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 #include "opt_compat.h" 38 39 #define __ELF_WORD_SIZE 64 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/exec.h> 44 #include <sys/fcntl.h> 45 #include <sys/imgact.h> 46 #include <sys/imgact_elf.h> 47 #include <sys/kernel.h> 48 #include <sys/ktr.h> 49 #include <sys/lock.h> 50 #include <sys/malloc.h> 51 #include <sys/module.h> 52 #include <sys/mutex.h> 53 #include <sys/proc.h> 54 #include <sys/resourcevar.h> 55 #include <sys/signalvar.h> 56 #include <sys/sysctl.h> 57 #include <sys/syscallsubr.h> 58 #include <sys/sysent.h> 59 #include <sys/sysproto.h> 60 #include <sys/vnode.h> 61 #include <sys/eventhandler.h> 62 63 #include <vm/vm.h> 64 #include <vm/pmap.h> 65 #include <vm/vm_extern.h> 66 #include <vm/vm_map.h> 67 #include <vm/vm_object.h> 68 #include <vm/vm_page.h> 69 #include <vm/vm_param.h> 70 71 #include <machine/cpu.h> 72 #include <machine/md_var.h> 73 #include <machine/pcb.h> 74 #include <machine/specialreg.h> 75 76 #include <amd64/linux/linux.h> 77 #include <amd64/linux/linux_proto.h> 78 #include <compat/linux/linux_emul.h> 79 #include <compat/linux/linux_futex.h> 80 #include <compat/linux/linux_ioctl.h> 81 #include <compat/linux/linux_mib.h> 82 #include <compat/linux/linux_misc.h> 83 #include <compat/linux/linux_signal.h> 84 #include <compat/linux/linux_sysproto.h> 85 #include <compat/linux/linux_util.h> 86 #include <compat/linux/linux_vdso.h> 87 88 MODULE_VERSION(linux64, 1); 89 90 #if BYTE_ORDER == LITTLE_ENDIAN 91 #define SHELLMAGIC 0x2123 /* #! */ 92 #else 93 #define SHELLMAGIC 0x2321 94 #endif 95 96 #if defined(DEBUG) 97 SYSCTL_PROC(_compat_linux, OID_AUTO, debug, 98 CTLTYPE_STRING | CTLFLAG_RW, 99 0, 0, linux_sysctl_debug, "A", 100 "Linux 64 debugging control"); 101 #endif 102 103 /* 104 * Allow the this functions to use the ldebug() facility 105 * even though they are not syscalls themselves. Map them 106 * to syscall 0. This is slightly less bogus than using 107 * ldebug(sigreturn). 108 */ 109 #define LINUX_SYS_linux_rt_sendsig 0 110 111 const char *linux_kplatform; 112 static int linux_szsigcode; 113 static vm_object_t linux_shared_page_obj; 114 static char *linux_shared_page_mapping; 115 extern char _binary_linux_locore_o_start; 116 extern char _binary_linux_locore_o_end; 117 118 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 119 120 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 121 122 static register_t * linux_copyout_strings(struct image_params *imgp); 123 static int elf_linux_fixup(register_t **stack_base, 124 struct image_params *iparams); 125 static boolean_t linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 126 static void linux_vdso_install(void *param); 127 static void linux_vdso_deinstall(void *param); 128 static void linux_set_syscall_retval(struct thread *td, int error); 129 static int linux_fetch_syscall_args(struct thread *td, struct syscall_args *sa); 130 static void linux_exec_setregs(struct thread *td, struct image_params *imgp, 131 u_long stack); 132 static int linux_vsyscall(struct thread *td); 133 134 /* 135 * Linux syscalls return negative errno's, we do positive and map them 136 * Reference: 137 * FreeBSD: src/sys/sys/errno.h 138 * Linux: linux-2.6.17.8/include/asm-generic/errno-base.h 139 * linux-2.6.17.8/include/asm-generic/errno.h 140 */ 141 static int bsd_to_linux_errno[ELAST + 1] = { 142 -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, 143 -10, -35, -12, -13, -14, -15, -16, -17, -18, -19, 144 -20, -21, -22, -23, -24, -25, -26, -27, -28, -29, 145 -30, -31, -32, -33, -34, -11,-115,-114, -88, -89, 146 -90, -91, -92, -93, -94, -95, -96, -97, -98, -99, 