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 elf_linux_fixup(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 void linux_exec_setregs(struct thread *td, struct image_params *imgp, 130 u_long stack); 131 static int linux_vsyscall(struct thread *td); 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, -61, -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)<nitems(_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) 220 { 221 struct proc *p; 222 struct trapframe *frame; 223 struct syscall_args *sa; 224 225 p = td->td_proc; 226 frame = td->td_frame; 227 sa = &td->td_sa; 228 229 sa->args[0] = frame->tf_rdi; 230 sa->args[1] = frame->tf_rsi; 231 sa->args[2] = frame->tf_rdx; 232 sa->args[3] = frame->tf_rcx; 233 sa->args[4] = frame->tf_r8; 234 sa->args[5] = frame->tf_r9; 235 sa->code = frame->tf_rax; 236 237 if (sa->code >= p->p_sysent->sv_size) 238 /* nosys */ 239 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 240 else 241 sa->callp = &p->p_sysent->sv_table[sa->code]; 242 sa->narg = sa->callp->sy_narg; 243 244 td->td_retval[0] = 0; 245 return (0); 246 } 247 248 static void 249 linux_set_syscall_retval(struct thread *td, int error) 250 { 251 struct trapframe *frame = td->td_frame; 252 253 /* 254 * On Linux only %rcx and %r11 values are not preserved across 255 * the syscall. 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 /* Calculate string base and vector table pointers. */ 337 if (imgp->execpath != NULL && imgp->auxargs != NULL) 338 execpath_len = strlen(imgp->execpath) + 1; 339 else 340 execpath_len = 0; 341 342 p = imgp->proc; 343 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 344 destp = (caddr_t)arginfo - SPARE_USRSPACE - 345 roundup(sizeof(canary), sizeof(char *)) - 346 roundup(execpath_len, sizeof(char *)) - 347 roundup(ARG_MAX - imgp->args->stringspace, sizeof(char *)); 348 349 if (execpath_len != 0) { 350 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 351 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 352 } 353 354 /* Prepare the canary for SSP. */ 355 arc4rand(canary, sizeof(canary), 0); 356 imgp->canary = (uintptr_t)arginfo - 357 roundup(execpath_len, sizeof(char *)) - 358 roundup(sizeof(canary), sizeof(char *)); 359 copyout(canary, (void *)imgp->canary, sizeof(canary)); 360 361 /* If we have a valid auxargs ptr, prepare some room on the stack. */ 362 if (imgp->auxargs) { 363 /* 364 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for 365 * lower compatibility. 366 */ 367 imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : 368 (LINUX_AT_COUNT * 2); 369 370 /* 371 * The '+ 2' is for the null pointers at the end of each of 372 * the arg and env vector sets,and imgp->auxarg_size is room 373 * for argument of Runtime loader. 374 */ 375 vectp = (char **)(destp - (imgp->args->argc + 376 imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); 377 378 } else { 379 /* 380 * The '+ 2' is for the null pointers at the end of each of 381 * the arg and env vector sets 382 */ 383 vectp = (char **)(destp - (imgp->args->argc + 384 imgp->args->envc + 2) * sizeof(char *)); 385 } 386 387 /* vectp also becomes our initial stack base. */ 388 stack_base = (register_t *)vectp; 389 390 stringp = imgp->args->begin_argv; 391 argc = imgp->args->argc; 392 envc = imgp->args->envc; 393 394 /* Copy out strings - arguments and environment. */ 395 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 396 397 /* Fill in "ps_strings" struct for ps, w, etc. */ 398 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 399 suword(&arginfo->ps_nargvstr, argc); 400 401 /* Fill in argument portion of vector table. */ 402 for (; argc > 0; --argc) { 403 suword(vectp++, (long)(intptr_t)destp); 404 while (*stringp++ != 0) 405 destp++; 406 destp++; 407 } 408 409 /* A null vector table pointer separates the argp's from the envp's. */ 410 suword(vectp++, 0); 411 412 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 413 suword(&arginfo->ps_nenvstr, envc); 414 415 /* Fill in environment portion of vector table. */ 416 for (; envc > 0; --envc) { 417 suword(vectp++, (long)(intptr_t)destp); 418 while (*stringp++ != 0) 419 destp++; 420 destp++; 421 } 422 423 /* The end of the vector table is a null pointer. */ 424 suword(vectp, 0); 425 return (stack_base); 426 } 427 428 /* 429 * Reset registers to default values on exec. 430 */ 431 static void 432 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 433 { 434 struct trapframe *regs = td->td_frame; 435 struct pcb *pcb = td->td_pcb; 436 437 if (td->td_proc->p_md.md_ldt != NULL) 438 user_ldt_free(td); 439 440 pcb->pcb_fsbase = 0; 441 pcb->pcb_gsbase = 0; 442 clear_pcb_flags(pcb, PCB_32BIT); 443 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 444 set_pcb_flags(pcb, PCB_FULL_IRET); 445 446 bzero((char *)regs, sizeof(struct trapframe)); 447 regs->tf_rip = imgp->entry_addr; 448 regs->tf_rsp = stack; 449 regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); 450 regs->tf_ss = _udatasel; 451 regs->tf_cs = _ucodesel; 452 regs->tf_ds = _udatasel; 453 regs->tf_es = _udatasel; 454 regs->tf_fs = _ufssel; 455 regs->tf_gs = _ugssel; 456 regs->tf_flags = TF_HASSEGS; 457 458 /* 459 * Reset the hardware debug registers if they were in use. 460 * They won't have any meaning for the newly exec'd process. 461 */ 462 if (pcb->pcb_flags & PCB_DBREGS) { 463 pcb->pcb_dr0 = 0; 464 pcb->pcb_dr1 = 0; 465 pcb->pcb_dr2 = 0; 466 pcb->pcb_dr3 = 0; 467 pcb->pcb_dr6 = 0; 468 pcb->pcb_dr7 = 0; 469 if (pcb == curpcb) { 470 /* 471 * Clear the debug registers on the running 472 * CPU, otherwise they will end up affecting 473 * the next process we switch to. 474 */ 475 reset_dbregs(); 476 } 477 clear_pcb_flags(pcb, PCB_DBREGS); 478 } 479 480 /* 481 * Drop the FP state if we hold it, so that the process gets a 482 * clean FP state if it uses the FPU again. 483 */ 484 fpstate_drop(td); 485 } 486 487 /* 488 * Copied from amd64/amd64/machdep.c 489 * 490 * XXX fpu state need? don't think so 491 */ 492 int 493 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 494 { 495 struct proc *p; 496 struct l_ucontext uc; 497 struct l_sigcontext *context; 498 struct trapframe *regs; 499 unsigned long rflags; 500 int error; 501 ksiginfo_t ksi; 502 503 regs = td->td_frame; 504 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 505 if (error != 0) 506 return (error); 507 508 p = td->td_proc; 509 context = &uc.uc_mcontext; 510 rflags = context->sc_rflags; 511 512 /* 513 * Don't allow users to change privileged or reserved flags. 514 */ 515 /* 516 * XXX do allow users to change the privileged flag PSL_RF. 517 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 518 * should sometimes set it there too. tf_rflags is kept in 519 * the signal context during signal handling and there is no 520 * other place to remember it, so the PSL_RF bit may be 521 * corrupted by the signal handler without us knowing. 522 * Corruption of the PSL_RF bit at worst causes one more or 523 * one less debugger trap, so allowing it is fairly harmless. 524 */ 525 526 #define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 527 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 528 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 529 return (EINVAL); 530 } 531 532 /* 533 * Don't allow users to load a valid privileged %cs. Let the 534 * hardware check for invalid selectors, excess privilege in 535 * other selectors, invalid %eip's and invalid %esp's. 536 */ 537 #define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 538 if (!CS_SECURE(context->sc_cs)) { 539 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 540 ksiginfo_init_trap(&ksi); 541 ksi.ksi_signo = SIGBUS; 542 ksi.ksi_code = BUS_OBJERR; 543 ksi.ksi_trapno = T_PROTFLT; 544 ksi.ksi_addr = (void *)regs->tf_rip; 545 trapsignal(td, &ksi); 546 return (EINVAL); 547 } 548 549 PROC_LOCK(p); 550 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 551 SIG_CANTMASK(td->td_sigmask); 552 signotify(td); 553 PROC_UNLOCK(p); 554 555 regs->tf_rdi = context->sc_rdi; 556 regs->tf_rsi = context->sc_rsi; 557 regs->tf_rdx = context->sc_rdx; 558 regs->tf_rbp = context->sc_rbp; 559 regs->tf_rbx = context->sc_rbx; 560 regs->tf_rcx = context->sc_rcx; 561 regs->tf_rax = context->sc_rax; 562 regs->tf_rip = context->sc_rip; 563 regs->tf_rsp = context->sc_rsp; 564 regs->tf_r8 = context->sc_r8; 565 regs->tf_r9 = context->sc_r9; 566 regs->tf_r10 = context->sc_r10; 567 regs->tf_r11 = context->sc_r11; 568 regs->tf_r12 = context->sc_r12; 569 regs->tf_r13 = context->sc_r13; 570 regs->tf_r14 = context->sc_r14; 571 regs->tf_r15 = context->sc_r15; 572 regs->tf_cs = context->sc_cs; 573 regs->tf_err = context->sc_err; 574 regs->tf_rflags = rflags; 575 576 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 577 return (EJUSTRETURN); 578 } 579 580 /* 581 * copied from amd64/amd64/machdep.c 582 * 583 * Send an interrupt to process. 