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 sendsig functions to use the ldebug() facility even though they 105 * are not syscalls themselves. Map them to syscall 0. This is slightly less 106 * bogus than using ldebug(sigreturn). 107 */ 108 #define LINUX_SYS_linux_rt_sendsig 0 109 110 const char *linux_kplatform; 111 static int linux_szsigcode; 112 static vm_object_t linux_shared_page_obj; 113 static char *linux_shared_page_mapping; 114 extern char _binary_linux_locore_o_start; 115 extern char _binary_linux_locore_o_end; 116 117 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 118 119 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 120 121 static register_t * linux_copyout_strings(struct image_params *imgp); 122 static int linux_fixup_elf(register_t **stack_base, 123 struct image_params *iparams); 124 static bool linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 125 static void linux_vdso_install(void *param); 126 static void linux_vdso_deinstall(void *param); 127 static void linux_set_syscall_retval(struct thread *td, int error); 128 static int linux_fetch_syscall_args(struct thread *td); 129 static int linux_exec_imgact_try(struct image_params *iparams); 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 #define LINUX_T_UNKNOWN 255 135 static int _bsd_to_linux_trapcode[] = { 136 LINUX_T_UNKNOWN, /* 0 */ 137 6, /* 1 T_PRIVINFLT */ 138 LINUX_T_UNKNOWN, /* 2 */ 139 3, /* 3 T_BPTFLT */ 140 LINUX_T_UNKNOWN, /* 4 */ 141 LINUX_T_UNKNOWN, /* 5 */ 142 16, /* 6 T_ARITHTRAP */ 143 254, /* 7 T_ASTFLT */ 144 LINUX_T_UNKNOWN, /* 8 */ 145 13, /* 9 T_PROTFLT */ 146 1, /* 10 T_TRCTRAP */ 147 LINUX_T_UNKNOWN, /* 11 */ 148 14, /* 12 T_PAGEFLT */ 149 LINUX_T_UNKNOWN, /* 13 */ 150 17, /* 14 T_ALIGNFLT */ 151 LINUX_T_UNKNOWN, /* 15 */ 152 LINUX_T_UNKNOWN, /* 16 */ 153 LINUX_T_UNKNOWN, /* 17 */ 154 0, /* 18 T_DIVIDE */ 155 2, /* 19 T_NMI */ 156 4, /* 20 T_OFLOW */ 157 5, /* 21 T_BOUND */ 158 7, /* 22 T_DNA */ 159 8, /* 23 T_DOUBLEFLT */ 160 9, /* 24 T_FPOPFLT */ 161 10, /* 25 T_TSSFLT */ 162 11, /* 26 T_SEGNPFLT */ 163 12, /* 27 T_STKFLT */ 164 18, /* 28 T_MCHK */ 165 19, /* 29 T_XMMFLT */ 166 15 /* 30 T_RESERVED */ 167 }; 168 #define bsd_to_linux_trapcode(code) \ 169 ((code)<nitems(_bsd_to_linux_trapcode)? \ 170 _bsd_to_linux_trapcode[(code)]: \ 171 LINUX_T_UNKNOWN) 172 173 LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 174 LINUX_VDSO_SYM_CHAR(linux_platform); 175 176 /* 177 * If FreeBSD & Linux have a difference of opinion about what a trap 178 * means, deal with it here. 179 * 180 * MPSAFE 181 */ 182 static int 183 linux_translate_traps(int signal, int trap_code) 184 { 185 186 if (signal != SIGBUS) 187 return signal; 188 switch (trap_code) { 189 case T_PROTFLT: 190 case T_TSSFLT: 191 case T_DOUBLEFLT: 192 case T_PAGEFLT: 193 return SIGSEGV; 194 default: 195 return signal; 196 } 197 } 198 199 static int 200 linux_fetch_syscall_args(struct thread *td) 201 { 202 struct proc *p; 203 struct trapframe *frame; 204 struct syscall_args *sa; 205 206 p = td->td_proc; 207 frame = td->td_frame; 208 sa = &td->td_sa; 209 210 sa->args[0] = frame->tf_rdi; 211 sa->args[1] = frame->tf_rsi; 212 sa->args[2] = frame->tf_rdx; 213 sa->args[3] = frame->tf_rcx; 214 sa->args[4] = frame->tf_r8; 215 sa->args[5] = frame->tf_r9; 216 sa->code = frame->tf_rax; 217 218 if (sa->code >= p->p_sysent->sv_size) 219 /* nosys */ 220 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 221 else 222 sa->callp = &p->p_sysent->sv_table[sa->code]; 223 sa->narg = sa->callp->sy_narg; 224 225 td->td_retval[0] = 0; 226 return (0); 227 } 228 229 static void 230 linux_set_syscall_retval(struct thread *td, int error) 231 { 232 struct trapframe *frame = td->td_frame; 233 234 /* 235 * On Linux only %rcx and %r11 values are not preserved across 236 * the syscall. So, do not clobber %rdx and %r10. 