sys_machdep.c revision 1.1
1 /* $NetBSD: sys_machdep.c,v 1.1 2007/04/16 19:12:19 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2007 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Charles M. Hannum, and by Andrew Doran. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: sys_machdep.c,v 1.1 2007/04/16 19:12:19 ad Exp $"); 41 42 #include "opt_compat_netbsd.h" 43 #include "opt_mtrr.h" 44 #include "opt_perfctrs.h" 45 #include "opt_user_ldt.h" 46 #include "opt_vm86.h" 47 #include "opt_xen.h" 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/ioctl.h> 52 #include <sys/file.h> 53 #include <sys/time.h> 54 #include <sys/proc.h> 55 #include <sys/user.h> 56 #include <sys/uio.h> 57 #include <sys/kernel.h> 58 #include <sys/buf.h> 59 #include <sys/signal.h> 60 #include <sys/malloc.h> 61 #include <sys/kauth.h> 62 63 #include <sys/mount.h> 64 #include <sys/syscallargs.h> 65 66 #include <uvm/uvm_extern.h> 67 68 #include <machine/cpu.h> 69 #include <machine/cpufunc.h> 70 #include <machine/gdt.h> 71 #include <machine/psl.h> 72 #include <machine/reg.h> 73 #include <machine/sysarch.h> 74 #include <machine/mtrr.h> 75 76 #ifdef __x86_64__ 77 /* Need to be checked. */ 78 #undef USER_LDT 79 #undef PERFCTRS 80 #undef VM86 81 #undef IOPERM 82 #else 83 #define IOPERM 84 #endif 85 86 #ifdef VM86 87 #include <machine/vm86.h> 88 #endif 89 90 #ifdef PERFCTRS 91 #include <machine/pmc.h> 92 #endif 93 94 extern struct vm_map *kernel_map; 95 96 int x86_get_ioperm(struct lwp *, void *, register_t *); 97 int x86_set_ioperm(struct lwp *, void *, register_t *); 98 int x86_get_mtrr(struct lwp *, void *, register_t *); 99 int x86_set_mtrr(struct lwp *, void *, register_t *); 100 101 #ifdef LDT_DEBUG 102 static void x86_print_ldt(int, const struct segment_descriptor *); 103 104 static void 105 x86_print_ldt(int i, const struct segment_descriptor *d) 106 { 107 printf("[%d] lolimit=0x%x, lobase=0x%x, type=%u, dpl=%u, p=%u, " 108 "hilimit=0x%x, xx=%x, def32=%u, gran=%u, hibase=0x%x\n", 109 i, d->sd_lolimit, d->sd_lobase, d->sd_type, d->sd_dpl, d->sd_p, 110 d->sd_hilimit, d->sd_xx, d->sd_def32, d->sd_gran, d->sd_hibase); 111 } 112 #endif 113 114 int 115 x86_get_ldt(struct lwp *l, void *args, register_t *retval) 116 { 117 #ifdef USER_LDT 118 int error; 119 struct proc *p = l->l_proc; 120 pmap_t pmap = p->p_vmspace->vm_map.pmap; 121 int nldt, num; 122 union descriptor *lp, *cp; 123 struct x86_get_ldt_args ua; 124 125 error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_LDT_GET, 126 NULL, NULL, NULL, NULL); 127 if (error) 128 return (error); 129 130 if ((error = copyin(args, &ua, sizeof(ua))) != 0) 131 return (error); 132 133 #ifdef LDT_DEBUG 134 printf("x86_get_ldt: start=%d num=%d descs=%p\n", ua.start, 135 ua.num, ua.desc); 136 #endif 137 138 if (ua.start < 0 || ua.num < 0 || ua.start > 8192 || ua.num > 8192 || 139 ua.start + ua.num > 8192) 140 return (EINVAL); 141 142 cp = malloc(ua.num * sizeof(union descriptor), M_TEMP, M_WAITOK); 143 if (cp == NULL) 144 return ENOMEM; 145 146 simple_lock(&pmap->pm_lock); 147 148 if (pmap->pm_flags & PMF_USER_LDT) { 149 nldt = pmap->pm_ldt_len; 150 lp = pmap->pm_ldt; 151 } else { 152 nldt = NLDT; 153 lp = ldt; 154 } 155 156 if (ua.start > nldt) { 157 simple_unlock(&pmap->pm_lock); 158 free(cp, M_TEMP); 159 return (EINVAL); 160 } 161 162 lp += ua.start; 163 num = min(ua.num, nldt - ua.start); 164 #ifdef LDT_DEBUG 165 { 166 int i; 167 for (i = 0; i < num; i++) 168 x86_print_ldt(i, &lp[i].sd); 169 } 170 #endif 171 172 memcpy(cp, lp, num * sizeof(union descriptor)); 173 simple_unlock(&pmap->pm_lock); 174 175 error = copyout(cp, ua.desc, num * sizeof(union descriptor)); 176 if (error == 0) 177 *retval = num; 178 179 free(cp, M_TEMP); 180 return (error); 181 #else 182 return EINVAL; 183 #endif 184 } 185 186 int 187 x86_set_ldt(struct lwp *l, void *args, register_t *retval) 188 { 189 #ifdef USER_LDT 190 int error, i, n, sel, free_sel; 191 struct proc *p = l->l_proc; 192 struct pcb *pcb = &l->l_addr->u_pcb; 193 pmap_t pmap = p->p_vmspace->vm_map.pmap; 194 struct x86_set_ldt_args ua; 195 union descriptor *descv; 196 size_t old_len, new_len, ldt_len, free_len; 197 union descriptor *old_ldt, *new_ldt, *free_ldt; 198 199 error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_LDT_SET, 200 NULL, NULL, NULL, NULL); 201 if (error) 202 return (error); 203 204 if ((error = copyin(args, &ua, sizeof(ua))) != 0) 205 return (error); 206 207 if (ua.start < 0 || ua.num < 0 || ua.start > 8192 || ua.num > 8192 || 208 ua.start + ua.num > 8192) 209 return (EINVAL); 210 211 descv = malloc(sizeof (*descv) * ua.num, M_TEMP, M_NOWAIT); 212 if (descv == NULL) 213 return (ENOMEM); 214 215 if ((error = copyin(ua.desc, descv, sizeof (*descv) * ua.num)) != 0) 216 goto out; 217 218 /* Check descriptors for access violations. */ 219 for (i = 0; i < ua.num; i++) { 220 union descriptor *desc = &descv[i]; 221 222 switch (desc->sd.sd_type) { 223 case SDT_SYSNULL: 224 desc->sd.sd_p = 0; 225 break; 226 case SDT_SYS286CGT: 227 case SDT_SYS386CGT: 228 /* 229 * Only allow call gates targeting a segment 230 * in the LDT or a user segment in the fixed 231 * part of the gdt. Segments in the LDT are 232 * constrained (below) to be user segments. 233 */ 234 if (desc->gd.gd_p != 0 && 235 !ISLDT(desc->gd.gd_selector) && 236 ((IDXSEL(desc->gd.gd_selector) >= NGDT) || 237 (gdt[IDXSEL(desc->gd.gd_selector)].sd.sd_dpl != 238 SEL_UPL))) { 239 error = EACCES; 240 goto out; 241 } 242 break; 243 case SDT_MEMEC: 244 case SDT_MEMEAC: 245 case SDT_MEMERC: 246 case SDT_MEMERAC: 247 /* Must be "present" if executable and conforming. */ 248 if (desc->sd.sd_p == 0) { 249 error = EACCES; 250 goto out; 251 } 252 break; 253 case SDT_MEMRO: 254 case SDT_MEMROA: 255 case SDT_MEMRW: 256 case SDT_MEMRWA: 257 case SDT_MEMROD: 258 case SDT_MEMRODA: 259 case SDT_MEMRWD: 260 case SDT_MEMRWDA: 261 case SDT_MEME: 262 case SDT_MEMEA: 263 case SDT_MEMER: 264 case SDT_MEMERA: 265 break; 266 default: 267 /* 268 * Make sure that unknown descriptor types are 269 * not marked present. 