linux_sysvec.c revision 346827
1/*- 2 * Copyright (c) 1994-1996 S��ren Schmidt 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 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29#include <sys/cdefs.h> 30__FBSDID("$FreeBSD: stable/11/sys/i386/linux/linux_sysvec.c 346827 2019-04-28 13:40:17Z dchagin $"); 31 32#include <sys/param.h> 33#include <sys/systm.h> 34#include <sys/exec.h> 35#include <sys/fcntl.h> 36#include <sys/imgact.h> 37#include <sys/imgact_aout.h> 38#include <sys/imgact_elf.h> 39#include <sys/kernel.h> 40#include <sys/lock.h> 41#include <sys/malloc.h> 42#include <sys/module.h> 43#include <sys/mutex.h> 44#include <sys/proc.h> 45#include <sys/signalvar.h> 46#include <sys/syscallsubr.h> 47#include <sys/sysctl.h> 48#include <sys/sysent.h> 49#include <sys/sysproto.h> 50#include <sys/vnode.h> 51#include <sys/eventhandler.h> 52 53#include <vm/vm.h> 54#include <vm/pmap.h> 55#include <vm/vm_extern.h> 56#include <vm/vm_map.h> 57#include <vm/vm_object.h> 58#include <vm/vm_page.h> 59#include <vm/vm_param.h> 60 61#include <machine/cpu.h> 62#include <machine/cputypes.h> 63#include <machine/md_var.h> 64#include <machine/pcb.h> 65 66#include <i386/linux/linux.h> 67#include <i386/linux/linux_proto.h> 68#include <compat/linux/linux_emul.h> 69#include <compat/linux/linux_futex.h> 70#include <compat/linux/linux_ioctl.h> 71#include <compat/linux/linux_mib.h> 72#include <compat/linux/linux_misc.h> 73#include <compat/linux/linux_signal.h> 74#include <compat/linux/linux_util.h> 75#include <compat/linux/linux_vdso.h> 76 77MODULE_VERSION(linux, 1); 78 79#if BYTE_ORDER == LITTLE_ENDIAN 80#define SHELLMAGIC 0x2123 /* #! */ 81#else 82#define SHELLMAGIC 0x2321 83#endif 84 85#if defined(DEBUG) 86SYSCTL_PROC(_compat_linux, OID_AUTO, debug, CTLTYPE_STRING | CTLFLAG_RW, 0, 0, 87 linux_sysctl_debug, "A", "Linux debugging control"); 88#endif 89 90/* 91 * Allow the sendsig functions to use the ldebug() facility even though they 92 * are not syscalls themselves. Map them to syscall 0. This is slightly less 93 * bogus than using ldebug(sigreturn). 94 */ 95#define LINUX_SYS_linux_rt_sendsig 0 96#define LINUX_SYS_linux_sendsig 0 97 98#define LINUX_PS_STRINGS (LINUX_USRSTACK - sizeof(struct ps_strings)) 99 100static int linux_szsigcode; 101static vm_object_t linux_shared_page_obj; 102static char *linux_shared_page_mapping; 103extern char _binary_linux_locore_o_start; 104extern char _binary_linux_locore_o_end; 105 106extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 107 108SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 109 110static int linux_fixup(register_t **stack_base, 111 struct image_params *iparams); 112static int linux_fixup_elf(register_t **stack_base, 113 struct image_params *iparams); 114static void linux_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask); 115static int linux_exec_imgact_try(struct image_params *iparams); 116static void linux_exec_setregs(struct thread *td, 117 struct image_params *imgp, u_long stack); 118static register_t *linux_copyout_strings(struct image_params *imgp); 119static bool linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 120static void linux_vdso_install(void *param); 121static void linux_vdso_deinstall(void *param); 122 123static int linux_szplatform; 124const char *linux_kplatform; 125 126static eventhandler_tag linux_exit_tag; 127static eventhandler_tag linux_exec_tag; 128static eventhandler_tag linux_thread_dtor_tag; 129 130#define LINUX_T_UNKNOWN 255 131static int _bsd_to_linux_trapcode[] = { 132 LINUX_T_UNKNOWN, /* 0 */ 133 6, /* 1 T_PRIVINFLT */ 134 LINUX_T_UNKNOWN, /* 2 */ 135 3, /* 3 T_BPTFLT */ 136 LINUX_T_UNKNOWN, /* 4 */ 137 LINUX_T_UNKNOWN, /* 5 */ 138 16, /* 6 T_ARITHTRAP */ 139 254, /* 7 T_ASTFLT */ 140 LINUX_T_UNKNOWN, /* 8 */ 141 13, /* 9 T_PROTFLT */ 142 1, /* 10 T_TRCTRAP */ 143 LINUX_T_UNKNOWN, /* 11 */ 144 14, /* 12 T_PAGEFLT */ 145 LINUX_T_UNKNOWN, /* 13 */ 146 17, /* 14 T_ALIGNFLT */ 147 LINUX_T_UNKNOWN, /* 15 */ 148 LINUX_T_UNKNOWN, /* 16 */ 149 LINUX_T_UNKNOWN, /* 17 */ 150 0, /* 18 T_DIVIDE */ 151 2, /* 19 T_NMI */ 152 4, /* 20 T_OFLOW */ 153 5, /* 21 T_BOUND */ 154 7, /* 22 T_DNA */ 155 8, /* 23 T_DOUBLEFLT */ 156 9, /* 24 T_FPOPFLT */ 157 10, /* 25 T_TSSFLT */ 158 11, /* 26 T_SEGNPFLT */ 159 12, /* 27 T_STKFLT */ 160 18, /* 28 T_MCHK */ 161 19, /* 29 T_XMMFLT */ 162 15 /* 30 T_RESERVED */ 163}; 164#define