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_futex.h> 79 #include <compat/linux/linux_ioctl.h> 80 #include <compat/linux/linux_mib.h> 81 #include <compat/linux/linux_misc.h> 82 #include <compat/linux/linux_signal.h> 83 #include <compat/linux/linux_sysproto.h> 84 #include <compat/linux/linux_util.h> 85 #include <compat/linux/linux_vdso.h> 86 87 MODULE_VERSION(linux64, 1); 88 89 const char *linux_kplatform; 90 static int linux_szsigcode; 91 static vm_object_t linux_shared_page_obj; 92 static char *linux_shared_page_mapping; 93 extern char _binary_linux_locore_o_start; 94 extern char _binary_linux_locore_o_end; 95 96 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 97 98 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 99 100 static register_t * linux_copyout_strings(struct image_params *imgp); 101 static int linux_fixup_elf(register_t **stack_base, 102 struct image_params *iparams); 103 static bool linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 104 static void linux_vdso_install(void *param); 105 static void linux_vdso_deinstall(void *param); 106 static void linux_set_syscall_retval(struct thread *td, int error); 107 static int linux_fetch_syscall_args(struct thread *td); 108 static void linux_exec_setregs(struct thread *td, struct image_params *imgp, 109 u_long stack); 110 static int linux_vsyscall(struct thread *td); 111 112 #define LINUX_T_UNKNOWN 255 113 static int _bsd_to_linux_trapcode[] = { 114 LINUX_T_UNKNOWN, /* 0 */ 115 6, /* 1 T_PRIVINFLT */ 116 LINUX_T_UNKNOWN, /* 2 */ 117 3, /* 3 T_BPTFLT */ 118 LINUX_T_UNKNOWN, /* 4 */ 119 LINUX_T_UNKNOWN, /* 5 */ 120 16, /* 6 T_ARITHTRAP */ 121 254, /* 7 T_ASTFLT */ 122 LINUX_T_UNKNOWN, /* 8 */ 123 13, /* 9 T_PROTFLT */ 124 1, /* 10 T_TRCTRAP */ 125 LINUX_T_UNKNOWN, /* 11 */ 126 14, /* 12 T_PAGEFLT */ 127 LINUX_T_UNKNOWN, /* 13 */ 128 17, /* 14 T_ALIGNFLT */ 129 LINUX_T_UNKNOWN, /* 15 */ 130 LINUX_T_UNKNOWN, /* 16 */ 131 LINUX_T_UNKNOWN, /* 17 */ 132 0, /* 18 T_DIVIDE */ 133 2, /* 19 T_NMI */ 134 4, /* 20 T_OFLOW */ 135 5, /* 21 T_BOUND */ 136 7, /* 22 T_DNA */ 137 8, /* 23 T_DOUBLEFLT */ 138 9, /* 24 T_FPOPFLT */ 139 10, /* 25 T_TSSFLT */ 140 11, /* 26 T_SEGNPFLT */ 141 12, /* 27 T_STKFLT */ 142 18, /* 28 T_MCHK */ 143 19, /* 29 T_XMMFLT */ 144 15 /* 30 T_RESERVED */ 145 }; 146 #define bsd_to_linux_trapcode(code) \ 147 ((code)<nitems(_bsd_to_linux_trapcode)? \ 148 _bsd_to_linux_trapcode[(code)]: \ 149 LINUX_T_UNKNOWN) 150 151 LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 152 LINUX_VDSO_SYM_CHAR(linux_platform); 153 154 /* 155 * If FreeBSD & Linux have a difference of opinion about what a trap 156 * means, deal with it here. 157 * 158 * MPSAFE 159 */ 160 static int 161 linux_translate_traps(int signal, int trap_code) 162 { 163 164 if (signal != SIGBUS) 165 return (signal); 166 switch (trap_code) { 167 case T_PROTFLT: 168 case T_TSSFLT: 169 case T_DOUBLEFLT: 170 case T_PAGEFLT: 171 return (SIGSEGV); 172 default: 173 return (signal); 174 } 175 } 176 177 static int 178 linux_fetch_syscall_args(struct thread *td) 179 { 180 struct proc *p; 181 struct trapframe *frame; 182 struct syscall_args *sa; 183 184 p = td->td_proc; 185 frame = td->td_frame; 186 sa = &td->td_sa; 187 188 sa->args[0] = frame->tf_rdi; 189 sa->args[1] = frame->tf_rsi; 190 sa->args[2] = frame->tf_rdx; 191 sa->args[3] = frame->tf_rcx; 192 sa->args[4] = frame->tf_r8; 193 sa->args[5] = frame->tf_r9; 194 sa->code = frame->tf_rax; 195 196 if (sa->code >= p->p_sysent->sv_size) 197 /* nosys */ 198 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 199 else 200 sa->callp = &p->p_sysent->sv_table[sa->code]; 201 sa->narg = sa->callp->sy_narg; 202 203 td->td_retval[0] = 0; 204 return (0); 205 } 206 207 static void 208 linux_set_syscall_retval(struct thread *td, int error) 209 { 210 struct trapframe *frame = td->td_frame; 211 212 /* 213 * On Linux only %rcx and %r11 values are not preserved across 214 * the syscall. So, do not clobber %rdx and %r10. 