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); 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)<nitems(_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) 221 { 222 struct proc *p; 223 struct trapframe *frame; 224 struct syscall_args *sa; 225 226 p = td->td_proc; 227 frame = td->td_frame; 228 sa = &td->td_sa; 229 230 sa->args[0] = frame->tf_rdi; 231 sa->args[1] = frame->tf_rsi; 232 sa->args[2] = frame->tf_rdx; 233 sa->args[3] = frame->tf_rcx; 234 sa->args[4] = frame->tf_r8; 235 sa->args[5] = frame->tf_r9; 236 sa->code = frame->tf_rax; 237 238 if (sa->code >= p->p_sysent->sv_size) 239 /* nosys */ 240 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 241 else 242 sa->callp = &p->p_sysent->sv_table[sa->code]; 243 sa->narg = sa->callp->sy_narg; 244 245 td->td_retval[0] = 0; 246 return (0); 247 } 248 249 static void 250 linux_set_syscall_retval(struct thread *td, int error) 251 { 252 struct trapframe *frame = td->td_frame; 253 254 /* 255 * On Linux only %rcx and %r11 values are not preserved across 256 * the syscall. 257 * So, do not clobber %rdx and %r10 258 */ 259 td->td_retval[1] = frame->tf_rdx; 260 frame->tf_r10 = frame->tf_rcx; 261 262 cpu_set_syscall_retval(td, error); 263 264 /* Restore all registers. */ 265 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 266 } 267 268 static int 269 elf_linux_fixup(register_t **stack_base, struct image_params *imgp) 270 { 271 Elf_Auxargs *args; 272 Elf_Addr *base; 273 Elf_Addr *pos; 274 struct ps_strings *arginfo; 275 struct proc *p; 276 int issetugid; 277 278 p = imgp->proc; 279 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 280 281 KASSERT(curthread->td_proc == imgp->proc, 282 ("unsafe elf_linux_fixup(), should be curproc")); 283 base = (Elf64_Addr *)*stack_base; 284 args = (Elf64_Auxargs *)imgp->auxargs; 285 pos = base + (imgp->args->argc + imgp->args->envc + 2); 286 287 issetugid = p->p_flag & P_SUGID ? 1 : 0; 288 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 289 imgp->proc->p_sysent->sv_shared_page_base); 290 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 291 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 292 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 293 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 294 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 295 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 296 AUXARGS_ENTRY(pos, AT_BASE, args->base); 297 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 298 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 299 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 300 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 301 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 302 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 303 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 304 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 305 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 306 if (imgp->execpathp != 0) 307 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 308 if (args->execfd != -1) 309 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 310 AUXARGS_ENTRY(pos, AT_NULL, 0); 311 free(imgp->auxargs, M_TEMP); 312 imgp->auxargs = NULL; 313 314 base--; 315 suword(base, (uint64_t)imgp->args->argc); 316 317 *stack_base = (register_t *)base; 318 return (0); 319 } 320 321 /* 322 * Copy strings out to the new process address space, constructing new arg 323 * and env vector tables. Return a pointer to the base so that it can be used 324 * as the initial stack pointer. 325 */ 326 static register_t * 327 linux_copyout_strings(struct image_params *imgp) 328 { 329 int argc, envc; 330 char **vectp; 331 char *stringp, *destp; 332 register_t *stack_base; 333 struct ps_strings *arginfo; 334 char canary[LINUX_AT_RANDOM_LEN]; 335 size_t execpath_len; 336 struct proc *p; 337 338 /* 339 * Calculate string base and vector table pointers. 