bsd_to_linux_trapcode(code) \ 165 ((code)<nitems(_bsd_to_linux_trapcode)? \ 166 _bsd_to_linux_trapcode[(code)]: \ 167 LINUX_T_UNKNOWN) 168 169LINUX_VDSO_SYM_INTPTR(linux_sigcode); 170LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 171LINUX_VDSO_SYM_INTPTR(linux_vsyscall); 172 173/* 174 * If FreeBSD & Linux have a difference of opinion about what a trap 175 * means, deal with it here. 176 * 177 * MPSAFE 178 */ 179static int 180linux_translate_traps(int signal, int trap_code) 181{ 182 if (signal != SIGBUS) 183 return (signal); 184 switch (trap_code) { 185 case T_PROTFLT: 186 case T_TSSFLT: 187 case T_DOUBLEFLT: 188 case T_PAGEFLT: 189 return (SIGSEGV); 190 default: 191 return (signal); 192 } 193} 194 195static int 196linux_fixup(register_t **stack_base, struct image_params *imgp) 197{ 198 register_t *argv, *envp; 199 200 argv = *stack_base; 201 envp = *stack_base + (imgp->args->argc + 1); 202 (*stack_base)--; 203 suword(*stack_base, (intptr_t)(void *)envp); 204 (*stack_base)--; 205 suword(*stack_base, (intptr_t)(void *)argv); 206 (*stack_base)--; 207 suword(*stack_base, imgp->args->argc); 208 return (0); 209} 210 211static int 212linux_fixup_elf(register_t **stack_base, struct image_params *imgp) 213{ 214 struct proc *p; 215 Elf32_Auxargs *args; 216 Elf32_Addr *uplatform; 217 struct ps_strings *arginfo; 218 register_t *pos; 219 int issetugid; 220 221 KASSERT(curthread->td_proc == imgp->proc, 222 ("unsafe linux_fixup_elf(), should be curproc")); 223 224 p = imgp->proc; 225 issetugid = imgp->proc->p_flag & P_SUGID ? 1 : 0; 226 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 227 uplatform = (Elf32_Addr *)((caddr_t)arginfo - linux_szplatform); 228 args = (Elf32_Auxargs *)imgp->auxargs; 229 pos = *stack_base + (imgp->args->argc + imgp->args->envc + 2); 230 231 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 232 imgp->proc->p_sysent->sv_shared_page_base); 233 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO, linux_vsyscall); 234 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 235 236 /* 237 * Do not export AT_CLKTCK when emulating Linux kernel prior to 2.4.0, 238 * as it has appeared in the 2.4.0-rc7 first time. 239 * Being exported, AT_CLKTCK is returned by sysconf(_SC_CLK_TCK), 240 * glibc falls back to the hard-coded CLK_TCK value when aux entry 241 * is not present. 242 * Also see linux_times() implementation. 243 */ 244 if (linux_kernver(curthread) >= LINUX_KERNVER_2004000) 245 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 246 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 247 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 248 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 249 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 250 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 251 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 252 AUXARGS_ENTRY(pos, AT_BASE, args->base); 253 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 254 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 255 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 256 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 257 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 258 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(uplatform)); 259 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 260 if (imgp->execpathp != 0) 261 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 262 if (args->execfd != -1) 263 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 264 AUXARGS_ENTRY(pos, AT_NULL, 0); 265 266 free(imgp->auxargs, M_TEMP); 267 imgp->auxargs = NULL; 268 269 (*stack_base)--; 270 suword(*stack_base, (register_t)imgp->args->argc); 271 return (0); 272} 273 274/* 275 * Copied from kern/kern_exec.c 276 */ 277static register_t * 278linux_copyout_strings(struct image_params *imgp) 279{ 280 int argc, envc; 281 char **vectp; 282 char *stringp, *destp; 283 register_t *stack_base; 284 struct ps_strings *arginfo; 285 char canary[LINUX_AT_RANDOM_LEN]; 286 size_t execpath_len; 287 struct proc *p; 288 289 /* Calculate string base and vector table pointers. */ 290 p = imgp->proc; 291 if (imgp->execpath != NULL && imgp->auxargs != NULL) 292 execpath_len = strlen(imgp->execpath) + 1; 293 else 294 execpath_len = 0; 295 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 296 destp = (caddr_t)arginfo - SPARE_USRSPACE - linux_szplatform - 297 roundup(sizeof(canary), sizeof(char *)) - 298 roundup(execpath_len, sizeof(char *)) - 299 roundup(ARG_MAX - imgp->args->stringspace, sizeof(char *)); 300 301 /* Install LINUX_PLATFORM. */ 302 copyout(linux_kplatform, ((caddr_t)arginfo - linux_szplatform), 303 linux_szplatform); 304 305 if (execpath_len != 0) { 306 imgp->execpathp = (uintptr_t)arginfo - 307 linux_szplatform - execpath_len; 308 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 309 } 310 311 /* Prepare the canary for SSP. */ 312 arc4rand(canary, sizeof(canary), 0); 313 imgp->canary = (uintptr_t)arginfo - linux_szplatform - 314 roundup(execpath_len, sizeof(char *)) - 315 roundup(sizeof(canary), sizeof(char *)); 316 copyout(canary, (void *)imgp->canary, sizeof(canary)); 317 318 vectp = (char **)destp; 319 if (imgp->auxargs) { 320 /* 321 * Allocate room on the stack for the ELF auxargs 322 * array. It has LINUX_AT_COUNT entries. 323 */ 324 vectp -= howmany(LINUX_AT_COUNT * sizeof(Elf32_Auxinfo), 325 sizeof(*vectp)); 326 } 327 328 /* 329 * Allocate room for the argv[] and env vectors including the 330 * terminating NULL pointers. 331 */ 332 vectp -= imgp->args->argc + 1 + imgp->args->envc + 1; 333 334 /* vectp also becomes our initial stack base. */ 335 stack_base = (register_t *)vectp; 336 337 stringp = imgp->args->begin_argv; 338 argc = imgp->args->argc; 339 envc = imgp->args->envc; 340 341 /* Copy out strings - arguments and environment. */ 342 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 343 344 /* Fill in "ps_strings" struct for ps, w, etc. */ 345 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 346 suword(&arginfo->ps_nargvstr, argc); 347 348 /* Fill in argument portion of vector table. */ 349 for (; argc > 0; --argc) { 350 suword(vectp++, (long)(intptr_t)destp); 351 while (*stringp++ != 0) 352 destp++; 353 destp++; 354 } 355 356 /* A null vector table pointer separates the argp's from the envp's. */ 357 suword(vectp++, 0); 358 359 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 360 suword(&arginfo->ps_nenvstr, envc); 361 362 /* Fill in environment portion of vector table. */ 363 for (; envc > 0; --envc) { 364 suword(vectp++, (long)(intptr_t)destp); 365 while (*stringp++ != 0) 366 destp++; 367 destp++; 368 } 369 370 /* The end of the vector table is a null pointer. */ 371 suword(vectp, 0); 372 373 return (stack_base); 374} 375 376static void 377linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 378{ 379 struct thread *td = curthread; 380 struct proc *p = td->td_proc; 381 struct sigacts *psp; 382 struct trapframe *regs; 383 struct l_rt_sigframe *fp, frame; 384 int sig, code; 385 int oonstack; 386 387 sig = ksi->ksi_signo; 388 code = ksi->ksi_code; 389 PROC_LOCK_ASSERT(p, MA_OWNED); 390 psp = p->p_sigacts; 391 mtx_assert(&psp->ps_mtx, MA_OWNED); 392 regs = td->td_frame; 393 oonstack = sigonstack(regs->tf_esp); 394 395#ifdef DEBUG 396 if (ldebug(rt_sendsig)) 397 printf(ARGS(rt_sendsig, "%p, %d, %p, %u"), 398 catcher, sig, (void*)mask, code); 399#endif 400 /* Allocate space for the signal handler context. */ 401 if ((td->td_pflags & TDP_ALTSTACK) && !oonstack && 402 SIGISMEMBER(psp->ps_sigonstack, sig)) { 403 fp = (struct l_rt_sigframe *)((uintptr_t)td->td_sigstk.ss_sp + 404 td->td_sigstk.ss_size - sizeof(struct l_rt_sigframe)); 405 } else 406 fp = (struct l_rt_sigframe *)regs->tf_esp - 1; 407 mtx_unlock(&psp->ps_mtx); 408 409 /* Build the argument list for the signal handler. */ 410 sig = bsd_to_linux_signal(sig); 411 412 bzero(&frame, sizeof(frame)); 413 414 frame.sf_handler = catcher; 415 frame.sf_sig = sig; 416 frame.sf_siginfo = &fp->sf_si; 417 frame.sf_ucontext = &fp->sf_sc; 418 419 /* Fill in POSIX parts. */ 420 ksiginfo_to_lsiginfo(ksi, &frame.sf_si, sig); 421 422 /* Build the signal context to be used by sigreturn. */ 423 frame.sf_sc.uc_flags = 0; /* XXX ??? */ 424 frame.sf_sc.uc_link = NULL; /* XXX ??? */ 425 426 frame.sf_sc.uc_stack.ss_sp = td->td_sigstk.ss_sp; 427 frame.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 428 frame.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 429 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 430 PROC_UNLOCK(p); 431 432 bsd_to_linux_sigset(mask, &frame.sf_sc.uc_sigmask); 433 434 frame.sf_sc.uc_mcontext.sc_mask = frame.sf_sc.uc_sigmask.