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 int 226 linux_fixup_elf(register_t **stack_base, struct image_params *imgp) 227 { 228 Elf_Auxargs *args; 229 Elf_Auxinfo *argarray, *pos; 230 Elf_Addr *auxbase, *base; 231 struct ps_strings *arginfo; 232 struct proc *p; 233 int error, issetugid; 234 235 p = imgp->proc; 236 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 237 238 KASSERT(curthread->td_proc == imgp->proc, 239 ("unsafe linux_fixup_elf(), should be curproc")); 240 base = (Elf64_Addr *)*stack_base; 241 args = (Elf64_Auxargs *)imgp->auxargs; 242 auxbase = base + imgp->args->argc + 1 + imgp->args->envc + 1; 243 argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP, 244 M_WAITOK | M_ZERO); 245 246 issetugid = p->p_flag & P_SUGID ? 1 : 0; 247 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 248 imgp->proc->p_sysent->sv_shared_page_base); 249 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 250 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 251 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 252 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 253 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 254 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 255 AUXARGS_ENTRY(pos, AT_BASE, args->base); 256 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 257 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 258 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 259 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 260 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 261 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 262 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 263 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 264 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 265 if (imgp->execpathp != 0) 266 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 267 if (args->execfd != -1) 268 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 269 AUXARGS_ENTRY(pos, AT_NULL, 0); 270 free(imgp->auxargs, M_TEMP); 271 imgp->auxargs = NULL; 272 KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs")); 273 274 error = copyout(argarray, auxbase, sizeof(*argarray) * LINUX_AT_COUNT); 275 free(argarray, M_TEMP); 276 if (error != 0) 277 return (error); 278 279 base--; 280 if (suword(base, (uint64_t)imgp->args->argc) == -1) 281 return (EFAULT); 282 283 *stack_base = (register_t *)base; 284 return (0); 285 } 286 287 /* 288 * Copy strings out to the new process address space, constructing new arg 289 * and env vector tables. Return a pointer to the base so that it can be used 290 * as the initial stack pointer. 291 */ 292 static register_t * 293 linux_copyout_strings(struct image_params *imgp) 294 { 295 int argc, envc; 296 char **vectp; 297 char *stringp, *destp; 298 register_t *stack_base; 299 struct ps_strings *arginfo; 300 char canary[LINUX_AT_RANDOM_LEN]; 301 size_t execpath_len; 302 struct proc *p; 303 304 /* Calculate string base and vector table pointers. */ 305 if (imgp->execpath != NULL && imgp->auxargs != NULL) 306 execpath_len = strlen(imgp->execpath) + 1; 307 else 308 execpath_len = 0; 309 310 p = imgp->proc; 311 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 312 destp = (caddr_t)arginfo - SPARE_USRSPACE - 313 roundup(sizeof(canary), sizeof(char *)) - 314 roundup(execpath_len, sizeof(char *)) - 315 roundup(ARG_MAX - imgp->args->stringspace, sizeof(char *)); 316 317 if (execpath_len != 0) { 318 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 319 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 320 } 321 322 /* Prepare the canary for SSP. */ 323 arc4rand(canary, sizeof(canary), 0); 324 imgp->canary = (uintptr_t)arginfo - 325 roundup(execpath_len, sizeof(char *)) - 326 roundup(sizeof(canary), sizeof(char *)); 327 copyout(canary, (void *)imgp->canary, sizeof(canary)); 328 329 vectp = (char **)destp; 330 if (imgp->auxargs) { 331 /* 332 * Allocate room on the stack for the ELF auxargs 333 * array. It has LINUX_AT_COUNT entries. 334 */ 335 vectp -= howmany(LINUX_AT_COUNT * sizeof(Elf64_Auxinfo), 336 sizeof(*vectp)); 337 } 338 339 /* 340 * Allocate room for the argv[] and env vectors including the 341 * terminating NULL pointers. 