1 /*- 2 * Copyright (c) 2013 Dmitry Chagin 3 * Copyright (c) 2004 Tim J. Robbins 4 * Copyright (c) 2003 Peter Wemm 5 * Copyright (c) 2002 Doug Rabson 6 * Copyright (c) 1998-1999 Andrew Gallatin 7 * Copyright (c) 1994-1996 Søren Schmidt 8 * All rights reserved. 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 * in this position and unchanged. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #define __ELF_WORD_SIZE 64 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/exec.h> 42 #include <sys/fcntl.h> 43 #include <sys/imgact.h> 44 #include <sys/imgact_elf.h> 45 #include <sys/kernel.h> 46 #include <sys/ktr.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/module.h> 50 #include <sys/mutex.h> 51 #include <sys/proc.h> 52 #include <sys/resourcevar.h> 53 #include <sys/signalvar.h> 54 #include <sys/syscallsubr.h> 55 #include <sys/sysctl.h> 56 #include <sys/sysent.h> 57 #include <sys/sysproto.h> 58 #include <sys/vnode.h> 59 #include <sys/eventhandler.h> 60 61 #include <vm/vm.h> 62 #include <vm/pmap.h> 63 #include <vm/vm_extern.h> 64 #include <vm/vm_map.h> 65 #include <vm/vm_object.h> 66 #include <vm/vm_page.h> 67 #include <vm/vm_param.h> 68 69 #include <machine/cpu.h> 70 #include <machine/md_var.h> 71 #include <machine/pcb.h> 72 #include <machine/specialreg.h> 73 #include <machine/trap.h> 74 75 #include <amd64/linux/linux.h> 76 #include <amd64/linux/linux_proto.h> 77 #include <compat/linux/linux_emul.h> 78 #include <compat/linux/linux_ioctl.h> 79 #include <compat/linux/linux_mib.h> 80 #include <compat/linux/linux_misc.h> 81 #include <compat/linux/linux_signal.h> 82 #include <compat/linux/linux_sysproto.h> 83 #include <compat/linux/linux_util.h> 84 #include <compat/linux/linux_vdso.h> 85 86 MODULE_VERSION(linux64, 1); 87 88 const char *linux_kplatform; 89 static int linux_szsigcode; 90 static vm_object_t linux_shared_page_obj; 91 static char *linux_shared_page_mapping; 92 extern char _binary_linux_locore_o_start; 93 extern char _binary_linux_locore_o_end; 94 95 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 96 97 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 98 99 static register_t * linux_copyout_strings(struct image_params *imgp); 100 static int linux_fixup_elf(register_t **stack_base, 101 struct image_params *iparams); 102 static bool linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 103 static void linux_vdso_install(void *param); 104 static void linux_vdso_deinstall(void *param); 105 static void linux_set_syscall_retval(struct thread *td, int error); 106 static int linux_fetch_syscall_args(struct thread *td); 107 static void linux_exec_setregs(struct thread *td, struct image_params *imgp, 108 u_long stack); 109 static int linux_vsyscall(struct thread *td); 110 111 #define LINUX_T_UNKNOWN 255 112 static int _bsd_to_linux_trapcode[] = { 113 LINUX_T_UNKNOWN, /* 0 */ 114 6, /* 1 T_PRIVINFLT */ 115 LINUX_T_UNKNOWN, /* 2 */ 116 3, /* 3 T_BPTFLT */ 117 LINUX_T_UNKNOWN, /* 4 */ 118 LINUX_T_UNKNOWN, /* 5 */ 119 16, /* 6 T_ARITHTRAP */ 120 254, /* 7 T_ASTFLT */ 121 LINUX_T_UNKNOWN, /* 8 */ 122 13, /* 9 T_PROTFLT */ 123 1, /* 10 T_TRCTRAP */ 124 LINUX_T_UNKNOWN, /* 11 */ 125 14, /* 12 T_PAGEFLT */ 126 LINUX_T_UNKNOWN, /* 13 */ 127 17, /* 14 T_ALIGNFLT */ 128 LINUX_T_UNKNOWN, /* 15 */ 129 LINUX_T_UNKNOWN, /* 16 */ 130 LINUX_T_UNKNOWN, /* 17 */ 131 0, /* 18 T_DIVIDE */ 132 2, /* 19 T_NMI */ 133 4, /* 20 T_OFLOW */ 134 5, /* 21 T_BOUND */ 135 7, /* 22 T_DNA */ 136 8, /* 23 T_DOUBLEFLT */ 137 9, /* 24 T_FPOPFLT */ 138 10, /* 25 T_TSSFLT */ 139 11, /* 26 T_SEGNPFLT */ 140 12, /* 27 T_STKFLT */ 141 18, /* 28 T_MCHK */ 142 19, /* 29 T_XMMFLT */ 143 15 /* 30 T_RESERVED */ 144 }; 145 #define bsd_to_linux_trapcode(code) \ 146 ((code)<nitems(_bsd_to_linux_trapcode)? \ 147 _bsd_to_linux_trapcode[(code)]: \ 148 