__mask; 435 frame.sf_sc.uc_mcontext.sc_gs = rgs(); 436 frame.sf_sc.uc_mcontext.sc_fs = regs->tf_fs; 437 frame.sf_sc.uc_mcontext.sc_es = regs->tf_es; 438 frame.sf_sc.uc_mcontext.sc_ds = regs->tf_ds; 439 frame.sf_sc.uc_mcontext.sc_edi = regs->tf_edi; 440 frame.sf_sc.uc_mcontext.sc_esi = regs->tf_esi; 441 frame.sf_sc.uc_mcontext.sc_ebp = regs->tf_ebp; 442 frame.sf_sc.uc_mcontext.sc_ebx = regs->tf_ebx; 443 frame.sf_sc.uc_mcontext.sc_esp = regs->tf_esp; 444 frame.sf_sc.uc_mcontext.sc_edx = regs->tf_edx; 445 frame.sf_sc.uc_mcontext.sc_ecx = regs->tf_ecx; 446 frame.sf_sc.uc_mcontext.sc_eax = regs->tf_eax; 447 frame.sf_sc.uc_mcontext.sc_eip = regs->tf_eip; 448 frame.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 449 frame.sf_sc.uc_mcontext.sc_eflags = regs->tf_eflags; 450 frame.sf_sc.uc_mcontext.sc_esp_at_signal = regs->tf_esp; 451 frame.sf_sc.uc_mcontext.sc_ss = regs->tf_ss; 452 frame.sf_sc.uc_mcontext.sc_err = regs->tf_err; 453 frame.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 454 frame.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 455 456#ifdef DEBUG 457 if (ldebug(rt_sendsig)) 458 printf(LMSG("rt_sendsig flags: 0x%x, sp: %p, ss: 0x%x, mask: 0x%x"), 459 frame.sf_sc.uc_stack.ss_flags, td->td_sigstk.ss_sp, 460 td->td_sigstk.ss_size, frame.sf_sc.uc_mcontext.sc_mask); 461#endif 462 463 if (copyout(&frame, fp, sizeof(frame)) != 0) { 464 /* 465 * Process has trashed its stack; give it an illegal 466 * instruction to halt it in its tracks. 467 */ 468#ifdef DEBUG 469 if (ldebug(rt_sendsig)) 470 printf(LMSG("rt_sendsig: bad stack %p, oonstack=%x"), 471 fp, oonstack); 472#endif 473 PROC_LOCK(p); 474 sigexit(td, SIGILL); 475 } 476 477 /* Build context to run handler in. */ 478 regs->tf_esp = (int)fp; 479 regs->tf_eip = linux_rt_sigcode; 480 regs->tf_eflags &= ~(PSL_T | PSL_VM | PSL_D); 481 regs->tf_cs = _ucodesel; 482 regs->tf_ds = _udatasel; 483 regs->tf_es = _udatasel; 484 regs->tf_fs = _udatasel; 485 regs->tf_ss = _udatasel; 486 PROC_LOCK(p); 487 mtx_lock(&psp->ps_mtx); 488} 489 490 491/* 492 * Send an interrupt to process. 493 * 494 * Stack is set up to allow sigcode stored 495 * in u. to call routine, followed by kcall 496 * to sigreturn routine below. After sigreturn 497 * resets the signal mask, the stack, and the 498 * frame pointer, it returns to the user 499 * specified pc, psl. 500 */ 501static void 502linux_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 503{ 504 struct thread *td = curthread; 505 struct proc *p = td->td_proc; 506 struct sigacts *psp; 507 struct trapframe *regs; 508 struct l_sigframe *fp, frame; 509 l_sigset_t lmask; 510 int sig, code; 511 int oonstack; 512 513 PROC_LOCK_ASSERT(p, MA_OWNED); 514 psp = p->p_sigacts; 515 sig = ksi->ksi_signo; 516 code = ksi->ksi_code; 517 mtx_assert(&psp->ps_mtx, MA_OWNED); 518 if (SIGISMEMBER(psp->ps_siginfo, sig)) { 519 /* Signal handler installed with SA_SIGINFO. */ 520 linux_rt_sendsig(catcher, ksi, mask); 521 return; 522 } 523 regs = td->td_frame; 524 oonstack = sigonstack(regs->tf_esp); 525 526#ifdef DEBUG 527 if (ldebug(sendsig)) 528 printf(ARGS(sendsig, "%p, %d, %p, %u"), 529 catcher, sig, (void*)mask, code); 530#endif 531 532 /* Allocate space for the signal handler context. */ 533 if ((td->td_pflags & TDP_ALTSTACK) && !oonstack && 534 SIGISMEMBER(psp->ps_sigonstack, sig)) { 535 fp = (struct l_sigframe *)((uintptr_t)td->td_sigstk.ss_sp + 536 td->td_sigstk.ss_size - sizeof(struct l_sigframe)); 537 } else 538 fp = (struct l_sigframe *)regs->tf_esp - 1; 539 mtx_unlock(&psp->ps_mtx); 540 PROC_UNLOCK(p); 541 542 /* Build the argument list for the signal handler. */ 543 sig = bsd_to_linux_signal(sig); 544 545 bzero(&frame, sizeof(frame)); 546 547 frame.sf_handler = catcher; 548 frame.sf_sig = sig; 549 550 bsd_to_linux_sigset(mask, &lmask); 551 552 /* Build the signal context to be used by sigreturn. */ 553 frame.sf_sc.sc_mask = lmask.__mask; 554 frame.sf_sc.sc_gs = rgs(); 555 frame.sf_sc.sc_fs = regs->tf_fs; 556 frame.sf_sc.sc_es = regs->tf_es; 557 frame.sf_sc.sc_ds = regs->tf_ds; 558 frame.sf_sc.sc_edi = regs->tf_edi; 559 frame.sf_sc.sc_esi = regs->tf_esi; 560 frame.sf_sc.sc_ebp = regs->tf_ebp; 561 frame.sf_sc.sc_ebx = regs->tf_ebx; 562 frame.sf_sc.sc_esp = regs->tf_esp; 563 frame.sf_sc.sc_edx = regs->tf_edx; 564 frame.sf_sc.sc_ecx = regs->tf_ecx; 565 frame.sf_sc.sc_eax = regs->tf_eax; 566 frame.sf_sc.sc_eip = regs->tf_eip; 567 frame.sf_sc.sc_cs = regs->tf_cs; 568 frame.sf_sc.sc_eflags = regs->tf_eflags; 569 frame.sf_sc.sc_esp_at_signal = regs->tf_esp; 570 frame.sf_sc.sc_ss = regs->tf_ss; 571 frame.sf_sc.sc_err = regs->tf_err; 572 frame.sf_sc.sc_cr2 = (register_t)ksi->ksi_addr; 573 frame.sf_sc.sc_trapno = bsd_to_linux_trapcode(ksi->ksi_trapno); 574 575 frame.sf_extramask[0] = lmask.