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 static int linux_szsigcode; 89 static vm_object_t linux_shared_page_obj; 90 static char *linux_shared_page_mapping; 91 extern char _binary_linux_locore_o_start; 92 extern char _binary_linux_locore_o_end; 93 94 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 95 96 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 97 98 static int linux_copyout_strings(struct image_params *imgp, 99 uintptr_t *stack_base); 100 static int linux_fixup_elf(uintptr_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 uintptr_t 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]; 200 201 td->td_retval[0] = 0; 202 return (0); 203 } 204 205 static void 206 linux_set_syscall_retval(struct thread *td, int error) 207 { 208 struct trapframe *frame; 209 210 frame = td->td_frame; 211 212 switch (error) { 213 case 0: 214 frame->tf_rax = td->td_retval[0]; 215 frame->tf_r10 = frame->tf_rcx; 216 break; 217 218 case ERESTART: 219 /* 220 * Reconstruct pc, we know that 'syscall' is 2 bytes, 221 * lcall $X,y is 7 bytes, int 0x80 is 2 bytes. 222 * We saved this in tf_err. 223 * 224 */ 225 frame->tf_rip -= frame->tf_err; 226 frame->tf_r10 = frame->tf_rcx; 227 break; 228 229 case EJUSTRETURN: 230 break; 231 232 default: 233 frame->tf_rax = bsd_to_linux_errno(error); 234 frame->tf_r10 = frame->tf_rcx; 235 break; 236 } 237 238 /* 239 * Differently from FreeBSD native ABI, on Linux only %rcx 240 * and %r11 values are not preserved across the syscall. 241 * Require full context restore to get all registers except 242 * those two restored at return to usermode. 243 * 244 * XXX: Would be great to be able to avoid PCB_FULL_IRET 245 * for the error == 0 case. 246 */ 247 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 248 } 249 250 static int 251 linux_copyout_auxargs(struct image_params *imgp, uintptr_t base) 252 { 253 Elf_Auxargs *args; 254 Elf_Auxinfo *argarray, *pos; 255 struct proc *p; 256 int error, issetugid; 257 258 p = imgp->proc; 259 args = (Elf64_Auxargs *)imgp->auxargs; 260 argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP, 261 M_WAITOK | M_ZERO); 262 263 issetugid = p->p_flag & P_SUGID ? 1 : 0; 264 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 265 imgp->proc->p_sysent->sv_shared_page_base); 266 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 267 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 268 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 269 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 270 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 271 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 272 AUXARGS_ENTRY(pos, AT_BASE, args->base); 273 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 274 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 275 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 276 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 277 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 278 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 279 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 280 AUXARGS_ENTRY_PTR(pos, LINUX_AT_RANDOM, imgp->canary); 281 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP2, 0); 282 if (imgp->execpathp != 0) 283 AUXARGS_ENTRY_PTR(pos, LINUX_AT_EXECFN, imgp->execpathp); 284 if (args->execfd != -1) 285 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 286 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 287 AUXARGS_ENTRY(pos, AT_NULL, 0); 288 289 free(imgp->auxargs, M_TEMP); 290 imgp->auxargs = NULL; 291 KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs")); 292 293 error = copyout(argarray, (void *)base, 294 sizeof(*argarray) * LINUX_AT_COUNT); 295 free(argarray, M_TEMP); 296 return (error); 297 } 298 299 static int 300 linux_fixup_elf(uintptr_t *stack_base, struct image_params *imgp) 301 { 302 Elf_Addr *base; 303 304 base = (Elf64_Addr *)*stack_base; 305 base--; 306 if (suword(base, (uint64_t)imgp->args->argc) == -1) 307 return (EFAULT); 308 309 *stack_base = (uintptr_t)base; 310 return (0); 311 } 312 313 /* 314 * Copy strings out to the new process address space, constructing new arg 315 * and env vector tables. Return a pointer to the base so that it can be used 316 * as the initial stack pointer. 