| 1 | /*- |
| 2 | * Copyright (c) 1990 The Regents of the University of California. |
| 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 the University of |
| 16 | * California, Berkeley and its contributors. |
| 17 | * 4. Neither the name of the University nor the names of its contributors |
| 18 | * may be used to endorse or promote products derived from this software |
| 19 | * without specific prior written permission. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 31 | * SUCH DAMAGE. |
| 32 | * |
| 33 | * from: @(#)sys_machdep.c 5.5 (Berkeley) 1/19/91 |
| 34 | * $FreeBSD: src/sys/i386/i386/sys_machdep.c,v 1.47.2.3 2002/10/07 17:20:00 jhb Exp $ |
| 35 | * $DragonFly: src/sys/i386/i386/Attic/sys_machdep.c,v 1.10 2003/07/30 00:19:13 dillon Exp $ |
| 36 | * |
| 37 | */ |
| 38 | |
| 39 | #include "opt_user_ldt.h" |
| 40 | |
| 41 | #include <sys/param.h> |
| 42 | #include <sys/systm.h> |
| 43 | #include <sys/sysproto.h> |
| 44 | #include <sys/malloc.h> |
| 45 | #include <sys/thread.h> |
| 46 | #include <sys/proc.h> |
| 47 | |
| 48 | #include <vm/vm.h> |
| 49 | #include <sys/lock.h> |
| 50 | #include <vm/pmap.h> |
| 51 | #include <vm/vm_map.h> |
| 52 | #include <vm/vm_extern.h> |
| 53 | |
| 54 | #include <sys/user.h> |
| 55 | |
| 56 | #include <machine/cpu.h> |
| 57 | #include <machine/ipl.h> |
| 58 | #include <machine/pcb_ext.h> /* pcb.h included by sys/user.h */ |
| 59 | #include <machine/sysarch.h> |
| 60 | #ifdef SMP |
| 61 | #include <machine/smp.h> |
| 62 | #endif |
| 63 | #include <machine/globaldata.h> /* mdcpu */ |
| 64 | |
| 65 | #include <vm/vm_kern.h> /* for kernel_map */ |
| 66 | |
| 67 | #define MAX_LD 8192 |
| 68 | #define LD_PER_PAGE 512 |
| 69 | #define NEW_MAX_LD(num) ((num + LD_PER_PAGE) & ~(LD_PER_PAGE-1)) |
| 70 | #define SIZE_FROM_LARGEST_LD(num) (NEW_MAX_LD(num) << 3) |
| 71 | |
| 72 | |
| 73 | |
| 74 | #ifdef USER_LDT |
| 75 | static int i386_get_ldt __P((struct proc *, char *, int *)); |
| 76 | static int i386_set_ldt __P((struct proc *, char *, int *)); |
| 77 | #endif |
| 78 | static int i386_get_ioperm __P((struct proc *, char *)); |
| 79 | static int i386_set_ioperm __P((struct proc *, char *)); |
| 80 | int i386_extend_pcb __P((struct proc *)); |
| 81 | |
| 82 | /* |
| 83 | * sysarch_args(int op, char *params) |
| 84 | */ |
| 85 | |
| 86 | int |
| 87 | sysarch(struct sysarch_args *uap) |
| 88 | { |
| 89 | struct proc *p = curproc; |
| 90 | int error = 0; |
| 91 | |
| 92 | switch(uap->op) { |
| 93 | #ifdef USER_LDT |
| 94 | case I386_GET_LDT: |
| 95 | error = i386_get_ldt(p, uap->parms, &uap->sysmsg_result); |
| 96 | break; |
| 97 | |
| 98 | case I386_SET_LDT: |
| 99 | error = i386_set_ldt(p, uap->parms, &uap->sysmsg_result); |
| 100 | break; |
| 101 | #endif |
| 102 | case I386_GET_IOPERM: |
| 103 | error = i386_get_ioperm(p, uap->parms); |