215 */ 216 td->td_retval[1] = frame->tf_rdx; 217 if (error != EJUSTRETURN) 218 frame->tf_r10 = frame->tf_rcx; 219 220 cpu_set_syscall_retval(td, error); 221 222 /* Restore all registers. */ 223 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 224 } 225 226 static int 227 linux_fixup_elf(register_t **stack_base, struct image_params *imgp) 228 { 229 Elf_Auxargs *args; 230 Elf_Auxinfo *argarray, *pos; 231 Elf_Addr *auxbase, *base; 232 struct ps_strings *arginfo; 233 struct proc *p; 234 int error, issetugid; 235 236 p = imgp->proc; 237 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 238 239 KASSERT(curthread->td_proc == imgp->proc, 240 ("unsafe linux_fixup_elf(), should be curproc")); 241 base = (Elf64_Addr *)*stack_base; 242 args = (Elf64_Auxargs *)imgp->auxargs; 243 auxbase = base + imgp->args->argc + 1 + imgp->args->envc + 1; 244 argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP, 245 M_WAITOK | M_ZERO); 246 247 issetugid = p->p_flag & P_SUGID ? 1 : 0; 248 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 249 imgp->proc->p_sysent->sv_shared_page_base); 250 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 251 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 252 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 253 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 254 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 255 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 256 AUXARGS_ENTRY(pos, AT_BASE, args->base); 257 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 258 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 259 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 260 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 261 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 262 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 263 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 264 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 265 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 266 if (imgp->execpathp != 0) 267 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 268 if (args->execfd != -1) 269 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 270 AUXARGS_ENTRY(pos, AT_NULL, 0); 271 free(imgp->auxargs, M_TEMP); 272 imgp->auxargs = NULL; 273 KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs")); 274 275 error = copyout(argarray, auxbase, sizeof(*argarray) * LINUX_AT_COUNT); 276 free(argarray, M_TEMP); 277 if (error != 0) 278 return (error); 279 280 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 if (imgp->auxargs) { 332 /* 333 * Allocate room on the stack for the ELF auxargs 334 * array. It has LINUX_AT_COUNT entries. 335 */ 336 vectp -= howmany(LINUX_AT_COUNT * sizeof(Elf64_Auxinfo), 337 sizeof(*vectp)); 338 } 339 340 /* 341 * Allocate room for the argv[] and env vectors including the 342 * terminating NULL pointers. 343 */ 344 vectp -= imgp->args->argc + 1 + imgp->args->envc + 1; 345 346 /* 347 * Starting with 2.24, glibc depends on a 16-byte stack alignment. 348 * One "long argc" will be prepended later. 349 */ 350 vectp = (char **)((((uintptr_t)vectp + 8) & ~0xF) - 8); 351 352 /* vectp also becomes our initial stack base. */ 353 stack_base = (register_t *)vectp; 354 355 stringp = imgp->args->begin_argv; 356 argc = imgp->args->argc; 357 envc = imgp->args->envc; 358 359 /* Copy out strings - arguments and environment. */ 360 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 361 362 /* Fill in "ps_strings" struct for ps, w, etc. */ 363 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 364 suword(&arginfo->ps_nargvstr, argc); 365 366 /* Fill in argument portion of vector table. */ 367 for (; argc > 0; --argc) { 368 suword(vectp++, (long)(intptr_t)destp); 369 while (*stringp++ != 0) 370 destp++; 371 destp++; 372 } 373 374 /* A null vector table pointer separates the argp's from the envp's. */ 375 suword(vectp++, 0); 376 377 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 378 suword(&arginfo->ps_nenvstr, envc); 379 380 /* Fill in environment portion