584 */ 585 static void 586 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 587 { 588 struct l_rt_sigframe sf, *sfp; 589 struct proc *p; 590 struct thread *td; 591 struct sigacts *psp; 592 caddr_t sp; 593 struct trapframe *regs; 594 int sig, code; 595 int oonstack; 596 597 td = curthread; 598 p = td->td_proc; 599 PROC_LOCK_ASSERT(p, MA_OWNED); 600 sig = ksi->ksi_signo; 601 psp = p->p_sigacts; 602 code = ksi->ksi_code; 603 mtx_assert(&psp->ps_mtx, MA_OWNED); 604 regs = td->td_frame; 605 oonstack = sigonstack(regs->tf_rsp); 606 607 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 608 catcher, sig, mask, code); 609 610 /* Allocate space for the signal handler context. */ 611 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 612 SIGISMEMBER(psp->ps_sigonstack, sig)) { 613 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 614 sizeof(struct l_rt_sigframe); 615 } else 616 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 617 /* Align to 16 bytes. */ 618 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 619 mtx_unlock(&psp->ps_mtx); 620 621 /* Translate the signal. */ 622 sig = bsd_to_linux_signal(sig); 623 624 /* Save user context. */ 625 bzero(&sf, sizeof(sf)); 626 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 627 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 628 629 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 630 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 631 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 632 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 633 PROC_UNLOCK(p); 634 635 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 636 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 637 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 638 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 639 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 640 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 641 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 642 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 643 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 644 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 645 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 646 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 647 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 648 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 649 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 650 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 651 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 652 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 653 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 654 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 655 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 656 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 657 658 /* Build the argument list for the signal handler. */ 659 regs->tf_rdi = sig; /* arg 1 in %rdi */ 660 regs->tf_rax = 0; 661 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 662 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 663 664 sf.sf_handler = catcher; 665 /* Fill in POSIX parts. */ 666 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 667 668 /* Copy the sigframe out to the user's stack. */ 669 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 670 #ifdef DEBUG 671 printf("process %ld has trashed its stack\n", (long)p->p_pid); 672 #endif 673 PROC_LOCK(p); 674 sigexit(td, SIGILL); 675 } 676 677 regs->tf_rsp = (long)sfp; 678 regs->tf_rip = linux_rt_sigcode; 679 regs->tf_rflags &= ~(PSL_T | PSL_D); 680 regs->tf_cs = _ucodesel; 681 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 682 PROC_LOCK(p); 683 mtx_lock(&psp->ps_mtx); 684 } 685 686 /* 687 * If a Linux binary is exec'ing something, try this image activator 688 * first. We override standard shell script execution in order to 689 * be able to modify the interpreter path. We only do this if a Linux 690 * binary is doing the exec, so we do not create an EXEC module for it. 691 */ 692 static int exec_linux_imgact_try(struct image_params *iparams); 693 694 static int 695 exec_linux_imgact_try(struct image_params *imgp) 696 { 697 const char *head = (const char *)imgp->image_header; 698 char *rpath; 699 int error = -1; 700 701 /* 702 * The interpreter for shell scripts run from a Linux binary needs 703 * to be located in /compat/linux if possible in order to recursively 704 * maintain Linux path emulation. 