(pp); 510 } 511 512 p->p_flags &= ~(P_TRACED | P_WAITED); 513 p->p_oppid = 0; 514 515 /* should we send SIGCHLD? */ 516 } 517 518 sendsig: 519 /* 520 * Deliver or queue signal. If the process is stopped 521 * force it to be SACTIVE again. 522 */ 523 crit_enter(); 524 if (p->p_stat == SSTOP) { 525 p->p_xstat = data; 526 proc_unstop(p); 527 } else if (data) { 528 ksignal(p, data); 529 } 530 crit_exit(); 531 lwkt_reltoken(&p->p_token); 532 PRELE(p); 533 lwkt_reltoken(&proc_token); 534 return 0; 535 536 case PT_WRITE_I: 537 case PT_WRITE_D: 538 write = 1; 539 /* fallthrough */ 540 case PT_READ_I: 541 case PT_READ_D: 542 /* 543 * NOTE! uio_offset represents the offset in the target 544 * process. The iov is in the current process (the guy 545 * making the ptrace call) so uio_td must be the current 546 * process (though for a SYSSPACE transfer it doesn't 547 * really matter). 548 */ 549 tmp = 0; 550 /* write = 0 set above */ 551 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 552 iov.iov_len = sizeof(int); 553 uio.uio_iov = &iov; 554 uio.uio_iovcnt = 1; 555 uio.uio_offset = (off_t)(uintptr_t)addr; 556 uio.uio_resid = sizeof(int); 557 uio.uio_segflg = UIO_SYSSPACE; 558 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 559 uio.uio_td = curthread; 560 error = procfs_domem(curp, lp, NULL, &uio); 561 if (uio.uio_resid != 0) { 562 /* 563 * XXX procfs_domem() doesn't currently return ENOSPC, 564 * so I think write() can bogusly return 0. 565 * XXX what happens for short writes? We don't want 566 * to write partial data. 567 * XXX procfs_domem() returns EPERM for other invalid 568 * addresses. Convert this to EINVAL. Does this 569 * clobber returns of EPERM for other reasons? 570 */ 571 if (error == 0 || error == ENOSPC || error == EPERM) 572 error = EINVAL; /* EOF */ 573 } 574 if (!write) 575 *res = tmp; 576 lwkt_reltoken(&p->p_token); 577 PRELE(p); 578 lwkt_reltoken(&proc_token); 579 return (error); 580 581 case PT_IO: 582 /* 583 * NOTE! uio_offset represents the offset in the target 584 * process. The iov is in the current process (the guy 585 * making the ptrace call) so uio_td must be the current 586 * process. 587 */ 588 piod = addr; 589 iov.iov_base = piod->piod_addr; 590 iov.iov_len = piod->piod_len; 591 uio.uio_iov = &iov; 592 uio.uio_iovcnt = 1; 593 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 594 uio.uio_resid = piod->piod_len; 595 uio.uio_segflg = UIO_USERSPACE; 596 uio.uio_td = curthread; 597 switch (piod->piod_op) { 598 case PIOD_READ_D: 599 case PIOD_READ_I: 600 uio.uio_rw = UIO_READ; 601 break; 602 case PIOD_WRITE_D: 603 case PIOD_WRITE_I: 604 uio.uio_rw = UIO_WRITE; 605 break; 606 default: 607 lwkt_reltoken(&p->p_token); 608 PRELE(p); 609 lwkt_reltoken(&proc_token); 610 return (EINVAL); 611 } 612 error = procfs_domem(curp, lp, NULL, &uio); 613 piod->piod_len -= uio.uio_resid; 614 lwkt_reltoken(&p->p_token); 615 PRELE(p); 616 lwkt_reltoken(&proc_token); 617 return (error); 618 619 case PT_KILL: 620 data = SIGKILL; 621 goto sendsig; /* in PT_CONTINUE above */ 622 623 #ifdef PT_SETREGS 624 case PT_SETREGS: 625 write = 1; 626 /* fallthrough */ 627 #endif /* PT_SETREGS */ 628 #ifdef PT_GETREGS 629 case PT_GETREGS: 630 /* write = 0 above */ 631 #endif /* PT_SETREGS */ 632 #if defined(PT_SETREGS) || defined(PT_GETREGS) 633 if (!procfs_validregs(lp)) { /* no P_SYSTEM procs please */ 634 lwkt_reltoken(&p->p_token); 635 PRELE(p); 636 lwkt_reltoken(&proc_token); 637 return EINVAL; 638 } else { 639 iov.iov_base = addr; 640 iov.iov_len = sizeof(struct reg); 641 uio.uio_iov = &iov; 642 uio.uio_iovcnt = 1; 643 uio.uio_offset = 0; 644 uio.uio_resid = sizeof(struct reg); 645 uio.uio_segflg = UIO_SYSSPACE; 646 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 647 uio.uio_td = curthread; 648 t = procfs_doregs(curp, lp, NULL, &uio); 649 lwkt_reltoken(&p->p_token); 650 PRELE(p); 651 lwkt_reltoken(&proc_token); 652 return t; 653 } 654 #endif /* defined(PT_SETREGS) || defined(PT_GETREGS) */ 655 656 #ifdef PT_SETFPREGS 657 case PT_SETFPREGS: 658 write = 1; 659 /* fallthrough */ 660 #endif /* PT_SETFPREGS */ 661 #ifdef PT_GETFPREGS 662 case PT_GETFPREGS: 663 /* write = 0 above */ 664 #endif /* PT_SETFPREGS */ 665 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS) 666 if (!procfs_validfpregs(lp)) { /* no P_SYSTEM procs please */ 667 lwkt_reltoken(&p->p_token); 668 PRELE(p); 669 lwkt_reltoken(&proc_token); 670 return EINVAL; 671 } else { 672 iov.iov_base = addr; 673 iov.iov_len = sizeof(struct fpreg); 674 uio.uio_iov = &iov; 675 uio.uio_iovcnt = 1; 676 uio.uio_offset = 0; 677 uio.uio_resid = sizeof(struct fpreg); 678 uio.uio_segflg = UIO_SYSSPACE; 679 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 680 uio.uio_td = curthread; 681 t = procfs_dofpregs(curp, lp, NULL, &uio); 682 lwkt_reltoken(&p->p_token); 683 PRELE(p); 684 lwkt_reltoken(&proc_token); 685 return t; 686 } 687 #endif /* defined(PT_SETFPREGS) || defined(PT_GETFPREGS) */ 688 689 #ifdef PT_SETDBREGS 690 case PT_SETDBREGS: 691 write = 1; 692 /* fallthrough */ 693 #endif /* PT_SETDBREGS */ 694 #ifdef PT_GETDBREGS 695 case PT_GETDBREGS: 696 /* write = 0 above */ 697 #endif /* PT_SETDBREGS */ 698 #if defined(PT_SETDBREGS) || defined(PT_GETDBREGS) 699 if (!procfs_validdbregs(lp)) { /* no P_SYSTEM procs please */ 700 lwkt_reltoken(&p->p_token); 701 PRELE(p); 702 lwkt_reltoken(&proc_token); 703 return EINVAL; 704 } else { 705 iov.iov_base = addr; 706 iov.iov_len = sizeof(struct dbreg); 707 uio.uio_iov = &iov; 708 uio.uio_iovcnt = 1; 709 uio.uio_offset = 0; 710 uio.uio_resid = sizeof(struct dbreg); 711 uio.uio_segflg = UIO_SYSSPACE; 712 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 713 uio.uio_td = curthread; 714 t = procfs_dodbregs(curp, lp, NULL, &uio); 715 lwkt_reltoken(&p->p_token); 716 PRELE(p); 717 lwkt_reltoken(&proc_token); 718 return t; 719 } 720 #endif /* defined(PT_SETDBREGS) || defined(PT_GETDBREGS) */ 721 722 default: 723 break; 724 } 725 726 lwkt_reltoken(&p->p_token); 727 PRELE(p); 728 lwkt_reltoken(&proc_token); 729 730 return 0; 731 } 732 733 int 734 trace_req(struct proc *p) 735 { 736 return 1; 737 } 738 739 /* 740 * stopevent() 741 * 742 * Stop a process because of a procfs event. Stay stopped until p->p_step 743 * is cleared (cleared by PIOCCONT in procfs). 744 * 745 * MPSAFE 746 */ 747 void 748 stopevent(struct proc *p, unsigned int event, unsigned int val) 749 { 750 /* 751 * Set event info. Recheck p_stops in case we are 752 * racing a close() on procfs. 753 */ 754 spin_lock(&p->p_spin); 755 if ((p->p_stops & event) == 0) { 756 spin_unlock(&p->p_spin); 757 return; 758 } 759 p->p_xstat = val; 760 p->p_stype = event; 761 p->p_step = 1; 762 tsleep_interlock(&p->p_step, 0); 763 spin_unlock(&p->p_spin); 764 765 /* 766 * Wakeup any PIOCWAITing procs and wait for p_step to 767 * be cleared. 768 */ 769 for (;;) { 770 wakeup(&p->p_stype); 771 tsleep(&p->p_step, PINTERLOCKED, "stopevent", 0); 772 spin_lock(&p->p_spin); 773 if (p->p_step == 0) { 774 spin_unlock(&p->p_spin); 775 break; 776 } 777 tsleep_interlock(&p->p_step, 0); 778 spin_unlock(&p->p_spin); 779 } 780 } 781 782