237 */ 238 td->td_retval[1] = frame->tf_rdx; 239 frame->tf_r10 = frame->tf_rcx; 240 241 cpu_set_syscall_retval(td, error); 242 243 /* Restore all registers. */ 244 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 245 } 246 247 static int 248 linux_fixup_elf(register_t **stack_base, struct image_params *imgp) 249 { 250 Elf_Auxargs *args; 251 Elf_Addr *base; 252 Elf_Addr *pos; 253 struct ps_strings *arginfo; 254 struct proc *p; 255 int issetugid; 256 257 p = imgp->proc; 258 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 259 260 KASSERT(curthread->td_proc == imgp->proc, 261 ("unsafe linux_fixup_elf(), should be curproc")); 262 base = (Elf64_Addr *)*stack_base; 263 args = (Elf64_Auxargs *)imgp->auxargs; 264 pos = base + (imgp->args->argc + imgp->args->envc + 2); 265 266 issetugid = p->p_flag & P_SUGID ? 1 : 0; 267 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 268 imgp->proc->p_sysent->sv_shared_page_base); 269 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 270 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 271 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 272 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 273 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 274 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 275 AUXARGS_ENTRY(pos, AT_BASE, args->base); 276 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 277 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 278 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 279 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 280 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 281 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 282 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 283 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 284 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 285 if (imgp->execpathp != 0) 286 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 287 if (args->execfd != -1) 288 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 289 AUXARGS_ENTRY(pos, AT_NULL, 0); 290 free(imgp->auxargs, M_TEMP); 291 imgp->auxargs = NULL; 292 293 base--; 294 suword(base, (uint64_t)imgp->args->argc); 295 296 *stack_base = (register_t *)base; 297 return (0); 298 } 299 300 /* 301 * Copy strings out to the new process address space, constructing new arg 302 * and env vector tables. Return a pointer to the base so that it can be used 303 * as the initial stack pointer. 304 */ 305 static register_t * 306 linux_copyout_strings(struct image_params *imgp) 307 { 308 int argc, envc; 309 char **vectp; 310 char *stringp, *destp; 311 register_t *stack_base; 312 struct ps_strings *arginfo; 313 char canary[LINUX_AT_RANDOM_LEN]; 314 size_t execpath_len; 315 struct proc *p; 316 317 /* Calculate string base and vector table pointers. */ 318 if (imgp->execpath != NULL && imgp->auxargs != NULL) 319 execpath_len = strlen(imgp->execpath) + 1; 320 else 321 execpath_len = 0; 322 323 p = imgp->proc; 324 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 325 destp = (caddr_t)arginfo - SPARE_USRSPACE - 326 roundup(sizeof(canary), sizeof(char *)) - 327 roundup(execpath_len, sizeof(char *)) - 328 roundup(ARG_MAX - imgp->args->stringspace, sizeof(char *)); 329 330 if (execpath_len != 0) { 331 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 332 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 333 } 334 335 /* Prepare the canary for SSP. */ 336 arc4rand(canary, sizeof(canary), 0); 337 imgp->canary = (uintptr_t)arginfo - 338 roundup(execpath_len, sizeof(char *)) - 339 roundup(sizeof(canary), sizeof(char *)); 340 copyout(canary, (void *)imgp->canary, sizeof(canary)); 341 342 /* If we have a valid auxargs ptr, prepare some room on the stack. */ 343 if (imgp->auxargs) { 344 /* 345 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for 346 * lower compatibility. 