147 -100,-101,-102,-103,-104,-105,-106,-107,-108,-109, 148 -110,-111, -40, -36,-112,-113, -39, -11, -87,-122, 149 -116, -66, -6, -6, -6, -6, -6, -37, -38, -9, 150 -6, -6, -43, -42, -75,-125, -84, -95, -16, -74, 151 -72, -67, -71 152 }; 153 154 #define LINUX_T_UNKNOWN 255 155 static int _bsd_to_linux_trapcode[] = { 156 LINUX_T_UNKNOWN, /* 0 */ 157 6, /* 1 T_PRIVINFLT */ 158 LINUX_T_UNKNOWN, /* 2 */ 159 3, /* 3 T_BPTFLT */ 160 LINUX_T_UNKNOWN, /* 4 */ 161 LINUX_T_UNKNOWN, /* 5 */ 162 16, /* 6 T_ARITHTRAP */ 163 254, /* 7 T_ASTFLT */ 164 LINUX_T_UNKNOWN, /* 8 */ 165 13, /* 9 T_PROTFLT */ 166 1, /* 10 T_TRCTRAP */ 167 LINUX_T_UNKNOWN, /* 11 */ 168 14, /* 12 T_PAGEFLT */ 169 LINUX_T_UNKNOWN, /* 13 */ 170 17, /* 14 T_ALIGNFLT */ 171 LINUX_T_UNKNOWN, /* 15 */ 172 LINUX_T_UNKNOWN, /* 16 */ 173 LINUX_T_UNKNOWN, /* 17 */ 174 0, /* 18 T_DIVIDE */ 175 2, /* 19 T_NMI */ 176 4, /* 20 T_OFLOW */ 177 5, /* 21 T_BOUND */ 178 7, /* 22 T_DNA */ 179 8, /* 23 T_DOUBLEFLT */ 180 9, /* 24 T_FPOPFLT */ 181 10, /* 25 T_TSSFLT */ 182 11, /* 26 T_SEGNPFLT */ 183 12, /* 27 T_STKFLT */ 184 18, /* 28 T_MCHK */ 185 19, /* 29 T_XMMFLT */ 186 15 /* 30 T_RESERVED */ 187 }; 188 #define bsd_to_linux_trapcode(code) \ 189 ((code)<sizeof(_bsd_to_linux_trapcode)/sizeof(*_bsd_to_linux_trapcode)? \ 190 _bsd_to_linux_trapcode[(code)]: \ 191 LINUX_T_UNKNOWN) 192 193 LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 194 LINUX_VDSO_SYM_CHAR(linux_platform); 195 196 /* 197 * If FreeBSD & Linux have a difference of opinion about what a trap 198 * means, deal with it here. 199 * 200 * MPSAFE 201 */ 202 static int 203 translate_traps(int signal, int trap_code) 204 { 205 206 if (signal != SIGBUS) 207 return signal; 208 switch (trap_code) { 209 case T_PROTFLT: 210 case T_TSSFLT: 211 case T_DOUBLEFLT: 212 case T_PAGEFLT: 213 return SIGSEGV; 214 default: 215 return signal; 216 } 217 } 218 219 static int 220 linux_fetch_syscall_args(struct thread *td, struct syscall_args *sa) 221 { 222 struct proc *p; 223 struct trapframe *frame; 224 225 p = td->td_proc; 226 frame = td->td_frame; 227 228 sa->args[0] = frame->tf_rdi; 229 sa->args[1] = frame->tf_rsi; 230 sa->args[2] = frame->tf_rdx; 231 sa->args[3] = frame->tf_rcx; 232 sa->args[4] = frame->tf_r8; 233 sa->args[5] = frame->tf_r9; 234 sa->code = frame->tf_rax; 235 236 if (sa->code >= p->p_sysent->sv_size) 237 /* nosys */ 238 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 239 else 240 sa->callp = &p->p_sysent->sv_table[sa->code]; 241 sa->narg = sa->callp->sy_narg; 242 243 td->td_retval[0] = 0; 244 return (0); 245 } 246 247 static void 248 linux_set_syscall_retval(struct thread *td, int error) 249 { 250 struct trapframe *frame = td->td_frame; 251 252 /* 253 * On Linux only %rcx and %r11 values are not preserved across 254 * the syscall. 255 * So, do not clobber %rdx and %r10 256 */ 257 td->td_retval[1] = frame->tf_rdx; 258 frame->tf_r10 = frame->tf_rcx; 259 260 cpu_set_syscall_retval(td, error); 261 262 /* Restore all registers. */ 263 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 264 } 265 266 static int 267 elf_linux_fixup(register_t **stack_base, struct image_params *imgp) 268 { 269 Elf_Auxargs *args; 270 Elf_Addr *base; 271 Elf_Addr *pos; 272 struct ps_strings *arginfo; 273 struct proc *p; 274 int issetugid; 275 276 p = imgp->proc; 277 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 278 279 KASSERT(curthread->td_proc == imgp->proc, 280 ("unsafe elf_linux_fixup(), should be curproc")); 281 base = (Elf64_Addr *)*stack_base; 282 args = (Elf64_Auxargs *)imgp->auxargs; 283 pos = base + (imgp->args->argc + imgp->args->envc + 2); 284 285 issetugid = p->p_flag & P_SUGID ? 