1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
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 #define __ELF_WORD_SIZE 64
30
31 #include <sys/param.h>
32 #include <sys/elf.h>
33 #include <sys/exec.h>
34 #include <sys/imgact.h>
35 #include <sys/imgact_elf.h>
36 #include <sys/kernel.h>
37 #include <sys/ktr.h>
38 #include <sys/lock.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 #include <sys/proc.h>
42 #include <sys/stddef.h>
43 #include <sys/syscallsubr.h>
44 #include <sys/sysctl.h>
45 #include <sys/sysent.h>
46
47 #include <vm/vm.h>
48 #include <vm/vm_param.h>
49
50 #include <arm64/linux/linux.h>
51 #include <arm64/linux/linux_proto.h>
52 #include <compat/linux/linux_elf.h>
53 #include <compat/linux/linux_emul.h>
54 #include <compat/linux/linux_fork.h>
55 #include <compat/linux/linux_ioctl.h>
56 #include <compat/linux/linux_mib.h>
57 #include <compat/linux/linux_misc.h>
58 #include <compat/linux/linux_signal.h>
59 #include <compat/linux/linux_util.h>
60 #include <compat/linux/linux_vdso.h>
61
62 #include <arm64/linux/linux_sigframe.h>
63
64 #include <machine/md_var.h>
65 #include <machine/pcb.h>
66 #ifdef VFP
67 #include <machine/vfp.h>
68 #endif
69
70 MODULE_VERSION(linux64elf, 1);
71
72 #define LINUX_VDSOPAGE_SIZE PAGE_SIZE * 2
73 #define LINUX_VDSOPAGE (VM_MAXUSER_ADDRESS - \
74 LINUX_VDSOPAGE_SIZE)
75 #define LINUX_SHAREDPAGE (LINUX_VDSOPAGE - PAGE_SIZE)
76 /*
77 * PAGE_SIZE - the size
78 * of the native SHAREDPAGE
79 */
80 #define LINUX_USRSTACK LINUX_SHAREDPAGE
81 #define LINUX_PS_STRINGS (LINUX_USRSTACK - \
82 sizeof(struct ps_strings))
83
84 static int linux_szsigcode;
85 static vm_object_t linux_vdso_obj;
86 static char *linux_vdso_mapping;
87 extern char _binary_linux_vdso_so_o_start;
88 extern char _binary_linux_vdso_so_o_end;
89 static vm_offset_t linux_vdso_base;
90
91 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL];
92 extern const char *linux_syscallnames[];
93
94 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler);
95
96 static void linux_vdso_install(const void *param);
97 static void linux_vdso_deinstall(const void *param);
98 static void linux_vdso_reloc(char *mapping, Elf_Addr offset);
99 static void linux_set_syscall_retval(struct thread *td, int error);
100 static int linux_fetch_syscall_args(struct thread *td);
101 static void linux_exec_setregs(struct thread *td, struct image_params *imgp,
102 uintptr_t stack);
103 static void linux_exec_sysvec_init(void *param);
104 static int linux_on_exec_vmspace(struct proc *p,
105 struct image_params *imgp);
106
107 LINUX_VDSO_SYM_CHAR(linux_platform);
108 LINUX_VDSO_SYM_INTPTR(kern_timekeep_base);
109 LINUX_VDSO_SYM_INTPTR(__user_rt_sigreturn);
110
111 static int
linux_fetch_syscall_args(struct thread * td)112 linux_fetch_syscall_args(struct thread *td)
113 {
114 struct proc *p;
115 struct syscall_args *sa;
116 register_t *ap;
117
118 p = td->td_proc;
119 ap = td->td_frame->tf_x;
120 sa = &td->td_sa;
121
122 sa->code = td->td_frame->tf_x[8];
123 sa->original_code = sa->code;
124
125 if (sa->code >= p->p_sysent->sv_size)
126 sa->callp = &nosys_sysent;
127 else