270 */ 271 if (desc->sd.sd_p != 0) { 272 error = EACCES; 273 goto out; 274 } 275 break; 276 } 277 278 if (desc->sd.sd_p != 0) { 279 /* Only user (ring-3) descriptors may be present. */ 280 if (desc->sd.sd_dpl != SEL_UPL) { 281 error = EACCES; 282 goto out; 283 } 284 } 285 } 286 287 /* allocate user ldt */ 288 free_sel = -1; 289 new_ldt = NULL; 290 new_len = 0; 291 free_ldt = NULL; 292 free_len = 0; 293 simple_lock(&pmap->pm_lock); 294 if (pmap->pm_ldt == 0 || (ua.start + ua.num) > pmap->pm_ldt_len) { 295 if (pmap->pm_flags & PMF_USER_LDT) 296 ldt_len = pmap->pm_ldt_len; 297 else 298 ldt_len = 512; 299 while ((ua.start + ua.num) > ldt_len) 300 ldt_len *= 2; 301 new_len = ldt_len * sizeof(union descriptor); 302 303 simple_unlock(&pmap->pm_lock); 304 new_ldt = (union descriptor *)uvm_km_alloc(kernel_map, 305 new_len, 0, UVM_KMF_WIRED); 306 memset(new_ldt, 0, new_len); 307 sel = ldt_alloc(new_ldt, new_len); 308 simple_lock(&pmap->pm_lock); 309 310 if (pmap->pm_ldt != NULL && ldt_len <= pmap->pm_ldt_len) { 311 /* 312 * Another thread (re)allocated the LDT to 313 * sufficient size while we were blocked in 314 * uvm_km_alloc. Oh well. The new entries 315 * will quite probably not be right, but 316 * hey.. not our problem if user applications 317 * have race conditions like that. 318 */ 319 goto copy; 320 } 321 322 old_ldt = pmap->pm_ldt; 323 free_ldt = old_ldt; 324 free_len = pmap->pm_ldt_len * sizeof(union descriptor); 325 326 if (old_ldt != NULL) { 327 old_len = pmap->pm_ldt_len * sizeof(union descriptor); 328 } else { 329 old_len = NLDT * sizeof(union descriptor); 330 old_ldt = ldt; 331 } 332 333 memcpy(new_ldt, old_ldt, old_len); 334 memset((char *)new_ldt + old_len, 0, new_len - old_len); 335 336 pmap->pm_ldt = new_ldt; 337 pmap->pm_ldt_len = ldt_len; 338 339 if (pmap->pm_flags & PMF_USER_LDT) 340 free_sel = pmap->pm_ldt_sel; 341 else { 342 pmap->pm_flags |= PMF_USER_LDT; 343 free_sel = -1; 344 } 345 pmap->pm_ldt_sel = sel; 346 pcb->pcb_ldt_sel = pmap->pm_ldt_sel; 347 if (pcb == curpcb) 348 lldt(pcb->pcb_ldt_sel); 349 new_ldt = NULL; 350 } 351 copy: 352 /* Now actually replace the descriptors. */ 353 for (i = 0, n = ua.start; i < ua.num; i++, n++) 354 pmap->pm_ldt[n] = descv[i]; 355 356 simple_unlock(&pmap->pm_lock); 357 *retval = ua.start; 358 359 if (new_ldt != NULL) 360 uvm_km_free(kernel_map, (vaddr_t)new_ldt, new_len, 361 UVM_KMF_WIRED); 362 if (free_sel != -1) 363 