__mask; 576 577 if (copyout(&frame, fp, sizeof(frame)) != 0) { 578 /* 579 * Process has trashed its stack; give it an illegal 580 * instruction to halt it in its tracks. 581 */ 582 PROC_LOCK(p); 583 sigexit(td, SIGILL); 584 } 585 586 /* Build context to run handler in. */ 587 regs->tf_esp = (int)fp; 588 regs->tf_eip = linux_sigcode; 589 regs->tf_eflags &= ~(PSL_T | PSL_VM | PSL_D); 590 regs->tf_cs = _ucodesel; 591 regs->tf_ds = _udatasel; 592 regs->tf_es = _udatasel; 593 regs->tf_fs = _udatasel; 594 regs->tf_ss = _udatasel; 595 PROC_LOCK(p); 596 mtx_lock(&psp->ps_mtx); 597} 598 599/* 600 * System call to cleanup state after a signal 601 * has been taken. Reset signal mask and 602 * stack state from context left by sendsig (above). 603 * Return to previous pc and psl as specified by 604 * context left by sendsig. Check carefully to 605 * make sure that the user has not modified the 606 * psl to gain improper privileges or to cause 607 * a machine fault. 608 */ 609int 610linux_sigreturn(struct thread *td, struct linux_sigreturn_args *args) 611{ 612 struct l_sigframe frame; 613 struct trapframe *regs; 614 l_sigset_t lmask; 615 sigset_t bmask; 616 int eflags; 617 ksiginfo_t ksi; 618 619 regs = td->td_frame; 620 621#ifdef DEBUG 622 if (ldebug(sigreturn)) 623 printf(ARGS(sigreturn, "%p"), (void *)args->sfp); 624#endif 625 /* 626 * The trampoline code hands us the sigframe. 627 * It is unsafe to keep track of it ourselves, in the event that a 628 * program jumps out of a signal handler. 629 */ 630 if (copyin(args->sfp, &frame, sizeof(frame)) != 0) 631 return (EFAULT); 632 633 /* Check for security violations. */ 634#define EFLAGS_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 635 eflags = frame.sf_sc.sc_eflags; 636 if (!EFLAGS_SECURE(eflags, regs->tf_eflags)) 637 return (EINVAL); 638 639 /* 640 * Don't allow users to load a valid privileged %cs. Let the 641 * hardware check for invalid selectors, excess privilege in 642 * other selectors, invalid %eip's and invalid %esp's. 643 */ 644#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 645 if (!CS_SECURE(frame.sf_sc.sc_cs)) { 646 ksiginfo_init_trap(&ksi); 647 ksi.ksi_signo = SIGBUS; 648 ksi.ksi_code = BUS_OBJERR; 649 ksi.ksi_trapno = T_PROTFLT; 650 ksi.ksi_addr = (void *)regs->tf_eip; 651 trapsignal(td, &ksi); 652 return (EINVAL); 653 } 654 655 lmask.__mask = frame.sf_sc.sc_mask; 656 linux_to_bsd_sigset(&lmask, &bmask); 657 kern_sigprocmask(td, SIG_SETMASK, &bmask, NULL, 0); 658 659 /* Restore signal context. */ 660 /* %gs was restored by the trampoline. */ 661 regs->tf_fs = frame.sf_sc.sc_fs; 662 regs->tf_es = frame.sf_sc.sc_es; 663 regs->tf_ds = frame.sf_sc.sc_ds; 664 regs->tf_edi = frame.sf_sc.sc_edi; 665 regs->tf_esi = frame.sf_sc.sc_esi; 666 regs->tf_ebp = frame.sf_sc.sc_ebp; 667 regs->tf_ebx = frame.sf_sc.sc_ebx; 668 regs->tf_edx = frame.sf_sc.sc_edx; 669 regs->tf_ecx = frame.sf_sc.sc_ecx; 670 regs->tf_eax = frame.sf_sc.sc_eax; 671 regs->tf_eip = frame.sf_sc.sc_eip; 672 regs->tf_cs = frame.sf_sc.sc_cs; 673 regs->tf_eflags = eflags; 674 regs->tf_esp = frame.sf_sc.sc_esp_at_signal; 675 regs->tf_ss = frame.sf_sc.sc_ss; 676 677 return (EJUSTRETURN); 678} 679 680/* 681 * System call to cleanup state after a signal 682 * has been taken. Reset signal mask and 683 * stack state from context left by rt_sendsig (above). 684 * Return to previous pc and psl as specified by 685 * context left by sendsig. Check carefully to 686 * make sure that the user has not modified the 687 * psl to gain improper privileges or to cause 688 * a machine fault. 689 */ 690int 691linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 692{ 693 struct l_ucontext uc; 694 struct l_sigcontext *context; 695 sigset_t bmask; 696 l_stack_t *lss; 697 stack_t ss; 698 struct trapframe *regs; 699 int eflags; 700 ksiginfo_t ksi; 701 702 regs = td->td_frame; 703 704#ifdef DEBUG 705 if (ldebug(rt_sigreturn)) 706 printf(ARGS(rt_sigreturn, "%p"), (void *)args->ucp); 707#endif 708 /* 709 * The trampoline code hands us the ucontext. 