128 sa->callp = &p->p_sysent->sv_table[sa->code];
129
130 if (sa->callp->sy_narg > nitems(sa->args))
131 panic("ARM64TODO: Could we have more than %zu args?",
132 nitems(sa->args));
133 memcpy(sa->args, ap, nitems(sa->args) * sizeof(register_t));
134
135 td->td_retval[0] = 0;
136 return (0);
137 }
138
139 static void
linux_set_syscall_retval(struct thread * td,int error)140 linux_set_syscall_retval(struct thread *td, int error)
141 {
142
143 td->td_retval[1] = td->td_frame->tf_x[1];
144 cpu_set_syscall_retval(td, error);
145
146 if (__predict_false(error != 0)) {
147 if (error != ERESTART && error != EJUSTRETURN)
148 td->td_frame->tf_x[0] = bsd_to_linux_errno(error);
149 }
150 }
151
152 void
linux64_arch_copyout_auxargs(struct image_params * imgp,Elf_Auxinfo ** pos)153 linux64_arch_copyout_auxargs(struct image_params *imgp, Elf_Auxinfo **pos)
154 {
155
156 AUXARGS_ENTRY((*pos), LINUX_AT_SYSINFO_EHDR, linux_vdso_base);
157 AUXARGS_ENTRY((*pos), LINUX_AT_HWCAP, *imgp->sysent->sv_hwcap);
158 AUXARGS_ENTRY((*pos), LINUX_AT_HWCAP2, *imgp->sysent->sv_hwcap2);
159 AUXARGS_ENTRY((*pos), LINUX_AT_HWCAP3, *imgp->sysent->sv_hwcap3);
160 AUXARGS_ENTRY((*pos), LINUX_AT_HWCAP4, *imgp->sysent->sv_hwcap4);
161 AUXARGS_ENTRY((*pos), LINUX_AT_PLATFORM, PTROUT(linux_platform));
162 }
163
164 /*
165 * Reset registers to default values on exec.
166 */
167 static void
linux_exec_setregs(struct thread * td,struct image_params * imgp,uintptr_t stack)168 linux_exec_setregs(struct thread *td, struct image_params *imgp,
169 uintptr_t stack)
170 {
171 struct trapframe *regs = td->td_frame;
172 struct pcb *pcb = td->td_pcb;
173
174 memset(regs, 0, sizeof(*regs));
175 regs->tf_sp = stack;
176 regs->tf_elr = imgp->entry_addr;
177 pcb->pcb_tpidr_el0 = 0;
178 pcb->pcb_tpidrro_el0 = 0;
179 WRITE_SPECIALREG(tpidrro_el0, 0);
180 WRITE_SPECIALREG(tpidr_el0, 0);
181
182 #ifdef VFP
183 vfp_reset_state(td, pcb);
184 #endif
185
186 /*
187 * Clear debug register state. It is not applicable to the new process.
188 */
189 bzero(&pcb->pcb_dbg_regs, sizeof(pcb->pcb_dbg_regs));
190 }
191
192 static bool
linux_parse_sigreturn_ctx(struct thread * td,struct l_sigcontext * sc)193 linux_parse_sigreturn_ctx(struct thread *td, struct l_sigcontext *sc)
194 {
195 struct l_fpsimd_context *fpsimd;
196 struct _l_aarch64_ctx *ctx;
197 int offset;
198
199 offset = 0;
200 while (1) {
201 /* The offset must be 16 byte aligned */
202 if ((offset & 15) != 0)
203 return (false);
204
205 /* Check for buffer overflow of the ctx */
206 if ((offset + sizeof(*ctx)) >
207 sizeof(sc->__reserved))
208 return (false);
209
210 ctx = (struct _l_aarch64_ctx *)&sc->__reserved[offset];
211
212 /* Check for buffer overflow of the data */
213 if ((offset + ctx->size) > sizeof(sc->__reserved))
214 return (false);
215
216 switch(ctx->magic) {
217 case 0:
218 if (ctx->size != 0)
219 return (false);
220 return (true);
221 case L_ESR_MAGIC:
222 /* Ignore */
223 break;
224 #ifdef VFP
225 case L_FPSIMD_MAGIC:
226 fpsimd = (struct l_fpsimd_context *)ctx;
227
228 /*
229 * Discard any vfp state for the current thread, we
230 * are about to override it.