347 */ 348 imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : 349 (LINUX_AT_COUNT * 2); 350 351 /* 352 * The '+ 2' is for the null pointers at the end of each of 353 * the arg and env vector sets,and imgp->auxarg_size is room 354 * for argument of Runtime loader. 355 */ 356 vectp = (char **)(destp - (imgp->args->argc + 357 imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); 358 359 } else { 360 /* 361 * The '+ 2' is for the null pointers at the end of each of 362 * the arg and env vector sets 363 */ 364 vectp = (char **)(destp - (imgp->args->argc + 365 imgp->args->envc + 2) * sizeof(char *)); 366 } 367 368 /* vectp also becomes our initial stack base. */ 369 stack_base = (register_t *)vectp; 370 371 stringp = imgp->args->begin_argv; 372 argc = imgp->args->argc; 373 envc = imgp->args->envc; 374 375 /* Copy out strings - arguments and environment. */ 376 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 377 378 /* Fill in "ps_strings" struct for ps, w, etc. */ 379 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 380 suword(&arginfo->ps_nargvstr, argc); 381 382 /* Fill in argument portion of vector table. */ 383 for (; argc > 0; --argc) { 384 suword(vectp++, (long)(intptr_t)destp); 385 while (*stringp++ != 0) 386 destp++; 387 destp++; 388 } 389 390 /* A null vector table pointer separates the argp's from the envp's. */ 391 suword(vectp++, 0); 392 393 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 394 suword(&arginfo->ps_nenvstr, envc); 395 396 /* Fill in environment portion of vector table. */ 397 for (; envc > 0; --envc) { 398 suword(vectp++, (long)(intptr_t)destp); 399 while (*stringp++ != 0) 400 destp++; 401 destp++; 402 } 403 404 /* The end of the vector table is a null pointer. */ 405 suword(vectp, 0); 406 return (stack_base); 407 } 408 409 /* 410 * Reset registers to default values on exec. 411 */ 412 static void 413 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 414 { 415 struct trapframe *regs = td->td_frame; 416 struct pcb *pcb = td->td_pcb; 417 418 if (td->td_proc->p_md.md_ldt != NULL) 419 user_ldt_free(td); 420 421 pcb->pcb_fsbase = 0; 422 pcb->pcb_gsbase = 0; 423 clear_pcb_flags(pcb, PCB_32BIT); 424 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 425 set_pcb_flags(pcb, PCB_FULL_IRET); 426 427 bzero((char *)regs, sizeof(struct trapframe)); 428 regs->tf_rip = imgp->entry_addr; 429 regs->tf_rsp = stack; 430 regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); 431 regs->tf_ss = _udatasel; 432 regs->tf_cs = _ucodesel; 433 regs->tf_ds = _udatasel; 434 regs->tf_es = _udatasel; 435 regs->tf_fs = _ufssel; 436 regs->tf_gs = _ugssel; 437 regs->tf_flags = TF_HASSEGS; 438 439 /* 440 * Reset the hardware debug registers if they were in use. 441 * They won't have any meaning for the newly exec'd process. 442 */ 443 if (pcb->pcb_flags & PCB_DBREGS) { 444 pcb->pcb_dr0 = 0; 445 pcb->pcb_dr1 = 0; 446 pcb->pcb_dr2 = 0; 447 pcb->pcb_dr3 = 0; 448 pcb->pcb_dr6 = 0; 449 pcb->pcb_dr7 = 0; 450 if (pcb == curpcb) { 451 /* 452 * Clear the debug registers on the running 453 * CPU, otherwise they will end up affecting 454 * the next process we switch to. 455 */ 456 reset_dbregs(); 457 } 458 clear_pcb_flags(pcb, PCB_DBREGS); 459 } 460 461 /* 462 * Drop the FP state if we hold it, so that the process gets a 463 * clean FP state if it uses the FPU again. 464 */ 465 fpstate_drop(td); 466 } 467 468 /* 469 * Copied from amd64/amd64/machdep.c 470 * 471 * XXX fpu state need? don't think so 472 */ 473 int 474 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 475 { 476 struct proc *p; 477 struct l_ucontext uc; 478 struct l_sigcontext *context; 479 struct trapframe *regs; 480 unsigned long rflags; 481 int error; 482 ksiginfo_t ksi; 483 484 regs = td->td_frame; 485 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 486 if (error != 0) 487 return (error); 488 489 p = td->td_proc; 490 context = &uc.uc_mcontext; 491 rflags = context->sc_rflags; 492 493 /* 494 * Don't allow users to change privileged or reserved flags. 