340 */ 341 if (imgp->execpath != NULL && imgp->auxargs != NULL) 342 execpath_len = strlen(imgp->execpath) + 1; 343 else 344 execpath_len = 0; 345 346 p = imgp->proc; 347 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 348 destp = (caddr_t)arginfo - SPARE_USRSPACE - 349 roundup(sizeof(canary), sizeof(char *)) - 350 roundup(execpath_len, sizeof(char *)) - 351 roundup(ARG_MAX - imgp->args->stringspace, sizeof(char *)); 352 353 if (execpath_len != 0) { 354 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 355 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 356 } 357 358 /* 359 * Prepare the canary for SSP. 360 */ 361 arc4rand(canary, sizeof(canary), 0); 362 imgp->canary = (uintptr_t)arginfo - 363 roundup(execpath_len, sizeof(char *)) - 364 roundup(sizeof(canary), sizeof(char *)); 365 copyout(canary, (void *)imgp->canary, sizeof(canary)); 366 367 /* 368 * If we have a valid auxargs ptr, prepare some room 369 * on the stack. 370 */ 371 if (imgp->auxargs) { 372 /* 373 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for 374 * lower compatibility. 375 */ 376 imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : 377 (LINUX_AT_COUNT * 2); 378 379 /* 380 * The '+ 2' is for the null pointers at the end of each of 381 * the arg and env vector sets,and imgp->auxarg_size is room 382 * for argument of Runtime loader. 383 */ 384 vectp = (char **)(destp - (imgp->args->argc + 385 imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); 386 387 } else { 388 /* 389 * The '+ 2' is for the null pointers at the end of each of 390 * the arg and env vector sets 391 */ 392 vectp = (char **)(destp - (imgp->args->argc + 393 imgp->args->envc + 2) * sizeof(char *)); 394 } 395 396 /* 397 * vectp also becomes our initial stack base 398 */ 399 stack_base = (register_t *)vectp; 400 401 stringp = imgp->args->begin_argv; 402 argc = imgp->args->argc; 403 envc = imgp->args->envc; 404 405 /* 406 * Copy out strings - arguments and environment. 407 */ 408 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 409 410 /* 411 * Fill in "ps_strings" struct for ps, w, etc. 412 */ 413 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 414 suword(&arginfo->ps_nargvstr, argc); 415 416 /* 417 * Fill in argument portion of vector table. 418 */ 419 for (; argc > 0; --argc) { 420 suword(vectp++, (long)(intptr_t)destp); 421 while (*stringp++ != 0) 422 destp++; 423 destp++; 424 } 425 426 /* a null vector table pointer separates the argp's from the envp's */ 427 suword(vectp++, 0); 428 429 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 430 suword(&arginfo->ps_nenvstr, envc); 431 432 /* 433 * Fill in environment portion of vector table. 434 */ 435 for (; envc > 0; --envc) { 436 suword(vectp++, (long)(intptr_t)destp); 437 while (*stringp++ != 0) 438 destp++; 439 destp++; 440 } 441 442 /* end of vector table is a null pointer */ 443 suword(vectp, 0); 444 return (stack_base); 445 } 446 447 /* 448 * Reset registers to default values on exec. 449 */ 450 static void 451 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 452 { 453 struct trapframe *regs = td->td_frame; 454 struct pcb *pcb = td->td_pcb; 455 456 if (td->td_proc->p_md.md_ldt != NULL) 457 user_ldt_free(td); 458 459 pcb->pcb_fsbase = 0; 460 pcb->pcb_gsbase = 0; 461 clear_pcb_flags(pcb, PCB_32BIT); 462 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 463 set_pcb_flags(pcb, PCB_FULL_IRET); 464 465 bzero((char *)regs, sizeof(struct trapframe)); 466 regs->tf_rip = imgp->entry_addr; 467 regs->tf_rsp = stack; 468 regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); 469 regs->tf_ss = _udatasel; 470 regs->tf_cs = _ucodesel; 471 regs->tf_ds = _udatasel; 472 regs->tf_es = _udatasel; 473 regs->tf_fs = _ufssel; 474 regs->tf_gs = _ugssel; 475 regs->tf_flags = TF_HASSEGS; 476 477 /* 478 * Reset the hardware debug registers if they were in use. 479 * They won't have any meaning for the newly exec'd process. 