710 * It is unsafe to keep track of it ourselves, in the event that a 711 * program jumps out of a signal handler. 712 */ 713 if (copyin(args->ucp, &uc, sizeof(uc)) != 0) 714 return (EFAULT); 715 716 context = &uc.uc_mcontext; 717 718 /* Check for security violations. */ 719#define EFLAGS_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 720 eflags = context->sc_eflags; 721 if (!EFLAGS_SECURE(eflags, regs->tf_eflags)) 722 return (EINVAL); 723 724 /* 725 * Don't allow users to load a valid privileged %cs. Let the 726 * hardware check for invalid selectors, excess privilege in 727 * other selectors, invalid %eip's and invalid %esp's. 728 */ 729#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 730 if (!CS_SECURE(context->sc_cs)) { 731 ksiginfo_init_trap(&ksi); 732 ksi.ksi_signo = SIGBUS; 733 ksi.ksi_code = BUS_OBJERR; 734 ksi.ksi_trapno = T_PROTFLT; 735 ksi.ksi_addr = (void *)regs->tf_eip; 736 trapsignal(td, &ksi); 737 return (EINVAL); 738 } 739 740 linux_to_bsd_sigset(&uc.uc_sigmask, &bmask); 741 kern_sigprocmask(td, SIG_SETMASK, &bmask, NULL, 0); 742 743 /* Restore signal context. */ 744 /* %gs was restored by the trampoline. */ 745 regs->tf_fs = context->sc_fs; 746 regs->tf_es = context->sc_es; 747 regs->tf_ds = context->sc_ds; 748 regs->tf_edi = context->sc_edi; 749 regs->tf_esi = context->sc_esi; 750 regs->tf_ebp = context->sc_ebp; 751 regs->tf_ebx = context->sc_ebx; 752 regs->tf_edx = context->sc_edx; 753 regs->tf_ecx = context->sc_ecx; 754 regs->tf_eax = context->sc_eax; 755 regs->tf_eip = context->sc_eip; 756 regs->tf_cs = context->sc_cs; 757 regs->tf_eflags = eflags; 758 regs->tf_esp = context->sc_esp_at_signal; 759 regs->tf_ss = context->sc_ss; 760 761 /* Call sigaltstack & ignore results. */ 762 lss = &uc.uc_stack; 763 ss.ss_sp = lss->ss_sp; 764 ss.ss_size = lss->ss_size; 765 ss.ss_flags = linux_to_bsd_sigaltstack(lss->ss_flags); 766 767#ifdef DEBUG 768 if (ldebug(rt_sigreturn)) 769 printf(LMSG("rt_sigret flags: 0x%x, sp: %p, ss: 0x%x, mask: 0x%x"), 770 ss.ss_flags, ss.ss_sp, ss.ss_size, context->sc_mask); 771#endif 772 (void)kern_sigaltstack(td, &ss, NULL); 773 774 return (EJUSTRETURN); 775} 776 777static int 778linux_fetch_syscall_args(struct thread *td) 779{ 780 struct proc *p; 781 struct trapframe *frame; 782 struct syscall_args *sa; 783 784 p = td->td_proc; 785 frame = td->td_frame; 786 sa = &td->td_sa; 787 788 sa->code = frame->tf_eax; 789 sa->args[0] = frame->tf_ebx; 790 sa->args[1] = frame->tf_ecx; 791 sa->args[2] = frame->tf_edx; 792 sa->args[3] = frame->tf_esi; 793 sa->args[4] = frame->tf_edi; 794 sa->args[5] = frame->tf_ebp; /* Unconfirmed */ 795 796 if (sa->code >= p->p_sysent->sv_size) 797 /* nosys */ 798 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 799 else 800 sa->callp = &p->p_sysent->sv_table[sa->code]; 801 sa->narg = sa->callp->sy_narg; 802 803 td->td_retval[0] = 0; 804 td->td_retval[1] = frame->tf_edx; 805 806 return (0); 807} 808 809/* 810 * If a Linux binary is exec'ing something, try this image activator 811 * first. We override standard shell script execution in order to 812 * be able to modify the interpreter path. We only do this if a Linux 813 * binary is doing the exec, so we do not create an EXEC module for it. 814 */ 815static int 816linux_exec_imgact_try(struct image_params *imgp) 817{ 818 const char *head = (const char *)imgp->image_header; 819 char *rpath; 820 int error = -1; 821 822 /* 823 * The interpreter for shell scripts run from a Linux binary needs 824 * to be located in /compat/linux if possible in order to recursively 825 * maintain Linux path emulation. 826 */ 827 if (((const short *)head)[0] == SHELLMAGIC) { 828 /* 829 * Run our normal shell image activator. If it succeeds then 830 * attempt to use the alternate path for the interpreter. If 831 * an alternate path is found, use our stringspace to store it. 832 */ 833 if ((error = exec_shell_imgact(imgp)) == 0) { 834 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc), 835 imgp->interpreter_name, UIO_SYSSPACE, &rpath, 0, 836 AT_FDCWD); 837 if (rpath != NULL) 838 imgp->args->fname_buf = 839 imgp->interpreter_name = rpath; 840 } 841 } 842 return (error); 843} 844 845/* 846 * exec_setregs may initialize some registers differently than Linux 847 * does, thus potentially confusing Linux binaries. If necessary, we 848 * override the exec_setregs default(s) here. 849 */ 850static void 851linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 