LINUX_T_UNKNOWN) 149 150 LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 151 LINUX_VDSO_SYM_CHAR(linux_platform); 152 153 /* 154 * If FreeBSD & Linux have a difference of opinion about what a trap 155 * means, deal with it here. 156 * 157 * MPSAFE 158 */ 159 static int 160 linux_translate_traps(int signal, int trap_code) 161 { 162 163 if (signal != SIGBUS) 164 return (signal); 165 switch (trap_code) { 166 case T_PROTFLT: 167 case T_TSSFLT: 168 case T_DOUBLEFLT: 169 case T_PAGEFLT: 170 return (SIGSEGV); 171 default: 172 return (signal); 173 } 174 } 175 176 static int 177 linux_fetch_syscall_args(struct thread *td) 178 { 179 struct proc *p; 180 struct trapframe *frame; 181 struct syscall_args *sa; 182 183 p = td->td_proc; 184 frame = td->td_frame; 185 sa = &td->td_sa; 186 187 sa->args[0] = frame->tf_rdi; 188 sa->args[1] = frame->tf_rsi; 189 sa->args[2] = frame->tf_rdx; 190 sa->args[3] = frame->tf_rcx; 191 sa->args[4] = frame->tf_r8; 192 sa->args[5] = frame->tf_r9; 193 sa->code = frame->tf_rax; 194 195 if (sa->code >= p->p_sysent->sv_size) 196 /* nosys */ 197 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 198 else 199 sa->callp = &p->p_sysent->sv_table[sa->code]; 200 sa->narg = sa->callp->sy_narg; 201 202 td->td_retval[0] = 0; 203 return (0); 204 } 205 206 static void 207 linux_set_syscall_retval(struct thread *td, int error) 208 { 209 struct trapframe *frame = td->td_frame; 210 211 /* 212 * On Linux only %rcx and %r11 values are not preserved across 213 * the syscall. So, do not clobber %rdx and %r10. 214 */ 215 td->td_retval[1] = frame->tf_rdx; 216 if (error != EJUSTRETURN) 217 frame->tf_r10 = frame->tf_rcx; 218 219 cpu_set_syscall_retval(td, error); 220 221 /* Restore all registers. */ 222 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 223 } 224 225 static void 226 linux_copyout_auxargs(struct image_params *imgp, u_long *base) 227 { 228 Elf_Auxargs *args; 229 Elf_Auxinfo *argarray, *pos; 230 u_long auxlen; 231 struct proc *p; 232 int issetugid; 233 234 p = imgp->proc; 235 args = (Elf64_Auxargs *)imgp->auxargs; 236 argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP, 237 M_WAITOK | M_ZERO); 238 239 issetugid = p->p_flag & P_SUGID ? 1 : 0; 240 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 241 imgp->proc->p_sysent->sv_shared_page_base); 242 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 243 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 244 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 245 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 246 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 247 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 248 AUXARGS_ENTRY(pos, AT_BASE, args->base); 249 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 250 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 251 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 252 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 253 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 254 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 255 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 256 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 257 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 258 if (imgp->execpathp != 0) 259 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 260 if (args->execfd != -1) 261 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 262 AUXARGS_ENTRY(pos, AT_NULL, 0); 263 264 free(imgp->auxargs, M_TEMP); 265 imgp->auxargs = NULL; 266 KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs")); 267 268 auxlen = sizeof(*argarray) * (pos - argarray); 269 *base -= auxlen; 270 copyout(argarray, (void *)*base, auxlen); 271 free(argarray, M_TEMP); 272 } 273 274 static int 275 linux_fixup_elf(register_t **stack_base, struct image_params *imgp) 276 { 277 Elf_Addr *base; 278 279 base = (Elf64_Addr *)*stack_base; 280 base--; 281 if (suword(base, (uint64_t)imgp->args->argc) == -1) 282 return (EFAULT); 283 284 *stack_base = (register_t *)base; 285 return (0); 286 } 287 288 /* 289 * Copy strings out to the new process address space, constructing new arg 290 * and env vector tables. Return a pointer to the base so that it can be used 291 * as the initial stack pointer. 