1 /*- 2 * Copyright (c) 2004 Tim J. Robbins 3 * Copyright (c) 2003 Peter Wemm 4 * Copyright (c) 2002 Doug Rabson 5 * Copyright (c) 1998-1999 Andrew Gallatin 6 * Copyright (c) 1994-1996 Søren Schmidt 7 * All rights reserved. 8 * Copyright (c) 2013, 2021 Dmitry Chagin <dchagin@FreeBSD.org> 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 #define __ELF_WORD_SIZE 64 38 39 #include <sys/param.h> 40 #include <sys/exec.h> 41 #include <sys/imgact.h> 42 #include <sys/imgact_elf.h> 43 #include <sys/kernel.h> 44 #include <sys/ktr.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/module.h> 48 #include <sys/mutex.h> 49 #include <sys/proc.h> 50 #include <sys/stddef.h> 51 #include <sys/syscallsubr.h> 52 #include <sys/sysctl.h> 53 #include <sys/sysent.h> 54 55 #include <vm/pmap.h> 56 #include <vm/vm.h> 57 #include <vm/vm_map.h> 58 #include <vm/vm_page.h> 59 60 #include <machine/cpu.h> 61 #include <machine/md_var.h> 62 #include <machine/pcb.h> 63 #include <machine/specialreg.h> 64 #include <machine/trap.h> 65 66 #include <x86/linux/linux_x86.h> 67 #include <amd64/linux/linux.h> 68 #include <amd64/linux/linux_proto.h> 69 #include <compat/linux/linux_elf.h> 70 #include <compat/linux/linux_emul.h> 71 #include <compat/linux/linux_fork.h> 72 #include <compat/linux/linux_ioctl.h> 73 #include <compat/linux/linux_mib.h> 74 #include <compat/linux/linux_misc.h> 75 #include <compat/linux/linux_signal.h> 76 #include <compat/linux/linux_sysproto.h> 77 #include <compat/linux/linux_util.h> 78 #include <compat/linux/linux_vdso.h> 79 80 #include <x86/linux/linux_x86_sigframe.h> 81 82 MODULE_VERSION(linux64, 1); 83 84 #define LINUX_VDSOPAGE_SIZE PAGE_SIZE * 2 85 #define LINUX_VDSOPAGE_LA48 (VM_MAXUSER_ADDRESS_LA48 - \ 86 LINUX_VDSOPAGE_SIZE) 87 #define LINUX_SHAREDPAGE_LA48 (LINUX_VDSOPAGE_LA48 - PAGE_SIZE) 88 /* 89 * PAGE_SIZE - the size 90 * of the native SHAREDPAGE 91 */ 92 #define LINUX_USRSTACK_LA48 LINUX_SHAREDPAGE_LA48 93 #define LINUX_PS_STRINGS_LA48 (LINUX_USRSTACK_LA48 - \ 94 sizeof(struct ps_strings)) 95 96 static int linux_szsigcode; 97 static vm_object_t linux_vdso_obj; 98 static char *linux_vdso_mapping; 99 extern char _binary_linux_vdso_so_o_start; 100 extern char _binary_linux_vdso_so_o_end; 101 static vm_offset_t linux_vdso_base; 102 103 extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 104 extern const char *linux_syscallnames[]; 105 106 SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 107 108 static void linux_vdso_install(const void *param); 109 static void linux_vdso_deinstall(const void *param); 110 static void linux_vdso_reloc(char *mapping, Elf_Addr offset); 111 static void linux_set_syscall_retval(struct thread *td, int error); 112 static int linux_fetch_syscall_args(struct thread *td); 113 static void linux_exec_setregs(struct thread *td, struct image_params *imgp, 114 uintptr_t stack); 115 static void linux_exec_sysvec_init(void *param); 116 static int linux_on_exec_vmspace(struct proc *p, 117 struct image_params *imgp); 118 static void linux_set_fork_retval(struct thread *td); 119 static int linux_vsyscall(struct thread *td); 120 121 LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 122 