317 */ 318 static int 319 linux_copyout_strings(struct image_params *imgp, uintptr_t *stack_base) 320 { 321 int argc, envc, error; 322 char **vectp; 323 char *stringp; 324 uintptr_t destp, ustringp; 325 struct ps_strings *arginfo; 326 char canary[LINUX_AT_RANDOM_LEN]; 327 size_t execpath_len; 328 struct proc *p; 329 330 /* Calculate string base and vector table pointers. */ 331 if (imgp->execpath != NULL && imgp->auxargs != NULL) 332 execpath_len = strlen(imgp->execpath) + 1; 333 else 334 execpath_len = 0; 335 336 p = imgp->proc; 337 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 338 destp = (uintptr_t)arginfo; 339 340 if (execpath_len != 0) { 341 destp -= execpath_len; 342 destp = rounddown2(destp, sizeof(void *)); 343 imgp->execpathp = (void *)destp; 344 error = copyout(imgp->execpath, imgp->execpathp, execpath_len); 345 if (error != 0) 346 return (error); 347 } 348 349 /* Prepare the canary for SSP. */ 350 arc4rand(canary, sizeof(canary), 0); 351 destp -= roundup(sizeof(canary), sizeof(void *)); 352 imgp->canary = (void *)destp; 353 error = copyout(canary, imgp->canary, sizeof(canary)); 354 if (error != 0) 355 return (error); 356 357 /* Allocate room for the argument and environment strings. */ 358 destp -= ARG_MAX - imgp->args->stringspace; 359 destp = rounddown2(destp, sizeof(void *)); 360 ustringp = destp; 361 362 if (imgp->auxargs) { 363 /* 364 * Allocate room on the stack for the ELF auxargs 365 * array. It has LINUX_AT_COUNT entries. 366 */ 367 destp -= LINUX_AT_COUNT * sizeof(Elf64_Auxinfo); 368 destp = rounddown2(destp, sizeof(void *)); 369 } 370 371 vectp = (char **)destp; 372 373 /* 374 * Allocate room for the argv[] and env vectors including the 375 * terminating NULL pointers. 376 */ 377 vectp -= imgp->args->argc + 1 + imgp->args->envc + 1; 378 379 /* 380 * Starting with 2.24, glibc depends on a 16-byte stack alignment. 381 * One "long argc" will be prepended later. 382 */ 383 vectp = (char **)((((uintptr_t)vectp + 8) & ~0xF) - 8); 384 385 /* vectp also becomes our initial stack base. */ 386 *stack_base = (uintptr_t)vectp; 387 388 stringp = imgp->args->begin_argv; 389 argc = imgp->args->argc; 390 envc = imgp->args->envc; 391 392 /* Copy out strings - arguments and environment. */ 393 error = copyout(stringp, (void *)ustringp, 394 ARG_MAX - imgp->args->stringspace); 395 if (error != 0) 396 return (error); 397 398 /* Fill in "ps_strings" struct for ps, w, etc. */ 399 if (suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp) != 0 || 400 suword(&arginfo->ps_nargvstr, argc) != 0) 401 return (EFAULT); 402 403 /* Fill in argument portion of vector table. */ 404 for (; argc > 0; --argc) { 405 if (suword(vectp++, ustringp) != 0) 406 return (EFAULT); 407 while (*stringp++ != 0) 408 ustringp++; 409 ustringp++; 410 } 411 412 /* A null vector table pointer separates the argp's from the envp's. */ 413 if (suword(vectp++, 0) != 0) 414 return (EFAULT); 415 416 if (suword(&arginfo->ps_envstr, (long)(intptr_t)vectp) != 0 || 417 suword(&arginfo->ps_nenvstr, envc) != 0) 418 return (EFAULT); 419 420 /* Fill in environment portion of vector table. */ 421 for (; envc > 0; --envc) { 422 if (suword(vectp++, ustringp) != 0) 423 return (EFAULT); 424 while (*stringp++ != 0) 425 ustringp++; 426 ustringp++; 427 } 428 429 /* The end of the vector table is a null pointer. */ 430 if (suword(vectp, 0) != 0) 431 return (EFAULT); 432 433 if (imgp->auxargs) { 434 vectp++; 435 error = imgp->sysent->sv_copyout_auxargs(imgp, 436 (uintptr_t)vectp); 437 if (error != 0) 438 return (error); 439 } 440 441 return (0); 442 } 443 444 /* 445 * Reset registers to default values on exec. 446 */ 447 static void 448 linux_exec_setregs(struct thread *td, struct image_params *imgp, 449 uintptr_t stack) 450 { 451 struct trapframe *regs; 452 struct pcb *pcb; 453 register_t saved_rflags; 454 455 regs = td->td_frame; 456 pcb = td->td_pcb; 457 458 if (td->td_proc->p_md.md_ldt != NULL) 459 user_ldt_free(td); 460 461 pcb->pcb_fsbase = 0; 462 pcb->pcb_gsbase = 0; 463 clear_pcb_flags(pcb, PCB_32BIT); 464 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 465 set_pcb_flags(pcb, PCB_FULL_IRET); 466 467 saved_rflags = regs->tf_rflags & PSL_T; 468 bzero((char *)regs, sizeof(struct trapframe)); 469 regs->tf_rip = imgp->entry_addr; 470 regs->tf_rsp = stack; 471 regs->tf_rflags = PSL_USER | saved_rflags; 472 regs->tf_ss = _udatasel; 473 regs->tf_cs = _ucodesel; 474 regs->tf_ds = _udatasel; 475 regs->tf_es = _udatasel; 476 regs->tf_fs = _ufssel; 477 regs->tf_gs = _ugssel; 478 regs->tf_flags = TF_HASSEGS; 479 480 x86_clear_dbregs(pcb); 481 482 /* 483 * Drop the FP state if we hold it, so that the process gets a 484 * clean FP state if it uses the FPU again. 485 */ 486 fpstate_drop(td); 487 } 488 489 /* 490 * Copied from amd64/amd64/machdep.c 491 * 492 * XXX fpu state need? don't think so 493 */ 494 int 495 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 496 { 497 struct proc *p; 498 struct l_ucontext uc; 499 struct l_sigcontext *context; 500 struct trapframe *regs; 501 unsigned long rflags; 502 int error; 503 ksiginfo_t ksi; 504 505 regs = td->td_frame; 506 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 507 if (error != 0) 508 return (error); 509 510 p = td->td_proc; 511 context = &uc.uc_mcontext; 512 rflags = context->sc_rflags; 513 514 /* 515 * Don't allow users to change privileged or reserved flags. 516 */ 517 /* 518 * XXX do allow users to change the privileged flag PSL_RF. 519 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 520 * should sometimes set it there too. tf_rflags is kept in 521 * the signal context during signal handling and there is no 522 * other place to remember it, so the PSL_RF bit may be 523 * corrupted by the signal handler without us knowing. 524 * Corruption of the PSL_RF bit at worst causes one more or 525 * one less debugger trap, so allowing it is fairly harmless. 526 */ 527 528 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 529 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 530 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 531 return (EINVAL); 532 } 533 534 /* 535 * Don't allow users to load a valid privileged %cs. Let the 536 * hardware check for invalid selectors, excess privilege in 537 * other selectors, invalid %eip's and invalid %esp's. 538 */ 539 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 540 if (!CS_SECURE(context->sc_cs)) { 541 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 542 ksiginfo_init_trap(&ksi); 543 ksi.ksi_signo = SIGBUS; 544 ksi.ksi_code = BUS_OBJERR; 545 ksi.ksi_trapno = T_PROTFLT; 546 ksi.ksi_addr = (void *)regs->tf_rip; 547 trapsignal(td, &ksi); 548 return (EINVAL); 549 } 550 551 PROC_LOCK(p); 552 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 553 SIG_CANTMASK(td->td_sigmask); 554 signotify(td); 555 PROC_UNLOCK(p); 556 557 regs->tf_rdi = context->sc_rdi; 558 regs->tf_rsi = context->sc_rsi; 559 regs->tf_rdx = context->sc_rdx; 560 regs->tf_rbp = context->sc_rbp; 561 regs->tf_rbx = context->sc_rbx; 562 regs->tf_rcx = context->sc_rcx; 563 regs->tf_rax = context->sc_rax; 564 regs->tf_rip = context->sc_rip; 565 regs->tf_rsp = context->sc_rsp; 566 regs->tf_r8 = context->sc_r8; 567 regs->tf_r9 = context->sc_r9; 568 regs->tf_r10 = context->sc_r10; 569 regs->tf_r11 = context->sc_r11; 570 regs->tf_r12 = context->sc_r12; 571 regs->tf_r13 = context->sc_r13; 572 regs->tf_r14 = context->sc_r14; 573 regs->tf_r15 = context->sc_r15; 574 regs->tf_cs = context->sc_cs; 575 regs->tf_err = context->sc_err; 576 regs->tf_rflags = rflags; 577 578 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 579 return (EJUSTRETURN); 580 } 581 582 /* 583 * copied from amd64/amd64/machdep.c 584 * 585 * Send an interrupt to process. 