linux_exec_elf32.c revision 1.11
1 /* $NetBSD: linux_exec_elf32.c,v 1.11 1995/09/19 22:37:27 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Frank van der Linden 5 * Copyright (c) 1994 Christos Zoulas 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. 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 ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * based on exec_aout.c, sunos_exec.c and svr4_exec.c 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/proc.h> 37 #include <sys/malloc.h> 38 #include <sys/namei.h> 39 #include <sys/vnode.h> 40 #include <sys/exec_elf.h> 41 42 #include <sys/mman.h> 43 #include <vm/vm.h> 44 #include <vm/vm_param.h> 45 #include <vm/vm_map.h> 46 47 #include <machine/cpu.h> 48 #include <machine/reg.h> 49 #include <machine/exec.h> 50 #include <machine/linux_machdep.h> 51 52 #include <compat/linux/linux_types.h> 53 #include <compat/linux/linux_syscall.h> 54 #include <compat/linux/linux_signal.h> 55 #include <compat/linux/linux_syscallargs.h> 56 #include <compat/linux/linux_util.h> 57 #include <compat/linux/linux_exec.h> 58 59 static void *linux_aout_copyargs __P((struct exec_package *, 60 struct ps_strings *, void *, void *)); 61 62 #define LINUX_AOUT_AUX_ARGSIZ 2 63 #define LINUX_ELF_AUX_ARGSIZ (sizeof(AuxInfo) * 8 / sizeof(char *)) 64 65 66 const char linux_emul_path[] = "/emul/linux"; 67 extern int linux_error[]; 68 extern struct sysent linux_sysent[]; 69 extern char *linux_syscallnames[]; 70 71 struct emul emul_linux_aout = { 72 "linux", 73 linux_error, 74 linux_sendsig, 75 LINUX_SYS_syscall, 76 LINUX_SYS_MAXSYSCALL, 77 linux_sysent, 78 linux_syscallnames, 79 LINUX_AOUT_AUX_ARGSIZ, 80 linux_aout_copyargs, 81 setregs, 82 linux_sigcode, 83 linux_esigcode, 84 }; 85 86 struct emul emul_linux_elf = { 87 "linux", 88 linux_error, 89 linux_sendsig, 90 LINUX_SYS_syscall, 91 LINUX_SYS_MAXSYSCALL, 92 linux_sysent, 93 linux_syscallnames, 94 LINUX_ELF_AUX_ARGSIZ, 95 elf_copyargs, 96 setregs, 97 linux_sigcode, 98 linux_esigcode, 99 }; 100 101 102 static void * 103 linux_aout_copyargs(pack, arginfo, stack, argp) 104 struct exec_package *pack; 105 struct ps_strings *arginfo; 106 void *stack; 107 void *argp; 108 { 109 char **cpp = stack; 110 char **stk = stack; 111 char *dp, *sp; 112 size_t len; 113 void *nullp = NULL; 114 int argc = arginfo->ps_nargvstr; 115 int envc = arginfo->ps_nenvstr; 116 117 if (copyout(&argc, cpp++, sizeof(argc))) 118 return NULL; 119 120 /* leave room for envp and argv */ 121 cpp += 2; 122 if (copyout(&cpp, &stk[1], sizeof (cpp))) 123 return NULL; 124 125 dp = (char *) (cpp + argc + envc + 2); 126 sp = argp; 127 128 /* XXX don't copy them out, remap them! */ 129 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 130 131 for (; --argc >= 0; sp += len, dp += len) 132 if (copyout(&dp, cpp++, sizeof(dp)) || 133 copyoutstr(sp, dp, ARG_MAX, &len)) 134 return NULL; 135 136 if (copyout(&nullp, cpp++, sizeof(nullp))) 137 return NULL; 138 139 if (copyout(&cpp, &stk[2], sizeof (cpp))) 140 return NULL; 141 142 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 143 144 for (; --envc >= 0; sp += len, dp += len) 145 if (copyout(&dp, cpp++, sizeof(dp)) || 146 copyoutstr(sp, dp, ARG_MAX, &len)) 147 return NULL; 148 149 if (copyout(&nullp, cpp++, sizeof(nullp))) 150 return NULL; 151 152 return cpp; 153 } 154 155 int 156 exec_linux_aout_makecmds(p, epp) 157 struct proc *p; 158 struct exec_package *epp; 159 { 160 struct exec *linux_ep = epp->ep_hdr; 161 int machtype, magic; 162 int error = ENOEXEC; 163 164 magic = LINUX_N_MAGIC(linux_ep); 165 machtype = LINUX_N_MACHTYPE(linux_ep); 166 167 168 if (machtype != LINUX_MID_MACHINE) 169 return (ENOEXEC); 170 171 switch (magic) { 172 case QMAGIC: 173 error = exec_linux_aout_prep_qmagic(p, epp); 174 break; 175 case ZMAGIC: 176 error = exec_linux_aout_prep_zmagic(p, epp); 177 break; 178 case NMAGIC: 179 error = exec_linux_aout_prep_nmagic(p, epp); 180 break; 181 case OMAGIC: 182 error = exec_linux_aout_prep_omagic(p, epp); 183 break; 184 } 185 if (error == 0) 186 epp->ep_emul = &emul_linux_aout; 187 return error; 188 } 189 190 /* 191 * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400 192 * is very likely not page aligned on most architectures, it is treated 193 * as an NMAGIC here. XXX 194 */ 195 196 int 197 exec_linux_aout_prep_zmagic(p, epp) 198 struct proc *p; 199 struct exec_package *epp; 200 { 201 struct exec *execp = epp->ep_hdr; 202 203 epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC); 204 epp->ep_tsize = execp->a_text; 205 epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC); 