480 */ 481 if (pcb->pcb_flags & PCB_DBREGS) { 482 pcb->pcb_dr0 = 0; 483 pcb->pcb_dr1 = 0; 484 pcb->pcb_dr2 = 0; 485 pcb->pcb_dr3 = 0; 486 pcb->pcb_dr6 = 0; 487 pcb->pcb_dr7 = 0; 488 if (pcb == curpcb) { 489 /* 490 * Clear the debug registers on the running 491 * CPU, otherwise they will end up affecting 492 * the next process we switch to. 493 */ 494 reset_dbregs(); 495 } 496 clear_pcb_flags(pcb, PCB_DBREGS); 497 } 498 499 /* 500 * Drop the FP state if we hold it, so that the process gets a 501 * clean FP state if it uses the FPU again. 502 */ 503 fpstate_drop(td); 504 } 505 506 /* 507 * Copied from amd64/amd64/machdep.c 508 * 509 * XXX fpu state need? don't think so 510 */ 511 int 512 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 513 { 514 struct proc *p; 515 struct l_ucontext uc; 516 struct l_sigcontext *context; 517 struct trapframe *regs; 518 unsigned long rflags; 519 int error; 520 ksiginfo_t ksi; 521 522 regs = td->td_frame; 523 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 524 if (error != 0) 525 return (error); 526 527 p = td->td_proc; 528 context = &uc.uc_mcontext; 529 rflags = context->sc_rflags; 530 531 /* 532 * Don't allow users to change privileged or reserved flags. 533 */ 534 /* 535 * XXX do allow users to change the privileged flag PSL_RF. 536 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 537 * should sometimes set it there too. tf_rflags is kept in 538 * the signal context during signal handling and there is no 539 * other place to remember it, so the PSL_RF bit may be 540 * corrupted by the signal handler without us knowing. 541 * Corruption of the PSL_RF bit at worst causes one more or 542 * one less debugger trap, so allowing it is fairly harmless. 543 */ 544 545 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 546 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 547 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 548 return (EINVAL); 549 } 550 551 /* 552 * Don't allow users to load a valid privileged %cs. Let the 553 * hardware check for invalid selectors, excess privilege in 554 * other selectors, invalid %eip's and invalid %esp's. 555 */ 556 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 557 if (!CS_SECURE(context->sc_cs)) { 558 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 559 ksiginfo_init_trap(&ksi); 560 ksi.ksi_signo = SIGBUS; 561 ksi.ksi_code = BUS_OBJERR; 562 ksi.ksi_trapno = T_PROTFLT; 563 ksi.ksi_addr = (void *)regs->tf_rip; 564 trapsignal(td, &ksi); 565 return (EINVAL); 566 } 567 568 PROC_LOCK(p); 569 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 570 SIG_CANTMASK(td->td_sigmask); 571 signotify(td); 572 PROC_UNLOCK(p); 573 574 regs->tf_rdi = context->sc_rdi; 575 regs->tf_rsi = context->sc_rsi; 576 regs->tf_rdx = context->sc_rdx; 577 regs->tf_rbp = context->sc_rbp; 578 regs->tf_rbx = context->sc_rbx; 579 regs->tf_rcx = context->sc_rcx; 580 regs->tf_rax = context->sc_rax; 581 regs->tf_rip = context->sc_rip; 582 regs->tf_rsp = context->sc_rsp; 583 regs->tf_r8 = context->sc_r8; 584 regs->tf_r9 = context->sc_r9; 585 regs->tf_r10 = context->sc_r10; 586 regs->tf_r11 = context->sc_r11; 587 regs->tf_r12 = context->sc_r12; 588 regs->tf_r13 = context->sc_r13; 589 regs->tf_r14 = context->sc_r14; 590 regs->tf_r15 = context->sc_r15; 591 regs->tf_cs = context->sc_cs; 592 regs->tf_err = context->sc_err; 593 regs->tf_rflags = rflags; 594 595 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 596 return (EJUSTRETURN); 597 } 598 599 /* 600 * copied from amd64/amd64/machdep.c 601 * 602 * Send an interrupt to process. 603 */ 604 static void 605 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 606 { 607 struct l_rt_sigframe sf, *sfp; 608 struct proc *p; 609 struct thread *td; 610 struct sigacts *psp; 611 caddr_t sp; 612 struct trapframe *regs; 613 int sig, code; 614 int oonstack; 615 616 td = curthread; 617 p = td->td_proc; 618 PROC_LOCK_ASSERT(p, MA_OWNED); 619 sig = ksi->ksi_signo; 620 psp = p->p_sigacts; 621 code = ksi->ksi_code; 622 mtx_assert(&psp->ps_mtx, MA_OWNED); 623 regs = td->td_frame; 624 oonstack = sigonstack(regs->tf_rsp); 625 626 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 627 