1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1994-1996 Søren Schmidt 5 * Copyright (c) 2018 Turing Robotic Industries Inc. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/cdefs.h> 35 #include <sys/elf.h> 36 #include <sys/exec.h> 37 #include <sys/imgact.h> 38 #include <sys/imgact_elf.h> 39 #include <sys/kernel.h> 40 #include <sys/ktr.h> 41 #include <sys/lock.h> 42 #include <sys/module.h> 43 #include <sys/mutex.h> 44 #include <sys/proc.h> 45 #include <sys/stddef.h> 46 #include <sys/signalvar.h> 47 #include <sys/syscallsubr.h> 48 #include <sys/sysctl.h> 49 #include <sys/sysent.h> 50 51 #include <vm/vm.h> 52 #include <vm/pmap.h> 53 #include <vm/vm_map.h> 54 #include <vm/vm_extern.h> 55 #include <vm/vm_object.h> 56 #include <vm/vm_page.h> 57 #include <vm/vm_param.h> 58 59 #include <arm64/linux/linux.h> 60 #include <arm64/linux/linux_proto.h> 61 #include <compat/linux/linux_dtrace.h> 62 #include <compat/linux/linux_emul.h> 63 #include <compat/linux/linux_fork.h> 64 #include <compat/linux/linux_ioctl.h> 65 #include <compat/linux/linux_mib.h> 66 #include <compat/linux/linux_misc.h> 67 #include <compat/linux/linux_signal.h> 68 #include <compat/linux/linux_util.h> 69 #include <compat/linux/linux_vdso.h> 70 71 #include <arm64/linux/linux_sigframe.h> 72 73 #include <machine/md_var.h> 74 75 #ifdef VFP 76 #include <machine/vfp.h> 77 #endif 78 79 MODULE_VERSION(linux64elf, 1); 80 81 #define LINUX_VDSOPAGE_SIZE PAGE_SIZE * 2 82 #define LINUX_VDSOPAGE (VM_MAXUSER_ADDRESS - \ 83 LINUX_VDSOPAGE_SIZE) 84 #define LINUX_SHAREDPAGE (LINUX_VDSOPAGE - PAGE_SIZE) 85 /* 86 * PAGE_SIZE - the size 87 * of the native SHAREDPAGE 88 */ 89 #define LINUX_USRSTACK LINUX_SHAREDPAGE 90 #define LINUX_PS_STRINGS (LINUX_USRSTACK - \ 91 sizeof(struct ps_strings)) 92 93 static int linux_szsigcode; 94 static vm_object_t linux_vdso_obj; 95 static char *linux_vdso_mapping; 96 extern char _binary_linux_vdso_so_o_start; 97 extern char _binary_linux_vdso_so_o_end; 98 static vm_offset_t linux_vdso_base; 99 100 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 101 extern const char *linux_syscallnames[]; 102 103 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 104 105 static int linux_copyout_strings(struct image_params *imgp, 106 uintptr_t *stack_base); 107 static int linux_elf_fixup(uintptr_t *stack_base, 108 struct image_params *iparams); 109 static bool linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 110 static void linux_vdso_install(const void *param); 111 static void linux_vdso_deinstall(const void *param); 112 static void linux_vdso_reloc(char *mapping, Elf_Addr offset); 113 static void linux_set_syscall_retval(struct thread *td, int error); 114 static int linux_fetch_syscall_args(struct thread *td); 115 static void linux_exec_setregs(struct thread *td, struct image_params *imgp, 116 uintptr_t stack); 117 static void linux_exec_sysvec_init(void *param); 118 static int linux_on_exec_vmspace(struct proc *p, 119 struct image_params *imgp); 120 121 /* DTrace init */ 122 LIN_SDT_PROVIDER_DECLARE(LINUX_DTRACE); 123 124 /* DTrace probes */ 125 LIN_SDT_PROBE_DEFINE0(sysvec, linux_exec_setregs, todo); 126 LIN_SDT_PROBE_DEFINE0(sysvec, linux_copyout_auxargs, todo); 127 LIN_SDT_PROBE_DEFINE0(sysvec, linux_elf_fixup, todo); 128 129 LINUX_VDSO_SYM_CHAR(linux_platform); 130 LINUX_VDSO_SYM_INTPTR(kern_timekeep_base); 131 LINUX_VDSO_SYM_INTPTR(linux_vdso_sigcode); 