852{ 853 struct pcb *pcb = td->td_pcb; 854 855 exec_setregs(td, imgp, stack); 856 857 /* Linux sets %gs to 0, we default to _udatasel. */ 858 pcb->pcb_gs = 0; 859 load_gs(0); 860 861 pcb->pcb_initial_npxcw = __LINUX_NPXCW__; 862} 863 864static void 865linux_get_machine(const char **dst) 866{ 867 868 switch (cpu_class) { 869 case CPUCLASS_686: 870 *dst = "i686"; 871 break; 872 case CPUCLASS_586: 873 *dst = "i586"; 874 break; 875 case CPUCLASS_486: 876 *dst = "i486"; 877 break; 878 default: 879 *dst = "i386"; 880 } 881} 882 883struct sysentvec linux_sysvec = { 884 .sv_size = LINUX_SYS_MAXSYSCALL, 885 .sv_table = linux_sysent, 886 .sv_mask = 0, 887 .sv_errsize = ELAST + 1, 888 .sv_errtbl = linux_errtbl, 889 .sv_transtrap = linux_translate_traps, 890 .sv_fixup = linux_fixup, 891 .sv_sendsig = linux_sendsig, 892 .sv_sigcode = &_binary_linux_locore_o_start, 893 .sv_szsigcode = &linux_szsigcode, 894 .sv_name = "Linux a.out", 895 .sv_coredump = NULL, 896 .sv_imgact_try = linux_exec_imgact_try, 897 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 898 .sv_pagesize = PAGE_SIZE, 899 .sv_minuser = VM_MIN_ADDRESS, 900 .sv_maxuser = VM_MAXUSER_ADDRESS, 901 .sv_usrstack = LINUX_USRSTACK, 902 .sv_psstrings = PS_STRINGS, 903 .sv_stackprot = VM_PROT_ALL, 904 .sv_copyout_strings = exec_copyout_strings, 905 .sv_setregs = linux_exec_setregs, 906 .sv_fixlimit = NULL, 907 .sv_maxssiz = NULL, 908 .sv_flags = SV_ABI_LINUX | SV_AOUT | SV_IA32 | SV_ILP32, 909 .sv_set_syscall_retval = cpu_set_syscall_retval, 910 .sv_fetch_syscall_args = linux_fetch_syscall_args, 911 .sv_syscallnames = NULL, 912 .sv_shared_page_base = LINUX_SHAREDPAGE, 913 .sv_shared_page_len = PAGE_SIZE, 914 .sv_schedtail = linux_schedtail, 915 .sv_thread_detach = linux_thread_detach, 916 .sv_trap = NULL, 917}; 918INIT_SYSENTVEC(aout_sysvec, &linux_sysvec); 919 920struct sysentvec elf_linux_sysvec = { 921 .sv_size = LINUX_SYS_MAXSYSCALL, 922 .sv_table = linux_sysent, 923 .sv_mask = 0, 924 .sv_errsize = ELAST + 1, 925 .sv_errtbl = linux_errtbl, 926 .sv_transtrap = linux_translate_traps, 927 .sv_fixup = linux_fixup_elf, 928 .sv_sendsig = linux_sendsig, 929 .sv_sigcode = &_binary_linux_locore_o_start, 930 .sv_szsigcode = &linux_szsigcode, 931 .sv_name = "Linux ELF", 932 .sv_coredump = elf32_coredump, 933 .sv_imgact_try = linux_exec_imgact_try, 934 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 935 .sv_pagesize = PAGE_SIZE, 936 .sv_minuser = VM_MIN_ADDRESS, 937 .sv_maxuser = VM_MAXUSER_ADDRESS, 938 .sv_usrstack = LINUX_USRSTACK, 939 .sv_psstrings = LINUX_PS_STRINGS, 940 .sv_stackprot = VM_PROT_ALL, 941 .sv_copyout_strings = linux_copyout_strings, 942 .sv_setregs = linux_exec_setregs, 943 .sv_fixlimit = NULL, 944 .sv_maxssiz = NULL, 945 .sv_flags = SV_ABI_LINUX | SV_IA32 | SV_ILP32 | SV_SHP, 946 .sv_set_syscall_retval = cpu_set_syscall_retval, 947 .sv_fetch_syscall_args = linux_fetch_syscall_args, 948 .sv_syscallnames = NULL, 949 .sv_shared_page_base = LINUX_SHAREDPAGE, 950 .sv_shared_page_len = PAGE_SIZE, 951 .sv_schedtail = linux_schedtail, 952 .sv_thread_detach = linux_thread_detach, 953 .sv_trap = NULL, 954}; 955 956static void 957linux_vdso_install(void *param) 958{ 959 960 linux_szsigcode = (&_binary_linux_locore_o_end - 961 &_binary_linux_locore_o_start); 962 963 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 964 panic("Linux invalid vdso size\n"); 965 966 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 967 968 linux_shared_page_obj = __elfN(linux_shared_page_init) 969 (&linux_shared_page_mapping); 970 971 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 972 973 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 974 linux_szsigcode); 975 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 976} 977SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 978 (sysinit_cfunc_t)linux_vdso_install, NULL); 979 980static void 981linux_vdso_deinstall(void *param) 982{ 983 984 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 985} 986SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 987 (sysinit_cfunc_t)linux_vdso_deinstall, NULL); 988 989static char GNU_ABI_VENDOR[] = "GNU"; 990static int GNULINUX_ABI_DESC = 0; 991 992static bool 993linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 994{ 995 const Elf32_Word *desc; 996 uintptr_t p; 997 998 p = (uintptr_t)(note + 1); 999 