| 104 | break; |
| 105 | case I386_SET_IOPERM: |
| 106 | error = i386_set_ioperm(p, uap->parms); |
| 107 | break; |
| 108 | case I386_VM86: |
| 109 | error = vm86_sysarch(p, uap->parms); |
| 110 | break; |
| 111 | default: |
| 112 | error = EOPNOTSUPP; |
| 113 | break; |
| 114 | } |
| 115 | return (error); |
| 116 | } |
| 117 | |
| 118 | int |
| 119 | i386_extend_pcb(struct proc *p) |
| 120 | { |
| 121 | int i, offset; |
| 122 | u_long *addr; |
| 123 | struct pcb_ext *ext; |
| 124 | struct soft_segment_descriptor ssd = { |
| 125 | 0, /* segment base address (overwritten) */ |
| 126 | ctob(IOPAGES + 1) - 1, /* length */ |
| 127 | SDT_SYS386TSS, /* segment type */ |
| 128 | 0, /* priority level */ |
| 129 | 1, /* descriptor present */ |
| 130 | 0, 0, |
| 131 | 0, /* default 32 size */ |
| 132 | 0 /* granularity */ |
| 133 | }; |
| 134 | |
| 135 | ext = (struct pcb_ext *)kmem_alloc(kernel_map, ctob(IOPAGES+1)); |
| 136 | if (ext == 0) |
| 137 | return (ENOMEM); |
| 138 | p->p_thread->td_pcb->pcb_ext = ext; |
| 139 | bzero(ext, sizeof(struct pcb_ext)); |
| 140 | ext->ext_tss.tss_esp0 = (unsigned)((char *)p->p_thread->td_pcb - 16); |
| 141 | ext->ext_tss.tss_ss0 = GSEL(GDATA_SEL, SEL_KPL); |
| 142 | /* |
| 143 | * The last byte of the i/o map must be followed by an 0xff byte. |
| 144 | * We arbitrarily allocate 16 bytes here, to keep the starting |
| 145 | * address on a doubleword boundary. |
| 146 | */ |
| 147 | offset = PAGE_SIZE - 16; |
| 148 | ext->ext_tss.tss_ioopt = |
| 149 | (offset - ((unsigned)&ext->ext_tss - (unsigned)ext)) << 16; |
| 150 | ext->ext_iomap = (caddr_t)ext + offset; |
| 151 | ext->ext_vm86.vm86_intmap = (caddr_t)ext + offset - 32; |
| 152 | |
| 153 | addr = (u_long *)ext->ext_vm86.vm86_intmap; |
| 154 | for (i = 0; i < (ctob(IOPAGES) + 32 + 16) / sizeof(u_long); i++) |
| 155 | *addr++ = ~0; |
| 156 | |
| 157 | ssd.ssd_base = (unsigned)&ext->ext_tss; |
| 158 | ssd.ssd_limit -= ((unsigned)&ext->ext_tss - (unsigned)ext); |
| 159 | ssdtosd(&ssd, &ext->ext_tssd); |
| 160 | |
| 161 | /* switch to the new TSS after syscall completes */ |
| 162 | need_resched(); |
| 163 | |
| 164 | return 0; |
| 165 | } |
| 166 | |
| 167 | static int |
| 168 | i386_set_ioperm(struct proc *p, char *args) |
| 169 | { |
| 170 | int i, error; |
| 171 | struct i386_ioperm_args ua; |
| 172 | char *iomap; |
| 173 | |
| 174 | if ((error = copyin(args, &ua, sizeof(struct i386_ioperm_args))) != 0) |
| 175 | return (error); |
| 176 | |
| 177 | if ((error = suser_cred(p->p_ucred, 0)) != 0) |
| 178 | return (error); |
| 179 | if (securelevel > 0) |
| 180 | return (EPERM); |
| 181 | /* |
| 182 | * XXX |
| 183 | * While this is restricted to root, we should probably figure out |
| 184 | * whether any other driver is using this i/o address, as so not to |