LINUX_VDSO_SYM_CHAR(linux_platform); 123 LINUX_VDSO_SYM_INTPTR(kern_timekeep_base); 124 LINUX_VDSO_SYM_INTPTR(kern_tsc_selector); 125 LINUX_VDSO_SYM_INTPTR(kern_cpu_selector); 126 127 static int 128 linux_fetch_syscall_args(struct thread *td) 129 { 130 struct proc *p; 131 struct trapframe *frame; 132 struct syscall_args *sa; 133 134 p = td->td_proc; 135 frame = td->td_frame; 136 sa = &td->td_sa; 137 138 sa->args[0] = frame->tf_rdi; 139 sa->args[1] = frame->tf_rsi; 140 sa->args[2] = frame->tf_rdx; 141 sa->args[3] = frame->tf_rcx; 142 sa->args[4] = frame->tf_r8; 143 sa->args[5] = frame->tf_r9; 144 sa->code = frame->tf_rax; 145 sa->original_code = sa->code; 146 147 if (sa->code >= p->p_sysent->sv_size) 148 /* nosys */ 149 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 150 else 151 sa->callp = &p->p_sysent->sv_table[sa->code]; 152 153 td->td_retval[0] = 0; 154 return (0); 155 } 156 157 static void 158 linux_set_syscall_retval(struct thread *td, int error) 159 { 160 struct trapframe *frame; 161 162 frame = td->td_frame; 163 164 switch (error) { 165 case 0: 166 frame->tf_rax = td->td_retval[0]; 167 frame->tf_r10 = frame->tf_rcx; 168 break; 169 170 case ERESTART: 171 /* 172 * Reconstruct pc, we know that 'syscall' is 2 bytes, 173 * lcall $X,y is 7 bytes, int 0x80 is 2 bytes. 174 * We saved this in tf_err. 175 * 176 */ 177 frame->tf_rip -= frame->tf_err; 178 frame->tf_r10 = frame->tf_rcx; 179 break; 180 181 case EJUSTRETURN: 182 break; 183 184 default: 185 frame->tf_rax = bsd_to_linux_errno(error); 186 frame->tf_r10 = frame->tf_rcx; 187 break; 188 } 189 190 /* 191 * Differently from FreeBSD native ABI, on Linux only %rcx 192 * and %r11 values are not preserved across the syscall. 193 * Require full context restore to get all registers except 194 * those two restored at return to usermode. 195 * 196 * XXX: Would be great to be able to avoid PCB_FULL_IRET 197 * for the error == 0 case. 198 */ 199 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 200 } 201 202 static void 203 linux_set_fork_retval(struct thread *td) 204 { 205 struct trapframe *frame = td->td_frame; 206 207 frame->tf_rax = 0; 208 } 209 210 static int 211 linux_copyout_auxargs(struct image_params *imgp, uintptr_t base) 212 { 213 Elf_Auxargs *args; 214 Elf_Auxinfo *argarray, *pos; 215 struct proc *p; 216 int error, issetugid; 217 218 p = imgp->proc; 219 args = (Elf64_Auxargs *)imgp->auxargs; 220 argarray = pos = malloc(LINUX_AT_COUNT * sizeof(*pos), M_TEMP, 221 M_WAITOK | M_ZERO); 222 223 issetugid = p->p_flag & P_SUGID ? 1 : 0; 224 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, linux_vdso_base); 225 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 226 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 227 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 228 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 229 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 230 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 231 AUXARGS_ENTRY(pos, AT_BASE, args->base); 232 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 233 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 234 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 