catcher, sig, mask, code); 628 629 /* Allocate space for the signal handler context. */ 630 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 631 SIGISMEMBER(psp->ps_sigonstack, sig)) { 632 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 633 sizeof(struct l_rt_sigframe); 634 } else 635 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 636 /* Align to 16 bytes. */ 637 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 638 mtx_unlock(&psp->ps_mtx); 639 640 /* Translate the signal. */ 641 sig = bsd_to_linux_signal(sig); 642 643 /* Save user context. */ 644 bzero(&sf, sizeof(sf)); 645 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 646 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 647 648 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 649 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 650 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 651 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 652 PROC_UNLOCK(p); 653 654 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 655 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 656 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 657 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 658 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 659 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 660 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 661 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 662 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 663 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 664 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 665 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 666 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 667 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 668 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 669 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 670 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 671 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 672 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 673 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 674 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 675 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 676 677 /* Build the argument list for the signal handler. */ 678 regs->tf_rdi = sig; /* arg 1 in %rdi */ 679 regs->tf_rax = 0; 680 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 681 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 682 683 sf.sf_handler = catcher; 684 /* Fill in POSIX parts */ 685 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 686 687 /* 688 * Copy the sigframe out to the user's stack. 689 */ 690 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 691 #ifdef DEBUG 692 printf("process %ld has trashed its stack\n", (long)p->p_pid); 693 #endif 694 PROC_LOCK(p); 695 sigexit(td, SIGILL); 696 } 697 698 regs->tf_rsp = (long)sfp; 699 regs->tf_rip = linux_rt_sigcode; 700 regs->tf_rflags &= ~(PSL_T | PSL_D); 701 regs->tf_cs = _ucodesel; 702 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 703 PROC_LOCK(p); 704 mtx_lock(&psp->ps_mtx); 705 } 706 707 /* 708 * If a linux binary is exec'ing something, try this image activator 709 * first. We override standard shell script execution in order to 710 * be able to modify the interpreter path. We only do this if a linux 711 * binary is doing the exec, so we do not create an EXEC module for it. 712 */ 713 static int exec_linux_imgact_try(struct image_params *iparams); 714 715 static int 716 exec_linux_imgact_try(struct image_params *imgp) 717 { 718 const char *head = (const char *)imgp->image_header; 719 char *rpath; 720 int error = -1; 721 722 /* 723 * The interpreter for shell scripts run from a linux binary needs 724 * to be located in /compat/linux if possible in order to recursively 725 * maintain linux path emulation. 726 */ 727 if (((const short *)head)[0] == SHELLMAGIC) { 728 /* 729 * Run our normal shell image activator. If it succeeds 730 * attempt to use the alternate path for the interpreter. 