292 */ 293 static register_t * 294 linux_copyout_strings(struct image_params *imgp) 295 { 296 int argc, envc; 297 char **vectp; 298 char *stringp, *destp; 299 register_t *stack_base; 300 struct ps_strings *arginfo; 301 char canary[LINUX_AT_RANDOM_LEN]; 302 size_t execpath_len; 303 struct proc *p; 304 305 /* Calculate string base and vector table pointers. */ 306 if (imgp->execpath != NULL && imgp->auxargs != NULL) 307 execpath_len = strlen(imgp->execpath) + 1; 308 else 309 execpath_len = 0; 310 311 p = imgp->proc; 312 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 313 destp = (caddr_t)arginfo - SPARE_USRSPACE - 314 roundup(sizeof(canary), sizeof(char *)) - 315 roundup(execpath_len, sizeof(char *)) - 316 roundup(ARG_MAX - imgp->args->stringspace, sizeof(char *)); 317 318 if (execpath_len != 0) { 319 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 320 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 321 } 322 323 /* Prepare the canary for SSP. */ 324 arc4rand(canary, sizeof(canary), 0); 325 imgp->canary = (uintptr_t)arginfo - 326 roundup(execpath_len, sizeof(char *)) - 327 roundup(sizeof(canary), sizeof(char *)); 328 copyout(canary, (void *)imgp->canary, sizeof(canary)); 329 330 vectp = (char **)destp; 331 332 /* 333 * Starting with 2.24, glibc depends on a 16-byte stack alignment. 334 * One "long argc" will be prepended later. 335 */ 336 vectp = (char **)((((uintptr_t)vectp + 8) & ~0xF) - 8); 337 338 if (imgp->auxargs) 339 imgp->sysent->sv_copyout_auxargs(imgp, (u_long *)&vectp); 340 341 /* 342 * Allocate room for the argv[] and env vectors including the 343 * terminating NULL pointers. 344 */ 345 vectp -= imgp->args->argc + 1 + imgp->args->envc + 1; 346 347 /* vectp also becomes our initial stack base. */ 348 stack_base = (register_t *)vectp; 349 350 stringp = imgp->args->begin_argv; 351 argc = imgp->args->argc; 352 envc = imgp->args->envc; 353 354 /* Copy out strings - arguments and environment. */ 355 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 356 357 /* Fill in "ps_strings" struct for ps, w, etc. */ 358 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 359 suword(&arginfo->ps_nargvstr, argc); 360 361 /* Fill in argument portion of vector table. */ 362 for (; argc > 0; --argc) { 363 suword(vectp++, (long)(intptr_t)destp); 364 while (*stringp++ != 0) 365 destp++; 366 destp++; 367 } 368 369 /* A null vector table pointer separates the argp's from the envp's. */ 370 suword(vectp++, 0); 371 372 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 373 suword(&arginfo->ps_nenvstr, envc); 374 375 /* Fill in environment portion of vector table. */ 376 for (; envc > 0; --envc) { 377 suword(vectp++, (long)(intptr_t)destp); 378 while (*stringp++ != 0) 379 destp++; 380 destp++; 381 } 382 383 /* The end of the vector table is a null pointer. */ 384 suword(vectp, 0); 385 return (stack_base); 386 } 387 388 /* 389 * Reset registers to default values on exec. 390 */ 391 static void 392 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 393 { 394 struct trapframe *regs; 395 struct pcb *pcb; 396 register_t saved_rflags; 397 398 regs = td->td_frame; 399 pcb = td->td_pcb; 400 401 if (td->td_proc->p_md.md_ldt != NULL) 402 user_ldt_free(td); 403 404 pcb->pcb_fsbase = 0; 405 pcb->pcb_gsbase = 0; 406 clear_pcb_flags(pcb, PCB_32BIT); 407 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 