235 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 236 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 237 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 238 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, issetugid); 239 AUXARGS_ENTRY_PTR(pos, LINUX_AT_RANDOM, imgp->canary); 240 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP2, 0); 241 if (imgp->execpathp != 0) 242 AUXARGS_ENTRY_PTR(pos, LINUX_AT_EXECFN, imgp->execpathp); 243 if (args->execfd != -1) 244 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 245 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 246 AUXARGS_ENTRY(pos, AT_NULL, 0); 247 248 free(imgp->auxargs, M_TEMP); 249 imgp->auxargs = NULL; 250 KASSERT(pos - argarray <= LINUX_AT_COUNT, ("Too many auxargs")); 251 252 error = copyout(argarray, (void *)base, 253 sizeof(*argarray) * LINUX_AT_COUNT); 254 free(argarray, M_TEMP); 255 return (error); 256 } 257 258 /* 259 * Reset registers to default values on exec. 260 */ 261 static void 262 linux_exec_setregs(struct thread *td, struct image_params *imgp, 263 uintptr_t stack) 264 { 265 struct trapframe *regs; 266 struct pcb *pcb; 267 register_t saved_rflags; 268 269 regs = td->td_frame; 270 pcb = td->td_pcb; 271 272 if (td->td_proc->p_md.md_ldt != NULL) 273 user_ldt_free(td); 274 275 pcb->pcb_fsbase = 0; 276 pcb->pcb_gsbase = 0; 277 clear_pcb_flags(pcb, PCB_32BIT); 278 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 279 set_pcb_flags(pcb, PCB_FULL_IRET); 280 281 saved_rflags = regs->tf_rflags & PSL_T; 282 bzero((char *)regs, sizeof(struct trapframe)); 283 regs->tf_rip = imgp->entry_addr; 284 regs->tf_rsp = stack; 285 regs->tf_rflags = PSL_USER | saved_rflags; 286 regs->tf_ss = _udatasel; 287 regs->tf_cs = _ucodesel; 288 regs->tf_ds = _udatasel; 289 regs->tf_es = _udatasel; 290 regs->tf_fs = _ufssel; 291 regs->tf_gs = _ugssel; 292 regs->tf_flags = TF_HASSEGS; 293 294 x86_clear_dbregs(pcb); 295 296 /* 297 * Drop the FP state if we hold it, so that the process gets a 298 * clean FP state if it uses the FPU again. 299 */ 300 fpstate_drop(td); 301 } 302 303 /* 304 * Copied from amd64/amd64/machdep.c 305 */ 306 int 307 linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 308 { 309 struct proc *p; 310 struct l_rt_sigframe sf; 311 struct l_sigcontext *context; 312 struct trapframe *regs; 313 mcontext_t mc; 314 unsigned long rflags; 315 sigset_t bmask; 316 int error, i; 317 ksiginfo_t ksi; 318 319 regs = td->td_frame; 320 error = copyin((void *)regs->tf_rbx, &sf, sizeof(sf)); 321 if (error != 0) 322 return (error); 323 324 p = td->td_proc; 325 context = &sf.sf_uc.uc_mcontext; 326 rflags = context->sc_rflags; 327 328 /* 329 * Don't allow users to change privileged or reserved flags. 330 */ 331 /* 332 * XXX do allow users to change the privileged flag PSL_RF. 333 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 334 * should sometimes set it there too. tf_rflags is kept in 335 * the signal context during signal handling and there is no 336 * other place to remember it, so the PSL_RF bit may be 337 * corrupted by the signal handler without us knowing. 