231 */
232 critical_enter();
233 vfp_discard(td);
234 critical_exit();
235
236 td->td_pcb->pcb_fpustate.vfp_fpcr = fpsimd->fpcr;
237 td->td_pcb->pcb_fpustate.vfp_fpsr = fpsimd->fpsr;
238 memcpy(td->td_pcb->pcb_fpustate.vfp_regs,
239 fpsimd->vregs, sizeof(fpsimd->vregs));
240
241 break;
242 #endif
243 default:
244 return (false);
245 }
246
247 offset += ctx->size;
248 }
249
250 }
251
252 int
linux_rt_sigreturn(struct thread * td,struct linux_rt_sigreturn_args * args)253 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args)
254 {
255 struct l_rt_sigframe *sf;
256 struct l_sigframe *frame;
257 struct trapframe *tf;
258 sigset_t bmask;
259 int error;
260
261 sf = malloc(sizeof(*sf), M_LINUX, M_WAITOK | M_ZERO);
262
263 tf = td->td_frame;
264 frame = (struct l_sigframe *)tf->tf_sp;
265 error = copyin((void *)&frame->sf, sf, sizeof(*sf));
266 if (error != 0) {
267 free(sf, M_LINUX);
268 return (error);
269 }
270
271 memcpy(tf->tf_x, sf->sf_uc.uc_sc.regs, sizeof(tf->tf_x));
272 tf->tf_lr = sf->sf_uc.uc_sc.regs[30];
273 tf->tf_sp = sf->sf_uc.uc_sc.sp;
274 tf->tf_elr = sf->sf_uc.uc_sc.pc;
275
276 if ((sf->sf_uc.uc_sc.pstate & PSR_M_MASK) != PSR_M_EL0t ||
277 (sf->sf_uc.uc_sc.pstate & PSR_AARCH32) != 0 ||
278 (sf->sf_uc.uc_sc.pstate & PSR_DAIF) !=
279 (td->td_frame->tf_spsr & PSR_DAIF))
280 goto einval;
281 tf->tf_spsr = sf->sf_uc.uc_sc.pstate;
282
283 if (!linux_parse_sigreturn_ctx(td, &sf->sf_uc.uc_sc))
284 goto einval;
285
286 /* Restore signal mask. */
287 linux_to_bsd_sigset(&sf->sf_uc.uc_sigmask, &bmask);
288 kern_sigprocmask(td, SIG_SETMASK, &bmask, NULL, 0);
289 free(sf, M_LINUX);
290
291 return (EJUSTRETURN);
292 einval:
293 free(sf, M_LINUX);
294 return (EINVAL);
295 }
296
297 static void
linux_rt_sendsig(sig_t catcher,ksiginfo_t * ksi,sigset_t * mask)298 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
299 {
300 struct thread *td;
301 struct proc *p;
302 struct trapframe *tf;
303 struct l_sigframe *fp, *frame;
304 struct l_fpsimd_context *fpsimd;
305 struct l_esr_context *esr;
306 l_stack_t uc_stack;
307 ucontext_t uc;
308 uint8_t *scr;
309 struct sigacts *psp;
310 int onstack, sig, issiginfo;
311
312 td = curthread;
313 p = td->td_proc;
314 PROC_LOCK_ASSERT(p, MA_OWNED);
315
316 sig = ksi->ksi_signo;
317 psp = p->p_sigacts;
318 mtx_assert(&psp->ps_mtx, MA_OWNED);
319
320 tf = td->td_frame;
321 onstack = sigonstack(tf->tf_sp);
322 issiginfo = SIGISMEMBER(psp->ps_siginfo, sig);
323
324 CTR4(KTR_SIG, "sendsig: td=%p (%s) catcher=%p sig=%d", td, p->p_comm,
325 catcher, sig);
326
327 /* Allocate and validate space for the signal handler context. */
328 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !onstack &&
329 SIGISMEMBER(psp->ps_sigonstack, sig)) {
330 fp = (struct l_sigframe *)((uintptr_t)td->td_sigstk.ss_sp +
331 td->td_sigstk.ss_size);
332 #if defined(COMPAT_43)
333 td->td_sigstk.ss_flags |= SS_ONSTACK;
334 #endif
335 } else {
336 fp = (struct l_sigframe *)td->td_frame->tf_sp;
337 }
338
339 /* Make room, keeping the stack aligned */
340 fp--;
341 fp = (struct l_sigframe *)STACKALIGN(fp);
342
343 get_mcontext(td, &uc.uc_mcontext, 0);
344 uc.uc_sigmask = *mask;
345
346 uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp);
347 uc_stack.ss_size = td->td_sigstk.ss_size;
348 uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) != 0 ?