1 : 0; 286 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 287 imgp->proc->p_sysent->sv_shared_page_base); 288 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 289 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 290 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 291 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 292 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 293 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 294 AUXARGS_ENTRY(pos, AT_BASE, args->base); 295 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 296 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 297 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 298 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 299 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 300 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 301 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 302 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 303 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 304 if (imgp->execpathp != 0) 305 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 306 if (args->execfd != -1) 307 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 308 AUXARGS_ENTRY(pos, AT_NULL, 0); 309 free(imgp->auxargs, M_TEMP); 310 imgp->auxargs = NULL; 311 312 base--; 313 suword(base, (uint64_t)imgp->args->argc); 314 315 *stack_base = (register_t *)base; 316 return (0); 317 } 318 319 /* 320 * Copy strings out to the new process address space, constructing new arg 321 * and env vector tables. Return a pointer to the base so that it can be used 322 * as the initial stack pointer. 323 */ 324 static register_t * 325 linux_copyout_strings(struct image_params *imgp) 326 { 327 int argc, envc; 328 char **vectp; 329 char *stringp, *destp; 330 register_t *stack_base; 331 struct ps_strings *arginfo; 332 char canary[LINUX_AT_RANDOM_LEN]; 333 size_t execpath_len; 334 struct proc *p; 335 336 /* 337 * Calculate string base and vector table pointers. 338 */ 339 if (imgp->execpath != NULL && imgp->auxargs != NULL) 340 execpath_len = strlen(imgp->execpath) + 1; 341 else 342 execpath_len = 0; 343 344 p = imgp->proc; 345 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 346 destp = (caddr_t)arginfo - SPARE_USRSPACE - 347 roundup(sizeof(canary), sizeof(char *)) - 348 roundup(execpath_len, sizeof(char *)) - 349 roundup((ARG_MAX - imgp->args->stringspace), sizeof(char *)); 350 351 if (execpath_len != 0) { 352 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 353 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 354 } 355 356 /* 357 * Prepare the canary for SSP. 358 */ 359 arc4rand(canary, sizeof(canary), 0); 360 imgp->canary = (uintptr_t)arginfo - 361 roundup(execpath_len, sizeof(char *)) - 362 roundup(sizeof(canary), sizeof(char *)); 363 copyout(canary, (void *)imgp->canary, sizeof(canary)); 364 365 /* 366 * If we have a valid auxargs ptr, prepare some room 367 * on the stack. 368 */ 369 if (imgp->auxargs) { 370 /* 371 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for 372 * lower compatibility. 373 */ 374 imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : 375 (LINUX_AT_COUNT * 2); 376 377 /* 378 * The '+ 2' is for the null pointers at the end of each of 379 * the arg and env vector sets,and imgp->auxarg_size is room 380 * for argument of Runtime loader. 