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); 132 133 /* 134 * Linux syscalls return negative errno's, we do positive and map them 135 * Reference: 136 * FreeBSD: src/sys/sys/errno.h 137 * Linux: linux-2.6.17.8/include/asm-generic/errno-base.h 138 * linux-2.6.17.8/include/asm-generic/errno.h 139 */ 140 static int bsd_to_linux_errno[ELAST + 1] = { 141 -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, 142 -10, -35, -12, -13, -14, -15, -16, -17, -18, -19, 143 -20, -21, -22, -23, -24, -25, -26, -27, -28, -29, 144 -30, -31, -32, -33, -34, -11,-115,-114, -88, -89, 145 -90, -91, -92, -93, -94, -95, -96, -97, -98, -99, 146 -100,-101,-102,-103,-104,-105,-106,-107,-108,-109, 147 -110,-111, -40, -36,-112,-113, -39, -11, -87,-122, 148 -116, -66, -6, -6, -6, -6, -6, -37, -38, -9, 149 -6, -6, -43, -42, -75,-125, -84, -95, -16, -74, 150 -72, -67, -71 151 }; 152 153 #define LINUX_T_UNKNOWN 255 154 static int _bsd_to_linux_trapcode[] = { 155 LINUX_T_UNKNOWN, /* 0 */ 156 6, /* 1 T_PRIVINFLT */ 157 LINUX_T_UNKNOWN, /* 2 */ 158 3, /* 3 T_BPTFLT */ 159 LINUX_T_UNKNOWN, /* 4 */ 160 LINUX_T_UNKNOWN, /* 5 */ 161 16, /* 6 T_ARITHTRAP */ 162 254, /* 7 T_ASTFLT */ 163 LINUX_T_UNKNOWN, /* 8 */ 164 13, /* 9 T_PROTFLT */ 165 1, /* 10 T_TRCTRAP */ 166 LINUX_T_UNKNOWN, /* 11 */ 167 14, /* 12 T_PAGEFLT */ 168 LINUX_T_UNKNOWN, /* 13 */ 169 17, /* 14 T_ALIGNFLT */ 170 LINUX_T_UNKNOWN, /* 15 */ 171 LINUX_T_UNKNOWN, /* 16 */ 172 LINUX_T_UNKNOWN, /* 17 */ 173 0, /* 18 T_DIVIDE */ 174 2, /* 19 T_NMI */ 175 4, /* 20 T_OFLOW */ 176 5, /* 21 T_BOUND */ 177 7, /* 22 T_DNA */ 178 8, /* 23 T_DOUBLEFLT */ 179 9, /* 24 T_FPOPFLT */ 180 10, /* 25 T_TSSFLT */ 181 11, /* 26 T_SEGNPFLT */ 182 12, /* 27 T_STKFLT */ 183 18, /* 28 T_MCHK */ 184 19, /* 29 T_XMMFLT */ 185 15 /* 30 T_RESERVED */ 186 }; 187 #define bsd_to_linux_trapcode(code) \ 188 ((code)<sizeof(_bsd_to_linux_trapcode)/sizeof(*_bsd_to_linux_trapcode)? \ 189 _bsd_to_linux_trapcode[(code)]: \ 190 LINUX_T_UNKNOWN) 191 192 LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 193 LINUX_VDSO_SYM_CHAR(linux_platform); 194 195 /* 196 * If FreeBSD & Linux have a difference of opinion about what a trap 197 * means, deal with it here. 198 * 199 * MPSAFE 200 */ 201 static int 202 translate_traps(int signal, int trap_code) 203 { 204 205 if (signal != SIGBUS) 206 return signal; 207 switch (trap_code) { 208 case T_PROTFLT: 209 case T_TSSFLT: 210 case T_DOUBLEFLT: 211 case T_PAGEFLT: 212 return SIGSEGV; 213 default: 214 return signal; 215 } 216 } 217 218 static int 219 linux_fetch_syscall_args(struct thread *td, struct syscall_args *sa) 220 { 221 struct proc *p; 222 struct trapframe *frame; 223 224 p = td->td_proc; 225 frame = td->td_frame; 226 227 sa->args[0] = frame->tf_rdi; 228 sa->args[1] = frame->tf_rsi; 229 sa->args[2] = frame->tf_rdx; 230 sa->args[3] = frame->tf_rcx; 231 sa->args[4] = frame->tf_r8; 232 sa->args[5] = frame->tf_r9; 233 sa->code = frame->tf_rax; 234 235 if (sa->code >= p->p_sysent->sv_size) 236 /* nosys */ 237 sa->callp = &p->p_sysent->sv_table[LINUX_SYS_MAXSYSCALL]; 238 else 239 sa->callp = &p->p_sysent->sv_table[sa->code]; 240 sa->narg = sa->callp->sy_narg; 241 242 td->td_retval[0] = 0; 243 return (0); 244 } 245 246 static void 247 linux_set_syscall_retval(struct thread *td, int error) 248 { 249 struct trapframe *frame = td->td_frame; 250 251 /* 252 * On Linux only %rcx and %r11 values are not preserved across 253 * the syscall. 254 * So, do not clobber %rdx and %r10 255 */ 256 td->td_retval[1] = frame->tf_rdx; 257 frame->tf_r10 = frame->tf_rcx; 258 259 cpu_set_syscall_retval(td, error); 260 261 /* Restore all registers. */ 262 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 263 } 264 265 static int 266 elf_linux_fixup(register_t **stack_base, struct image_params *imgp) 267 { 268 Elf_Auxargs *args; 269 Elf_Addr *base; 270 Elf_Addr *pos; 271 struct ps_strings *arginfo; 272 struct proc *p; 273 274 p = imgp->proc; 275 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 276 277 KASSERT(curthread->td_proc == imgp->proc, 278 ("unsafe elf_linux_fixup(), should