342 */ 343 vectp -= imgp->args->argc + 1 + imgp->args->envc + 1; 344 345 /* 346 * Starting with 2.24, glibc depends on a 16-byte stack alignment. 347 * One "long argc" will be prepended later. 348 */ 349 vectp = (char **)((((uintptr_t)vectp + 8) & ~0xF) - 8); 350 351 /* vectp also becomes our initial stack base. */ 352 stack_base = (register_t *)vectp; 353 354 stringp = imgp->args->begin_argv; 355 argc = imgp->args->argc; 356 envc = imgp->args->envc; 357 358 /* Copy out strings - arguments and environment. */ 359 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 360 361 /* Fill in "ps_strings" struct for ps, w, etc. */ 362 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 363 suword(&arginfo->ps_nargvstr, argc); 364 365 /* Fill in argument portion of vector table. */ 366 for (; argc > 0; --argc) { 367 suword(vectp++, (long)(intptr_t)destp); 368 while (*stringp++ != 0) 369 destp++; 370 destp++; 371 } 372 373 /* A null vector table pointer separates the argp's from the envp's. */ 374 suword(vectp++, 0); 375 376 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 377 suword(&arginfo->ps_nenvstr, envc); 378 379 /* Fill in environment portion of vector table. */ 380 for (; envc > 0; --envc) { 381 suword(vectp++, (long)(intptr_t)destp); 382 while (*stringp++ != 0) 383 destp++; 384 destp++; 385 } 386 387 /* The end of the vector table is a null pointer. */ 388 suword(vectp, 0); 389 return (stack_base); 390 } 391 392 /* 393 * Reset registers to default values on exec. 394 */ 395 static void 396 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 397 { 398 struct trapframe *regs; 399 struct pcb *pcb; 400 register_t saved_rflags; 401 402 regs = td->td_frame; 403 pcb = td->td_pcb; 404 405 if (td->td_proc->p_md.md_ldt != NULL) 406 user_ldt_free(td); 407 408 pcb->pcb_fsbase = 0; 409 pcb->pcb_gsbase = 0; 410 clear_pcb_flags(pcb, PCB_32BIT); 411 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 412 set_pcb_flags(pcb, PCB_FULL_IRET); 413 414 saved_rflags = regs->tf_rflags & PSL_T; 415 bzero((char *)regs, sizeof(struct trapframe)); 416 regs->tf_rip = imgp->entry_addr; 417 regs->tf_rsp = stack; 418 regs->tf_rflags = PSL_USER | saved_rflags; 419 regs->tf_ss = _udatasel; 420 regs->tf_cs = _ucodesel; 421 regs->tf_ds = _udatasel; 422 regs->tf_es = _udatasel; 423 regs->tf_fs = _ufssel; 424 regs->tf_gs = _ugssel; 425 regs->tf_flags = TF_HASSEGS; 426 427 /* 428 * Reset the hardware debug registers if they were in use. 429 * They won't have any meaning for the newly exec'd process. 430 */ 431 if (pcb->pcb_flags & PCB_DBREGS) { 432 pcb->pcb_dr0 = 0; 433 pcb->pcb_dr1 = 0; 434 pcb->pcb_dr2 = 0; 435 pcb->pcb_dr3 = 0; 436 pcb->pcb_dr6 = 0; 437 pcb->pcb_dr7 = 0; 438 if (pcb == curpcb) { 439 /* 440 * Clear the debug registers on the running 441 * CPU, otherwise they will end up affecting 442 * the next process we switch to. 443 */ 444 reset_dbregs(); 445 } 446 clear_pcb_flags(pcb, PCB_DBREGS); 447 } 448 449 /* 450 * Drop the FP state if we hold it, so that the process gets a 451 * clean FP state if it uses the FPU again. 452 */ 453 fpstate_drop(td); 454 } 455 456 /* 457 * Copied from amd64/amd64/machdep.c 458 * 459 * XXX fpu state need? don't think so 460 */ 461 int 462 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 463 { 464 struct proc *p; 465 struct l_ucontext uc; 466 struct l_sigcontext *context; 467 struct trapframe *regs; 468 unsigned long rflags; 469 int error; 470 ksiginfo_t ksi; 471 472 regs = td->td_frame; 473 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 474 if (error != 0) 475 return (error); 476 477 p = td->td_proc; 478 context = &uc.uc_mcontext; 479 rflags = context->sc_rflags; 480 481 /* 482 * Don't allow users to change privileged or reserved flags. 483 */ 484 /* 485 * XXX do allow users to change the privileged flag PSL_RF. 486 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 487 * should sometimes set it there too. tf_rflags is kept in 488 * the signal context during signal handling and there is no 489 * other place to remember it, so the PSL_RF bit may be 490 * corrupted by the signal handler without us knowing. 491 * Corruption of the PSL_RF bit at worst causes one more or 492 * one less debugger trap, so allowing it is fairly harmless. 