of vector table. */ 381 for (; envc > 0; --envc) { 382 suword(vectp++, (long)(intptr_t)destp); 383 while (*stringp++ != 0) 384 destp++; 385 destp++; 386 } 387 388 /* The end of the vector table is a null pointer. */ 389 suword(vectp, 0); 390 return (stack_base); 391 } 392 393 /* 394 * Reset registers to default values on exec. 395 */ 396 static void 397 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 398 { 399 struct trapframe *regs; 400 struct pcb *pcb; 401 register_t saved_rflags; 402 403 regs = td->td_frame; 404 pcb = td->td_pcb; 405 406 if (td->td_proc->p_md.md_ldt != NULL) 407 user_ldt_free(td); 408 409 pcb->pcb_fsbase = 0; 410 pcb->pcb_gsbase = 0; 411 clear_pcb_flags(pcb, PCB_32BIT); 412 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 413 set_pcb_flags(pcb, PCB_FULL_IRET); 414 415 saved_rflags = regs->tf_rflags & PSL_T; 416 bzero((char *)regs, sizeof(struct trapframe)); 417 regs->tf_rip = imgp->entry_addr; 418 regs->tf_rsp = stack; 419 regs->tf_rflags = PSL_USER | saved_rflags; 420 regs->tf_ss = _udatasel; 421 regs->tf_cs = _ucodesel; 422 regs->tf_ds = _udatasel; 423 regs->tf_es = _udatasel; 424 regs->tf_fs = _ufssel; 425 regs->tf_gs = _ugssel; 426 regs->tf_flags = TF_HASSEGS; 427 428 /* 429 * Reset the hardware debug registers if they were in use. 430 * They won't have any meaning for the newly exec'd process. 431 */ 432 if (pcb->pcb_flags & PCB_DBREGS) { 433 pcb->pcb_dr0 = 0; 434 pcb->pcb_dr1 = 0; 435 pcb->pcb_dr2 = 0; 436 pcb->pcb_dr3 = 0; 437 pcb->pcb_dr6 = 0; 438 pcb->pcb_dr7 = 0; 439 if (pcb == curpcb) { 440 /* 441 * Clear the debug registers on the running 442 * CPU, otherwise they will end up affecting 443 * the next process we switch to. 444 */ 445 reset_dbregs(); 446 } 447 clear_pcb_flags(pcb, PCB_DBREGS); 448 } 449 450 /* 451 * Drop the FP state if we hold it, so that the process gets a 452 * clean FP state if it uses the FPU again. 453 */ 454 fpstate_drop(td); 455 } 456 457 /* 458 * Copied from amd64/amd64/machdep.c 459 * 460 * XXX fpu state need? don't think so 461 */ 462 int 463 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 464 { 465 struct proc *p; 466 struct l_ucontext uc; 467 struct l_sigcontext *context; 468 struct trapframe *regs; 469 unsigned long rflags; 470 int error; 471 ksiginfo_t ksi; 472 473 regs = td->td_frame; 474 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 475 if (error != 0) 476 return (error); 477 478 p = td->td_proc; 479 context = &uc.uc_mcontext; 480 rflags = context->sc_rflags; 481 482 /* 483 * Don't allow users to change privileged or reserved flags. 484 */ 485 /* 486 * XXX do allow users to change the privileged flag PSL_RF. 487 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 488 * should sometimes set it there too. tf_rflags is kept in 489 * the signal context during signal handling and there is no 490 * other place to remember it, so the PSL_RF bit may be 491 * corrupted by the signal handler without us knowing. 492 * Corruption of the PSL_RF bit at worst causes one more or 493 * one less debugger trap, so allowing it is fairly harmless. 494 */ 495 496 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 497 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 498 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 499 return (EINVAL); 500 } 501 502 /* 503 * Don't allow users to load a valid privileged %cs. Let the 504 * hardware check for invalid selectors, excess privilege in 505 * other selectors, invalid %eip's and invalid %esp's. 506 */ 507 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 508 if (!CS_SECURE(context->sc_cs)) { 509 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 510 ksiginfo_init_trap(&ksi); 511 ksi.ksi_signo = SIGBUS; 512 ksi.ksi_code = BUS_OBJERR; 513 ksi.ksi_trapno = T_PROTFLT; 514 ksi.ksi_addr = (void *)regs->tf_rip; 515 trapsignal(td, &ksi); 516 return (EINVAL); 517 } 518 519 PROC_LOCK(p); 520 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 521 SIG_CANTMASK(td->td_sigmask); 522 signotify(td); 523 