381 */ 382 vectp = (char **)(destp - (imgp->args->argc + 383 imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); 384 385 } else { 386 /* 387 * The '+ 2' is for the null pointers at the end of each of 388 * the arg and env vector sets 389 */ 390 vectp = (char **)(destp - (imgp->args->argc + 391 imgp->args->envc + 2) * sizeof(char *)); 392 } 393 394 /* 395 * vectp also becomes our initial stack base 396 */ 397 stack_base = (register_t *)vectp; 398 399 stringp = imgp->args->begin_argv; 400 argc = imgp->args->argc; 401 envc = imgp->args->envc; 402 403 /* 404 * Copy out strings - arguments and environment. 405 */ 406 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 407 408 /* 409 * Fill in "ps_strings" struct for ps, w, etc. 410 */ 411 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 412 suword(&arginfo->ps_nargvstr, argc); 413 414 /* 415 * Fill in argument portion of vector table. 416 */ 417 for (; argc > 0; --argc) { 418 suword(vectp++, (long)(intptr_t)destp); 419 while (*stringp++ != 0) 420 destp++; 421 destp++; 422 } 423 424 /* a null vector table pointer separates the argp's from the envp's */ 425 suword(vectp++, 0); 426 427 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 428 suword(&arginfo->ps_nenvstr, envc); 429 430 /* 431 * Fill in environment portion of vector table. 432 */ 433 for (; envc > 0; --envc) { 434 suword(vectp++, (long)(intptr_t)destp); 435 while (*stringp++ != 0) 436 destp++; 437 destp++; 438 } 439 440 /* end of vector table is a null pointer */ 441 suword(vectp, 0); 442 return (stack_base); 443 } 444 445 /* 446 * Reset registers to default values on exec. 447 */ 448 static void 449 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 450 { 451 struct trapframe *regs = td->td_frame; 452 struct pcb *pcb = td->td_pcb; 453 454 mtx_lock(&dt_lock); 455 if (td->td_proc->p_md.md_ldt != NULL) 456 user_ldt_free(td); 457 else 458 mtx_unlock(&dt_lock); 459 460 pcb->pcb_fsbase = 0; 461 pcb->pcb_gsbase = 0; 462 clear_pcb_flags(pcb, PCB_32BIT); 463 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 464 set_pcb_flags(pcb, PCB_FULL_IRET); 465 466 bzero((char *)regs, sizeof(struct trapframe)); 467 regs->tf_rip = imgp->entry_addr; 468 regs->tf_rsp = stack; 469 regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); 470 regs->tf_ss = _udatasel; 471 regs->tf_cs = _ucodesel; 472 regs->tf_ds = _udatasel; 473 regs->tf_es = _udatasel; 474 regs->tf_fs = _ufssel; 475 regs->tf_gs = _ugssel; 476 regs->tf_flags = TF_HASSEGS; 477 478 /* 479 * Reset the hardware debug registers if they were in use. 480 * They won't have any meaning for the newly exec'd process. 481 */ 482 if (pcb->pcb_flags & PCB_DBREGS) { 483 pcb->pcb_dr0 = 0; 484 pcb->pcb_dr1 = 0; 485 pcb->pcb_dr2 = 0; 486 pcb->pcb_dr3 = 0; 487 pcb->pcb_dr6 = 0; 488 pcb->pcb_dr7 = 0; 489 if (pcb == curpcb) { 490 /* 491 * Clear the debug registers on the running 492 * CPU, otherwise they will end up affecting 493 * the next process we switch to. 494 */ 495 reset_dbregs(); 496 } 497 clear_pcb_flags(pcb, PCB_DBREGS); 498 } 499 500 /* 501 * Drop the FP state if we hold it, so that the process gets a 502 * clean FP state if it uses the FPU again. 503 */ 504 fpstate_drop(td); 505 } 506 507 /* 508 * Copied from amd64/amd64/machdep.c 509 * 510 * XXX fpu state need? don't think so 511 */ 512 int 513 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 514 { 515 struct proc *p; 516 struct l_ucontext uc; 517 struct l_sigcontext *context; 518 struct trapframe *regs; 519 unsigned long rflags; 520 int error; 521 ksiginfo_t ksi; 522 523 regs = td->td_frame; 524 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 525 if (error != 0) 526 return (error); 527 528 p = td->td_proc; 529 context = &uc.uc_mcontext; 530 rflags = context->sc_rflags; 531 532 /* 533 * Don't allow users to change privileged or reserved flags. 