132 133 static int 134 linux_fetch_syscall_args(struct thread *td) 135 { 136 struct proc *p; 137 struct syscall_args *sa; 138 register_t *ap; 139 140 p = td->td_proc; 141 ap = td->td_frame->tf_x; 142 sa = &td->td_sa; 143 144 sa->code = td->td_frame->tf_x[8]; 145 sa->original_code = sa->code; 146 /* LINUXTODO: generic syscall? */ 147 if (sa->code >= p->p_sysent->sv_size) 148 sa->callp = &p->p_sysent->sv_table[0]; 149 else 150 sa->callp = &p->p_sysent->sv_table[sa->code]; 151 152 if (sa->callp->sy_narg > nitems(sa->args)) 153 panic("ARM64TODO: Could we have more than %zu args?", 154 nitems(sa->args)); 155 memcpy(sa->args, ap, nitems(sa->args) * sizeof(register_t)); 156 157 td->td_retval[0] = 0; 158 return (0); 159 } 160 161 static void 162 linux_set_syscall_retval(struct thread *td, int error) 163 { 164 165 td->td_retval[1] = td->td_frame->tf_x[1]; 166 cpu_set_syscall_retval(td, error); 167 168 if (__predict_false(error != 0)) { 169 if (error != ERESTART && error != EJUSTRETURN) 170 td->td_frame->tf_x[0] = bsd_to_linux_errno(error); 171 } 172 } 173 174 static int 175 linux_copyout_auxargs(struct image_params *imgp, uintptr_t base) 176 { 177 Elf_Auxargs *args; 178 Elf_Auxinfo *argarray, *pos; 179 struct proc *p; 180 int error, issetugid; 181 182 LIN_SDT_PROBE0(sysvec, linux_copyout_auxargs, todo); 183 p = imgp->proc; 184 185 args = (Elf64_Auxargs *)imgp->auxargs; 186 argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP, 187 M_WAITOK | M_ZERO); 188 189 issetugid = p->p_flag & P_SUGID ? 1 : 0; 190 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, linux_vdso_base); 191 AUXARGS_ENTRY(pos, LINUX_AT_MINSIGSTKSZ, LINUX_MINSIGSTKSZ); 192 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, *imgp->sysent->sv_hwcap); 193 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 194 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 195 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 196 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 197 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 198 AUXARGS_ENTRY(pos, AT_BASE, args->base); 199 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 200 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 201 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 202 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 203 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 204 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 205 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 206 AUXARGS_ENTRY_PTR(pos, LINUX_AT_RANDOM, imgp->canary); 207 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP2, *imgp->sysent->sv_hwcap2); 208 if (imgp->execpathp != 0) 209 AUXARGS_ENTRY_PTR(pos, LINUX_AT_EXECFN, imgp->execpathp); 210 if (args->execfd != -1) 211 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 212 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 213 AUXARGS_ENTRY(pos, AT_NULL, 0); 214 215 free(imgp->auxargs, M_TEMP); 216 imgp->auxargs = NULL; 217 KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs")); 218 219 error = copyout(argarray, (void *)base, 220 sizeof(*argarray) * LINUX_AT_COUNT); 221 free(argarray, M_TEMP); 222 return (error); 223 } 224 225 static int 226 linux_elf_fixup(uintptr_t *stack_base, struct image_params *imgp) 227 { 228 229 LIN_SDT_PROBE0(sysvec, linux_elf_fixup, todo); 230 231 return (0); 232 } 233 234 /* 235 * Copy strings out to the new process address space, constructing new arg 236 * and env vector tables. Return a pointer to the base so that it can be used 237 * as the initial stack pointer. 