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 1000 1001 desc = (const Elf32_Word *)p; 1002 if (desc[0] != GNULINUX_ABI_DESC) 1003 return (false); 1004 1005 /* 1006 * For Linux we encode osrel as follows (see linux_mib.c): 1007 * VVVMMMIII (version, major, minor), see linux_mib.c. 1008 */ 1009 *osrel = desc[1] * 1000000 + desc[2] * 1000 + desc[3]; 1010 1011 return (true); 1012} 1013 1014static Elf_Brandnote linux_brandnote = { 1015 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 1016 .hdr.n_descsz = 16, /* XXX at least 16 */ 1017 .hdr.n_type = 1, 1018 .vendor = GNU_ABI_VENDOR, 1019 .flags = BN_TRANSLATE_OSREL, 1020 .trans_osrel = linux_trans_osrel 1021}; 1022 1023static Elf32_Brandinfo linux_brand = { 1024 .brand = ELFOSABI_LINUX, 1025 .machine = EM_386, 1026 .compat_3_brand = "Linux", 1027 .emul_path = "/compat/linux", 1028 .interp_path = "/lib/ld-linux.so.1", 1029 .sysvec = &elf_linux_sysvec, 1030 .interp_newpath = NULL, 1031 .brand_note = &linux_brandnote, 1032 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 1033}; 1034 1035static Elf32_Brandinfo linux_glibc2brand = { 1036 .brand = ELFOSABI_LINUX, 1037 .machine = EM_386, 1038 .compat_3_brand = "Linux", 1039 .emul_path = "/compat/linux", 1040 .interp_path = "/lib/ld-linux.so.2", 1041 .sysvec = &elf_linux_sysvec, 1042 .interp_newpath = NULL, 1043 .brand_note = &linux_brandnote, 1044 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 1045}; 1046 1047static Elf32_Brandinfo linux_muslbrand = { 1048 .brand = ELFOSABI_LINUX, 1049 .machine = EM_386, 1050 .compat_3_brand = "Linux", 1051 .emul_path = "/compat/linux", 1052 .interp_path = "/lib/ld-musl-i386.so.1", 1053 .sysvec = &elf_linux_sysvec, 1054 .interp_newpath = NULL, 1055 .brand_note = &linux_brandnote, 1056 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 1057}; 1058 1059Elf32_Brandinfo *linux_brandlist[] = { 1060 &linux_brand, 1061 &linux_glibc2brand, 1062 &linux_muslbrand, 1063 NULL 1064}; 1065 1066static int 1067linux_elf_modevent(module_t mod, int type, void *data) 1068{ 1069 Elf32_Brandinfo **brandinfo; 1070 int error; 1071 struct linux_ioctl_handler **lihp; 1072 1073 error = 0; 1074 1075 switch(type) { 1076 case MOD_LOAD: 1077 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 1078 ++brandinfo) 1079 if (elf32_insert_brand_entry(*brandinfo) < 0) 1080 error = EINVAL; 1081 if (error == 0) { 1082 SET_FOREACH(lihp, linux_ioctl_handler_set) 1083 linux_ioctl_register_handler(*lihp); 1084 LIST_INIT(&futex_list); 1085 mtx_init(&futex_mtx, "ftllk", NULL, MTX_DEF); 1086 linux_exit_tag = EVENTHANDLER_REGISTER(process_exit, linux_proc_exit, 1087 NULL, 1000); 1088 linux_exec_tag = EVENTHANDLER_REGISTER(process_exec, linux_proc_exec, 1089 NULL, 1000); 1090 linux_thread_dtor_tag = EVENTHANDLER_REGISTER(thread_dtor, 1091 linux_thread_dtor, NULL, EVENTHANDLER_PRI_ANY); 1092 linux_get_machine(&linux_kplatform); 1093 linux_szplatform = roundup(strlen(linux_kplatform) + 1, 1094 sizeof(char *)); 1095 linux_osd_jail_register(); 1096 stclohz = (stathz ? stathz : hz); 1097 if (bootverbose) 1098 printf("Linux ELF exec handler installed\n"); 1099 } else 1100 printf("cannot insert Linux ELF brand handler\n"); 1101 break; 1102 case MOD_UNLOAD: 1103 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 1104 ++brandinfo) 1105 if (elf32_brand_inuse(*brandinfo)) 1106 error = EBUSY; 1107 if (error == 0) { 1108 for (brandinfo = &linux_brandlist[0]; 1109 *brandinfo != NULL; ++brandinfo) 1110 if (elf32_remove_brand_entry(*brandinfo) < 0) 1111 error = EINVAL; 1112 } 1113 if (error == 0) { 1114 SET_FOREACH(lihp, linux_ioctl_handler_set) 1115 linux_ioctl_unregister_handler(*lihp); 1116 mtx_destroy(&futex_mtx); 1117 EVENTHANDLER_DEREGISTER(process_exit, linux_exit_tag); 1118 EVENTHANDLER_DEREGISTER(process_exec, linux_exec_tag); 1119 EVENTHANDLER_DEREGISTER(thread_dtor, linux_thread_dtor_tag); 1120 linux_osd_jail_deregister(); 1121 if (bootverbose) 1122 printf("Linux ELF exec handler removed\n"); 1123 } else 1124 printf("Could not deinstall ELF interpreter entry\n"); 1125 break; 1126 default: 1127 return (EOPNOTSUPP); 1128 } 1129 return (error); 1130} 1131 1132static moduledata_t linux_elf_mod = { 1133 "linuxelf", 1134 linux_elf_modevent, 1135 0 1136}; 1137 1138DECLARE_MODULE_TIED(linuxelf, linux_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 1139FEATURE(linux, "Linux 32bit support"); 1140