495 */ 496 /* 497 * XXX do allow users to change the privileged flag PSL_RF. 498 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 499 * should sometimes set it there too. tf_rflags is kept in 500 * the signal context during signal handling and there is no 501 * other place to remember it, so the PSL_RF bit may be 502 * corrupted by the signal handler without us knowing. 503 * Corruption of the PSL_RF bit at worst causes one more or 504 * one less debugger trap, so allowing it is fairly harmless. 505 */ 506 507 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 508 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 509 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 510 return (EINVAL); 511 } 512 513 /* 514 * Don't allow users to load a valid privileged %cs. Let the 515 * hardware check for invalid selectors, excess privilege in 516 * other selectors, invalid %eip's and invalid %esp's. 517 */ 518 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 519 if (!CS_SECURE(context->sc_cs)) { 520 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 521 ksiginfo_init_trap(&ksi); 522 ksi.ksi_signo = SIGBUS; 523 ksi.ksi_code = BUS_OBJERR; 524 ksi.ksi_trapno = T_PROTFLT; 525 ksi.ksi_addr = (void *)regs->tf_rip; 526 trapsignal(td, &ksi); 527 return (EINVAL); 528 } 529 530 PROC_LOCK(p); 531 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 532 SIG_CANTMASK(td->td_sigmask); 533 signotify(td); 534 PROC_UNLOCK(p); 535 536 regs->tf_rdi = context->sc_rdi; 537 regs->tf_rsi = context->sc_rsi; 538 regs->tf_rdx = context->sc_rdx; 539 regs->tf_rbp = context->sc_rbp; 540 regs->tf_rbx = context->sc_rbx; 541 regs->tf_rcx = context->sc_rcx; 542 regs->tf_rax = context->sc_rax; 543 regs->tf_rip = context->sc_rip; 544 regs->tf_rsp = context->sc_rsp; 545 regs->tf_r8 = context->sc_r8; 546 regs->tf_r9 = context->sc_r9; 547 regs->tf_r10 = context->sc_r10; 548 regs->tf_r11 = context->sc_r11; 549 regs->tf_r12 = context->sc_r12; 550 regs->tf_r13 = context->sc_r13; 551 regs->tf_r14 = context->sc_r14; 552 regs->tf_r15 = context->sc_r15; 553 regs->tf_cs = context->sc_cs; 554 regs->tf_err = context->sc_err; 555 regs->tf_rflags = rflags; 556 557 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 558 return (EJUSTRETURN); 559 } 560 561 /* 562 * copied from amd64/amd64/machdep.c 563 * 564 * Send an interrupt to process. 565 */ 566 static void 567 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 568 { 569 struct l_rt_sigframe sf, *sfp; 570 struct proc *p; 571 struct thread *td; 572 struct sigacts *psp; 573 caddr_t sp; 574 struct trapframe *regs; 575 int sig, code; 576 int oonstack; 577 578 td = curthread; 579 p = td->td_proc; 580 PROC_LOCK_ASSERT(p, MA_OWNED); 581 sig = ksi->ksi_signo; 582 psp = p->p_sigacts; 583 code = ksi->ksi_code; 584 mtx_assert(&psp->ps_mtx, MA_OWNED); 585 regs = td->td_frame; 586 oonstack = sigonstack(regs->tf_rsp); 587 588 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 589 catcher, sig, mask, code); 590 591 /* Allocate space for the signal handler context. */ 592 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 593 SIGISMEMBER(psp->ps_sigonstack, sig)) { 594 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 595 sizeof(struct l_rt_sigframe); 596 } else 597 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 598 /* Align to 16 bytes. */ 599 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 600 mtx_unlock(&psp->ps_mtx); 601 602 /* Translate the signal. */ 603 sig = bsd_to_linux_signal(sig); 