493 */ 494 495 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 496 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 497 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 498 return (EINVAL); 499 } 500 501 /* 502 * Don't allow users to load a valid privileged %cs. Let the 503 * hardware check for invalid selectors, excess privilege in 504 * other selectors, invalid %eip's and invalid %esp's. 505 */ 506 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 507 if (!CS_SECURE(context->sc_cs)) { 508 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 509 ksiginfo_init_trap(&ksi); 510 ksi.ksi_signo = SIGBUS; 511 ksi.ksi_code = BUS_OBJERR; 512 ksi.ksi_trapno = T_PROTFLT; 513 ksi.ksi_addr = (void *)regs->tf_rip; 514 trapsignal(td, &ksi); 515 return (EINVAL); 516 } 517 518 PROC_LOCK(p); 519 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 520 SIG_CANTMASK(td->td_sigmask); 521 signotify(td); 522 PROC_UNLOCK(p); 523 524 regs->tf_rdi = context->sc_rdi; 525 regs->tf_rsi = context->sc_rsi; 526 regs->tf_rdx = context->sc_rdx; 527 regs->tf_rbp = context->sc_rbp; 528 regs->tf_rbx = context->sc_rbx; 529 regs->tf_rcx = context->sc_rcx; 530 regs->tf_rax = context->sc_rax; 531 regs->tf_rip = context->sc_rip; 532 regs->tf_rsp = context->sc_rsp; 533 regs->tf_r8 = context->sc_r8; 534 regs->tf_r9 = context->sc_r9; 535 regs->tf_r10 = context->sc_r10; 536 regs->tf_r11 = context->sc_r11; 537 regs->tf_r12 = context->sc_r12; 538 regs->tf_r13 = context->sc_r13; 539 regs->tf_r14 = context->sc_r14; 540 regs->tf_r15 = context->sc_r15; 541 regs->tf_cs = context->sc_cs; 542 regs->tf_err = context->sc_err; 543 regs->tf_rflags = rflags; 544 545 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 546 return (EJUSTRETURN); 547 } 548 549 /* 550 * copied from amd64/amd64/machdep.c 551 * 552 * Send an interrupt to process. 553 */ 554 static void 555 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 556 { 557 struct l_rt_sigframe sf, *sfp; 558 struct proc *p; 559 struct thread *td; 560 struct sigacts *psp; 561 caddr_t sp; 562 struct trapframe *regs; 563 int sig, code; 564 int oonstack; 565 566 td = curthread; 567 p = td->td_proc; 568 PROC_LOCK_ASSERT(p, MA_OWNED); 569 sig = ksi->ksi_signo; 570 psp = p->p_sigacts; 571 code = ksi->ksi_code; 572 mtx_assert(&psp->ps_mtx, MA_OWNED); 573 regs = td->td_frame; 574 oonstack = sigonstack(regs->tf_rsp); 575 576 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 577 catcher, sig, mask, code); 578 579 /* Allocate space for the signal handler context. */ 580 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 581 SIGISMEMBER(psp->ps_sigonstack, sig)) { 582 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 583 sizeof(struct l_rt_sigframe); 584 } else 585 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 586 /* Align to 16 bytes. */ 587 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 588 mtx_unlock(&psp->ps_mtx); 589 590 /* Translate the signal. */ 591 sig = bsd_to_linux_signal(sig); 592 593 /* Save user context. */ 594 bzero(&sf, sizeof(sf)); 595 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 596 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 597 598 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 599 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 600 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 601 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 602 PROC_UNLOCK(p); 603 604 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 605 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 606 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 607 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 608 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 609 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 610 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 611 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 612 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 613 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 614 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 615 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 616 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 617 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 618 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 619 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 