238 * LINUXTODO: deduplicate against other linuxulator archs 239 */ 240 static int 241 linux_copyout_strings(struct image_params *imgp, uintptr_t *stack_base) 242 { 243 char **vectp; 244 char *stringp; 245 uintptr_t destp, ustringp; 246 struct ps_strings *arginfo; 247 char canary[LINUX_AT_RANDOM_LEN]; 248 size_t execpath_len; 249 struct proc *p; 250 int argc, envc, error; 251 252 p = imgp->proc; 253 arginfo = (struct ps_strings *)PROC_PS_STRINGS(p); 254 destp = (uintptr_t)arginfo; 255 256 if (imgp->execpath != NULL && imgp->auxargs != NULL) { 257 execpath_len = strlen(imgp->execpath) + 1; 258 destp -= execpath_len; 259 destp = rounddown2(destp, sizeof(void *)); 260 imgp->execpathp = (void *)destp; 261 error = copyout(imgp->execpath, imgp->execpathp, execpath_len); 262 if (error != 0) 263 return (error); 264 } 265 266 /* Prepare the canary for SSP. */ 267 arc4rand(canary, sizeof(canary), 0); 268 destp -= roundup(sizeof(canary), sizeof(void *)); 269 imgp->canary = (void *)destp; 270 error = copyout(canary, imgp->canary, sizeof(canary)); 271 if (error != 0) 272 return (error); 273 274 /* Allocate room for the argument and environment strings. */ 275 destp -= ARG_MAX - imgp->args->stringspace; 276 destp = rounddown2(destp, sizeof(void *)); 277 ustringp = destp; 278 279 if (imgp->auxargs) { 280 /* 281 * Allocate room on the stack for the ELF auxargs 282 * array. It has up to LINUX_AT_COUNT entries. 283 */ 284 destp -= LINUX_AT_COUNT * sizeof(Elf64_Auxinfo); 285 destp = rounddown2(destp, sizeof(void *)); 286 } 287 288 vectp = (char **)destp; 289 290 /* 291 * Allocate room for argc and the argv[] and env vectors including the 292 * terminating NULL pointers. 293 */ 294 vectp -= 1 + imgp->args->argc + 1 + imgp->args->envc + 1; 295 vectp = (char **)STACKALIGN(vectp); 296 297 /* vectp also becomes our initial stack base. */ 298 *stack_base = (uintptr_t)vectp; 299 300 stringp = imgp->args->begin_argv; 301 argc = imgp->args->argc; 302 envc = imgp->args->envc; 303 304 /* Copy out strings - arguments and environment. */ 305 error = copyout(stringp, (void *)ustringp, 306 ARG_MAX - imgp->args->stringspace); 307 if (error != 0) 308 return (error); 309 310 /* Fill in "ps_strings" struct for ps, w, etc. */ 311 if (suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp) != 0 || 312 suword(&arginfo->ps_nargvstr, argc) != 0) 313 return (EFAULT); 314 315 if (suword(vectp++, argc) != 0) 316 return (EFAULT); 317 318 /* Fill in argument portion of vector table. */ 319 for (; argc > 0; --argc) { 320 if (suword(vectp++, ustringp) != 0) 321 return (EFAULT); 322 while (*stringp++ != 0) 323 ustringp++; 324 ustringp++; 325 } 326 327 /* A null vector table pointer separates the argp's from the envp's. */ 328 if (suword(vectp++, 0) != 0) 329 return (EFAULT); 330 331 if (suword(&arginfo->ps_envstr, (long)(intptr_t)vectp) != 0 || 332 suword(&arginfo->ps_nenvstr, envc) != 0) 333 return (EFAULT); 334 335 /* Fill in environment portion of vector table. */ 336 for (; envc > 0; --envc) { 337 if (suword(vectp++, ustringp) != 0) 338 return (EFAULT); 339 while (*stringp++ != 0) 340 ustringp++; 341 ustringp++; 342 } 343 344 /* The end of the vector table is a null pointer. */ 345 if (suword(vectp, 0) != 