ldt_free(free_sel); 364 if (free_ldt != NULL) 365 uvm_km_free(kernel_map, (vaddr_t)free_ldt, free_len, 366 UVM_KMF_WIRED); 367 out: 368 free(descv, M_TEMP); 369 return (error); 370 #else 371 return EINVAL; 372 #endif 373 } 374 375 int 376 x86_iopl(struct lwp *l, void *args, register_t *retval) 377 { 378 int error; 379 struct x86_iopl_args ua; 380 #ifdef XEN 381 struct pcb *pcb = &l->l_addr->u_pcb; 382 #else 383 struct trapframe *tf = l->l_md.md_regs; 384 #endif 385 386 error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_IOPL, 387 NULL, NULL, NULL, NULL); 388 if (error) 389 return (error); 390 391 if ((error = copyin(args, &ua, sizeof(ua))) != 0) 392 return error; 393 394 #ifdef XEN 395 { 396 pcb->pcb_tss.tss_ioopt &= ~SEL_RPL; 397 if (ua.iopl) 398 pcb->pcb_tss.tss_ioopt |= SEL_UPL; /* i/o pl */ 399 else 400 pcb->pcb_tss.tss_ioopt |= SEL_KPL; /* i/o pl */ 401 } 402 /* Force the change at ring 0. */ 403 #ifdef XEN3 404 { 405 struct physdev_op physop; 406 physop.cmd = PHYSDEVOP_SET_IOPL; 407 physop.u.set_iopl.iopl = pcb->pcb_tss.tss_ioopt & SEL_RPL; 408 HYPERVISOR_physdev_op(&physop); 409 } 410 #else /* XEN3 */ 411 { 412 dom0_op_t op; 413 op.cmd = DOM0_IOPL; 414 op.u.iopl.domain = DOMID_SELF; 415 op.u.iopl.iopl = pcb->pcb_tss.tss_ioopt & SEL_RPL; /* i/o pl */ 416 HYPERVISOR_dom0_op(&op); 417 } 418 #endif /* XEN3 */ 419 #elif defined(__x86_64__) 420 if (ua.iopl) 421 tf->tf_rflags |= PSL_IOPL; 422 else 423 tf->tf_rflags &= ~PSL_IOPL; 424 #else 425 if (ua.iopl) 426 tf->tf_eflags |= PSL_IOPL; 427 else 428 tf->tf_eflags &= ~PSL_IOPL; 429 #endif 430 431 return 0; 432 } 433 434 int 435 x86_get_ioperm(struct lwp *l, void *args, register_t *retval) 436 { 437 #ifdef IOPERM 438 int error; 439 struct pcb *pcb = &l->l_addr->u_pcb; 440 struct x86_get_ioperm_args ua; 441 442 error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_IOPERM_GET, 443 NULL, NULL, NULL, NULL); 444 if (error) 445 return (error); 446 447 if ((error = copyin(args, &ua, sizeof(ua))) != 0) 448 return (error); 449 450 return copyout(pcb->pcb_iomap, ua.iomap, sizeof(pcb->pcb_iomap)); 451 #else 452 return EINVAL; 453 #endif 454 } 455 456 int 457 x86_set_ioperm(struct lwp *l, void *args, register_t *retval) 458 { 459 #ifdef IOPERM 460 int error; 461 struct pcb *pcb = &l->l_addr->u_pcb; 462 struct x86_set_ioperm_args ua; 463 464 error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_IOPERM_SET, 465 NULL, NULL, NULL, NULL); 466 if (error) 467 return (error); 468 469 if ((error = copyin(args, &ua, sizeof(ua))) != 0) 470 return (error); 471 472 return copyin(ua.iomap, pcb->pcb_iomap, sizeof(pcb->pcb_iomap)); 473 #else 474 return EINVAL; 475 #endif 476 } 477 478 int 479 x86_get_mtrr(struct lwp *l, void *args, register_t *retval) 480 { 481 #ifdef MTRR 482 struct x86_get_mtrr_args ua; 483 int error, n; 