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_flag & 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_flag & 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_flag & 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_flag & 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_flag & 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_flag & 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_flag |= 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_flag |= 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_flag &= ~(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 lp->lwp_flag |= LWP_BREAKTSLEEP; 527 proc_unstop(p); 528 } else if (data) { 529 ksignal(p, data); 530 } 531 crit_exit(); 532 lwkt_reltoken(&p->p_token); 533 PRELE(p); 534 lwkt_reltoken(&proc_token); 535 return 0; 536 537 case PT_WRITE_I: 538 case PT_WRITE_D: 539 write = 1; 540 /* fallthrough */ 541 case PT_READ_I: 542 case PT_READ_D: 543 /* 544 * NOTE! uio_offset represents the offset in the target 545 * process. The iov is in the current process (the guy 546 * making the ptrace call) so uio_td must be the current 547 * process (though for a SYSSPACE transfer it doesn't 548 * really matter). 549 */ 550 tmp = 0; 551 /* write = 0 set above */ 552 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 553 iov.iov_len = sizeof(int); 554 uio.uio_iov = &iov; 555 uio.uio_iovcnt = 1; 556 uio.uio_offset = (off_t)(uintptr_t)addr; 557 uio.uio_resid = sizeof(int); 558 uio.uio_segflg = UIO_SYSSPACE; 559 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 560 uio.uio_td = curthread; 561 error = procfs_domem(curp, lp, NULL, &uio); 562 if (uio.uio_resid != 0) { 563 /* 564 * XXX procfs_domem() doesn't currently return ENOSPC, 565 * so I think write() can bogusly return 0. 566 * XXX what happens for short writes? We don't want 567 * to write partial data. 568 * XXX procfs_domem() returns EPERM for other invalid 569 * addresses. Convert this to EINVAL. Does this 570 * clobber returns of EPERM for other reasons? 571 */ 572 if (error == 0 || error == ENOSPC || error == EPERM) 573 error = EINVAL; /* EOF */ 574 } 575 if (!write) 576 *res = tmp; 577 lwkt_reltoken(&p->p_token); 578 PRELE(p); 579 lwkt_reltoken(&proc_token); 580 return (error); 581 582 case PT_IO: 583 /* 584 * NOTE! uio_offset represents the offset in the target 585 * process. The iov is in the current process (the guy 586 * making the ptrace call) so uio_td must be the current 587 * process. 588 */ 589 piod = addr; 590 iov.iov_base = piod->piod_addr; 591 iov.iov_len = piod->piod_len; 592 uio.uio_iov = &iov; 593 uio.uio_iovcnt = 1; 594 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 595 uio.uio_resid = piod->piod_len; 596 uio.uio_segflg = UIO_USERSPACE; 597 uio.uio_td = curthread; 598 switch (piod->piod_op) { 599 case PIOD_READ_D: 600 case PIOD_READ_I: 601 uio.uio_rw = UIO_READ; 602 break; 603 case PIOD_WRITE_D: 604 case PIOD_WRITE_I: 605 uio.uio_rw = UIO_WRITE; 606 break; 607 default: 608 lwkt_reltoken(&p->p_token); 609 PRELE(p); 610 lwkt_reltoken(&proc_token); 611 return (EINVAL); 612 } 613 error = procfs_domem(curp, lp, NULL, &uio); 614 piod->piod_len -= uio.uio_resid; 615 lwkt_reltoken(&p->p_token); 616 PRELE(p); 617 lwkt_reltoken(&proc_token); 618 return (error); 619 620 case PT_KILL: 621 data = SIGKILL; 622 goto sendsig; /* in PT_CONTINUE above */ 623 624 #ifdef PT_SETREGS 625 case PT_SETREGS: 626 write = 1; 627 /* fallthrough */ 628 #endif /* PT_SETREGS */ 629 #ifdef PT_GETREGS 630 case PT_GETREGS: 631 /* write = 0 above */ 632 #endif /* PT_SETREGS */ 633 #if defined(PT_SETREGS) || defined(PT_GETREGS) 634 if (!procfs_validregs(lp)) { /* no P_SYSTEM procs please */ 635 lwkt_reltoken(&p->p_token); 