be curproc")); 279 base = (Elf64_Addr *)*stack_base; 280 args = (Elf64_Auxargs *)imgp->auxargs; 281 pos = base + (imgp->args->argc + imgp->args->envc + 2); 282 283 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 284 imgp->proc->p_sysent->sv_shared_page_base); 285 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 286 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 287 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 288 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 289 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 290 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 291 AUXARGS_ENTRY(pos, AT_BASE, args->base); 292 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 293 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 294 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 295 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 296 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 297 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 298 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, 0); 299 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 300 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 301 if (imgp->execpathp != 0) 302 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 303 if (args->execfd != -1) 304 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 305 AUXARGS_ENTRY(pos, AT_NULL, 0); 306 free(imgp->auxargs, M_TEMP); 307 imgp->auxargs = NULL; 308 309 base--; 310 suword(base, (uint64_t)imgp->args->argc); 311 312 *stack_base = (register_t *)base; 313 return (0); 314 } 315 316 /* 317 * Copy strings out to the new process address space, constructing new arg 318 * and env vector tables. Return a pointer to the base so that it can be used 319 * as the initial stack pointer. 320 */ 321 static register_t * 322 linux_copyout_strings(struct image_params *imgp) 323 { 324 int argc, envc; 325 char **vectp; 326 char *stringp, *destp; 327 register_t *stack_base; 328 struct ps_strings *arginfo; 329 char canary[LINUX_AT_RANDOM_LEN]; 330 size_t execpath_len; 331 struct proc *p; 332 333 /* 334 * Calculate string base and vector table pointers. 335 */ 336 if (imgp->execpath != NULL && imgp->auxargs != NULL) 337 execpath_len = strlen(imgp->execpath) + 1; 338 else 339 execpath_len = 0; 340 341 p = imgp->proc; 342 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 343 destp = (caddr_t)arginfo - SPARE_USRSPACE - 344 roundup(sizeof(canary), sizeof(char *)) - 345 roundup(execpath_len, sizeof(char *)) - 346 roundup((ARG_MAX - imgp->args->stringspace), sizeof(char *)); 347 348 if (execpath_len != 0) { 349 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 350 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 351 } 352 353 /* 354 * Prepare the canary for SSP. 355 */ 356 arc4rand(canary, sizeof(canary), 0); 357 imgp->canary = (uintptr_t)arginfo - 358 roundup(execpath_len, sizeof(char *)) - 359 roundup(sizeof(canary), sizeof(char *)); 360 copyout(canary, (void *)imgp->canary, sizeof(canary)); 361 362 /* 363 * If we have a valid auxargs ptr, prepare some room 364 * on the stack. 365 */ 366 if (imgp->auxargs) { 367 /* 368 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for 369 * lower compatibility. 370 */ 371 imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : 372 (LINUX_AT_COUNT * 2); 373 374 /* 375 * The '+ 2' is for the null pointers at the end of each of 376 * the arg and env vector sets,and imgp->auxarg_size is room 377 * for argument of Runtime loader. 378 */ 379 vectp = (char **)(destp - (imgp->args->argc + 380 imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); 381 382 } else { 383 /* 384 * The '+ 2' is for the null pointers at the end of each of 385 * the arg and env vector sets 386 */ 387 vectp = (char **)(destp - (imgp->args->argc + 388 imgp->args->envc + 2) * sizeof(char *)); 389 } 390 391 /* 392 * vectp also becomes our initial stack base 393 */ 394 stack_base = (register_t *)vectp; 395 396 stringp = imgp->args->begin_argv; 397 argc = imgp->args->argc; 398 envc = imgp->args->envc; 399 400 /* 401 * Copy out strings - arguments and environment. 