0) 346 return (EFAULT); 347 348 if (imgp->auxargs) { 349 vectp++; 350 error = imgp->sysent->sv_copyout_auxargs(imgp, 351 (uintptr_t)vectp); 352 if (error != 0) 353 return (error); 354 } 355 356 return (0); 357 } 358 359 /* 360 * Reset registers to default values on exec. 361 */ 362 static void 363 linux_exec_setregs(struct thread *td, struct image_params *imgp, 364 uintptr_t stack) 365 { 366 struct trapframe *regs = td->td_frame; 367 struct pcb *pcb = td->td_pcb; 368 369 /* LINUXTODO: validate */ 370 LIN_SDT_PROBE0(sysvec, linux_exec_setregs, todo); 371 372 memset(regs, 0, sizeof(*regs)); 373 /* glibc start.S registers function pointer in x0 with atexit. */ 374 regs->tf_sp = stack; 375 #if 0 /* LINUXTODO: See if this is used. */ 376 regs->tf_lr = imgp->entry_addr; 377 #else 378 regs->tf_lr = 0xffffffffffffffff; 379 #endif 380 regs->tf_elr = imgp->entry_addr; 381 382 pcb->pcb_tpidr_el0 = 0; 383 pcb->pcb_tpidrro_el0 = 0; 384 WRITE_SPECIALREG(tpidrro_el0, 0); 385 WRITE_SPECIALREG(tpidr_el0, 0); 386 387 #ifdef VFP 388 vfp_reset_state(td, pcb); 389 #endif 390 391 /* 392 * Clear debug register state. It is not applicable to the new process. 393 */ 394 bzero(&pcb->pcb_dbg_regs, sizeof(pcb->pcb_dbg_regs)); 395 } 396 397 int 398 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 399 { 400 struct l_sigframe *frame; 401 ucontext_t uc; 402 struct trapframe *tf; 403 int error; 404 405 tf = td->td_frame; 406 frame = (struct l_sigframe *)tf->tf_sp; 407 408 if (copyin((void *)&frame->uc, &uc, sizeof(uc))) 409 return (EFAULT); 410 411 error = set_mcontext(td, &uc.uc_mcontext); 412 if (error != 0) 413 return (error); 414 415 /* Restore signal mask. */ 416 kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0); 417 418 return (EJUSTRETURN); 419 } 420 421 static void 422 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 423 { 424 struct thread *td; 425 struct proc *p; 426 struct trapframe *tf; 427 struct l_sigframe *fp, *frame; 428 struct l_fpsimd_context *fpsimd; 429 struct l_esr_context *esr; 430 l_stack_t uc_stack; 431 ucontext_t uc; 432 uint8_t *scr; 433 struct sigacts *psp; 434 int onstack, sig, issiginfo; 435 436 td = curthread; 437 p = td->td_proc; 438 PROC_LOCK_ASSERT(p, MA_OWNED); 439 440 sig = ksi->ksi_signo; 441 psp = p->p_sigacts; 442 mtx_assert(&psp->ps_mtx, MA_OWNED); 443 444 tf = td->td_frame; 445 onstack = sigonstack(tf->tf_sp); 446 issiginfo = SIGISMEMBER(psp->ps_siginfo, sig); 447 448 CTR4(KTR_SIG, "sendsig: td=%p (%s) catcher=%p sig=%d", td, p->p_comm, 449 catcher, sig); 450 451 /* Allocate and validate space for the signal handler context. */ 452 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !onstack && 453 SIGISMEMBER(psp->ps_sigonstack, sig)) { 454 fp = (struct l_sigframe *)((uintptr_t)td->td_sigstk.ss_sp + 455 td->td_sigstk.ss_size); 456 #if defined(COMPAT_43) 457 td->td_sigstk.ss_flags |= SS_ONSTACK; 458 #endif 459 } else { 460 fp = (struct l_sigframe *)td->td_frame->tf_sp; 461 } 462 463 /* Make room, keeping the stack aligned */ 464 fp--; 465 fp = (struct l_sigframe *)STACKALIGN(fp); 466 467 get_mcontext(td, &uc.uc_mcontext, 0); 468 uc.uc_sigmask = *mask; 469 470 uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 471 uc_stack.ss_size = td->td_sigstk.ss_size; 472 uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) != 0 ? 