206 epp->ep_dsize = execp->a_data + execp->a_bss; 207 epp->ep_entry = execp->a_entry; 208 209 /* set up command for text segment */ 210 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text, 211 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC), 212 VM_PROT_READ|VM_PROT_EXECUTE); 213 214 /* set up command for data segment */ 215 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data, 216 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC), 217 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 218 219 /* set up command for bss segment */ 220 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss, 221 epp->ep_daddr + execp->a_data, NULLVP, 0, 222 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 223 224 return exec_aout_setup_stack(p, epp); 225 } 226 227 /* 228 * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package. 229 * Not different from the normal stuff. 230 */ 231 232 int 233 exec_linux_aout_prep_nmagic(p, epp) 234 struct proc *p; 235 struct exec_package *epp; 236 { 237 struct exec *execp = epp->ep_hdr; 238 long bsize, baddr; 239 240 epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC); 241 epp->ep_tsize = execp->a_text; 242 epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC); 243 epp->ep_dsize = execp->a_data + execp->a_bss; 244 epp->ep_entry = execp->a_entry; 245 246 /* set up command for text segment */ 247 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text, 248 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC), 249 VM_PROT_READ|VM_PROT_EXECUTE); 250 251 /* set up command for data segment */ 252 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data, 253 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC), 254 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 255 256 /* set up command for bss segment */ 257 baddr = roundup(epp->ep_daddr + execp->a_data, NBPG); 258 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 259 if (bsize > 0) 260 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 261 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 262 263 return exec_aout_setup_stack(p, epp); 264 } 265 266 /* 267 * exec_aout_prep_omagic(): Prepare Linux OMAGIC package. 268 * Business as usual. 269 */ 270 271 int 272 exec_linux_aout_prep_omagic(p, epp) 273 struct proc *p; 274 struct exec_package *epp; 275 { 276 struct exec *execp = epp->ep_hdr; 277 long dsize, bsize, baddr; 278 279 epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC); 280 epp->ep_tsize = execp->a_text; 281 epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC); 282 epp->ep_dsize = execp->a_data + execp->a_bss; 283 epp->ep_entry = execp->a_entry; 284 285 /* set up command for text and data segments */ 286 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, 287 execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp, 288 LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 289 290 /* set up command for bss segment */ 291 baddr = roundup(epp->ep_daddr + execp->a_data, NBPG); 292 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 293 if (bsize > 0) 294 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 295 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 296 297 /* 298 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize); 299 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are 300 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize' 301 * respectively to page boundaries. 302 * Compensate `ep_dsize' for the amount of data covered by the last 303 * text page. 304 */ 305 dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text, NBPG); 306 epp->ep_dsize = (dsize > 0) ? dsize : 0; 307 return exec_aout_setup_stack(p, epp); 308 } 309 310 int 311 exec_linux_aout_prep_qmagic(p, epp) 312 struct proc *p; 313 struct exec_package *epp; 314 { 315 struct exec *execp = epp->ep_hdr; 316 317 epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC); 318 epp->ep_tsize = execp->a_text; 319 epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC); 320 epp->ep_dsize = execp->a_data + execp->a_bss; 321 epp->ep_entry = execp->a_entry; 322 323 /* 324 * check if vnode is in open for writing, because we want to 325 * demand-page out of it. if it is, don't do it, for various 326 * reasons 327 */ 328 if ((execp->a_text != 0 || execp->a_data != 0) && 329 epp->ep_vp->v_writecount != 0) { 330 #ifdef DIAGNOSTIC 331 if (epp->ep_vp->v_flag & VTEXT) 332 panic("exec: a VTEXT vnode has writecount != 0\n"); 333 #endif 334 return ETXTBSY; 335 } 336 epp->ep_vp->v_flag |= VTEXT; 337 338 /* set