408 set_pcb_flags(pcb, PCB_FULL_IRET); 409 410 saved_rflags = regs->tf_rflags & PSL_T; 411 bzero((char *)regs, sizeof(struct trapframe)); 412 regs->tf_rip = imgp->entry_addr; 413 regs->tf_rsp = stack; 414 regs->tf_rflags = PSL_USER | saved_rflags; 415 regs->tf_ss = _udatasel; 416 regs->tf_cs = _ucodesel; 417 regs->tf_ds = _udatasel; 418 regs->tf_es = _udatasel; 419 regs->tf_fs = _ufssel; 420 regs->tf_gs = _ugssel; 421 regs->tf_flags = TF_HASSEGS; 422 423 /* 424 * Reset the hardware debug registers if they were in use. 425 * They won't have any meaning for the newly exec'd process. 426 */ 427 if (pcb->pcb_flags & PCB_DBREGS) { 428 pcb->pcb_dr0 = 0; 429 pcb->pcb_dr1 = 0; 430 pcb->pcb_dr2 = 0; 431 pcb->pcb_dr3 = 0; 432 pcb->pcb_dr6 = 0; 433 pcb->pcb_dr7 = 0; 434 if (pcb == curpcb) { 435 /* 436 * Clear the debug registers on the running 437 * CPU, otherwise they will end up affecting 438 * the next process we switch to. 439 */ 440 reset_dbregs(); 441 } 442 clear_pcb_flags(pcb, PCB_DBREGS); 443 } 444 445 /* 446 * Drop the FP state if we hold it, so that the process gets a 447 * clean FP state if it uses the FPU again. 448 */ 449 fpstate_drop(td); 450 } 451 452 /* 453 * Copied from amd64/amd64/machdep.c 454 * 455 * XXX fpu state need? don't think so 456 */ 457 int 458 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 459 { 460 struct proc *p; 461 struct l_ucontext uc; 462 struct l_sigcontext *context; 463 struct trapframe *regs; 464 unsigned long rflags; 465 int error; 466 ksiginfo_t ksi; 467 468 regs = td->td_frame; 469 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 470 if (error != 0) 471 return (error); 472 473 p = td->td_proc; 474 context = &uc.uc_mcontext; 475 rflags = context->sc_rflags; 476 477 /* 478 * Don't allow users to change privileged or reserved flags. 479 */ 480 /* 481 * XXX do allow users to change the privileged flag PSL_RF. 482 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 483 * should sometimes set it there too. tf_rflags is kept in 484 * the signal context during signal handling and there is no 485 * other place to remember it, so the PSL_RF bit may be 486 * corrupted by the signal handler without us knowing. 487 * Corruption of the PSL_RF bit at worst causes one more or 488 * one less debugger trap, so allowing it is fairly harmless. 489 */ 490 491 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 492 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 493 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 494 return (EINVAL); 495 } 496 497 /* 498 * Don't allow users to load a valid privileged %cs. Let the 499 * hardware check for invalid selectors, excess privilege in 500 * other selectors, invalid %eip's and invalid %esp's. 501 */ 502 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 503 if (!CS_SECURE(context->sc_cs)) { 504 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 505 ksiginfo_init_trap(&ksi); 506 ksi.ksi_signo = SIGBUS; 507 ksi.ksi_code = BUS_OBJERR; 508 ksi.ksi_trapno = T_PROTFLT; 509 ksi.ksi_addr = (void *)regs->tf_rip; 510 trapsignal(td, &ksi); 511 return (EINVAL); 512 } 513 514 PROC_LOCK(p); 515 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 516 SIG_CANTMASK(td->td_sigmask); 517 signotify(td); 518 PROC_UNLOCK(p); 519 520 regs->tf_rdi = context->sc_rdi; 521 regs->tf_rsi = context->sc_rsi; 522 regs->tf_rdx = context->sc_rdx; 523 regs->tf_rbp = context->sc_rbp; 524 regs->tf_rbx = context->sc_rbx; 525 regs->tf_rcx = context->sc_rcx; 526 regs->tf_rax = context->sc_rax; 527 regs->tf_rip = context->sc_rip; 528 regs->tf_rsp = context->sc_rsp; 529 regs->tf_r8 = context->sc_r8; 530 regs->tf_r9 = context->sc_r9; 531 regs->tf_r10 = context->sc_r10; 532 regs->tf_r11 = context->sc_r11; 533 regs->tf_r12 = context->sc_r12; 534 regs->tf_r13 = context->sc_r13; 535 regs->tf_r14 = context->sc_r14; 536 regs->tf_r15 = context->sc_r15; 537 regs->tf_cs = context->sc_cs; 538 regs->tf_err = context->sc_err; 539 regs->tf_rflags = rflags; 540 541 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 542 return (EJUSTRETURN); 543 } 544 545 /* 546 * copied from amd64/amd64/machdep.c 547 * 548 * Send an interrupt to process. 