705 */ 706 if (((const short *)head)[0] == SHELLMAGIC) { 707 /* 708 * Run our normal shell image activator. If it succeeds 709 * attempt to use the alternate path for the interpreter. 710 * If an alternate path is found, use our stringspace 711 * to store it. 712 */ 713 if ((error = exec_shell_imgact(imgp)) == 0) { 714 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc), 715 imgp->interpreter_name, UIO_SYSSPACE, 716 &rpath, 0, AT_FDCWD); 717 if (rpath != NULL) 718 imgp->args->fname_buf = 719 imgp->interpreter_name = rpath; 720 } 721 } 722 return (error); 723 } 724 725 #define LINUX_VSYSCALL_START (-10UL << 20) 726 #define LINUX_VSYSCALL_SZ 1024 727 728 const unsigned long linux_vsyscall_vector[] = { 729 LINUX_SYS_gettimeofday, 730 LINUX_SYS_linux_time, 731 /* getcpu not implemented */ 732 }; 733 734 static int 735 linux_vsyscall(struct thread *td) 736 { 737 struct trapframe *frame; 738 uint64_t retqaddr; 739 int code, traced; 740 int error; 741 742 frame = td->td_frame; 743 744 /* Check %rip for vsyscall area. */ 745 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 746 return (EINVAL); 747 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 748 return (EINVAL); 749 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 750 if (code >= nitems(linux_vsyscall_vector)) 751 return (EINVAL); 752 753 /* 754 * vsyscall called as callq *(%rax), so we must 755 * use return address from %rsp and also fixup %rsp. 756 */ 757 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 758 if (error) 759 return (error); 760 761 frame->tf_rip = retqaddr; 762 frame->tf_rax = linux_vsyscall_vector[code]; 763 frame->tf_rsp += 8; 764 765 traced = (frame->tf_flags & PSL_T); 766 767 amd64_syscall(td, traced); 768 769 return (0); 770 } 771 772 struct sysentvec elf_linux_sysvec = { 773 .sv_size = LINUX_SYS_MAXSYSCALL, 774 .sv_table = linux_sysent, 775 .sv_mask = 0, 776 .sv_errsize = ELAST + 1, 777 .sv_errtbl = bsd_to_linux_errno, 778 .sv_transtrap = translate_traps, 779 .sv_fixup = elf_linux_fixup, 780 .sv_sendsig = linux_rt_sendsig, 781 .sv_sigcode = &_binary_linux_locore_o_start, 782 .sv_szsigcode = &linux_szsigcode, 783 .sv_name = "Linux ELF64", 784 .sv_coredump = elf64_coredump, 785 .sv_imgact_try = exec_linux_imgact_try, 786 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 787 .sv_pagesize = PAGE_SIZE, 788 .sv_minuser = VM_MIN_ADDRESS, 789 .sv_maxuser = VM_MAXUSER_ADDRESS, 790 .sv_usrstack = USRSTACK, 791 .sv_psstrings = PS_STRINGS, 792 .sv_stackprot = VM_PROT_ALL, 793 .sv_copyout_strings = linux_copyout_strings, 794 .sv_setregs = linux_exec_setregs, 795 .sv_fixlimit = NULL, 796 .sv_maxssiz = NULL, 797 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 798 .sv_set_syscall_retval = linux_set_syscall_retval, 799 .sv_fetch_syscall_args = linux_fetch_syscall_args, 800 .sv_syscallnames = NULL, 801 .sv_shared_page_base = SHAREDPAGE, 802 .sv_shared_page_len = PAGE_SIZE, 803 .sv_schedtail = linux_schedtail, 804 .sv_thread_detach = linux_thread_detach, 805 .sv_trap = linux_vsyscall, 806 }; 807 808 static void 809 linux_vdso_install(void *param) 810 { 811 812 amd64_lower_shared_page(&elf_linux_sysvec); 813 814 linux_szsigcode = (&_binary_linux_locore_o_end - 815 &_binary_linux_locore_o_start); 816 817 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 818 panic("Linux invalid vdso size\n"); 819 820 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 821 822 linux_shared_page_obj = __elfN(linux_shared_page_init) 823 (&linux_shared_page_mapping); 824 825 __elfN(linux_vdso_reloc)(&elf_linux_sysvec); 826 827 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 828 linux_szsigcode); 829 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 830 831 linux_kplatform = linux_shared_page_mapping + 832 (linux_platform - (caddr_t)elf_linux_sysvec.sv_shared_page_base); 