402 */ 403 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 404 405 /* 406 * Fill in "ps_strings" struct for ps, w, etc. 407 */ 408 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 409 suword(&arginfo->ps_nargvstr, argc); 410 411 /* 412 * Fill in argument portion of vector table. 413 */ 414 for (; argc > 0; --argc) { 415 suword(vectp++, (long)(intptr_t)destp); 416 while (*stringp++ != 0) 417 destp++; 418 destp++; 419 } 420 421 /* a null vector table pointer separates the argp's from the envp's */ 422 suword(vectp++, 0); 423 424 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 425 suword(&arginfo->ps_nenvstr, envc); 426 427 /* 428 * Fill in environment portion of vector table. 429 */ 430 for (; envc > 0; --envc) { 431 suword(vectp++, (long)(intptr_t)destp); 432 while (*stringp++ != 0) 433 destp++; 434 destp++; 435 } 436 437 /* end of vector table is a null pointer */ 438 suword(vectp, 0); 439 return (stack_base); 440 } 441 442 /* 443 * Reset registers to default values on exec. 444 */ 445 static void 446 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 447 { 448 struct trapframe *regs = td->td_frame; 449 struct pcb *pcb = td->td_pcb; 450 451 mtx_lock(&dt_lock); 452 if (td->td_proc->p_md.md_ldt != NULL) 453 user_ldt_free(td); 454 else 455 mtx_unlock(&dt_lock); 456 457 pcb->pcb_fsbase = 0; 458 pcb->pcb_gsbase = 0; 459 clear_pcb_flags(pcb, PCB_32BIT); 460 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 461 set_pcb_flags(pcb, PCB_FULL_IRET); 462 463 bzero((char *)regs, sizeof(struct trapframe)); 464 regs->tf_rip = imgp->entry_addr; 465 regs->tf_rsp = stack; 466 regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); 467 regs->tf_ss = _udatasel; 468 regs->tf_cs = _ucodesel; 469 regs->tf_ds = _udatasel; 470 regs->tf_es = _udatasel; 471 regs->tf_fs = _ufssel; 472 regs->tf_gs = _ugssel; 473 regs->tf_flags = TF_HASSEGS; 474 475 /* 476 * Reset the hardware debug registers if they were in use. 477 * They won't have any meaning for the newly exec'd process. 478 */ 479 if (pcb->pcb_flags & PCB_DBREGS) { 480 pcb->pcb_dr0 = 0; 481 pcb->pcb_dr1 = 0; 482 pcb->pcb_dr2 = 0; 483 pcb->pcb_dr3 = 0; 484 pcb->pcb_dr6 = 0; 485 pcb->pcb_dr7 = 0; 486 if (pcb == curpcb) { 487 /* 488 * Clear the debug registers on the running 489 * CPU, otherwise they will end up affecting 490 * the next process we switch to. 491 */ 492 reset_dbregs(); 493 } 494 clear_pcb_flags(pcb, PCB_DBREGS); 495 } 496 497 /* 498 * Drop the FP state if we hold it, so that the process gets a 499 * clean FP state if it uses the FPU again. 500 */ 501 fpstate_drop(td); 502 } 503 504 /* 505 * Copied from amd64/amd64/machdep.c 506 * 507 * XXX fpu state need? don't think so 508 */ 509 int 510 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 511 { 512 struct proc *p; 513 struct l_ucontext uc; 514 struct l_sigcontext *context; 515 struct trapframe *regs; 516 unsigned long rflags; 517 int error; 518 ksiginfo_t ksi; 519 520 regs = td->td_frame; 521 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 522 if (error != 0) 523 return (error); 524 525 p = td->td_proc; 526 context = &uc.uc_mcontext; 527 rflags = context->sc_rflags; 528 529 /* 530 * Don't allow users to change privileged or reserved flags. 531 */ 532 /* 533 * XXX do allow users to change the privileged flag PSL_RF. 534 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 535 * should sometimes set it there too. tf_rflags is kept in 536 * the signal context during signal handling and there is no 537 * other place to remember it, so the PSL_RF bit may be 538 * corrupted by the signal handler without us knowing. 539 * Corruption of the PSL_RF bit at worst causes one more or 540 * one less debugger trap, so allowing it is fairly harmless. 