484 485 if (mtrr_funcs == NULL) 486 return ENOSYS; 487 488 error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_MTRR_GET, 489 NULL, NULL, NULL, NULL); 490 if (error) 491 return (error); 492 493 error = copyin(args, &ua, sizeof ua); 494 if (error != 0) 495 return error; 496 497 error = copyin(ua.n, &n, sizeof n); 498 if (error != 0) 499 return error; 500 501 error = mtrr_get(ua.mtrrp, &n, l->l_proc, MTRR_GETSET_USER); 502 503 copyout(&n, ua.n, sizeof (int)); 504 505 return error; 506 #else 507 return EINVAL; 508 #endif 509 } 510 511 int 512 x86_set_mtrr(struct lwp *l, void *args, register_t *retval) 513 { 514 #ifdef MTRR 515 int error, n; 516 struct x86_set_mtrr_args ua; 517 518 if (mtrr_funcs == NULL) 519 return ENOSYS; 520 521 error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_MTRR_SET, 522 NULL, NULL, NULL, NULL); 523 if (error) 524 return (error); 525 526 error = copyin(args, &ua, sizeof ua); 527 if (error != 0) 528 return error; 529 530 error = copyin(ua.n, &n, sizeof n); 531 if (error != 0) 532 return error; 533 534 error = mtrr_set(ua.mtrrp, &n, l->l_proc, MTRR_GETSET_USER); 535 if (n != 0) 536 mtrr_commit(); 537 538 copyout(&n, ua.n, sizeof n); 539 540 return error; 541 #else 542 return EINVAL; 543 #endif 544 } 545 546 int 547 sys_sysarch(struct lwp *l, void *v, register_t *retval) 548 { 549 struct sys_sysarch_args /* { 550 syscallarg(int) op; 551 syscallarg(void *) parms; 552 } */ *uap = v; 553 int error = 0; 554 555 switch(SCARG(uap, op)) { 556 case X86_IOPL: 557 error = x86_iopl(l, SCARG(uap, parms), retval); 558 break; 559 560 case X86_GET_LDT: 561 error = x86_get_ldt(l, SCARG(uap, parms), retval); 562 break; 563 564 case X86_SET_LDT: 565 error = x86_set_ldt(l, SCARG(uap, parms), retval); 566 break; 567 568 case X86_GET_IOPERM: 569 error = x86_get_ioperm(l, SCARG(uap, parms), retval); 570 break; 571 572 case X86_SET_IOPERM: 573 error = x86_set_ioperm(l, SCARG(uap, parms), retval); 574 break; 575 576 case X86_GET_MTRR: 577 error = x86_get_mtrr(l, SCARG(uap, parms), retval); 578 break; 579 case X86_SET_MTRR: 580 error = x86_set_mtrr(l, SCARG(uap, parms), retval); 581 break; 582 583 #ifdef VM86 584 case X86_VM86: 585 error = x86_vm86(l, SCARG(uap, parms), retval); 586 break; 587 #ifdef COMPAT_16 588 case X86_OLD_VM86: 589 error = compat_16_x86_vm86(l, SCARG(uap, parms), retval); 590 break; 591 #endif 592 #endif 593 594 #ifdef PERFCTRS 595 case X86_PMC_INFO: 596 error = pmc_info(l, SCARG(uap, parms), retval); 597 break; 598 599 case X86_PMC_STARTSTOP: 600 error = pmc_startstop(l, SCARG(uap, parms), retval); 601 break; 602 603 case X86_PMC_READ: 604 error = pmc_read(l, SCARG(uap, parms), retval); 605 break; 606 #endif 607 608 default: 609 error = EINVAL; 610 break; 611 } 612 return (error); 613 } 614
Indexes created Thu Sep 25 08:09:54 GMT 2025