731 * If an alternate path is found, use our stringspace 732 * to store it. 733 */ 734 if ((error = exec_shell_imgact(imgp)) == 0) { 735 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc), 736 imgp->interpreter_name, UIO_SYSSPACE, 737 &rpath, 0, AT_FDCWD); 738 if (rpath != NULL) 739 imgp->args->fname_buf = 740 imgp->interpreter_name = rpath; 741 } 742 } 743 return (error); 744 } 745 746 #define LINUX_VSYSCALL_START (-10UL << 20) 747 #define LINUX_VSYSCALL_SZ 1024 748 749 const unsigned long linux_vsyscall_vector[] = { 750 LINUX_SYS_gettimeofday, 751 LINUX_SYS_linux_time, 752 /* getcpu not implemented */ 753 }; 754 755 static int 756 linux_vsyscall(struct thread *td) 757 { 758 struct trapframe *frame; 759 uint64_t retqaddr; 760 int code, traced; 761 int error; 762 763 frame = td->td_frame; 764 765 /* Check %rip for vsyscall area */ 766 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 767 return (EINVAL); 768 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 769 return (EINVAL); 770 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 771 if (code >= nitems(linux_vsyscall_vector)) 772 return (EINVAL); 773 774 /* 775 * vsyscall called as callq *(%rax), so we must 776 * use return address from %rsp and also fixup %rsp 777 */ 778 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 779 if (error) 780 return (error); 781 782 frame->tf_rip = retqaddr; 783 frame->tf_rax = linux_vsyscall_vector[code]; 784 frame->tf_rsp += 8; 785 786 traced = (frame->tf_flags & PSL_T); 787 788 amd64_syscall(td, traced); 789 790 return (0); 791 } 792 793 struct sysentvec elf_linux_sysvec = { 794 .sv_size = LINUX_SYS_MAXSYSCALL, 795 .sv_table = linux_sysent, 796 .sv_mask = 0, 797 .sv_errsize = ELAST + 1, 798 .sv_errtbl = bsd_to_linux_errno, 799 .sv_transtrap = translate_traps, 800 .sv_fixup = elf_linux_fixup, 801 .sv_sendsig = linux_rt_sendsig, 802 .sv_sigcode = &_binary_linux_locore_o_start, 803 .sv_szsigcode = &linux_szsigcode, 804 .sv_name = "Linux ELF64", 805 .sv_coredump = elf64_coredump, 806 .sv_imgact_try = exec_linux_imgact_try, 807 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 808 .sv_pagesize = PAGE_SIZE, 809 .sv_minuser = VM_MIN_ADDRESS, 810 .sv_maxuser = VM_MAXUSER_ADDRESS, 811 .sv_usrstack = USRSTACK, 812 .sv_psstrings = PS_STRINGS, 813 .sv_stackprot = VM_PROT_ALL, 814 .sv_copyout_strings = linux_copyout_strings, 815 .sv_setregs = linux_exec_setregs, 816 .sv_fixlimit = NULL, 817 .sv_maxssiz = NULL, 818 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 819 .sv_set_syscall_retval = linux_set_syscall_retval, 820 .sv_fetch_syscall_args = linux_fetch_syscall_args, 821 .sv_syscallnames = NULL, 822 .sv_shared_page_base = SHAREDPAGE, 823 .sv_shared_page_len = PAGE_SIZE, 824 .sv_schedtail = linux_schedtail, 825 .sv_thread_detach = linux_thread_detach, 826 .sv_trap = linux_vsyscall, 827 }; 828 829 static void 830 linux_vdso_install(void *param) 831 { 832 833 amd64_lower_shared_page(&elf_linux_sysvec); 834 835 linux_szsigcode = (&_binary_linux_locore_o_end - 836 &_binary_linux_locore_o_start); 837 838 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 839 panic("Linux invalid vdso size\n"); 840 841 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 842 843 linux_shared_page_obj = __elfN(linux_shared_page_init) 844 (&linux_shared_page_mapping); 845 846 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 847 848 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 849 linux_szsigcode); 850 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 851 852 linux_kplatform = linux_shared_page_mapping + 853 (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base); 854 } 855 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 856 (sysinit_cfunc_t)linux_vdso_install, NULL); 857 858 static void 859 linux_vdso_deinstall(void *param) 860 { 861 862 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 863 }; 864 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 