586 */ 587 static void 588 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 589 { 590 struct l_rt_sigframe sf, *sfp; 591 struct proc *p; 592 struct thread *td; 593 struct sigacts *psp; 594 caddr_t sp; 595 struct trapframe *regs; 596 int sig, code; 597 int oonstack; 598 599 td = curthread; 600 p = td->td_proc; 601 PROC_LOCK_ASSERT(p, MA_OWNED); 602 sig = ksi->ksi_signo; 603 psp = p->p_sigacts; 604 code = ksi->ksi_code; 605 mtx_assert(&psp->ps_mtx, MA_OWNED); 606 regs = td->td_frame; 607 oonstack = sigonstack(regs->tf_rsp); 608 609 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 610 catcher, sig, mask, code); 611 612 /* Translate the signal. */ 613 sig = bsd_to_linux_signal(sig); 614 615 /* Save user context. */ 616 bzero(&sf, sizeof(sf)); 617 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 618 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 619 620 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 621 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 622 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 623 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 624 625 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 626 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 627 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 628 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 629 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 630 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 631 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 632 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 633 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 634 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 635 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 636 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 637 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 638 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 639 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 640 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 641 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 642 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 643 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 644 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 645 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 646 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 647 648 /* Allocate space for the signal handler context. */ 649 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 650 SIGISMEMBER(psp->ps_sigonstack, sig)) { 651 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 652 sizeof(struct l_rt_sigframe); 653 } else 654 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 655 /* Align to 16 bytes. */ 656 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 657 658 /* Build the argument list for the signal handler. */ 659 regs->tf_rdi = sig; /* arg 1 in %rdi */ 660 regs->tf_rax = 0; 661 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 662 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 663 664 /* Fill in POSIX parts. */ 665 siginfo_to_lsiginfo(&ksi->ksi_info, &sf.sf_si, sig); 666 sf.sf_handler = catcher; 667 668 mtx_unlock(&psp->ps_mtx); 669 PROC_UNLOCK(p); 670 671 /* Copy the sigframe out to the user's stack. */ 672 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 673 PROC_LOCK(p); 674 sigexit(td, SIGILL); 675 } 676 677 regs->tf_rsp = (long)sfp; 678 regs->tf_rip = linux_rt_sigcode; 679 regs->tf_rflags &= ~(PSL_T | PSL_D); 