549 */ 550 static void 551 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 552 { 553 struct l_rt_sigframe sf, *sfp; 554 struct proc *p; 555 struct thread *td; 556 struct sigacts *psp; 557 caddr_t sp; 558 struct trapframe *regs; 559 int sig, code; 560 int oonstack; 561 562 td = curthread; 563 p = td->td_proc; 564 PROC_LOCK_ASSERT(p, MA_OWNED); 565 sig = ksi->ksi_signo; 566 psp = p->p_sigacts; 567 code = ksi->ksi_code; 568 mtx_assert(&psp->ps_mtx, MA_OWNED); 569 regs = td->td_frame; 570 oonstack = sigonstack(regs->tf_rsp); 571 572 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 573 catcher, sig, mask, code); 574 575 /* Allocate space for the signal handler context. */ 576 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 577 SIGISMEMBER(psp->ps_sigonstack, sig)) { 578 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 579 sizeof(struct l_rt_sigframe); 580 } else 581 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 582 /* Align to 16 bytes. */ 583 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 584 mtx_unlock(&psp->ps_mtx); 585 586 /* Translate the signal. */ 587 sig = bsd_to_linux_signal(sig); 588 589 /* Save user context. */ 590 bzero(&sf, sizeof(sf)); 591 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 592 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 593 594 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 595 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 596 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 597 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 598 PROC_UNLOCK(p); 599 600 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 601 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 602 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 603 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 604 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 605 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 606 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 607 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 608 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 609 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 610 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 611 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 612 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 613 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 614 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 615 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 616 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 617 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 618 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 619 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 620 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 621 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 622 623 /* Build the argument list for the signal handler. */ 624 regs->tf_rdi = sig; /* arg 1 in %rdi */ 625 regs->tf_rax = 0; 626 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 627 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 628 629 sf.sf_handler = catcher; 630 /* Fill in POSIX parts. */ 631 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 632 633 /* Copy the sigframe out to the user's stack. */ 634 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 635 PROC_LOCK(p); 636 sigexit(td, SIGILL); 637 } 638 639 regs->tf_rsp = (long)sfp; 640 regs->tf_rip = linux_rt_sigcode; 641 regs->tf_rflags &= ~(PSL_T | PSL_D); 642 regs->tf_cs = _ucodesel; 643 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 644 PROC_LOCK(p); 645 mtx_lock(&psp->ps_mtx); 646 } 647 648 #define LINUX_VSYSCALL_START (-10UL << 20) 649 #define LINUX_VSYSCALL_SZ 1024 650 651 const unsigned long linux_vsyscall_vector[] = { 652 LINUX_SYS_gettimeofday, 653 LINUX_SYS_linux_time, 654 /* getcpu not implemented */ 655 }; 656 657 static int 658 linux_vsyscall(struct thread *td) 659 { 660 struct trapframe *frame; 661 uint64_t retqaddr; 662 int code, traced; 663 int error; 664 665 frame = td->td_frame; 666 667 /* Check %rip for vsyscall area. */ 668 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 669 return (EINVAL); 670 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 671 return (EINVAL); 672 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 673 if (code >= nitems(linux_vsyscall_vector)) 674 return (EINVAL); 675 676 /* 677 * vsyscall called as callq *(%rax), so we must 678 * use return address from %rsp and also fixup %rsp. 679 */ 680 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 681 if (error) 682 return (error); 683 684 frame->tf_rip = retqaddr; 685 frame->tf_rax = linux_vsyscall_vector[code]; 686 frame->tf_rsp += 8; 687 688 traced = (frame->tf_flags & PSL_T); 689 690 amd64_syscall(td, traced); 691 692 return (0); 693 } 694 695 struct sysentvec elf_linux_sysvec = { 696 .sv_size = LINUX_SYS_MAXSYSCALL, 697 .sv_table = linux_sysent, 698 .sv_errsize = ELAST + 1, 699 .sv_errtbl = linux_errtbl, 700 .sv_transtrap = linux_translate_traps, 701 .sv_fixup = linux_fixup_elf, 702 .sv_sendsig = linux_rt_sendsig, 703 .sv_sigcode = &_binary_linux_locore_o_start, 704 .sv_szsigcode = &linux_szsigcode, 705 .sv_name = "Linux ELF64", 706 .sv_coredump = elf64_coredump, 707 .sv_imgact_try = linux_exec_imgact_try, 708 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 709 .sv_minuser = VM_MIN_ADDRESS, 710 .sv_maxuser = VM_MAXUSER_ADDRESS, 711 .sv_usrstack = USRSTACK, 712 .sv_psstrings = PS_STRINGS, 713 .sv_stackprot = VM_PROT_ALL, 714 .sv_copyout_auxargs = linux_copyout_auxargs, 715 .sv_copyout_strings = linux_copyout_strings, 716 .sv_setregs = linux_exec_setregs, 717 .sv_fixlimit = NULL, 718 .sv_maxssiz = NULL, 719 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 720 .sv_set_syscall_retval = linux_set_syscall_retval, 721 .sv_fetch_syscall_args = linux_fetch_syscall_args, 722 .sv_syscallnames = NULL, 723 .sv_shared_page_base = SHAREDPAGE, 724 .sv_shared_page_len = PAGE_SIZE, 725 .sv_schedtail = linux_schedtail, 726 .sv_thread_detach = linux_thread_detach, 727 .sv_trap = linux_vsyscall, 728 }; 729 730 static void 731 linux_vdso_install(void *param) 732 { 733 734 amd64_lower_shared_page(&elf_linux_sysvec); 735 736 linux_szsigcode = (&_binary_linux_locore_o_end - 737 &_binary_linux_locore_o_start); 738 739 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 740 panic("Linux invalid vdso size\n"); 741 742 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 743 744 linux_shared_page_obj = __elfN(linux_shared_page_init) 745 (&linux_shared_page_mapping); 746 747 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 748 749 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 750 linux_szsigcode); 751 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 752 753 linux_kplatform = linux_shared_page_mapping + 754 (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base); 755 } 756 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 757 linux_vdso_install, NULL); 758 759 static void 760 linux_vdso_deinstall(void *param) 761 { 762 763 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 764 } 765 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 766 linux_vdso_deinstall, NULL); 767 768 static char GNULINUX_ABI_VENDOR[] = "GNU"; 