534 */ 535 /* 536 * XXX do allow users to change the privileged flag PSL_RF. 537 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 538 * should sometimes set it there too. tf_rflags is kept in 539 * the signal context during signal handling and there is no 540 * other place to remember it, so the PSL_RF bit may be 541 * corrupted by the signal handler without us knowing. 542 * Corruption of the PSL_RF bit at worst causes one more or 543 * one less debugger trap, so allowing it is fairly harmless. 544 */ 545 546 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 547 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 548 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 549 return (EINVAL); 550 } 551 552 /* 553 * Don't allow users to load a valid privileged %cs. Let the 554 * hardware check for invalid selectors, excess privilege in 555 * other selectors, invalid %eip's and invalid %esp's. 556 */ 557 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 558 if (!CS_SECURE(context->sc_cs)) { 559 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 560 ksiginfo_init_trap(&ksi); 561 ksi.ksi_signo = SIGBUS; 562 ksi.ksi_code = BUS_OBJERR; 563 ksi.ksi_trapno = T_PROTFLT; 564 ksi.ksi_addr = (void *)regs->tf_rip; 565 trapsignal(td, &ksi); 566 return (EINVAL); 567 } 568 569 PROC_LOCK(p); 570 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 571 SIG_CANTMASK(td->td_sigmask); 572 signotify(td); 573 PROC_UNLOCK(p); 574 575 regs->tf_rdi = context->sc_rdi; 576 regs->tf_rsi = context->sc_rsi; 577 regs->tf_rdx = context->sc_rdx; 578 regs->tf_rbp = context->sc_rbp; 579 regs->tf_rbx = context->sc_rbx; 580 regs->tf_rcx = context->sc_rcx; 581 regs->tf_rax = context->sc_rax; 582 regs->tf_rip = context->sc_rip; 583 regs->tf_rsp = context->sc_rsp; 584 regs->tf_r8 = context->sc_r8; 585 regs->tf_r9 = context->sc_r9; 586 regs->tf_r10 = context->sc_r10; 587 regs->tf_r11 = context->sc_r11; 588 regs->tf_r12 = context->sc_r12; 589 regs->tf_r13 = context->sc_r13; 590 regs->tf_r14 = context->sc_r14; 591 regs->tf_r15 = context->sc_r15; 592 regs->tf_cs = context->sc_cs; 593 regs->tf_err = context->sc_err; 594 regs->tf_rflags = rflags; 595 596 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 597 return (EJUSTRETURN); 598 } 599 600 /* 601 * copied from amd64/amd64/machdep.c 602 * 603 * Send an interrupt to process. 604 */ 605 static void 606 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 607 { 608 struct l_rt_sigframe sf, *sfp; 609 struct proc *p; 610 struct thread *td; 611 struct sigacts *psp; 612 caddr_t sp; 613 struct trapframe *regs; 614 int sig, code; 615 int oonstack; 616 617 td = curthread; 618 p = td->td_proc; 619 PROC_LOCK_ASSERT(p, MA_OWNED); 620 sig = ksi->ksi_signo; 621 psp = p->p_sigacts; 622 code = ksi->ksi_code; 623 mtx_assert(&psp->ps_mtx, MA_OWNED); 624 regs = td->td_frame; 625 oonstack = sigonstack(regs->tf_rsp); 626 627 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 628 catcher, sig, mask, code); 629 630 /* Allocate space for the signal handler context. */ 631 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 632 SIGISMEMBER(psp->ps_sigonstack, sig)) { 633 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 634 sizeof(struct l_rt_sigframe); 635 } else 636 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 637 /* Align to 16 bytes. */ 638 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 639 mtx_unlock(&psp->ps_mtx); 640 641 /* Translate the signal. */ 642 sig = bsd_to_linux_signal(sig); 643 644 /* Save user context. */ 645 bzero(&sf, sizeof(sf)); 646 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 647 