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