| 185 | * cause confusion. This probably requires a global 'usage registry'. |
| 186 | */ |
| 187 | |
| 188 | if (p->p_thread->td_pcb->pcb_ext == 0) |
| 189 | if ((error = i386_extend_pcb(p)) != 0) |
| 190 | return (error); |
| 191 | iomap = (char *)p->p_thread->td_pcb->pcb_ext->ext_iomap; |
| 192 | |
| 193 | if (ua.start + ua.length > IOPAGES * PAGE_SIZE * NBBY) |
| 194 | return (EINVAL); |
| 195 | |
| 196 | for (i = ua.start; i < ua.start + ua.length; i++) { |
| 197 | if (ua.enable) |
| 198 | iomap[i >> 3] &= ~(1 << (i & 7)); |
| 199 | else |
| 200 | iomap[i >> 3] |= (1 << (i & 7)); |
| 201 | } |
| 202 | return (error); |
| 203 | } |
| 204 | |
| 205 | static int |
| 206 | i386_get_ioperm(struct proc *p, char *args) |
| 207 | { |
| 208 | int i, state, error; |
| 209 | struct i386_ioperm_args ua; |
| 210 | char *iomap; |
| 211 | |
| 212 | if ((error = copyin(args, &ua, sizeof(struct i386_ioperm_args))) != 0) |
| 213 | return (error); |
| 214 | if (ua.start >= IOPAGES * PAGE_SIZE * NBBY) |
| 215 | return (EINVAL); |
| 216 | |
| 217 | if (p->p_thread->td_pcb->pcb_ext == 0) { |
| 218 | ua.length = 0; |
| 219 | goto done; |
| 220 | } |
| 221 | |
| 222 | iomap = (char *)p->p_thread->td_pcb->pcb_ext->ext_iomap; |
| 223 | |
| 224 | i = ua.start; |
| 225 | state = (iomap[i >> 3] >> (i & 7)) & 1; |
| 226 | ua.enable = !state; |
| 227 | ua.length = 1; |
| 228 | |
| 229 | for (i = ua.start + 1; i < IOPAGES * PAGE_SIZE * NBBY; i++) { |
| 230 | if (state != ((iomap[i >> 3] >> (i & 7)) & 1)) |
| 231 | break; |
| 232 | ua.length++; |
| 233 | } |
| 234 | |
| 235 | done: |
| 236 | error = copyout(&ua, args, sizeof(struct i386_ioperm_args)); |
| 237 | return (error); |
| 238 | } |
| 239 | |
| 240 | #ifdef USER_LDT |
| 241 | /* |
| 242 | * Update the GDT entry pointing to the LDT to point to the LDT of the |
| 243 | * current process. Do not staticize. |
| 244 | */ |
| 245 | void |
| 246 | set_user_ldt(struct pcb *pcb) |
| 247 | { |
| 248 | struct pcb_ldt *pcb_ldt; |
| 249 | |
| 250 | if (pcb != curthread->td_pcb) |
| 251 | return; |
| 252 | |
| 253 | pcb_ldt = pcb->pcb_ldt; |
| 254 | #ifdef SMP |
| 255 | gdt[mycpu->gd_cpuid * NGDT + GUSERLDT_SEL].sd = pcb_ldt->ldt_sd; |
| 256 | #else |
| 257 | gdt[GUSERLDT_SEL].sd = pcb_ldt->ldt_sd; |
| 258 | #endif |
| 259 | lldt(GSEL(GUSERLDT_SEL, SEL_KPL)); |
| 260 | mdcpu->gd_currentldt = GSEL(GUSERLDT_SEL, SEL_KPL); |
| 261 | } |
| 262 | |
| 263 | struct pcb_ldt * |
| 264 | user_ldt_alloc(struct pcb *pcb, int len) |
| 265 | { |
| 266 | struct pcb_ldt *pcb_ldt, *new_ldt; |
| 267 | |
| 268 | MALLOC(new_ldt, struct pcb_ldt *, sizeof(struct pcb_ldt), |
| 269 | M_SUBPROC, M_WAITOK); |
| 270 | if (new_ldt == NULL) |
| 271 | return NULL; |
| 272 | |
| 273 | new_ldt->ldt_len = len = NEW_MAX_LD(len); |
| 274 | new_ldt->ldt_base = (caddr_t)kmem_alloc(kernel_map, |
| 275 | len * sizeof(union descriptor)); |