349 (onstack ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE;
350 mtx_unlock(&psp->ps_mtx);
351 PROC_UNLOCK(td->td_proc);
352
353 /* Fill in the frame to copy out */
354 frame = malloc(sizeof(*frame), M_LINUX, M_WAITOK | M_ZERO);
355
356 memcpy(&frame->sf.sf_uc.uc_sc.regs, tf->tf_x, sizeof(tf->tf_x));
357 frame->sf.sf_uc.uc_sc.regs[30] = tf->tf_lr;
358 frame->sf.sf_uc.uc_sc.sp = tf->tf_sp;
359 frame->sf.sf_uc.uc_sc.pc = tf->tf_elr;
360 frame->sf.sf_uc.uc_sc.pstate = tf->tf_spsr;
361 frame->sf.sf_uc.uc_sc.fault_address = (register_t)ksi->ksi_addr;
362
363 /* Stack frame for unwinding */
364 frame->fp = tf->tf_x[29];
365 frame->lr = tf->tf_elr;
366
367 /* Translate the signal. */
368 sig = bsd_to_linux_signal(sig);
369 siginfo_to_lsiginfo(&ksi->ksi_info, &frame->sf.sf_si, sig);
370 bsd_to_linux_sigset(mask, &frame->sf.sf_uc.uc_sigmask);
371
372 /*
373 * Prepare fpsimd & esr. Does not check sizes, as
374 * __reserved is big enougth.
375 */
376 scr = (uint8_t *)&frame->sf.sf_uc.uc_sc.__reserved;
377 #ifdef VFP
378 fpsimd = (struct l_fpsimd_context *) scr;
379 fpsimd->head.magic = L_FPSIMD_MAGIC;
380 fpsimd->head.size = sizeof(struct l_fpsimd_context);
381 fpsimd->fpsr = uc.uc_mcontext.mc_fpregs.fp_sr;
382 fpsimd->fpcr = uc.uc_mcontext.mc_fpregs.fp_cr;
383
384 memcpy(fpsimd->vregs, &uc.uc_mcontext.mc_fpregs.fp_q,
385 sizeof(uc.uc_mcontext.mc_fpregs.fp_q));
386 scr += roundup(sizeof(struct l_fpsimd_context), 16);
387 #endif
388 if (ksi->ksi_addr != 0) {
389 esr = (struct l_esr_context *) scr;
390 esr->head.magic = L_ESR_MAGIC;
391 esr->head.size = sizeof(struct l_esr_context);
392 esr->esr = tf->tf_esr;
393 }
394
395 memcpy(&frame->sf.sf_uc.uc_stack, &uc_stack, sizeof(uc_stack));
396
397 /* Copy the sigframe out to the user's stack. */
398 if (copyout(frame, fp, sizeof(*fp)) != 0) {
399 /* Process has trashed its stack. Kill it. */
400 free(frame, M_LINUX);
401 CTR2(KTR_SIG, "sendsig: sigexit td=%p fp=%p", td, fp);
402 PROC_LOCK(p);
403 sigexit(td, SIGILL);
404 }
405 free(frame, M_LINUX);
406
407 tf->tf_x[0]= sig;
408 if (issiginfo) {
409 tf->tf_x[1] = (register_t)&fp->sf.sf_si;
410 tf->tf_x[2] = (register_t)&fp->sf.sf_uc;
411 } else {
412 tf->tf_x[1] = 0;
413 tf->tf_x[2] = 0;
414 }
415 tf->tf_x[29] = (register_t)&fp->fp;
416 tf->tf_elr = (register_t)catcher;
417 tf->tf_sp = (register_t)fp;
418 tf->tf_lr = (register_t)__user_rt_sigreturn;
419
420 CTR3(KTR_SIG, "sendsig: return td=%p pc=%#x sp=%#x", td, tf->tf_elr,
421 tf->tf_sp);
422
423 PROC_LOCK(p);
424 mtx_lock(&psp->ps_mtx);
425 }
426
427 struct sysentvec elf_linux_sysvec = {
428 .sv_size = LINUX_SYS_MAXSYSCALL,
429 .sv_table = linux_sysent,
430 .sv_fixup = __elfN(freebsd_fixup),
431 .sv_sendsig = linux_rt_sendsig,
432 .sv_sigcode = &_binary_linux_vdso_so_o_start,
433 .sv_szsigcode = &linux_szsigcode,
434 .sv_name = "Linux ELF64",
435 .sv_coredump = elf64_coredump,
436 .sv_elf_core_osabi = ELFOSABI_NONE,
437 .sv_elf_core_abi_vendor = LINUX_ABI_VENDOR,
438 .sv_elf_core_prepare_notes = linux64_prepare_notes,
439 .sv_minsigstksz = LINUX_MINSIGSTKSZ,
440 .sv_minuser = VM_MIN_ADDRESS,
441 .sv_maxuser = VM_MAXUSER_ADDRESS,
442 .sv_usrstack = LINUX_USRSTACK,
443 .sv_psstrings = LINUX_PS_STRINGS,
444 .sv_psstringssz = sizeof(struct ps_strings),
445 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE,
446 .sv_copyout_auxargs = __linuxN(copyout_auxargs),