541 */ 542 543 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 544 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 545 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 546 return (EINVAL); 547 } 548 549 /* 550 * Don't allow users to load a valid privileged %cs. Let the 551 * hardware check for invalid selectors, excess privilege in 552 * other selectors, invalid %eip's and invalid %esp's. 553 */ 554 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 555 if (!CS_SECURE(context->sc_cs)) { 556 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 557 ksiginfo_init_trap(&ksi); 558 ksi.ksi_signo = SIGBUS; 559 ksi.ksi_code = BUS_OBJERR; 560 ksi.ksi_trapno = T_PROTFLT; 561 ksi.ksi_addr = (void *)regs->tf_rip; 562 trapsignal(td, &ksi); 563 return (EINVAL); 564 } 565 566 PROC_LOCK(p); 567 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 568 SIG_CANTMASK(td->td_sigmask); 569 signotify(td); 570 PROC_UNLOCK(p); 571 572 regs->tf_rdi = context->sc_rdi; 573 regs->tf_rsi = context->sc_rsi; 574 regs->tf_rdx = context->sc_rdx; 575 regs->tf_rbp = context->sc_rbp; 576 regs->tf_rbx = context->sc_rbx; 577 regs->tf_rcx = context->sc_rcx; 578 regs->tf_rax = context->sc_rax; 579 regs->tf_rip = context->sc_rip; 580 regs->tf_rsp = context->sc_rsp; 581 regs->tf_r8 = context->sc_r8; 582 regs->tf_r9 = context->sc_r9; 583 regs->tf_r10 = context->sc_r10; 584 regs->tf_r11 = context->sc_r11; 585 regs->tf_r12 = context->sc_r12; 586 regs->tf_r13 = context->sc_r13; 587 regs->tf_r14 = context->sc_r14; 588 regs->tf_r15 = context->sc_r15; 589 regs->tf_cs = context->sc_cs; 590 regs->tf_err = context->sc_err; 591 regs->tf_rflags = rflags; 592 593 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 594 return (EJUSTRETURN); 595 } 596 597 /* 598 * copied from amd64/amd64/machdep.c 599 * 600 * Send an interrupt to process. 601 */ 602 static void 603 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 604 { 605 struct l_rt_sigframe sf, *sfp; 606 struct proc *p; 607 struct thread *td; 608 struct sigacts *psp; 609 caddr_t sp; 610 struct trapframe *regs; 611 int sig, code; 612 int oonstack; 613 614 td = curthread; 615 p = td->td_proc; 616 PROC_LOCK_ASSERT(p, MA_OWNED); 617 sig = ksi->ksi_signo; 618 psp = p->p_sigacts; 619 code = ksi->ksi_code; 620 mtx_assert(&psp->ps_mtx, MA_OWNED); 621 regs = td->td_frame; 622 oonstack = sigonstack(regs->tf_rsp); 623 624 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 625 catcher, sig, mask, code); 626 627 /* Allocate space for the signal handler context. */ 628 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 629 SIGISMEMBER(psp->ps_sigonstack, sig)) { 630 sp = td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 631 sizeof(struct l_rt_sigframe); 632 } else 633 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 634 /* Align to 16 bytes. */ 635 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 636 mtx_unlock(&psp->ps_mtx); 637 638 /* Translate the signal. */ 639 sig = bsd_to_linux_signal(sig); 640 641 /* Save user context. */ 642 bzero(&sf, sizeof(sf)); 643 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 644 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 645 646 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 647 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 648 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 649 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 650 PROC_UNLOCK(p); 651 652 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 653 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 654 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 655 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 656 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 657 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 658 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 659 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 660 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 661 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 662 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 663 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 664 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 665 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 666 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 667 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 668 