up command for text segment */ 339 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text, 340 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC), 341 VM_PROT_READ|VM_PROT_EXECUTE); 342 343 /* set up command for data segment */ 344 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data, 345 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC), 346 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 347 348 /* set up command for bss segment */ 349 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss, 350 epp->ep_daddr + execp->a_data, NULLVP, 0, 351 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 352 353 return exec_aout_setup_stack(p, epp); 354 } 355 356 int 357 linux_elf_probe(p, epp, itp, pos) 358 struct proc *p; 359 struct exec_package *epp; 360 char *itp; 361 u_long *pos; 362 { 363 char *bp; 364 int error; 365 size_t len; 366 367 if (itp[0]) { 368 if ((error = emul_find(p, NULL, linux_emul_path, itp, &bp, 0))) 369 return error; 370 if ((error = copystr(bp, itp, MAXPATHLEN, &len))) 371 return error; 372 free(bp, M_TEMP); 373 } 374 epp->ep_emul = &emul_linux_elf; 375 *pos = ELF32_NO_ADDR; 376 return 0; 377 } 378 379 /* 380 * The Linux system call to load shared libraries, a.out version. The 381 * a.out shared libs are just files that are mapped onto a fixed 382 * address in the process' address space. The address is given in 383 * a_entry. Read in the header, set up some VM commands and run them. 384 * 385 * Yes, both text and data are mapped at once, so we're left with 386 * writeable text for the shared libs. The Linux crt0 seemed to break 387 * sometimes when data was mapped seperately. It munmapped a uselib() 388 * of ld.so by hand, which failed with shared text and data for ld.so 389 * Yuck. 390 * 391 * Because of the problem with ZMAGIC executables (text starts 392 * at 0x400 in the file, but needs to be mapped at 0), ZMAGIC 393 * shared libs are not handled very efficiently :-( 394 */ 395 396 int 397 linux_uselib(p, v, retval) 398 struct proc *p; 399 void *v; 400 register_t *retval; 401 { 402 struct linux_uselib_args /* { 403 syscallarg(char *) path; 404 } */ *uap = v; 405 caddr_t sg; 406 long bsize, dsize, tsize, taddr, baddr, daddr; 407 struct nameidata ni; 408 struct vnode *vp; 409 struct exec hdr; 410 struct exec_vmcmd_set vcset; 411 int rem, i, magic, error; 412 413 sg = stackgap_init(p->p_emul); 414 LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path)); 415 416 NDINIT(&ni, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), p); 417 418 if ((error = namei(&ni))) 419 return error; 420 421 vp = ni.ni_vp; 422 423 if ((error = vn_rdwr(UIO_READ, vp, (caddr_t) &hdr, LINUX_AOUT_HDR_SIZE, 424 0, UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, 425 &rem, p))) { 426 vrele(vp); 427 return error; 428 } 429 430 if (rem != 0) { 431 vrele(vp); 432 return ENOEXEC; 433 } 434 435 if (LINUX_N_MACHTYPE(&hdr) != LINUX_MID_MACHINE) 436 return ENOEXEC; 437 438 magic = LINUX_N_MAGIC(&hdr); 439 taddr = hdr.a_entry & (~(NBPG - 1)); 440 tsize = hdr.a_text; 441 daddr = taddr + tsize; 442 dsize = hdr.a_data + hdr.a_bss; 443 444 if ((hdr.a_text != 0 || hdr.a_data != 0) && vp->v_writecount != 0) { 445 vrele(vp); 446 return ETXTBSY; 447 } 448 vp->v_flag |= VTEXT; 449 450 vcset.evs_cnt = 0; 451 vcset.evs_used = 0; 452 453 NEW_VMCMD(&vcset, 454 magic == ZMAGIC ? vmcmd_map_readvn : vmcmd_map_pagedvn, 455 hdr.a_text + hdr.a_data, taddr, 456 vp, LINUX_N_TXTOFF(hdr, magic), 457 VM_PROT_READ|VM_PROT_EXECUTE|VM_PROT_WRITE); 458 459 baddr = roundup(daddr + hdr.a_data, NBPG); 460 bsize = daddr + dsize - baddr; 461 if (bsize > 0) { 462 NEW_VMCMD(&vcset, vmcmd_map_zero, bsize, baddr, 463 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 464 } 465 466 for (i = 0; i < vcset.evs_used && !error; i++) { 467 struct exec_vmcmd *vcp; 468 469 vcp = &vcset.evs_cmds[i]; 470 error = (*vcp->ev_proc)(p, vcp); 471 } 472 473 kill_vmcmds(&vcset); 474 475 vrele(vp); 476 477 return error; 478 } 479 480 /* 481 * Execve(2). Just check the alternate emulation path, and pass it on 482 * to the NetBSD execve(). 483 */ 484 int 485 linux_execve(p, v, retval) 486 struct proc *p; 487 void *v; 488 register_t *retval; 489 { 490 struct linux_execve_args /* { 491 syscallarg(char *) path; 492 syscallarg(char **) argv; 493 syscallarg(char **) envp; 494 } */ *uap = v; 495 caddr_t sg; 496 497 sg = stackgap_init(p->p_emul); 498 LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path)); 499 500 return execve(p, uap, retval); 501 } 502
Indexes created Mon Sep 22 05:09:51 GMT 2025