447 .sv_copyout_strings = __linuxN(copyout_strings),
448 .sv_setregs = linux_exec_setregs,
449 .sv_fixlimit = NULL,
450 .sv_maxssiz = NULL,
451 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN |
452 SV_SIG_WAITNDQ | SV_TIMEKEEP,
453 .sv_set_syscall_retval = linux_set_syscall_retval,
454 .sv_fetch_syscall_args = linux_fetch_syscall_args,
455 .sv_syscallnames = linux_syscallnames,
456 .sv_shared_page_base = LINUX_SHAREDPAGE,
457 .sv_shared_page_len = PAGE_SIZE,
458 .sv_schedtail = linux_schedtail,
459 .sv_thread_detach = linux_thread_detach,
460 .sv_trap = NULL,
461 .sv_hwcap = &linux_elf_hwcap,
462 .sv_hwcap2 = &linux_elf_hwcap2,
463 .sv_hwcap3 = &linux_elf_hwcap3,
464 .sv_hwcap4 = &linux_elf_hwcap4,
465 .sv_onexec = linux_on_exec_vmspace,
466 .sv_onexit = linux_on_exit,
467 .sv_ontdexit = linux_thread_dtor,
468 .sv_setid_allowed = &linux_setid_allowed_query,
469 };
470
471 static int
linux_on_exec_vmspace(struct proc * p,struct image_params * imgp)472 linux_on_exec_vmspace(struct proc *p, struct image_params *imgp)
473 {
474 int error;
475
476 error = linux_map_vdso(p, linux_vdso_obj, linux_vdso_base,
477 LINUX_VDSOPAGE_SIZE, imgp);
478 if (error == 0)
479 error = linux_on_exec(p, imgp);
480 return (error);
481 }
482
483 /*
484 * linux_vdso_install() and linux_exec_sysvec_init() must be called
485 * after exec_sysvec_init() which is SI_SUB_EXEC (SI_ORDER_ANY).
486 */
487 static void
linux_exec_sysvec_init(void * param)488 linux_exec_sysvec_init(void *param)
489 {
490 l_uintptr_t *ktimekeep_base;
491 struct sysentvec *sv;
492 ptrdiff_t tkoff;
493
494 sv = param;
495 /* Fill timekeep_base */
496 exec_sysvec_init(sv);
497
498 tkoff = kern_timekeep_base - linux_vdso_base;
499 ktimekeep_base = (l_uintptr_t *)(linux_vdso_mapping + tkoff);
500 *ktimekeep_base = sv->sv_shared_page_base + sv->sv_timekeep_offset;
501 }
502 SYSINIT(elf_linux_exec_sysvec_init, SI_SUB_EXEC + 1, SI_ORDER_ANY,
503 linux_exec_sysvec_init, &elf_linux_sysvec);
504
505 static void
linux_vdso_install(const void * param)506 linux_vdso_install(const void *param)
507 {
508 char *vdso_start = &_binary_linux_vdso_so_o_start;
509 char *vdso_end = &_binary_linux_vdso_so_o_end;
510
511 linux_szsigcode = vdso_end - vdso_start;
512 MPASS(linux_szsigcode <= LINUX_VDSOPAGE_SIZE);
513
514 linux_vdso_base = LINUX_VDSOPAGE;
515
516 __elfN(linux_vdso_fixup)(vdso_start, linux_vdso_base);
517
518 linux_vdso_obj = __elfN(linux_shared_page_init)
519 (&linux_vdso_mapping, LINUX_VDSOPAGE_SIZE);
520 bcopy(vdso_start, linux_vdso_mapping, linux_szsigcode);
521
522 linux_vdso_reloc(linux_vdso_mapping, linux_vdso_base);
523 }
524 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC + 1, SI_ORDER_FIRST,
525 linux_vdso_install, NULL);
526
527 static void
linux_vdso_deinstall(const void * param)528 linux_vdso_deinstall(const void *param)
529 {
530
531 __elfN(linux_shared_page_fini)(linux_vdso_obj,
532 linux_vdso_mapping, LINUX_VDSOPAGE_SIZE);
533 }
534 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST,
535 linux_vdso_deinstall, NULL);
536
537 static void
linux_vdso_reloc(char * mapping,Elf_Addr offset)538 linux_vdso_reloc(char *mapping, Elf_Addr offset)
539 {
540 Elf_Size rtype, symidx;
541 const Elf_Rela *rela;
542 const Elf_Shdr *shdr;
543 const Elf_Ehdr *ehdr;
544 Elf_Addr *where;
545 Elf_Addr addr, addend;
546 int i, relacnt;