| 276 | if (new_ldt->ldt_base == NULL) { |
| 277 | FREE(new_ldt, M_SUBPROC); |
| 278 | return NULL; |
| 279 | } |
| 280 | new_ldt->ldt_refcnt = 1; |
| 281 | new_ldt->ldt_active = 0; |
| 282 | |
| 283 | gdt_segs[GUSERLDT_SEL].ssd_base = (unsigned)new_ldt->ldt_base; |
| 284 | gdt_segs[GUSERLDT_SEL].ssd_limit = len * sizeof(union descriptor) - 1; |
| 285 | ssdtosd(&gdt_segs[GUSERLDT_SEL], &new_ldt->ldt_sd); |
| 286 | |
| 287 | if ((pcb_ldt = pcb->pcb_ldt)) { |
| 288 | if (len > pcb_ldt->ldt_len) |
| 289 | len = pcb_ldt->ldt_len; |
| 290 | bcopy(pcb_ldt->ldt_base, new_ldt->ldt_base, |
| 291 | len * sizeof(union descriptor)); |
| 292 | } else { |
| 293 | bcopy(ldt, new_ldt->ldt_base, sizeof(ldt)); |
| 294 | } |
| 295 | return new_ldt; |
| 296 | } |
| 297 | |
| 298 | void |
| 299 | user_ldt_free(struct pcb *pcb) |
| 300 | { |
| 301 | struct pcb_ldt *pcb_ldt = pcb->pcb_ldt; |
| 302 | |
| 303 | if (pcb_ldt == NULL) |
| 304 | return; |
| 305 | |
| 306 | if (pcb == curthread->td_pcb) { |
| 307 | lldt(_default_ldt); |
| 308 | mdcpu->gd_currentldt = _default_ldt; |
| 309 | } |
| 310 | |
| 311 | if (--pcb_ldt->ldt_refcnt == 0) { |
| 312 | kmem_free(kernel_map, (vm_offset_t)pcb_ldt->ldt_base, |
| 313 | pcb_ldt->ldt_len * sizeof(union descriptor)); |
| 314 | FREE(pcb_ldt, M_SUBPROC); |
| 315 | } |
| 316 | pcb->pcb_ldt = NULL; |
| 317 | } |
| 318 | |
| 319 | static int |
| 320 | i386_get_ldt(struct proc *p, char *args, int *res) |
| 321 | { |
| 322 | int error = 0; |
| 323 | struct pcb *pcb = p->p_thread->td_pcb; |
| 324 | struct pcb_ldt *pcb_ldt = pcb->pcb_ldt; |
| 325 | int nldt, num; |
| 326 | union descriptor *lp; |
| 327 | int s; |
| 328 | struct i386_ldt_args ua, *uap = &ua; |
| 329 | |
| 330 | if ((error = copyin(args, uap, sizeof(struct i386_ldt_args))) < 0) |
| 331 | return(error); |
| 332 | |
| 333 | #ifdef DEBUG |
| 334 | printf("i386_get_ldt: start=%d num=%d descs=%p\n", |
| 335 | uap->start, uap->num, (void *)uap->descs); |
| 336 | #endif |
| 337 | |
| 338 | /* verify range of LDTs exist */ |
| 339 | if ((uap->start < 0) || (uap->num <= 0)) |
| 340 | return(EINVAL); |
| 341 | |
| 342 | s = splhigh(); |
| 343 | |
| 344 | if (pcb_ldt) { |
| 345 | nldt = pcb_ldt->ldt_len; |
| 346 | num = min(uap->num, nldt); |
| 347 | lp = &((union descriptor *)(pcb_ldt->ldt_base))[uap->start]; |
| 348 | } else { |
| 349 | nldt = sizeof(ldt)/sizeof(ldt[0]); |
| 350 | num = min(uap->num, nldt); |
| 351 | lp = &ldt[uap->start]; |
| 352 | } |
| 353 | if (uap->start + num > nldt) { |
| 354 | splx(s); |
| 355 | return(EINVAL); |
| 356 | } |
| 357 | |
| 358 | error = copyout(lp, uap->descs, num * sizeof(union descriptor)); |
| 359 | if (!error) |
| 360 | *res = num; |
| 361 | splx(s); |
| 362 | return(error); |
| 363 | } |
| 364 | |
| 365 | static int |
| 366 | i386_set_ldt(struct proc *p, char *args, int *res) |