604 605 /* Save user context. */ 606 bzero(&sf, sizeof(sf)); 607 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 608 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 609 610 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 611 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 612 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 613 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 614 PROC_UNLOCK(p); 615 616 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 617 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 618 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 619 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 620 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 621 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 622 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 623 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 624 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 625 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 626 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 627 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 628 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 629 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 630 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 631 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 632 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 633 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 634 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 635 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 636 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 637 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 638 639 /* Build the argument list for the signal handler. */ 640 regs->tf_rdi = sig; /* arg 1 in %rdi */ 641 regs->tf_rax = 0; 642 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 643 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 644 645 sf.sf_handler = catcher; 646 /* Fill in POSIX parts. */ 647 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 648 649 /* Copy the sigframe out to the user's stack. */ 650 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 651 #ifdef DEBUG 652 printf("process %ld has trashed its stack\n", (long)p->p_pid); 653 #endif 654 PROC_LOCK(p); 655 sigexit(td, SIGILL); 656 } 657 658 regs->tf_rsp = (long)sfp; 659 regs->tf_rip = linux_rt_sigcode; 660 regs->tf_rflags &= ~(PSL_T | PSL_D); 661 regs->tf_cs = _ucodesel; 662 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 663 PROC_LOCK(p); 664 mtx_lock(&psp->ps_mtx); 665 } 666 667 /* 668 * If a Linux binary is exec'ing something, try this image activator 669 * first. We override standard shell script execution in order to 670 * be able to modify the interpreter path. We only do this if a Linux 671 * binary is doing the exec, so we do not create an EXEC module for it. 672 */ 673 static int 674 linux_exec_imgact_try(struct image_params *imgp) 675 { 676 const char *head = (const char *)imgp->image_header; 677 char *rpath; 678 int error = -1; 679 680 /* 681 * The interpreter for shell scripts run from a Linux binary needs 682 * to be located in /compat/linux if possible in order to recursively 683 * maintain Linux path emulation. 