833 } 834 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 835 (sysinit_cfunc_t)linux_vdso_install, NULL); 836 837 static void 838 linux_vdso_deinstall(void *param) 839 { 840 841 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 842 }; 843 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 844 (sysinit_cfunc_t)linux_vdso_deinstall, NULL); 845 846 static char GNULINUX_ABI_VENDOR[] = "GNU"; 847 static int GNULINUX_ABI_DESC = 0; 848 849 static bool 850 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 851 { 852 const Elf32_Word *desc; 853 uintptr_t p; 854 855 p = (uintptr_t)(note + 1); 856 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 857 858 desc = (const Elf32_Word *)p; 859 if (desc[0] != GNULINUX_ABI_DESC) 860 return (false); 861 862 /* 863 * For Linux we encode osrel as follows (see linux_mib.c): 864 * VVVMMMIII (version, major, minor), see linux_mib.c. 865 */ 866 *osrel = desc[1] * 1000000 + desc[2] * 1000 + desc[3]; 867 868 return (true); 869 } 870 871 static Elf_Brandnote linux64_brandnote = { 872 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 873 .hdr.n_descsz = 16, 874 .hdr.n_type = 1, 875 .vendor = GNULINUX_ABI_VENDOR, 876 .flags = BN_TRANSLATE_OSREL, 877 .trans_osrel = linux_trans_osrel 878 }; 879 880 static Elf64_Brandinfo linux_glibc2brand = { 881 .brand = ELFOSABI_LINUX, 882 .machine = EM_X86_64, 883 .compat_3_brand = "Linux", 884 .emul_path = "/compat/linux", 885 .interp_path = "/lib64/ld-linux-x86-64.so.2", 886 .sysvec = &elf_linux_sysvec, 887 .interp_newpath = NULL, 888 .brand_note = &linux64_brandnote, 889 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 890 }; 891 892 static Elf64_Brandinfo linux_glibc2brandshort = { 893 .brand = ELFOSABI_LINUX, 894 .machine = EM_X86_64, 895 .compat_3_brand = "Linux", 896 .emul_path = "/compat/linux", 897 .interp_path = "/lib64/ld-linux.so.2", 898 .sysvec = &elf_linux_sysvec, 899 .interp_newpath = NULL, 900 .brand_note = &linux64_brandnote, 901 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 902 }; 903 904 static Elf64_Brandinfo linux_muslbrand = { 905 .brand = ELFOSABI_LINUX, 906 .machine = EM_X86_64, 907 .compat_3_brand = "Linux", 908 .emul_path = "/compat/linux", 909 .interp_path = "/lib/ld-musl-x86_64.so.1", 910 .sysvec = &elf_linux_sysvec, 911 .interp_newpath = NULL, 912 .brand_note = &linux64_brandnote, 913 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 914 }; 915 916 Elf64_Brandinfo *linux_brandlist[] = { 917 &linux_glibc2brand, 918 &linux_glibc2brandshort, 919 &linux_muslbrand, 920 NULL 921 }; 922 923 static int 924 linux64_elf_modevent(module_t mod, int type, void *data) 925 { 926 Elf64_Brandinfo **brandinfo; 927 int error; 928 struct linux_ioctl_handler **lihp; 929 930 error = 0; 931 932 switch(type) { 933 case MOD_LOAD: 934 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 935 ++brandinfo) 936 if (elf64_insert_brand_entry(*brandinfo) < 0) 937 error = EINVAL; 938 if (error == 0) { 939 SET_FOREACH(lihp, linux_ioctl_handler_set) 940 linux_ioctl_register_handler(*lihp); 941 LIST_INIT(&futex_list); 942 mtx_init(&futex_mtx, "ftllk64", NULL, MTX_DEF); 943 stclohz = (stathz ? stathz : hz); 944 if (bootverbose) 945 printf("Linux x86-64 ELF exec handler installed\n"); 946 } else 947 printf("cannot insert Linux x86-64 ELF brand handler\n"); 948 break; 949 case MOD_UNLOAD: 950 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 951 ++brandinfo) 952 if (elf64_brand_inuse(*brandinfo)) 953 error = EBUSY; 954 if (error == 0) { 955 for (brandinfo = &linux_brandlist[0]; 956 *brandinfo != NULL; ++brandinfo) 957 if (elf64_remove_brand_entry(*brandinfo) < 0) 958 error = EINVAL; 959 } 960 if (error == 0) { 961 SET_FOREACH(lihp, linux_ioctl_handler_set) 962 linux_ioctl_unregister_handler(*lihp); 963 mtx_destroy(&futex_mtx); 964 if (bootverbose) 965 printf("Linux ELF exec handler removed\n"); 966 } else 967 printf("Could not deinstall ELF interpreter entry\n"); 968 break; 969 default: 970 return (EOPNOTSUPP); 971 } 972 return (error); 973 } 974 975 static moduledata_t linux64_elf_mod = { 976 "linux64elf", 977 linux64_elf_modevent, 978 0 979 }; 980 981 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 982 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 983 FEATURE(linux64, "Linux 64bit support"); 984