PROC_UNLOCK(p); 524 525 regs->tf_rdi = context->sc_rdi; 526 regs->tf_rsi = context->sc_rsi; 527 regs->tf_rdx = context->sc_rdx; 528 regs->tf_rbp = context->sc_rbp; 529 regs->tf_rbx = context->sc_rbx; 530 regs->tf_rcx = context->sc_rcx; 531 regs->tf_rax = context->sc_rax; 532 regs->tf_rip = context->sc_rip; 533 regs->tf_rsp = context->sc_rsp; 534 regs->tf_r8 = context->sc_r8; 535 regs->tf_r9 = context->sc_r9; 536 regs->tf_r10 = context->sc_r10; 537 regs->tf_r11 = context->sc_r11; 538 regs->tf_r12 = context->sc_r12; 539 regs->tf_r13 = context->sc_r13; 540 regs->tf_r14 = context->sc_r14; 541 regs->tf_r15 = context->sc_r15; 542 regs->tf_cs = context->sc_cs; 543 regs->tf_err = context->sc_err; 544 regs->tf_rflags = rflags; 545 546 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 547 return (EJUSTRETURN); 548 } 549 550 /* 551 * copied from amd64/amd64/machdep.c 552 * 553 * Send an interrupt to process. 554 */ 555 static void 556 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 557 { 558 struct l_rt_sigframe sf, *sfp; 559 struct proc *p; 560 struct thread *td; 561 struct sigacts *psp; 562 caddr_t sp; 563 struct trapframe *regs; 564 int sig, code; 565 int oonstack; 566 567 td = curthread; 568 p = td->td_proc; 569 PROC_LOCK_ASSERT(p, MA_OWNED); 570 sig = ksi->ksi_signo; 571 psp = p->p_sigacts; 572 code = ksi->ksi_code; 573 mtx_assert(&psp->ps_mtx, MA_OWNED); 574 regs = td->td_frame; 575 oonstack = sigonstack(regs->tf_rsp); 576 577 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 578 catcher, sig, mask, code); 579 580 /* Allocate space for the signal handler context. */ 581 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 582 SIGISMEMBER(psp->ps_sigonstack, sig)) { 583 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 584 sizeof(struct l_rt_sigframe); 585 } else 586 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 587 /* Align to 16 bytes. */ 588 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 589 mtx_unlock(&psp->ps_mtx); 590 591 /* Translate the signal. */ 592 sig = bsd_to_linux_signal(sig); 593 594 /* Save user context. */ 595 bzero(&sf, sizeof(sf)); 596 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 597 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 598 599 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 600 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 601 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 602 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 603 PROC_UNLOCK(p); 604 605 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 606 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 607 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 608 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 609 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 610 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 611 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 612 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 613 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 614 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 615 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 616 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 617 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 618 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 619 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 620 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 621 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 622 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 623 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 624 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 625 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 626 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 627 628 /* Build the argument list for the signal handler. */ 629 regs->tf_rdi = sig; /* arg 1 in %rdi */ 630 regs->tf_rax = 0; 631 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 632 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 