769 static int GNULINUX_ABI_DESC = 0; 770 771 static bool 772 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 773 { 774 const Elf32_Word *desc; 775 uintptr_t p; 776 777 p = (uintptr_t)(note + 1); 778 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 779 780 desc = (const Elf32_Word *)p; 781 if (desc[0] != GNULINUX_ABI_DESC) 782 return (false); 783 784 /* 785 * For Linux we encode osrel using the Linux convention of 786 * (version << 16) | (major << 8) | (minor) 787 * See macro in linux_mib.h 788 */ 789 *osrel = LINUX_KERNVER(desc[1], desc[2], desc[3]); 790 791 return (true); 792 } 793 794 static Elf_Brandnote linux64_brandnote = { 795 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 796 .hdr.n_descsz = 16, 797 .hdr.n_type = 1, 798 .vendor = GNULINUX_ABI_VENDOR, 799 .flags = BN_TRANSLATE_OSREL, 800 .trans_osrel = linux_trans_osrel 801 }; 802 803 static Elf64_Brandinfo linux_glibc2brand = { 804 .brand = ELFOSABI_LINUX, 805 .machine = EM_X86_64, 806 .compat_3_brand = "Linux", 807 .emul_path = "/compat/linux", 808 .interp_path = "/lib64/ld-linux-x86-64.so.2", 809 .sysvec = &elf_linux_sysvec, 810 .interp_newpath = NULL, 811 .brand_note = &linux64_brandnote, 812 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 813 }; 814 815 static Elf64_Brandinfo linux_glibc2brandshort = { 816 .brand = ELFOSABI_LINUX, 817 .machine = EM_X86_64, 818 .compat_3_brand = "Linux", 819 .emul_path = "/compat/linux", 820 .interp_path = "/lib64/ld-linux.so.2", 821 .sysvec = &elf_linux_sysvec, 822 .interp_newpath = NULL, 823 .brand_note = &linux64_brandnote, 824 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 825 }; 826 827 static Elf64_Brandinfo linux_muslbrand = { 828 .brand = ELFOSABI_LINUX, 829 .machine = EM_X86_64, 830 .compat_3_brand = "Linux", 831 .emul_path = "/compat/linux", 832 .interp_path = "/lib/ld-musl-x86_64.so.1", 833 .sysvec = &elf_linux_sysvec, 834 .interp_newpath = NULL, 835 .brand_note = &linux64_brandnote, 836 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 837 }; 838 839 Elf64_Brandinfo *linux_brandlist[] = { 840 &linux_glibc2brand, 841 &linux_glibc2brandshort, 842 &linux_muslbrand, 843 NULL 844 }; 845 846 static int 847 linux64_elf_modevent(module_t mod, int type, void *data) 848 { 849 Elf64_Brandinfo **brandinfo; 850 int error; 851 struct linux_ioctl_handler **lihp; 852 853 error = 0; 854 855 switch(type) { 856 case MOD_LOAD: 857 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 858 ++brandinfo) 859 if (elf64_insert_brand_entry(*brandinfo) < 0) 860 error = EINVAL; 861 if (error == 0) { 862 SET_FOREACH(lihp, linux_ioctl_handler_set) 863 linux_ioctl_register_handler(*lihp); 864 stclohz = (stathz ? stathz : hz); 865 if (bootverbose) 866 printf("Linux x86-64 ELF exec handler installed\n"); 867 } else 868 printf("cannot insert Linux x86-64 ELF brand handler\n"); 869 break; 870 case MOD_UNLOAD: 871 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 872 ++brandinfo) 873 if (elf64_brand_inuse(*brandinfo)) 874 error = EBUSY; 875 if (error == 0) { 876 for (brandinfo = &linux_brandlist[0]; 877 *brandinfo != NULL; ++brandinfo) 878 if (elf64_remove_brand_entry(*brandinfo) < 0) 879 error = EINVAL; 880 } 881 if (error == 0) { 882 SET_FOREACH(lihp, linux_ioctl_handler_set) 883 linux_ioctl_unregister_handler(*lihp); 884 if (bootverbose) 885 printf("Linux ELF exec handler removed\n"); 886 } else 887 printf("Could not deinstall ELF interpreter entry\n"); 888 break; 889 default: 890 return (EOPNOTSUPP); 891 } 892 return (error); 893 } 894 895 static moduledata_t linux64_elf_mod = { 896 "linux64elf", 897 linux64_elf_modevent, 898 0 899 }; 900 901 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 902 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 903 FEATURE(linux64, "Linux 64bit support"); 904