620 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 621 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 622 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 623 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 624 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 625 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 626 627 /* Build the argument list for the signal handler. */ 628 regs->tf_rdi = sig; /* arg 1 in %rdi */ 629 regs->tf_rax = 0; 630 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 631 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 632 633 sf.sf_handler = catcher; 634 /* Fill in POSIX parts. */ 635 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 636 637 /* Copy the sigframe out to the user's stack. */ 638 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 639 PROC_LOCK(p); 640 sigexit(td, SIGILL); 641 } 642 643 regs->tf_rsp = (long)sfp; 644 regs->tf_rip = linux_rt_sigcode; 645 regs->tf_rflags &= ~(PSL_T | PSL_D); 646 regs->tf_cs = _ucodesel; 647 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 648 PROC_LOCK(p); 649 mtx_lock(&psp->ps_mtx); 650 } 651 652 #define LINUX_VSYSCALL_START (-10UL << 20) 653 #define LINUX_VSYSCALL_SZ 1024 654 655 const unsigned long linux_vsyscall_vector[] = { 656 LINUX_SYS_gettimeofday, 657 LINUX_SYS_linux_time, 658 /* getcpu not implemented */ 659 }; 660 661 static int 662 linux_vsyscall(struct thread *td) 663 { 664 struct trapframe *frame; 665 uint64_t retqaddr; 666 int code, traced; 667 int error; 668 669 frame = td->td_frame; 670 671 /* Check %rip for vsyscall area. */ 672 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 673 return (EINVAL); 674 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 675 return (EINVAL); 676 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 677 if (code >= nitems(linux_vsyscall_vector)) 678 return (EINVAL); 679 680 /* 681 * vsyscall called as callq *(%rax), so we must 682 * use return address from %rsp and also fixup %rsp. 683 */ 684 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 685 if (error) 686 return (error); 687 688 frame->tf_rip = retqaddr; 689 frame->tf_rax = linux_vsyscall_vector[code]; 690 frame->tf_rsp += 8; 691 692 traced = (frame->tf_flags & PSL_T); 693 694 amd64_syscall(td, traced); 695 696 return (0); 697 } 698 699 struct sysentvec elf_linux_sysvec = { 700 .sv_size = LINUX_SYS_MAXSYSCALL, 701 .sv_table = linux_sysent, 702 .sv_errsize = ELAST + 1, 703 .sv_errtbl = linux_errtbl, 704 .sv_transtrap = linux_translate_traps, 705 .sv_fixup = linux_fixup_elf, 706 .sv_sendsig = linux_rt_sendsig, 707 .sv_sigcode = &_binary_linux_locore_o_start, 708 .sv_szsigcode = &linux_szsigcode, 709 .sv_name = "Linux ELF64", 710 .sv_coredump = elf64_coredump, 711 .sv_imgact_try = linux_exec_imgact_try, 712 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 713 .sv_minuser = VM_MIN_ADDRESS, 714 .sv_maxuser = VM_MAXUSER_ADDRESS, 715 .sv_usrstack = USRSTACK, 716 .sv_psstrings = PS_STRINGS, 717 .sv_stackprot = VM_PROT_ALL, 718 .sv_copyout_strings = linux_copyout_strings, 719 .sv_setregs = linux_exec_setregs, 720 .sv_fixlimit = NULL, 721 .sv_maxssiz = NULL, 722 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 723 .sv_set_syscall_retval = linux_set_syscall_retval, 724 .sv_fetch_syscall_args = linux_fetch_syscall_args, 725 .sv_syscallnames = NULL, 726 .sv_shared_page_base = SHAREDPAGE, 727 .sv_shared_page_len = PAGE_SIZE, 728 .sv_schedtail = linux_schedtail, 729 .sv_thread_detach = linux_thread_detach, 730 .sv_trap = linux_vsyscall, 731 }; 732 733 static void 734 linux_vdso_install(void *param) 735 { 736 737 amd64_lower_shared_page(&elf_linux_sysvec); 738 739 linux_szsigcode = (&_binary_linux_locore_o_end - 740 &_binary_linux_locore_o_start); 741 742 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 743 panic("Linux invalid vdso size\n"); 744 745 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 746 747 linux_shared_page_obj = __elfN(linux_shared_page_init) 748 (&linux_shared_page_mapping); 749 750 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 751 752 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 753 linux_szsigcode); 754 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 755 756 linux_kplatform = linux_shared_page_mapping + 757 (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base); 758 } 759 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 760 linux_vdso_install, NULL); 761 762 static void 763 linux_vdso_deinstall(void *param) 764 { 765 766 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 767 } 768 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 769 linux_vdso_deinstall, NULL); 770 771 static char GNULINUX_ABI_VENDOR[] = "GNU"; 772 static int GNULINUX_ABI_DESC = 0; 773 774 static bool 775 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 776 { 777 const Elf32_Word *desc; 778 uintptr_t p; 779 780 p = (uintptr_t)(note + 1); 781 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 782 783 desc = (const Elf32_Word *)p; 784 if (desc[0] != GNULINUX_ABI_DESC) 785 return (false); 786 787 /* 788 * For Linux we encode osrel using the Linux convention of 789 * (version << 16) | (major << 8) | (minor) 790 * See macro in linux_mib.h 791 */ 792 *osrel = LINUX_KERNVER(desc[1], desc[2], desc[3]); 793 794 return (true); 795 } 796 797 static Elf_Brandnote linux64_brandnote = { 798 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 799 .hdr.n_descsz = 16, 800 .hdr.n_type = 1, 801 .vendor = GNULINUX_ABI_VENDOR, 802 .flags = BN_TRANSLATE_OSREL, 803 .trans_osrel = linux_trans_osrel 804 }; 805 806 static Elf64_Brandinfo linux_glibc2brand = { 807 .brand = ELFOSABI_LINUX, 808 .machine = EM_X86_64, 809 .compat_3_brand = "Linux", 810 .emul_path = "/compat/linux", 811 .interp_path = "/lib64/ld-linux-x86-64.so.2", 812 .sysvec = &elf_linux_sysvec, 813 .interp_newpath = NULL, 814 .brand_note = &linux64_brandnote, 815 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 816 }; 817 818 static Elf64_Brandinfo linux_glibc2brandshort = { 819 .brand = ELFOSABI_LINUX, 820 .machine = EM_X86_64, 821 .compat_3_brand = "Linux", 822 .emul_path = "/compat/linux", 823 .interp_path = "/lib64/ld-linux.so.2", 824 .sysvec = &elf_linux_sysvec, 825 .interp_newpath = NULL, 826 .brand_note = &linux64_brandnote, 827 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 828 }; 829 830 static Elf64_Brandinfo linux_muslbrand = { 831 .brand = ELFOSABI_LINUX, 832 .machine = EM_X86_64, 833 .compat_3_brand = "Linux", 834 .emul_path = "/compat/linux", 835 .interp_path = "/lib/ld-musl-x86_64.so.1", 836 .sysvec = &elf_linux_sysvec, 837 .interp_newpath = NULL, 838 .brand_note = &linux64_brandnote, 839 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 840 }; 841 842 Elf64_Brandinfo *linux_brandlist[] = { 843 &linux_glibc2brand, 844 &linux_glibc2brandshort, 845 &linux_muslbrand, 846 NULL 847 }; 848 849 static int 850 linux64_elf_modevent(module_t mod, int type, void *data) 851 { 852 Elf64_Brandinfo **brandinfo; 853 int error; 854 struct linux_ioctl_handler **lihp; 855 856 error = 0; 857 858 switch(type) { 859 case MOD_LOAD: 860 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 861 ++brandinfo) 862 if (elf64_insert_brand_entry(*brandinfo) < 0) 863 error = EINVAL; 864 if (error == 0) { 865 SET_FOREACH(lihp, linux_ioctl_handler_set) 866 linux_ioctl_register_handler(*lihp); 867 stclohz = (stathz ? stathz : hz); 868 if (bootverbose) 869 printf("Linux x86-64 ELF exec handler installed\n"); 870 } else 871 printf("cannot insert Linux x86-64 ELF brand handler\n"); 872 break; 873 case MOD_UNLOAD: 874 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 875 ++brandinfo) 876 if (elf64_brand_inuse(*brandinfo)) 877 error = EBUSY; 878 if (error == 0) { 879 for (brandinfo = &linux_brandlist[0]; 880 *brandinfo != NULL; ++brandinfo) 881 if (elf64_remove_brand_entry(*brandinfo) < 0) 882 error = EINVAL; 883 } 884 if (error == 0) { 885 SET_FOREACH(lihp, linux_ioctl_handler_set) 886 linux_ioctl_unregister_handler(*lihp); 887 if (bootverbose) 888 printf("Linux ELF exec handler removed\n"); 889 } else 890 printf("Could not deinstall ELF interpreter entry\n"); 891 break; 892 default: 893 return (EOPNOTSUPP); 894 } 895 return (error); 896 } 897 898 static moduledata_t linux64_elf_mod = { 899 "linux64elf", 900 linux64_elf_modevent, 901 0 902 }; 903 904 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 905 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 906 FEATURE(linux64, "Linux 64bit support"); 907