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 648 649 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 650 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 651 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 652 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 653 PROC_UNLOCK(p); 654 655 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 656 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 657 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 658 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 659 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 660 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 661 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 662 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 663 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 664 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 665 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 666 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 667 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 668 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 669 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 670 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 671 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 672 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 673 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 674 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 675 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 676 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 677 678 /* Build the argument list for the signal handler. */ 679 regs->tf_rdi = sig; /* arg 1 in %rdi */ 680 regs->tf_rax = 0; 681 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 682 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 683 684 sf.sf_handler = catcher; 685 /* Fill in POSIX parts */ 686 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 687 688 /* 689 * Copy the sigframe out to the user's stack. 690 */ 691 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 692 #ifdef DEBUG 693 printf("process %ld has trashed its stack\n", (long)p->p_pid); 694 #endif 695 PROC_LOCK(p); 696 sigexit(td, SIGILL); 697 } 698 699 regs->tf_rsp = (long)sfp; 700 regs->tf_rip = linux_rt_sigcode; 701 regs->tf_rflags &= ~(PSL_T | PSL_D); 702 regs->tf_cs = _ucodesel; 703 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 704 PROC_LOCK(p); 705 mtx_lock(&psp->ps_mtx); 706 } 707 708 /* 709 * If a linux binary is exec'ing something, try this image activator 710 * first. We override standard shell script execution in order to 711 * be able to modify the interpreter path. We only do this if a linux 712 * binary is doing the exec, so we do not create an EXEC module for it. 713 */ 714 static int exec_linux_imgact_try(struct image_params *iparams); 715 716 static int 717 exec_linux_imgact_try(struct image_params *imgp) 718 { 719 const char *head = (const char *)imgp->image_header; 720 char *rpath; 721 int error = -1, len; 722 723 /* 724 * The interpreter for shell scripts run from a linux binary needs 725 * to be located in /compat/linux if possible in order to recursively 726 * maintain linux path emulation. 727 */ 728 if (((const short *)head)[0] == SHELLMAGIC) { 729 /* 730 * Run our normal shell image activator. If it succeeds 731 * attempt to use the alternate path for the interpreter. 