684 */ 685 if (((const short *)head)[0] == SHELLMAGIC) { 686 /* 687 * Run our normal shell image activator. If it succeeds then 688 * attempt to use the alternate path for the interpreter. If 689 * an alternate path is found, use our stringspace to store it. 690 */ 691 if ((error = exec_shell_imgact(imgp)) == 0) { 692 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc), 693 imgp->interpreter_name, UIO_SYSSPACE, &rpath, 0, 694 AT_FDCWD); 695 if (rpath != NULL) 696 imgp->args->fname_buf = 697 imgp->interpreter_name = rpath; 698 } 699 } 700 return (error); 701 } 702 703 #define LINUX_VSYSCALL_START (-10UL << 20) 704 #define LINUX_VSYSCALL_SZ 1024 705 706 const unsigned long linux_vsyscall_vector[] = { 707 LINUX_SYS_gettimeofday, 708 LINUX_SYS_linux_time, 709 /* getcpu not implemented */ 710 }; 711 712 static int 713 linux_vsyscall(struct thread *td) 714 { 715 struct trapframe *frame; 716 uint64_t retqaddr; 717 int code, traced; 718 int error; 719 720 frame = td->td_frame; 721 722 /* Check %rip for vsyscall area. */ 723 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 724 return (EINVAL); 725 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 726 return (EINVAL); 727 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 728 if (code >= nitems(linux_vsyscall_vector)) 729 return (EINVAL); 730 731 /* 732 * vsyscall called as callq *(%rax), so we must 733 * use return address from %rsp and also fixup %rsp. 734 */ 735 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 736 if (error) 737 return (error); 738 739 frame->tf_rip = retqaddr; 740 frame->tf_rax = linux_vsyscall_vector[code]; 741 frame->tf_rsp += 8; 742 743 traced = (frame->tf_flags & PSL_T); 744 745 amd64_syscall(td, traced); 746 747 return (0); 748 } 749 750 struct sysentvec elf_linux_sysvec = { 751 .sv_size = LINUX_SYS_MAXSYSCALL, 752 .sv_table = linux_sysent, 753 .sv_mask = 0, 754 .sv_errsize = ELAST + 1, 755 .sv_errtbl = bsd_to_linux_errno_generic, 756 .sv_transtrap = linux_translate_traps, 757 .sv_fixup = linux_fixup_elf, 758 .sv_sendsig = linux_rt_sendsig, 759 .sv_sigcode = &_binary_linux_locore_o_start, 760 .sv_szsigcode = &linux_szsigcode, 761 .sv_name = "Linux ELF64", 762 .sv_coredump = elf64_coredump, 763 .sv_imgact_try = linux_exec_imgact_try, 764 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 765 .sv_pagesize = PAGE_SIZE, 766 .sv_minuser = VM_MIN_ADDRESS, 767 .sv_maxuser = VM_MAXUSER_ADDRESS, 768 .sv_usrstack = USRSTACK, 769 .sv_psstrings = PS_STRINGS, 770 .sv_stackprot = VM_PROT_ALL, 771 .sv_copyout_strings = linux_copyout_strings, 772 .sv_setregs = linux_exec_setregs, 773 .sv_fixlimit = NULL, 774 .sv_maxssiz = NULL, 775 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 776 .sv_set_syscall_retval = linux_set_syscall_retval, 777 .sv_fetch_syscall_args = linux_fetch_syscall_args, 778 .sv_syscallnames = NULL, 779 .sv_shared_page_base = SHAREDPAGE, 780 .sv_shared_page_len = PAGE_SIZE, 781 .sv_schedtail = linux_schedtail, 782 .sv_thread_detach = linux_thread_detach, 783 .sv_trap = linux_vsyscall, 784 }; 785 786 static void 787 linux_vdso_install(void *param) 788 { 789 790 amd64_lower_shared_page(&elf_linux_sysvec); 791 792 linux_szsigcode = (&_binary_linux_locore_o_end - 793 &_binary_linux_locore_o_start); 794 795 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 796 panic("Linux invalid vdso size\n"); 797 798 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 799 800 linux_shared_page_obj = __elfN(linux_shared_page_init) 801 (&linux_shared_page_mapping); 802 803 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 804 805 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 806 linux_szsigcode); 807 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 808 809 linux_kplatform = linux_shared_page_mapping + 810 (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base); 811 } 812 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 813 (sysinit_cfunc_t)linux_vdso_install, NULL); 814 815 static void 816 linux_vdso_deinstall(void *param) 817 { 818 819 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 820 } 821 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 822 (sysinit_cfunc_t)linux_vdso_deinstall, NULL); 823 824 static char GNULINUX_ABI_VENDOR[] = "GNU"; 825 static int GNULINUX_ABI_DESC = 0; 826 827 static bool 828 