| 367 | { |
| 368 | int error = 0, i, n; |
| 369 | int largest_ld; |
| 370 | struct pcb *pcb = p->p_thread->td_pcb; |
| 371 | struct pcb_ldt *pcb_ldt = pcb->pcb_ldt; |
| 372 | union descriptor *descs; |
| 373 | int descs_size, s; |
| 374 | struct i386_ldt_args ua, *uap = &ua; |
| 375 | |
| 376 | if ((error = copyin(args, uap, sizeof(struct i386_ldt_args))) < 0) |
| 377 | return(error); |
| 378 | |
| 379 | #ifdef DEBUG |
| 380 | printf("i386_set_ldt: start=%d num=%d descs=%p\n", |
| 381 | uap->start, uap->num, (void *)uap->descs); |
| 382 | #endif |
| 383 | |
| 384 | /* verify range of descriptors to modify */ |
| 385 | if ((uap->start < 0) || (uap->start >= MAX_LD) || (uap->num < 0) || |
| 386 | (uap->num > MAX_LD)) |
| 387 | { |
| 388 | return(EINVAL); |
| 389 | } |
| 390 | largest_ld = uap->start + uap->num - 1; |
| 391 | if (largest_ld >= MAX_LD) |
| 392 | return(EINVAL); |
| 393 | |
| 394 | /* allocate user ldt */ |
| 395 | if (!pcb_ldt || largest_ld >= pcb_ldt->ldt_len) { |
| 396 | struct pcb_ldt *new_ldt = user_ldt_alloc(pcb, largest_ld); |
| 397 | if (new_ldt == NULL) |
| 398 | return ENOMEM; |
| 399 | if (pcb_ldt) { |
| 400 | pcb_ldt->ldt_sd = new_ldt->ldt_sd; |
| 401 | kmem_free(kernel_map, (vm_offset_t)pcb_ldt->ldt_base, |
| 402 | pcb_ldt->ldt_len * sizeof(union descriptor)); |
| 403 | pcb_ldt->ldt_base = new_ldt->ldt_base; |
| 404 | pcb_ldt->ldt_len = new_ldt->ldt_len; |
| 405 | FREE(new_ldt, M_SUBPROC); |
| 406 | } else |
| 407 | pcb->pcb_ldt = pcb_ldt = new_ldt; |
| 408 | #ifdef SMP |
| 409 | /* signal other cpus to reload ldt */ |
| 410 | smp_rendezvous(NULL, (void (*)(void *))set_user_ldt, NULL, pcb); |
| 411 | #else |
| 412 | set_user_ldt(pcb); |
| 413 | #endif |
| 414 | } |
| 415 | |
| 416 | descs_size = uap->num * sizeof(union descriptor); |
| 417 | descs = (union descriptor *)kmem_alloc(kernel_map, descs_size); |
| 418 | if (descs == NULL) |
| 419 | return (ENOMEM); |
| 420 | error = copyin(&uap->descs[0], descs, descs_size); |
| 421 | if (error) { |
| 422 | kmem_free(kernel_map, (vm_offset_t)descs, descs_size); |
| 423 | return (error); |
| 424 | } |
| 425 | /* Check descriptors for access violations */ |
| 426 | for (i = 0, n = uap->start; i < uap->num; i++, n++) { |
| 427 | union descriptor *dp; |
| 428 | dp = &descs[i]; |
| 429 | |
| 430 | switch (dp->sd.sd_type) { |
| 431 | case SDT_SYSNULL: /* system null */ |
| 432 | dp->sd.sd_p = 0; |
| 433 | break; |
| 434 | case SDT_SYS286TSS: /* system 286 TSS available */ |
| 435 | case SDT_SYSLDT: /* system local descriptor table */ |
| 436 | case SDT_SYS286BSY: /* system 286 TSS busy */ |
| 437 | case SDT_SYSTASKGT: /* system task gate */ |
| 438 | case SDT_SYS286IGT: /* system 286 interrupt gate */ |
| 439 | case SDT_SYS286TGT: /* system 286 trap gate */ |
| 440 | case SDT_SYSNULL2: /* undefined by Intel */ |