732 * If an alternate path is found, use our stringspace 733 * to store it. 734 */ 735 if ((error = exec_shell_imgact(imgp)) == 0) { 736 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc), 737 imgp->interpreter_name, UIO_SYSSPACE, 738 &rpath, 0, AT_FDCWD); 739 if (rpath != NULL) { 740 len = strlen(rpath) + 1; 741 742 if (len <= MAXSHELLCMDLEN) 743 memcpy(imgp->interpreter_name, 744 rpath, len); 745 free(rpath, M_TEMP); 746 } 747 } 748 } 749 return(error); 750 } 751 752 #define LINUX_VSYSCALL_START (-10UL << 20) 753 #define LINUX_VSYSCALL_SZ 1024 754 755 const unsigned long linux_vsyscall_vector[] = { 756 LINUX_SYS_gettimeofday, 757 LINUX_SYS_linux_time, 758 /* getcpu not implemented */ 759 }; 760 761 static int 762 linux_vsyscall(struct thread *td) 763 { 764 struct trapframe *frame; 765 uint64_t retqaddr; 766 int code, traced; 767 int error; 768 769 frame = td->td_frame; 770 771 /* Check %rip for vsyscall area */ 772 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 773 return (EINVAL); 774 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 775 return (EINVAL); 776 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 777 if (code >= nitems(linux_vsyscall_vector)) 778 return (EINVAL); 779 780 /* 781 * vsyscall called as callq *(%rax), so we must 782 * use return address from %rsp and also fixup %rsp 783 */ 784 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 785 if (error) 786 return (error); 787 788 frame->tf_rip = retqaddr; 789 frame->tf_rax = linux_vsyscall_vector[code]; 790 frame->tf_rsp += 8; 791 792 traced = (frame->tf_flags & PSL_T); 793 794 amd64_syscall(td, traced); 795 796 return (0); 797 } 798 799 struct sysentvec elf_linux_sysvec = { 800 .sv_size = LINUX_SYS_MAXSYSCALL, 801 .sv_table = linux_sysent, 802 .sv_mask = 0, 803 .sv_errsize = ELAST + 1, 804 .sv_errtbl = bsd_to_linux_errno, 805 .sv_transtrap = translate_traps, 806 .sv_fixup = elf_linux_fixup, 807 .sv_sendsig = linux_rt_sendsig, 808 .sv_sigcode = &_binary_linux_locore_o_start, 809 .sv_szsigcode = &linux_szsigcode, 810 .sv_name = "Linux ELF64", 811 .sv_coredump = elf64_coredump, 812 .sv_imgact_try = exec_linux_imgact_try, 813 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 814 .sv_pagesize = PAGE_SIZE, 815 .sv_minuser = VM_MIN_ADDRESS, 816 .sv_maxuser = VM_MAXUSER_ADDRESS, 817 .sv_usrstack = USRSTACK, 818 .sv_psstrings = PS_STRINGS, 819 .sv_stackprot = VM_PROT_ALL, 820 .sv_copyout_strings = linux_copyout_strings, 821 .sv_setregs = linux_exec_setregs, 822 .sv_fixlimit = NULL, 823 .sv_maxssiz = NULL, 824 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 825 .sv_set_syscall_retval = linux_set_syscall_retval, 826 .sv_fetch_syscall_args = linux_fetch_syscall_args, 827 .sv_syscallnames = NULL, 828 .sv_shared_page_base = SHAREDPAGE, 829 .sv_shared_page_len = PAGE_SIZE, 830 .sv_schedtail = linux_schedtail, 831 .sv_thread_detach = linux_thread_detach, 832 .sv_trap = linux_vsyscall, 833 }; 834 835 static void 836 linux_vdso_install(void *param) 837 { 838 839 linux_szsigcode = (&_binary_linux_locore_o_end - 840 &_binary_linux_locore_o_start); 841 842 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 843 panic("Linux invalid vdso size\n"); 844 845 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 846 847 linux_shared_page_obj = __elfN(linux_shared_page_init) 848 (&linux_shared_page_mapping); 849 850 __elfN(linux_vdso_reloc)(&elf_linux_sysvec, SHAREDPAGE); 851 852 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 853 linux_szsigcode); 854 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 855 856 linux_kplatform = linux_shared_page_mapping + 857 (linux_platform - (caddr_t)SHAREDPAGE); 858 } 859 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 860 (sysinit_cfunc_t)linux_vdso_install, NULL); 861 862 static void 863 linux_vdso_deinstall(void *param) 864 { 865 866 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 