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 669 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 670 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 671 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 672 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 673 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 674 675 /* Build the argument list for the signal handler. */ 676 regs->tf_rdi = sig; /* arg 1 in %rdi */ 677 regs->tf_rax = 0; 678 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 679 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 680 681 sf.sf_handler = catcher; 682 /* Fill in POSIX parts */ 683 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 684 685 /* 686 * Copy the sigframe out to the user's stack. 687 */ 688 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 689 #ifdef DEBUG 690 printf("process %ld has trashed its stack\n", (long)p->p_pid); 691 #endif 692 PROC_LOCK(p); 693 sigexit(td, SIGILL); 694 } 695 696 regs->tf_rsp = (long)sfp; 697 regs->tf_rip = linux_rt_sigcode; 698 regs->tf_rflags &= ~(PSL_T | PSL_D); 699 regs->tf_cs = _ucodesel; 700 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 701 PROC_LOCK(p); 702 mtx_lock(&psp->ps_mtx); 703 } 704 705 /* 706 * If a linux binary is exec'ing something, try this image activator 707 * first. We override standard shell script execution in order to 708 * be able to modify the interpreter path. We only do this if a linux 709 * binary is doing the exec, so we do not create an EXEC module for it. 710 */ 711 static int exec_linux_imgact_try(struct image_params *iparams); 712 713 static int 714 exec_linux_imgact_try(struct image_params *imgp) 715 { 716 const char *head = (const char *)imgp->image_header; 717 char *rpath; 718 int error = -1, len; 719 720 /* 721 * The interpreter for shell scripts run from a linux binary needs 722 * to be located in /compat/linux if possible in order to recursively 723 * maintain linux path emulation. 724 */ 725 if (((const short *)head)[0] == SHELLMAGIC) { 726 /* 727 * Run our normal shell image activator. If it succeeds 728 * attempt to use the alternate path for the interpreter. 729 * If an alternate path is found, use our stringspace 730 * to store it. 731 */ 732 if ((error = exec_shell_imgact(imgp)) == 0) { 733 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc), 734 imgp->interpreter_name, UIO_SYSSPACE, 735 &rpath, 0, AT_FDCWD); 736 if (rpath != NULL) { 737 len = strlen(rpath) + 1; 738 739 if (len <= MAXSHELLCMDLEN) 740 memcpy(imgp->interpreter_name, 741 rpath, len); 742 free(rpath, M_TEMP); 743 } 744 } 745 } 746 return(error); 747 } 748 749 struct sysentvec elf_linux_sysvec = { 750 .sv_size = LINUX_SYS_MAXSYSCALL, 751 .sv_table = linux_sysent, 752 .sv_mask = 0, 753 .sv_sigsize = 0, 754 .sv_sigtbl = NULL, 755 .sv_errsize = ELAST + 1, 756 .sv_errtbl = bsd_to_linux_errno, 757 .sv_transtrap = translate_traps, 758 .sv_fixup = elf_linux_fixup, 759 .sv_sendsig = linux_rt_sendsig, 760 .sv_sigcode = &_binary_linux_locore_o_start, 761 .sv_szsigcode = &linux_szsigcode, 762 .sv_prepsyscall = NULL, 763 .sv_name = "Linux ELF64", 764 .sv_coredump = elf64_coredump, 765 .sv_imgact_try = exec_linux_imgact_try, 766 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 767 .sv_pagesize = PAGE_SIZE, 768 .sv_minuser = VM_MIN_ADDRESS, 769 .sv_maxuser = VM_MAXUSER_ADDRESS, 770 .sv_usrstack = USRSTACK, 771 .sv_psstrings = PS_STRINGS, 772 .sv_stackprot = VM_PROT_ALL, 773 .sv_copyout_strings = linux_copyout_strings, 774 .sv_setregs = linux_exec_setregs, 775 .sv_fixlimit = NULL, 776 .sv_maxssiz = NULL, 777 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 778 .sv_set_syscall_retval = linux_set_syscall_retval, 779 .sv_fetch_syscall_args = linux_fetch_syscall_args, 780 .sv_syscallnames = NULL, 781 .sv_shared_page_base = SHAREDPAGE, 782 .sv_shared_page_len = PAGE_SIZE, 783 .sv_schedtail = linux_schedtail, 784 .sv_thread_detach = linux_thread_detach 785 }; 786 787 static void 788 linux_vdso_install(void *param) 789 { 790 791 linux_szsigcode = (&_binary_linux_locore_o_end - 