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 829 { 830 const Elf32_Word *desc; 831 uintptr_t p; 832 833 p = (uintptr_t)(note + 1); 834 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 835 836 desc = (const Elf32_Word *)p; 837 if (desc[0] != GNULINUX_ABI_DESC) 838 return (false); 839 840 /* 841 * For Linux we encode osrel as follows (see linux_mib.c): 842 * VVVMMMIII (version, major, minor), see linux_mib.c. 843 */ 844 *osrel = desc[1] * 1000000 + desc[2] * 1000 + desc[3]; 845 846 return (true); 847 } 848 849 static Elf_Brandnote linux64_brandnote = { 850 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 851 .hdr.n_descsz = 16, 852 .hdr.n_type = 1, 853 .vendor = GNULINUX_ABI_VENDOR, 854 .flags = BN_TRANSLATE_OSREL, 855 .trans_osrel = linux_trans_osrel 856 }; 857 858 static Elf64_Brandinfo linux_glibc2brand = { 859 .brand = ELFOSABI_LINUX, 860 .machine = EM_X86_64, 861 .compat_3_brand = "Linux", 862 .emul_path = "/compat/linux", 863 .interp_path = "/lib64/ld-linux-x86-64.so.2", 864 .sysvec = &elf_linux_sysvec, 865 .interp_newpath = NULL, 866 .brand_note = &linux64_brandnote, 867 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 868 }; 869 870 static Elf64_Brandinfo linux_glibc2brandshort = { 871 .brand = ELFOSABI_LINUX, 872 .machine = EM_X86_64, 873 .compat_3_brand = "Linux", 874 .emul_path = "/compat/linux", 875 .interp_path = "/lib64/ld-linux.so.2", 876 .sysvec = &elf_linux_sysvec, 877 .interp_newpath = NULL, 878 .brand_note = &linux64_brandnote, 879 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 880 }; 881 882 static Elf64_Brandinfo linux_muslbrand = { 883 .brand = ELFOSABI_LINUX, 884 .machine = EM_X86_64, 885 .compat_3_brand = "Linux", 886 .emul_path = "/compat/linux", 887 .interp_path = "/lib/ld-musl-x86_64.so.1", 888 .sysvec = &elf_linux_sysvec, 889 .interp_newpath = NULL, 890 .brand_note = &linux64_brandnote, 891 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 892 }; 893 894 Elf64_Brandinfo *linux_brandlist[] = { 895 &linux_glibc2brand, 896 &linux_glibc2brandshort, 897 &linux_muslbrand, 898 NULL 899 }; 900 901 static int 902 linux64_elf_modevent(module_t mod, int type, void *data) 903 { 904 Elf64_Brandinfo **brandinfo; 905 int error; 906 struct linux_ioctl_handler **lihp; 907 908 error = 0; 909 910 switch(type) { 911 case MOD_LOAD: 912 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 913 ++brandinfo) 914 if (elf64_insert_brand_entry(*brandinfo) < 0) 915 error = EINVAL; 916 if (error == 0) { 917 SET_FOREACH(lihp, linux_ioctl_handler_set) 918 linux_ioctl_register_handler(*lihp); 919 LIST_INIT(&futex_list); 920 mtx_init(&futex_mtx, "ftllk64", NULL, MTX_DEF); 921 stclohz = (stathz ? stathz : hz); 922 if (bootverbose) 923 printf("Linux x86-64 ELF exec handler installed\n"); 924 } else 925 printf("cannot insert Linux x86-64 ELF brand handler\n"); 926 break; 927 case MOD_UNLOAD: 928 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 929 ++brandinfo) 930 if (elf64_brand_inuse(*brandinfo)) 931 error = EBUSY; 932 if (error == 0) { 933 for (brandinfo = &linux_brandlist[0]; 934 *brandinfo != NULL; ++brandinfo) 935 if (elf64_remove_brand_entry(*brandinfo) < 0) 936 error = EINVAL; 937 } 938 if (error == 0) { 939 SET_FOREACH(lihp, linux_ioctl_handler_set) 940 linux_ioctl_unregister_handler(*lihp); 941 mtx_destroy(&futex_mtx); 942 if (bootverbose) 943 printf("Linux ELF exec handler removed\n"); 944 } else 945 printf("Could not deinstall ELF interpreter entry\n"); 946 break; 947 default: 948 return (EOPNOTSUPP); 949 } 950 return (error); 951 } 952 953 static moduledata_t linux64_elf_mod = { 954 "linux64elf", 955 linux64_elf_modevent, 956 0 957 }; 958 959 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 960 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 961 FEATURE(linux64, "Linux 64bit support"); 962