636 PRELE(p); 637 lwkt_reltoken(&proc_token); 638 return EINVAL; 639 } else { 640 iov.iov_base = addr; 641 iov.iov_len = sizeof(struct reg); 642 uio.uio_iov = &iov; 643 uio.uio_iovcnt = 1; 644 uio.uio_offset = 0; 645 uio.uio_resid = sizeof(struct reg); 646 uio.uio_segflg = UIO_SYSSPACE; 647 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 648 uio.uio_td = curthread; 649 t = procfs_doregs(curp, lp, NULL, &uio); 650 lwkt_reltoken(&p->p_token); 651 PRELE(p); 652 lwkt_reltoken(&proc_token); 653 return t; 654 } 655 #endif /* defined(PT_SETREGS) || defined(PT_GETREGS) */ 656 657 #ifdef PT_SETFPREGS 658 case PT_SETFPREGS: 659 write = 1; 660 /* fallthrough */ 661 #endif /* PT_SETFPREGS */ 662 #ifdef PT_GETFPREGS 663 case PT_GETFPREGS: 664 /* write = 0 above */ 665 #endif /* PT_SETFPREGS */ 666 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS) 667 if (!procfs_validfpregs(lp)) { /* no P_SYSTEM procs please */ 668 lwkt_reltoken(&p->p_token); 669 PRELE(p); 670 lwkt_reltoken(&proc_token); 671 return EINVAL; 672 } else { 673 iov.iov_base = addr; 674 iov.iov_len = sizeof(struct fpreg); 675 uio.uio_iov = &iov; 676 uio.uio_iovcnt = 1; 677 uio.uio_offset = 0; 678 uio.uio_resid = sizeof(struct fpreg); 679 uio.uio_segflg = UIO_SYSSPACE; 680 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 681 uio.uio_td = curthread; 682 t = procfs_dofpregs(curp, lp, NULL, &uio); 683 lwkt_reltoken(&p->p_token); 684 PRELE(p); 685 lwkt_reltoken(&proc_token); 686 return t; 687 } 688 #endif /* defined(PT_SETFPREGS) || defined(PT_GETFPREGS) */ 689 690 #ifdef PT_SETDBREGS 691 case PT_SETDBREGS: 692 write = 1; 693 /* fallthrough */ 694 #endif /* PT_SETDBREGS */ 695 #ifdef PT_GETDBREGS 696 case PT_GETDBREGS: 697 /* write = 0 above */ 698 #endif /* PT_SETDBREGS */ 699 #if defined(PT_SETDBREGS) || defined(PT_GETDBREGS) 700 if (!procfs_validdbregs(lp)) { /* no P_SYSTEM procs please */ 701 lwkt_reltoken(&p->p_token); 702 PRELE(p); 703 lwkt_reltoken(&proc_token); 704 return EINVAL; 705 } else { 706 iov.iov_base = addr; 707 iov.iov_len = sizeof(struct dbreg); 708 uio.uio_iov = &iov; 709 uio.uio_iovcnt = 1; 710 uio.uio_offset = 0; 711 uio.uio_resid = sizeof(struct dbreg); 712 uio.uio_segflg = UIO_SYSSPACE; 713 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 714 uio.uio_td = curthread; 715 t = procfs_dodbregs(curp, lp, NULL, &uio); 716 lwkt_reltoken(&p->p_token); 717 PRELE(p); 718 lwkt_reltoken(&proc_token); 719 return t; 720 } 721 #endif /* defined(PT_SETDBREGS) || defined(PT_GETDBREGS) */ 722 723 default: 724 break; 725 } 726 727 lwkt_reltoken(&p->p_token); 728 PRELE(p); 729 lwkt_reltoken(&proc_token); 730 731 return 0; 732 } 733 734 int 735 trace_req(struct proc *p) 736 { 737 return 1; 738 } 739 740 /* 741 * stopevent() 742 * 743 * Stop a process because of a procfs event. Stay stopped until p->p_step 744 * is cleared (cleared by PIOCCONT in procfs). 745 * 746 * MPSAFE 747 */ 748 void 749 stopevent(struct proc *p, unsigned int event, unsigned int val) 750 { 751 /* 752 * Set event info. Recheck p_stops in case we are 753 * racing a close() on procfs. 754 */ 755 spin_lock(&p->p_spin); 756 if ((p->p_stops & event) == 0) { 757 spin_unlock(&p->p_spin); 758 return; 759 } 760 p->p_xstat = val; 761 p->p_stype = event; 762 p->p_step = 1; 763 tsleep_interlock(&p->p_step, 0); 764 spin_unlock(&p->p_spin); 765 766 /* 767 * Wakeup any PIOCWAITing procs and wait for p_step to 768 * be cleared. 769 */ 770 for (;;) { 771 wakeup(&p->p_stype); 772 tsleep(&p->p_step, PINTERLOCKED, "stopevent", 0); 773 spin_lock(&p->p_spin); 774 if (p->p_step == 0) { 775 spin_unlock(&p->p_spin); 776 break; 777 } 778 tsleep_interlock(&p->p_step, 0); 779 spin_unlock(&p->p_spin); 780 } 781 } 782 783