547
548 MPASS(offset != 0);
549
550 relacnt = 0;
551 ehdr = (const Elf_Ehdr *)mapping;
552 shdr = (const Elf_Shdr *)(mapping + ehdr->e_shoff);
553 for (i = 0; i < ehdr->e_shnum; i++)
554 {
555 switch (shdr[i].sh_type) {
556 case SHT_REL:
557 printf("Linux Aarch64 vDSO: unexpected Rel section\n");
558 break;
559 case SHT_RELA:
560 rela = (const Elf_Rela *)(mapping + shdr[i].sh_offset);
561 relacnt = shdr[i].sh_size / sizeof(*rela);
562 }
563 }
564
565 for (i = 0; i < relacnt; i++, rela++) {
566 where = (Elf_Addr *)(mapping + rela->r_offset);
567 addend = rela->r_addend;
568 rtype = ELF_R_TYPE(rela->r_info);
569 symidx = ELF_R_SYM(rela->r_info);
570
571 switch (rtype) {
572 case R_AARCH64_NONE: /* none */
573 break;
574
575 case R_AARCH64_RELATIVE: /* B + A */
576 addr = (Elf_Addr)(mapping + addend);
577 if (*where != addr)
578 *where = addr;
579 break;
580 default:
581 printf("Linux Aarch64 vDSO: unexpected relocation type %ld, "
582 "symbol index %ld\n", rtype, symidx);
583 }
584 }
585 }
586
587 static Elf_Brandnote linux64_brandnote = {
588 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR),
589 .hdr.n_descsz = 16,
590 .hdr.n_type = 1,
591 .vendor = GNU_ABI_VENDOR,
592 .flags = BN_TRANSLATE_OSREL,
593 .trans_osrel = linux_trans_osrel
594 };
595
596 static Elf64_Brandinfo linux_glibc2brand = {
597 .brand = ELFOSABI_LINUX,
598 .machine = EM_AARCH64,
599 .compat_3_brand = "Linux",
600 .interp_path = "/lib64/ld-linux-x86-64.so.2",
601 .sysvec = &elf_linux_sysvec,
602 .interp_newpath = NULL,
603 .brand_note = &linux64_brandnote,
604 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
605 };
606
607 Elf64_Brandinfo *linux_brandlist[] = {
608 &linux_glibc2brand,
609 NULL
610 };
611
612 static int
linux64_elf_modevent(module_t mod,int type,void * data)613 linux64_elf_modevent(module_t mod, int type, void *data)
614 {
615 Elf64_Brandinfo **brandinfo;
616 struct linux_ioctl_handler**lihp;
617 int error;
618
619 error = 0;
620 switch(type) {
621 case MOD_LOAD:
622 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL;
623 ++brandinfo)
624 if (elf64_insert_brand_entry(*brandinfo) < 0)
625 error = EINVAL;
626 if (error == 0) {
627 SET_FOREACH(lihp, linux_ioctl_handler_set)
628 linux_ioctl_register_handler(*lihp);
629 stclohz = (stathz ? stathz : hz);
630 if (bootverbose)
631 printf("Linux arm64 ELF exec handler installed\n");
632 }
633 break;
634 case MOD_UNLOAD:
635 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL;
636 ++brandinfo)
637 if (elf64_brand_inuse(*brandinfo))
638 error = EBUSY;
639 if (error == 0) {
640 for (brandinfo = &linux_brandlist[0];
641 *brandinfo != NULL; ++brandinfo)
642 if (elf64_remove_brand_entry(*brandinfo) < 0)
643 error = EINVAL;
644 }
645 if (error == 0) {
646 SET_FOREACH(lihp, linux_ioctl_handler_set)
647 linux_ioctl_unregister_handler(*lihp);
648 if (bootverbose)
649 printf("Linux arm64 ELF exec handler removed\n");
650 } else
651 printf("Could not deinstall Linux arm64 ELF interpreter entry\n");
652 break;
653 default:
654 return (EOPNOTSUPP);
655 }
656 return (error);
657 }
658
659 static moduledata_t linux64_elf_mod = {
660 "linux64elf",
661 linux64_elf_modevent,
662 0
663 };
664
665 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY);
666 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1);
667 FEATURE(linux64, "AArch64 Linux 64bit support");
668