865 (sysinit_cfunc_t)linux_vdso_deinstall, NULL); 866 867 static char GNULINUX_ABI_VENDOR[] = "GNU"; 868 static int GNULINUX_ABI_DESC = 0; 869 870 static boolean_t 871 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 872 { 873 const Elf32_Word *desc; 874 uintptr_t p; 875 876 p = (uintptr_t)(note + 1); 877 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 878 879 desc = (const Elf32_Word *)p; 880 if (desc[0] != GNULINUX_ABI_DESC) 881 return (FALSE); 882 883 /* 884 * For linux we encode osrel as follows (see linux_mib.c): 885 * VVVMMMIII (version, major, minor), see linux_mib.c. 886 */ 887 *osrel = desc[1] * 1000000 + desc[2] * 1000 + desc[3]; 888 889 return (TRUE); 890 } 891 892 static Elf_Brandnote linux64_brandnote = { 893 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 894 .hdr.n_descsz = 16, 895 .hdr.n_type = 1, 896 .vendor = GNULINUX_ABI_VENDOR, 897 .flags = BN_TRANSLATE_OSREL, 898 .trans_osrel = linux_trans_osrel 899 }; 900 901 static Elf64_Brandinfo linux_glibc2brand = { 902 .brand = ELFOSABI_LINUX, 903 .machine = EM_X86_64, 904 .compat_3_brand = "Linux", 905 .emul_path = "/compat/linux", 906 .interp_path = "/lib64/ld-linux-x86-64.so.2", 907 .sysvec = &elf_linux_sysvec, 908 .interp_newpath = NULL, 909 .brand_note = &linux64_brandnote, 910 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 911 }; 912 913 static Elf64_Brandinfo linux_glibc2brandshort = { 914 .brand = ELFOSABI_LINUX, 915 .machine = EM_X86_64, 916 .compat_3_brand = "Linux", 917 .emul_path = "/compat/linux", 918 .interp_path = "/lib64/ld-linux.so.2", 919 .sysvec = &elf_linux_sysvec, 920 .interp_newpath = NULL, 921 .brand_note = &linux64_brandnote, 922 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 923 }; 924 925 static Elf64_Brandinfo linux_muslbrand = { 926 .brand = ELFOSABI_LINUX, 927 .machine = EM_X86_64, 928 .compat_3_brand = "Linux", 929 .emul_path = "/compat/linux", 930 .interp_path = "/lib/ld-musl-x86_64.so.1", 931 .sysvec = &elf_linux_sysvec, 932 .interp_newpath = NULL, 933 .brand_note = &linux64_brandnote, 934 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 935 }; 936 937 Elf64_Brandinfo *linux_brandlist[] = { 938 &linux_glibc2brand, 939 &linux_glibc2brandshort, 940 &linux_muslbrand, 941 NULL 942 }; 943 944 static int 945 linux64_elf_modevent(module_t mod, int type, void *data) 946 { 947 Elf64_Brandinfo **brandinfo; 948 int error; 949 struct linux_ioctl_handler **lihp; 950 951 error = 0; 952 953 switch(type) { 954 case MOD_LOAD: 955 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 956 ++brandinfo) 957 if (elf64_insert_brand_entry(*brandinfo) < 0) 958 error = EINVAL; 959 if (error == 0) { 960 SET_FOREACH(lihp, linux_ioctl_handler_set) 961 linux_ioctl_register_handler(*lihp); 962 LIST_INIT(&futex_list); 963 mtx_init(&futex_mtx, "ftllk64", NULL, MTX_DEF); 964 stclohz = (stathz ? stathz : hz); 965 if (bootverbose) 966 printf("Linux x86-64 ELF exec handler installed\n"); 967 } else 968 printf("cannot insert Linux x86-64 ELF brand handler\n"); 969 break; 970 case MOD_UNLOAD: 971 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 972 ++brandinfo) 973 if (elf64_brand_inuse(*brandinfo)) 974 error = EBUSY; 975 if (error == 0) { 976 for (brandinfo = &linux_brandlist[0]; 977 *brandinfo != NULL; ++brandinfo) 978 if (elf64_remove_brand_entry(*brandinfo) < 0) 979 error = EINVAL; 980 } 981 if (error == 0) { 982 SET_FOREACH(lihp, linux_ioctl_handler_set) 983 linux_ioctl_unregister_handler(*lihp); 984 mtx_destroy(&futex_mtx); 985 if (bootverbose) 986 printf("Linux ELF exec handler removed\n"); 987 } else 988 printf("Could not deinstall ELF interpreter entry\n"); 989 break; 990 default: 991 return (EOPNOTSUPP); 992 } 993 return (error); 994 } 995 996 static moduledata_t linux64_elf_mod = { 997 "linux64elf", 998 linux64_elf_modevent, 999 0 1000 }; 1001 1002 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 1003 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 1004 FEATURE(linux64, "Linux 64bit support"); 1005