680 regs->tf_cs = _ucodesel; 681 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 682 PROC_LOCK(p); 683 mtx_lock(&psp->ps_mtx); 684 } 685 686 #define LINUX_VSYSCALL_START (-10UL << 20) 687 #define LINUX_VSYSCALL_SZ 1024 688 689 const unsigned long linux_vsyscall_vector[] = { 690 LINUX_SYS_gettimeofday, 691 LINUX_SYS_linux_time, 692 LINUX_SYS_linux_getcpu, 693 }; 694 695 static int 696 linux_vsyscall(struct thread *td) 697 { 698 struct trapframe *frame; 699 uint64_t retqaddr; 700 int code, traced; 701 int error; 702 703 frame = td->td_frame; 704 705 /* Check %rip for vsyscall area. */ 706 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 707 return (EINVAL); 708 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 709 return (EINVAL); 710 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 711 if (code >= nitems(linux_vsyscall_vector)) 712 return (EINVAL); 713 714 /* 715 * vsyscall called as callq *(%rax), so we must 716 * use return address from %rsp and also fixup %rsp. 717 */ 718 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 719 if (error) 720 return (error); 721 722 frame->tf_rip = retqaddr; 723 frame->tf_rax = linux_vsyscall_vector[code]; 724 frame->tf_rsp += 8; 725 726 traced = (frame->tf_flags & PSL_T); 727 728 amd64_syscall(td, traced); 729 730 return (0); 731 } 732 733 struct sysentvec elf_linux_sysvec = { 734 .sv_size = LINUX_SYS_MAXSYSCALL, 735 .sv_table = linux_sysent, 736 .sv_transtrap = linux_translate_traps, 737 .sv_fixup = linux_fixup_elf, 738 .sv_sendsig = linux_rt_sendsig, 739 .sv_sigcode = &_binary_linux_locore_o_start, 740 .sv_szsigcode = &linux_szsigcode, 741 .sv_name = "Linux ELF64", 742 .sv_coredump = elf64_coredump, 743 .sv_elf_core_osabi = ELFOSABI_NONE, 744 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR, 745 .sv_elf_core_prepare_notes = elf64_prepare_notes, 746 .sv_imgact_try = linux_exec_imgact_try, 747 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 748 .sv_minuser = VM_MIN_ADDRESS, 749 .sv_maxuser = VM_MAXUSER_ADDRESS_LA48, 750 .sv_usrstack = USRSTACK_LA48, 751 .sv_psstrings = PS_STRINGS_LA48, 752 .sv_stackprot = VM_PROT_ALL, 753 .sv_copyout_auxargs = linux_copyout_auxargs, 754 .sv_copyout_strings = linux_copyout_strings, 755 .sv_setregs = linux_exec_setregs, 756 .sv_fixlimit = NULL, 757 .sv_maxssiz = NULL, 758 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN | 759 SV_SIG_WAITNDQ, 760 .sv_set_syscall_retval = linux_set_syscall_retval, 761 .sv_fetch_syscall_args = linux_fetch_syscall_args, 762 .sv_syscallnames = NULL, 763 .sv_shared_page_base = SHAREDPAGE_LA48, 764 .sv_shared_page_len = PAGE_SIZE, 765 .sv_schedtail = linux_schedtail, 766 .sv_thread_detach = linux_thread_detach, 767 .sv_trap = linux_vsyscall, 768 .sv_onexec = linux_on_exec, 769 .sv_onexit = linux_on_exit, 770 .sv_ontdexit = linux_thread_dtor, 771 .sv_setid_allowed = &linux_setid_allowed_query, 772 }; 773 774 static void 775 linux_vdso_install(void *param) 776 { 777 778 amd64_lower_shared_page(&elf_linux_sysvec); 779 780 linux_szsigcode = (&_binary_linux_locore_o_end - 781 &_binary_linux_locore_o_start); 782 783 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 784 panic("Linux invalid vdso size\n"); 785 786 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 787 788 linux_shared_page_obj = __elfN(linux_shared_page_init) 789 (&linux_shared_page_mapping); 790 791 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 792 793 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 794 linux_szsigcode); 795 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 796 } 797 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 798 linux_vdso_install, NULL); 799 800 static void 801 linux_vdso_deinstall(void *param) 802 { 803 804 __elfN(linux_shared_page_fini)(linux_shared_page_obj, 805 linux_shared_page_mapping); 806 } 807 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 