| 441 | case SDT_SYS386TSS: /* system 386 TSS available */ |
| 442 | case SDT_SYSNULL3: /* undefined by Intel */ |
| 443 | case SDT_SYS386BSY: /* system 386 TSS busy */ |
| 444 | case SDT_SYSNULL4: /* undefined by Intel */ |
| 445 | case SDT_SYS386IGT: /* system 386 interrupt gate */ |
| 446 | case SDT_SYS386TGT: /* system 386 trap gate */ |
| 447 | case SDT_SYS286CGT: /* system 286 call gate */ |
| 448 | case SDT_SYS386CGT: /* system 386 call gate */ |
| 449 | /* I can't think of any reason to allow a user proc |
| 450 | * to create a segment of these types. They are |
| 451 | * for OS use only. |
| 452 | */ |
| 453 | kmem_free(kernel_map, (vm_offset_t)descs, descs_size); |
| 454 | return EACCES; |
| 455 | |
| 456 | /* memory segment types */ |
| 457 | case SDT_MEMEC: /* memory execute only conforming */ |
| 458 | case SDT_MEMEAC: /* memory execute only accessed conforming */ |
| 459 | case SDT_MEMERC: /* memory execute read conforming */ |
| 460 | case SDT_MEMERAC: /* memory execute read accessed conforming */ |
| 461 | /* Must be "present" if executable and conforming. */ |
| 462 | if (dp->sd.sd_p == 0) { |
| 463 | kmem_free(kernel_map, (vm_offset_t)descs, |
| 464 | descs_size); |
| 465 | return (EACCES); |
| 466 | } |
| 467 | break; |
| 468 | case SDT_MEMRO: /* memory read only */ |
| 469 | case SDT_MEMROA: /* memory read only accessed */ |
| 470 | case SDT_MEMRW: /* memory read write */ |
| 471 | case SDT_MEMRWA: /* memory read write accessed */ |
| 472 | case SDT_MEMROD: /* memory read only expand dwn limit */ |
| 473 | case SDT_MEMRODA: /* memory read only expand dwn lim accessed */ |
| 474 | case SDT_MEMRWD: /* memory read write expand dwn limit */ |
| 475 | case SDT_MEMRWDA: /* memory read write expand dwn lim acessed */ |
| 476 | case SDT_MEME: /* memory execute only */ |
| 477 | case SDT_MEMEA: /* memory execute only accessed */ |
| 478 | case SDT_MEMER: /* memory execute read */ |
| 479 | case SDT_MEMERA: /* memory execute read accessed */ |
| 480 | break; |
| 481 | default: |
| 482 | kmem_free(kernel_map, (vm_offset_t)descs, descs_size); |
| 483 | return(EINVAL); |
| 484 | /*NOTREACHED*/ |
| 485 | } |
| 486 | |
| 487 | /* Only user (ring-3) descriptors may be present. */ |
| 488 | if ((dp->sd.sd_p != 0) && (dp->sd.sd_dpl != SEL_UPL)) { |
| 489 | kmem_free(kernel_map, (vm_offset_t)descs, descs_size); |
| 490 | return (EACCES); |
| 491 | } |
| 492 | } |
| 493 | |
| 494 | s = splhigh(); |
| 495 | |
| 496 | /* Fill in range */ |
| 497 | bcopy(descs, |
| 498 | &((union descriptor *)(pcb_ldt->ldt_base))[uap->start], |
| 499 | uap->num * sizeof(union descriptor)); |
| 500 | *res = uap->start; |
| 501 | |
| 502 | splx(s); |
| 503 | kmem_free(kernel_map, (vm_offset_t)descs, descs_size); |
| 504 | return (0); |
| 505 | } |
| 506 | #endif /* USER_LDT */ |