792 &_binary_linux_locore_o_start); 793 794 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 795 panic("Linux invalid vdso size\n"); 796 797 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 798 799 linux_shared_page_obj = __elfN(linux_shared_page_init) 800 (&linux_shared_page_mapping); 801 802 __elfN(linux_vdso_reloc)(&elf_linux_sysvec, SHAREDPAGE); 803 804 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 805 linux_szsigcode); 806 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 807 808 linux_kplatform = linux_shared_page_mapping + 809 (linux_platform - (caddr_t)SHAREDPAGE); 810 } 811 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 812 (sysinit_cfunc_t)linux_vdso_install, NULL); 813 814 static void 815 linux_vdso_deinstall(void *param) 816 { 817 818 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 819 }; 820 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 821 (sysinit_cfunc_t)linux_vdso_deinstall, NULL); 822 823 static char GNULINUX_ABI_VENDOR[] = "GNU"; 824 static int GNULINUX_ABI_DESC = 0; 825 826 static boolean_t 827 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 828 { 829 const Elf32_Word *desc; 830 uintptr_t p; 831 832 p = (uintptr_t)(note + 1); 833 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 834 835 desc = (const Elf32_Word *)p; 836 if (desc[0] != GNULINUX_ABI_DESC) 837 return (FALSE); 838 839 /* 840 * For linux we encode osrel as follows (see linux_mib.c): 841 * VVVMMMIII (version, major, minor), see linux_mib.c. 842 */ 843 *osrel = desc[1] * 1000000 + desc[2] * 1000 + desc[3]; 844 845 return (TRUE); 846 } 847 848 static Elf_Brandnote linux64_brandnote = { 849 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 850 .hdr.n_descsz = 16, 851 .hdr.n_type = 1, 852 .vendor = GNULINUX_ABI_VENDOR, 853 .flags = BN_TRANSLATE_OSREL, 854 .trans_osrel = linux_trans_osrel 855 }; 856 857 static Elf64_Brandinfo linux_glibc2brand = { 858 .brand = ELFOSABI_LINUX, 859 .machine = EM_X86_64, 860 .compat_3_brand = "Linux", 861 .emul_path = "/compat/linux", 862 .interp_path = "/lib64/ld-linux-x86-64.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_glibc2brandshort = { 870 .brand = ELFOSABI_LINUX, 871 .machine = EM_X86_64, 872 .compat_3_brand = "Linux", 873 .emul_path = "/compat/linux", 874 .interp_path = "/lib64/ld-linux.so.2", 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 NULL 885 }; 886 887 static int 888 linux64_elf_modevent(module_t mod, int type, void *data) 889 { 890 Elf64_Brandinfo **brandinfo; 891 int error; 892 struct linux_ioctl_handler **lihp; 893 894 error = 0; 895 896 switch(type) { 897 case MOD_LOAD: 898 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 899 ++brandinfo) 900 if (elf64_insert_brand_entry(*brandinfo) < 0) 901 error = EINVAL; 902 if (error == 0) { 903 SET_FOREACH(lihp, linux_ioctl_handler_set) 904 linux_ioctl_register_handler(*lihp); 905 LIST_INIT(&futex_list); 906 mtx_init(&futex_mtx, "ftllk64", NULL, MTX_DEF); 907 stclohz = (stathz ? stathz : hz); 908 if (bootverbose) 909 printf("Linux x86-64 ELF exec handler installed\n"); 910 } else 911 printf("cannot insert Linux x86-64 ELF brand handler\n"); 912 break; 913 case MOD_UNLOAD: 914 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 915 ++brandinfo) 916 if (elf64_brand_inuse(*brandinfo)) 917 error = EBUSY; 918 if (error == 0) { 919 for (brandinfo = &linux_brandlist[0]; 920 *brandinfo != NULL; ++brandinfo) 921 if (elf64_remove_brand_entry(*brandinfo) < 0) 922 error = EINVAL; 923 } 924 if (error == 0) { 925 SET_FOREACH(lihp, linux_ioctl_handler_set) 926 linux_ioctl_unregister_handler(*lihp); 927 mtx_destroy(&futex_mtx); 928 if (bootverbose) 929 printf("Linux ELF exec handler removed\n"); 930 } else 931 printf("Could not deinstall ELF interpreter entry\n"); 932 break; 933 default: 934 return (EOPNOTSUPP); 935 } 936 return (error); 937 } 938 939 static moduledata_t linux64_elf_mod = { 940 "linux64elf", 941 linux64_elf_modevent, 942 0 943 }; 944 945 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 946 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 947