633 634 sf.sf_handler = catcher; 635 /* Fill in POSIX parts. */ 636 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 637 638 /* Copy the sigframe out to the user's stack. */ 639 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 640 PROC_LOCK(p); 641 sigexit(td, SIGILL); 642 } 643 644 regs->tf_rsp = (long)sfp; 645 regs->tf_rip = linux_rt_sigcode; 646 regs->tf_rflags &= ~(PSL_T | PSL_D); 647 regs->tf_cs = _ucodesel; 648 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 649 PROC_LOCK(p); 650 mtx_lock(&psp->ps_mtx); 651 } 652 653 #define LINUX_VSYSCALL_START (-10UL << 20) 654 #define LINUX_VSYSCALL_SZ 1024 655 656 const unsigned long linux_vsyscall_vector[] = { 657 LINUX_SYS_gettimeofday, 658 LINUX_SYS_linux_time, 659 /* getcpu not implemented */ 660 }; 661 662 static int 663 linux_vsyscall(struct thread *td) 664 { 665 struct trapframe *frame; 666 uint64_t retqaddr; 667 int code, traced; 668 int error; 669 670 frame = td->td_frame; 671 672 /* Check %rip for vsyscall area. */ 673 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 674 return (EINVAL); 675 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 676 return (EINVAL); 677 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 678 if (code >= nitems(linux_vsyscall_vector)) 679 return (EINVAL); 680 681 /* 682 * vsyscall called as callq *(%rax), so we must 683 * use return address from %rsp and also fixup %rsp. 684 */ 685 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 686 if (error) 687 return (error); 688 689 frame->tf_rip = retqaddr; 690 frame->tf_rax = linux_vsyscall_vector[code]; 691 frame->tf_rsp += 8; 692 693 traced = (frame->tf_flags & PSL_T); 694 695 amd64_syscall(td, traced); 696 697 return (0); 698 } 699 700 struct sysentvec elf_linux_sysvec = { 701 .sv_size = LINUX_SYS_MAXSYSCALL, 702 .sv_table = linux_sysent, 703 .sv_errsize = ELAST + 1, 704 .sv_errtbl = linux_errtbl, 705 .sv_transtrap = linux_translate_traps, 706 .sv_fixup = linux_fixup_elf, 707 .sv_sendsig = linux_rt_sendsig, 708 .sv_sigcode = &_binary_linux_locore_o_start, 709 .sv_szsigcode = &linux_szsigcode, 710 .sv_name = "Linux ELF64", 711 .sv_coredump = elf64_coredump, 712 .sv_imgact_try = linux_exec_imgact_try, 713 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 714 .sv_minuser = VM_MIN_ADDRESS, 715 .sv_maxuser = VM_MAXUSER_ADDRESS, 716 .sv_usrstack = USRSTACK, 717 .sv_psstrings = PS_STRINGS, 718 .sv_stackprot = VM_PROT_ALL, 719 .sv_copyout_strings = linux_copyout_strings, 720 .sv_setregs = linux_exec_setregs, 721 .sv_fixlimit = NULL, 722 .sv_maxssiz = NULL, 723 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 724 .sv_set_syscall_retval = linux_set_syscall_retval, 725 .sv_fetch_syscall_args = linux_fetch_syscall_args, 726 .sv_syscallnames = NULL, 727 .sv_shared_page_base = SHAREDPAGE, 728 .sv_shared_page_len = PAGE_SIZE, 729 .sv_schedtail = linux_schedtail, 730 .sv_thread_detach = linux_thread_detach, 731 .sv_trap = linux_vsyscall, 732 }; 733 734 static void 735 linux_vdso_install(void *param) 736 { 737 738 amd64_lower_shared_page(&elf_linux_sysvec); 739 740 linux_szsigcode = (&_binary_linux_locore_o_end - 741 &_binary_linux_locore_o_start); 742 743 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 744 panic("Linux invalid vdso size\n"); 745 746 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 747 748 linux_shared_page_obj = __elfN(linux_shared_page_init) 749 (&linux_shared_page_mapping); 750 751 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 752 753 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 754 linux_szsigcode); 755 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 756 757 linux_kplatform = linux_shared_page_mapping + 758 (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base); 759 } 760 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 761 linux_vdso_install, NULL); 762 763 static void 764 linux_vdso_deinstall(void *param) 765 { 766 767 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 768 } 769 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 