867 }; 868 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 869 (sysinit_cfunc_t)linux_vdso_deinstall, NULL); 870 871 static char GNULINUX_ABI_VENDOR[] = "GNU"; 872 static int GNULINUX_ABI_DESC = 0; 873 874 static boolean_t 875 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 876 { 877 const Elf32_Word *desc; 878 uintptr_t p; 879 880 p = (uintptr_t)(note + 1); 881 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 882 883 desc = (const Elf32_Word *)p; 884 if (desc[0] != GNULINUX_ABI_DESC) 885 return (FALSE); 886 887 /* 888 * For linux we encode osrel as follows (see linux_mib.c): 889 * VVVMMMIII (version, major, minor), see linux_mib.c. 890 */ 891 *osrel = desc[1] * 1000000 + desc[2] * 1000 + desc[3]; 892 893 return (TRUE); 894 } 895 896 static Elf_Brandnote linux64_brandnote = { 897 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 898 .hdr.n_descsz = 16, 899 .hdr.n_type = 1, 900 .vendor = GNULINUX_ABI_VENDOR, 901 .flags = BN_TRANSLATE_OSREL, 902 .trans_osrel = linux_trans_osrel 903 }; 904 905 static Elf64_Brandinfo linux_glibc2brand = { 906 .brand = ELFOSABI_LINUX, 907 .machine = EM_X86_64, 908 .compat_3_brand = "Linux", 909 .emul_path = "/compat/linux", 910 .interp_path = "/lib64/ld-linux-x86-64.so.2", 911 .sysvec = &elf_linux_sysvec, 912 .interp_newpath = NULL, 913 .brand_note = &linux64_brandnote, 914 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 915 }; 916 917 static Elf64_Brandinfo linux_glibc2brandshort = { 918 .brand = ELFOSABI_LINUX, 919 .machine = EM_X86_64, 920 .compat_3_brand = "Linux", 921 .emul_path = "/compat/linux", 922 .interp_path = "/lib64/ld-linux.so.2", 923 .sysvec = &elf_linux_sysvec, 924 .interp_newpath = NULL, 925 .brand_note = &linux64_brandnote, 926 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 927 }; 928 929 Elf64_Brandinfo *linux_brandlist[] = { 930 &linux_glibc2brand, 931 &linux_glibc2brandshort, 932 NULL 933 }; 934 935 static int 936 linux64_elf_modevent(module_t mod, int type, void *data) 937 { 938 Elf64_Brandinfo **brandinfo; 939 int error; 940 struct linux_ioctl_handler **lihp; 941 942 error = 0; 943 944 switch(type) { 945 case MOD_LOAD: 946 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 947 ++brandinfo) 948 if (elf64_insert_brand_entry(*brandinfo) < 0) 949 error = EINVAL; 950 if (error == 0) { 951 SET_FOREACH(lihp, linux_ioctl_handler_set) 952 linux_ioctl_register_handler(*lihp); 953 LIST_INIT(&futex_list); 954 mtx_init(&futex_mtx, "ftllk64", NULL, MTX_DEF); 955 stclohz = (stathz ? stathz : hz); 956 if (bootverbose) 957 printf("Linux x86-64 ELF exec handler installed\n"); 958 } else 959 printf("cannot insert Linux x86-64 ELF brand handler\n"); 960 break; 961 case MOD_UNLOAD: 962 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 963 ++brandinfo) 964 if (elf64_brand_inuse(*brandinfo)) 965 error = EBUSY; 966 if (error == 0) { 967 for (brandinfo = &linux_brandlist[0]; 968 *brandinfo != NULL; ++brandinfo) 969 if (elf64_remove_brand_entry(*brandinfo) < 0) 970 error = EINVAL; 971 } 972 if (error == 0) { 973 SET_FOREACH(lihp, linux_ioctl_handler_set) 974 linux_ioctl_unregister_handler(*lihp); 975 mtx_destroy(&futex_mtx); 976 if (bootverbose) 977 printf("Linux ELF exec handler removed\n"); 978 } else 979 printf("Could not deinstall ELF interpreter entry\n"); 980 break; 981 default: 982 return (EOPNOTSUPP); 983 } 984 return (error); 985 } 986 987 static moduledata_t linux64_elf_mod = { 988 "linux64elf", 989 linux64_elf_modevent, 990 0 991 }; 992 993 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 994 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 995