473 (onstack ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 474 mtx_unlock(&psp->ps_mtx); 475 PROC_UNLOCK(td->td_proc); 476 477 /* Fill in the frame to copy out */ 478 frame = malloc(sizeof(*frame), M_LINUX, M_WAITOK | M_ZERO); 479 480 memcpy(&frame->sf.sf_uc.uc_sc.regs, tf->tf_x, sizeof(tf->tf_x)); 481 frame->sf.sf_uc.uc_sc.regs[30] = tf->tf_lr; 482 frame->sf.sf_uc.uc_sc.sp = tf->tf_sp; 483 frame->sf.sf_uc.uc_sc.pc = tf->tf_lr; 484 frame->sf.sf_uc.uc_sc.pstate = tf->tf_spsr; 485 frame->sf.sf_uc.uc_sc.fault_address = (register_t)ksi->ksi_addr; 486 487 /* Stack frame for unwinding */ 488 frame->fp = tf->tf_x[29]; 489 frame->lr = tf->tf_lr; 490 491 /* Translate the signal. */ 492 sig = bsd_to_linux_signal(sig); 493 siginfo_to_lsiginfo(&ksi->ksi_info, &frame->sf.sf_si, sig); 494 bsd_to_linux_sigset(mask, &frame->sf.sf_uc.uc_sigmask); 495 496 /* 497 * Prepare fpsimd & esr. Does not check sizes, as 498 * __reserved is big enougth. 499 */ 500 scr = (uint8_t *)&frame->sf.sf_uc.uc_sc.__reserved; 501 #ifdef VFP 502 fpsimd = (struct l_fpsimd_context *) scr; 503 fpsimd->head.magic = L_FPSIMD_MAGIC; 504 fpsimd->head.size = sizeof(struct l_fpsimd_context); 505 fpsimd->fpsr = uc.uc_mcontext.mc_fpregs.fp_sr; 506 fpsimd->fpcr = uc.uc_mcontext.mc_fpregs.fp_cr; 507 508 memcpy(fpsimd->vregs, &uc.uc_mcontext.mc_fpregs.fp_q, 509 sizeof(uc.uc_mcontext.mc_fpregs.fp_q)); 510 scr += roundup(sizeof(struct l_fpsimd_context), 16); 511 #endif 512 if (ksi->ksi_addr != 0) { 513 esr = (struct l_esr_context *) scr; 514 esr->head.magic = L_ESR_MAGIC; 515 esr->head.size = sizeof(struct l_esr_context); 516 esr->esr = tf->tf_esr; 517 } 518 519 memcpy(&frame->sf.sf_uc.uc_stack, &uc_stack, sizeof(uc_stack)); 520 memcpy(&frame->uc, &uc, sizeof(uc)); 521 522 /* Copy the sigframe out to the user's stack. */ 523 if (copyout(frame, fp, sizeof(*fp)) != 0) { 524 /* Process has trashed its stack. Kill it. */ 525 free(frame, M_LINUX); 526 CTR2(KTR_SIG, "sendsig: sigexit td=%p fp=%p", td, fp); 527 PROC_LOCK(p); 528 sigexit(td, SIGILL); 529 } 530 free(frame, M_LINUX); 531 532 tf->tf_x[0]= sig; 533 if (issiginfo) { 534 tf->tf_x[1] = (register_t)&fp->sf.sf_si; 535 tf->tf_x[2] = (register_t)&fp->sf.sf_uc; 536 } else { 537 tf->tf_x[1] = 0; 538 tf->tf_x[2] = 0; 539 } 540 tf->tf_x[8] = (register_t)catcher; 541 tf->tf_sp = (register_t)fp; 542 tf->tf_elr = (register_t)linux_vdso_sigcode; 543 544 CTR3(KTR_SIG, "sendsig: return td=%p pc=%#x sp=%#x", td, tf->tf_elr, 545 tf->tf_sp); 546 547 PROC_LOCK(p); 548 mtx_lock(&psp->ps_mtx); 549 } 550 551 struct sysentvec elf_linux_sysvec = { 552 .sv_size = LINUX_SYS_MAXSYSCALL, 553 .sv_table = linux_sysent, 554 .sv_fixup = linux_elf_fixup, 555 .sv_sendsig = linux_rt_sendsig, 556 .sv_sigcode = &_binary_linux_vdso_so_o_start, 557 .sv_szsigcode = &linux_szsigcode, 558 .sv_name = "Linux ELF64", 559 .sv_coredump = elf64_coredump, 560 .sv_elf_core_osabi = ELFOSABI_NONE, 561 .sv_elf_core_abi_vendor = LINUX_ABI_VENDOR, 562 .sv_elf_core_prepare_notes = linux64_prepare_notes, 563 .sv_imgact_try = linux_exec_imgact_try, 564 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 565 .sv_minuser = VM_MIN_ADDRESS, 566 .sv_maxuser = VM_MAXUSER_ADDRESS, 567 .sv_usrstack = LINUX_USRSTACK, 568 .sv_psstrings = LINUX_PS_STRINGS, 569 .sv_psstringssz = sizeof(struct ps_strings), 570 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE, 571 .sv_copyout_auxargs = linux_copyout_auxargs, 572 .sv_copyout_strings = linux_copyout_strings, 573 .sv_setregs = linux_exec_setregs, 574 .sv_fixlimit = NULL, 575 .sv_maxssiz = NULL, 576 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN | 577 SV_SIG_WAITNDQ | SV_TIMEKEEP, 578 .sv_set_syscall_retval = linux_set_syscall_retval, 579 .sv_fetch_syscall_args = linux_fetch_syscall_args, 580 .sv_syscallnames = linux_syscallnames, 581 .sv_shared_page_base = LINUX_SHAREDPAGE, 582 .sv_shared_page_len = PAGE_SIZE, 583 .sv_schedtail = linux_schedtail, 584 .sv_thread_detach = linux_thread_detach, 585 .sv_trap = NULL, 586 .sv_hwcap = &elf_hwcap, 587 .sv_hwcap2 = &elf_hwcap2, 588 .sv_onexec = linux_on_exec_vmspace, 589 .sv_onexit = linux_on_exit, 590 .sv_ontdexit = linux_thread_dtor, 591 .sv_setid_allowed = &linux_setid_allowed_query, 592 }; 593 594 static int 595 linux_on_exec_vmspace(struct proc *p, struct image_params *imgp) 596 { 597 int error; 598 599 error = linux_map_vdso(p, linux_vdso_obj, linux_vdso_base, 600 LINUX_VDSOPAGE_SIZE, imgp); 601 if (error == 0) 602 linux_on_exec(p, imgp); 603 return (error); 604 } 605 606 /* 607 * linux_vdso_install() and linux_exec_sysvec_init() must be called 608 * after exec_sysvec_init() which is SI_SUB_EXEC (SI_ORDER_ANY). 609 */ 610 static void 611 linux_exec_sysvec_init(void *param) 612 { 613 l_uintptr_t *ktimekeep_base; 614 struct sysentvec *sv; 615 ptrdiff_t tkoff; 616 617 sv = param; 618 /* Fill timekeep_base */ 619 exec_sysvec_init(sv); 620 621 tkoff = kern_timekeep_base - linux_vdso_base; 622 ktimekeep_base = (l_uintptr_t *)(linux_vdso_mapping + tkoff); 623 *ktimekeep_base = sv->sv_shared_page_base + sv->sv_timekeep_offset; 624 } 625 SYSINIT(elf_linux_exec_sysvec_init, SI_SUB_EXEC + 1, SI_ORDER_ANY, 626 linux_exec_sysvec_init, &elf_linux_sysvec); 627 628 static void 629 linux_vdso_install(const void *param) 630 { 631 char *vdso_start = &_binary_linux_vdso_so_o_start; 632 char *vdso_end = &_binary_linux_vdso_so_o_end; 633 634 linux_szsigcode = vdso_end - vdso_start; 635 MPASS(linux_szsigcode <= LINUX_VDSOPAGE_SIZE); 636 637 linux_vdso_base = LINUX_VDSOPAGE; 638 639 __elfN(linux_vdso_fixup)(vdso_start, linux_vdso_base); 640 641 linux_vdso_obj = __elfN(linux_shared_page_init) 642 (&linux_vdso_mapping, LINUX_VDSOPAGE_SIZE); 643 bcopy(vdso_start, linux_vdso_mapping, linux_szsigcode); 644 645 linux_vdso_reloc(linux_vdso_mapping, linux_vdso_base); 646 } 647 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC + 1, SI_ORDER_FIRST, 648 linux_vdso_install, NULL); 649 650 static void 651 linux_vdso_deinstall(const void *param) 652 { 653 654 __elfN(linux_shared_page_fini)(linux_vdso_obj, 655 linux_vdso_mapping, LINUX_VDSOPAGE_SIZE); 656 } 657 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 658 linux_vdso_deinstall, NULL); 659 660 static void 661 linux_vdso_reloc(char *mapping, Elf_Addr offset) 662 { 663 Elf_Size rtype, symidx; 664 const Elf_Rela *rela; 665 const Elf_Shdr *shdr; 666 const Elf_Ehdr *ehdr; 667 Elf_Addr *where; 668 Elf_Addr addr, addend; 669 int i, relacnt; 670 671 MPASS(offset != 0); 672 673 relacnt = 0; 674 ehdr = (const Elf_Ehdr *)mapping; 675 shdr = (const Elf_Shdr *)(mapping + ehdr->e_shoff); 676 for (i = 0; i < ehdr->e_shnum; i++) 677 { 678 switch (shdr[i].sh_type) { 679 case SHT_REL: 680 printf("Linux Aarch64 vDSO: unexpected Rel section\n"); 681 break; 682 case SHT_RELA: 683 rela = (const Elf_Rela *)(mapping + shdr[i].sh_offset); 684 relacnt = shdr[i].sh_size / sizeof(*rela); 685 } 686 } 687 688 for (i = 0; i < relacnt; i++, rela++) { 689 where = (Elf_Addr *)(mapping + rela->r_offset); 690 addend = rela->r_addend; 691 rtype = ELF_R_TYPE(rela->r_info); 692 symidx = ELF_R_SYM(rela->r_info); 693 694 switch (rtype) { 695 case R_AARCH64_NONE: /* none */ 696 break; 697 698 case R_AARCH64_RELATIVE: /* B + A */ 699 addr = (Elf_Addr)(mapping + addend); 700 if (*where != addr) 701 *where = addr; 702 break; 703 default: 704 printf("Linux Aarch64 vDSO: unexpected relocation type %ld, " 705 "symbol index %ld\n", rtype, symidx); 706 } 707 } 708 } 709 710 static char GNU_ABI_VENDOR[] = "GNU"; 711 static int GNU_ABI_LINUX = 0; 712 713 /* LINUXTODO: deduplicate */ 714 static bool 715 linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 716 { 717 const Elf32_Word *desc; 718 uintptr_t p; 719 720 p = (uintptr_t)(note + 1); 721 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 722 723 desc = (const Elf32_Word *)p; 724 if (desc[0] != GNU_ABI_LINUX) 725 return (false); 726 727 *osrel = LINUX_KERNVER(desc[1], desc[2], desc[3]); 728 return (true); 729 } 730 731 static Elf_Brandnote linux64_brandnote = { 732 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 733 .hdr.n_descsz = 16, 734 .hdr.n_type = 1, 735 .vendor = GNU_ABI_VENDOR, 736 .flags = BN_TRANSLATE_OSREL, 737 .trans_osrel = linux_trans_osrel 738 }; 739 740 static Elf64_Brandinfo linux_glibc2brand = { 741 .brand = ELFOSABI_LINUX, 742 .machine = EM_AARCH64, 743 .compat_3_brand = "Linux", 744 .emul_path = linux_emul_path, 745 .interp_path = "/lib64/ld-linux-x86-64.so.2", 746 .sysvec = &elf_linux_sysvec, 747 .interp_newpath = NULL, 748 .brand_note = &linux64_brandnote, 749 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 750 }; 751 752 Elf64_Brandinfo *linux_brandlist[] = { 753 &linux_glibc2brand, 754 NULL 755 }; 756 757 static int 758 linux64_elf_modevent(module_t mod, int type, void *data) 759 { 760 Elf64_Brandinfo **brandinfo; 761 struct linux_ioctl_handler**lihp; 762 int error; 763 764 error = 0; 765 switch(type) { 766 case MOD_LOAD: 767 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 768 ++brandinfo) 769 if (elf64_insert_brand_entry(*brandinfo) < 0) 770 error = EINVAL; 771 if (error == 0) { 772 SET_FOREACH(lihp, linux_ioctl_handler_set) 773 linux_ioctl_register_handler(*lihp); 774 stclohz = (stathz ? stathz : hz); 775 if (bootverbose) 776 printf("Linux arm64 ELF exec handler installed\n"); 777 } 778 break; 779 case MOD_UNLOAD: 780 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 781 ++brandinfo) 782 if (elf64_brand_inuse(*brandinfo)) 783 error = EBUSY; 784 if (error == 0) { 785 for (brandinfo = &linux_brandlist[0]; 786 *brandinfo != NULL; ++brandinfo) 787 if (elf64_remove_brand_entry(*brandinfo) < 0) 788 error = EINVAL; 789 } 790 if (error == 0) { 791 SET_FOREACH(lihp, linux_ioctl_handler_set) 792 linux_ioctl_unregister_handler(*lihp); 793 if (bootverbose) 794 printf("Linux arm64 ELF exec handler removed\n"); 795 } else 796 printf("Could not deinstall Linux arm64 ELF interpreter entry\n"); 797 break; 798 default: 799 return (EOPNOTSUPP); 800 } 801 return (error); 802 } 803 804 static moduledata_t linux64_elf_mod = { 805 "linux64elf", 806 linux64_elf_modevent, 807 0 808 }; 809 810 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 811 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 812 FEATURE(linux64, "AArch64 Linux 64bit support"); 813