770 linux_vdso_deinstall, NULL); 771 772 static char GNULINUX_ABI_VENDOR[] = "GNU"; 773 static int GNULINUX_ABI_DESC = 0; 774 775 static bool 776 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 777 { 778 const Elf32_Word *desc; 779 uintptr_t p; 780 781 p = (uintptr_t)(note + 1); 782 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 783 784 desc = (const Elf32_Word *)p; 785 if (desc[0] != GNULINUX_ABI_DESC) 786 return (false); 787 788 /* 789 * For Linux we encode osrel using the Linux convention of 790 * (version << 16) | (major << 8) | (minor) 791 * See macro in linux_mib.h 792 */ 793 *osrel = LINUX_KERNVER(desc[1], desc[2], desc[3]); 794 795 return (true); 796 } 797 798 static Elf_Brandnote linux64_brandnote = { 799 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 800 .hdr.n_descsz = 16, 801 .hdr.n_type = 1, 802 .vendor = GNULINUX_ABI_VENDOR, 803 .flags = BN_TRANSLATE_OSREL, 804 .trans_osrel = linux_trans_osrel 805 }; 806 807 static Elf64_Brandinfo linux_glibc2brand = { 808 .brand = ELFOSABI_LINUX, 809 .machine = EM_X86_64, 810 .compat_3_brand = "Linux", 811 .emul_path = "/compat/linux", 812 .interp_path = "/lib64/ld-linux-x86-64.so.2", 813 .sysvec = &elf_linux_sysvec, 814 .interp_newpath = NULL, 815 .brand_note = &linux64_brandnote, 816 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 817 }; 818 819 static Elf64_Brandinfo linux_glibc2brandshort = { 820 .brand = ELFOSABI_LINUX, 821 .machine = EM_X86_64, 822 .compat_3_brand = "Linux", 823 .emul_path = "/compat/linux", 824 .interp_path = "/lib64/ld-linux.so.2", 825 .sysvec = &elf_linux_sysvec, 826 .interp_newpath = NULL, 827 .brand_note = &linux64_brandnote, 828 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 829 }; 830 831 static Elf64_Brandinfo linux_muslbrand = { 832 .brand = ELFOSABI_LINUX, 833 .machine = EM_X86_64, 834 .compat_3_brand = "Linux", 835 .emul_path = "/compat/linux", 836 .interp_path = "/lib/ld-musl-x86_64.so.1", 837 .sysvec = &elf_linux_sysvec, 838 .interp_newpath = NULL, 839 .brand_note = &linux64_brandnote, 840 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 841 }; 842 843 Elf64_Brandinfo *linux_brandlist[] = { 844 &linux_glibc2brand, 845 &linux_glibc2brandshort, 846 &linux_muslbrand, 847 NULL 848 }; 849 850 static int 851 linux64_elf_modevent(module_t mod, int type, void *data) 852 { 853 Elf64_Brandinfo **brandinfo; 854 int error; 855 struct linux_ioctl_handler **lihp; 856 857 error = 0; 858 859 switch(type) { 860 case MOD_LOAD: 861 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 862 ++brandinfo) 863 if (elf64_insert_brand_entry(*brandinfo) < 0) 864 error = EINVAL; 865 if (error == 0) { 866 SET_FOREACH(lihp, linux_ioctl_handler_set) 867 linux_ioctl_register_handler(*lihp); 868 LIST_INIT(&futex_list); 869 mtx_init(&futex_mtx, "ftllk64", NULL, MTX_DEF); 870 stclohz = (stathz ? stathz : hz); 871 if (bootverbose) 872 printf("Linux x86-64 ELF exec handler installed\n"); 873 } else 874 printf("cannot insert Linux x86-64 ELF brand handler\n"); 875 break; 876 case MOD_UNLOAD: 877 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 878 ++brandinfo) 879 if (elf64_brand_inuse(*brandinfo)) 880 error = EBUSY; 881 if (error == 0) { 882 for (brandinfo = &linux_brandlist[0]; 883 *brandinfo != NULL; ++brandinfo) 884 if (elf64_remove_brand_entry(*brandinfo) < 0) 885 error = EINVAL; 886 } 887 if (error == 0) { 888 SET_FOREACH(lihp, linux_ioctl_handler_set) 889 linux_ioctl_unregister_handler(*lihp); 890 mtx_destroy(&futex_mtx); 891 if (bootverbose) 892 printf("Linux ELF exec handler removed\n"); 893 } else 894 printf("Could not deinstall ELF interpreter entry\n"); 895 break; 896 default: 897 return (EOPNOTSUPP); 898 } 899 return (error); 900 } 901 902 static moduledata_t linux64_elf_mod = { 903 "linux64elf", 904 linux64_elf_modevent, 905 0 906 }; 907 908 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 909 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 910 FEATURE(linux64, "Linux 64bit support"); 911