808 linux_vdso_deinstall, NULL); 809 810 static char GNULINUX_ABI_VENDOR[] = "GNU"; 811 static int GNULINUX_ABI_DESC = 0; 812 813 static bool 814 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 815 { 816 const Elf32_Word *desc; 817 uintptr_t p; 818 819 p = (uintptr_t)(note + 1); 820 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 821 822 desc = (const Elf32_Word *)p; 823 if (desc[0] != GNULINUX_ABI_DESC) 824 return (false); 825 826 /* 827 * For Linux we encode osrel using the Linux convention of 828 * (version << 16) | (major << 8) | (minor) 829 * See macro in linux_mib.h 830 */ 831 *osrel = LINUX_KERNVER(desc[1], desc[2], desc[3]); 832 833 return (true); 834 } 835 836 static Elf_Brandnote linux64_brandnote = { 837 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 838 .hdr.n_descsz = 16, 839 .hdr.n_type = 1, 840 .vendor = GNULINUX_ABI_VENDOR, 841 .flags = BN_TRANSLATE_OSREL, 842 .trans_osrel = linux_trans_osrel 843 }; 844 845 static Elf64_Brandinfo linux_glibc2brand = { 846 .brand = ELFOSABI_LINUX, 847 .machine = EM_X86_64, 848 .compat_3_brand = "Linux", 849 .emul_path = linux_emul_path, 850 .interp_path = "/lib64/ld-linux-x86-64.so.2", 851 .sysvec = &elf_linux_sysvec, 852 .interp_newpath = NULL, 853 .brand_note = &linux64_brandnote, 854 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 855 }; 856 857 static Elf64_Brandinfo linux_glibc2brandshort = { 858 .brand = ELFOSABI_LINUX, 859 .machine = EM_X86_64, 860 .compat_3_brand = "Linux", 861 .emul_path = linux_emul_path, 862 .interp_path = "/lib64/ld-linux.so.2", 863 .sysvec = &elf_linux_sysvec, 864 .interp_newpath = NULL, 865 .brand_note = &linux64_brandnote, 866 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 867 }; 868 869 static Elf64_Brandinfo linux_muslbrand = { 870 .brand = ELFOSABI_LINUX, 871 .machine = EM_X86_64, 872 .compat_3_brand = "Linux", 873 .emul_path = linux_emul_path, 874 .interp_path = "/lib/ld-musl-x86_64.so.1", 875 .sysvec = &elf_linux_sysvec, 876 .interp_newpath = NULL, 877 .brand_note = &linux64_brandnote, 878 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 879 }; 880 881 Elf64_Brandinfo *linux_brandlist[] = { 882 &linux_glibc2brand, 883 &linux_glibc2brandshort, 884 &linux_muslbrand, 885 NULL 886 }; 887 888 static int 889 linux64_elf_modevent(module_t mod, int type, void *data) 890 { 891 Elf64_Brandinfo **brandinfo; 892 int error; 893 struct linux_ioctl_handler **lihp; 894 895 error = 0; 896 897 switch(type) { 898 case MOD_LOAD: 899 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 900 ++brandinfo) 901 if (elf64_insert_brand_entry(*brandinfo) < 0) 902 error = EINVAL; 903 if (error == 0) { 904 SET_FOREACH(lihp, linux_ioctl_handler_set) 905 linux_ioctl_register_handler(*lihp); 906 stclohz = (stathz ? stathz : hz); 907 if (bootverbose) 908 printf("Linux x86-64 ELF exec handler installed\n"); 909 } else 910 printf("cannot insert Linux x86-64 ELF brand handler\n"); 911 break; 912 case MOD_UNLOAD: 913 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 914 ++brandinfo) 915 if (elf64_brand_inuse(*brandinfo)) 916 error = EBUSY; 917 if (error == 0) { 918 for (brandinfo = &linux_brandlist[0]; 919 *brandinfo != NULL; ++brandinfo) 920 if (elf64_remove_brand_entry(*brandinfo) < 0) 921 error = EINVAL; 922 } 923 if (error == 0) { 924 SET_FOREACH(lihp, linux_ioctl_handler_set) 925 linux_ioctl_unregister_handler(*lihp); 926 if (bootverbose) 927 printf("Linux ELF exec handler removed\n"); 928 } else 929 printf("Could not deinstall ELF interpreter entry\n"); 930 break; 931 default: 932 return (EOPNOTSUPP); 933 } 934 return (error); 935 } 936 937 static moduledata_t linux64_elf_mod = { 938 "linux64elf", 939 linux64_elf_modevent, 940 0 941 }; 942 943 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 944 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 945 FEATURE(linux64, "Linux 64bit support"); 946