338 * Corruption of the PSL_RF bit at worst causes one more or 339 * one less debugger trap, so allowing it is fairly harmless. 340 */ 341 if (!EFL_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 342 uprintf("pid %d comm %s linux mangled rflags %#lx\n", 343 p->p_pid, p->p_comm, rflags); 344 return (EINVAL); 345 } 346 347 /* 348 * Don't allow users to load a valid privileged %cs. Let the 349 * hardware check for invalid selectors, excess privilege in 350 * other selectors, invalid %eip's and invalid %esp's. 351 */ 352 if (!CS_SECURE(context->sc_cs)) { 353 uprintf("pid %d comm %s linux mangled cs %#x\n", 354 p->p_pid, p->p_comm, context->sc_cs); 355 ksiginfo_init_trap(&ksi); 356 ksi.ksi_signo = SIGBUS; 357 ksi.ksi_code = BUS_OBJERR; 358 ksi.ksi_trapno = T_PROTFLT; 359 ksi.ksi_addr = (void *)regs->tf_rip; 360 trapsignal(td, &ksi); 361 return (EINVAL); 362 } 363 364 linux_to_bsd_sigset(&sf.sf_uc.uc_sigmask, &bmask); 365 kern_sigprocmask(td, SIG_SETMASK, &bmask, NULL, 0); 366 367 regs->tf_rdi = context->sc_rdi; 368 regs->tf_rsi = context->sc_rsi; 369 regs->tf_rdx = context->sc_rdx; 370 regs->tf_rbp = context->sc_rbp; 371 regs->tf_rbx = context->sc_rbx; 372 regs->tf_rcx = context->sc_rcx; 373 regs->tf_rax = context->sc_rax; 374 regs->tf_rip = context->sc_rip; 375 regs->tf_rsp = context->sc_rsp; 376 regs->tf_r8 = context->sc_r8; 377 regs->tf_r9 = context->sc_r9; 378 regs->tf_r10 = context->sc_r10; 379 regs->tf_r11 = context->sc_r11; 380 regs->tf_r12 = context->sc_r12; 381 regs->tf_r13 = context->sc_r13; 382 regs->tf_r14 = context->sc_r14; 383 regs->tf_r15 = context->sc_r15; 384 regs->tf_cs = context->sc_cs; 385 regs->tf_err = context->sc_err; 386 regs->tf_rflags = rflags; 387 388 if (sf.sf_uc.uc_mcontext.sc_fpstate != NULL) { 389 struct savefpu *svfp = (struct savefpu *)mc.mc_fpstate; 390 391 bzero(&mc, sizeof(mc)); 392 mc.mc_ownedfp = _MC_FPOWNED_FPU; 393 mc.mc_fpformat = _MC_FPFMT_XMM; 394 395 svfp->sv_env.en_cw = sf.sf_fs.cwd; 396 svfp->sv_env.en_sw = sf.sf_fs.swd; 397 svfp->sv_env.en_tw = sf.sf_fs.twd; 398 svfp->sv_env.en_opcode = sf.sf_fs.fop; 399 svfp->sv_env.en_rip = sf.sf_fs.rip; 400 svfp->sv_env.en_rdp = sf.sf_fs.rdp; 401 svfp->sv_env.en_mxcsr = sf.sf_fs.mxcsr; 402 svfp->sv_env.en_mxcsr_mask = sf.sf_fs.mxcsr_mask; 403 /* FPU registers */ 404 for (i = 0; i < nitems(svfp->sv_fp); ++i) 405 bcopy(&sf.sf_fs.st[i], svfp->sv_fp[i].fp_acc.fp_bytes, 406 sizeof(svfp->sv_fp[i].fp_acc.fp_bytes)); 407 /* SSE registers */ 408 for (i = 0; i < nitems(svfp->sv_xmm); ++i) 409 bcopy(&sf.sf_fs.xmm[i], svfp->sv_xmm[i].xmm_bytes, 410 sizeof(svfp->sv_xmm[i].xmm_bytes)); 411 error = set_fpcontext(td, &mc, NULL, 0); 412 if (error != 0) { 413 uprintf("pid %d comm %s linux can't restore fpu state %d\n", 414 p->p_pid, p->p_comm, error); 415 return (error); 416 } 417 } 418 419 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 420 return (EJUSTRETURN); 421 } 422 423 /* 424 * copied from amd64/amd64/machdep.c 425 * 426 * Send an interrupt to process. 427 */ 428 static void 429 linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 430 { 431 struct l_rt_sigframe sf, *sfp; 432 struct proc *p; 433 struct thread *td; 434 struct sigacts *psp; 435 caddr_t sp; 436 struct trapframe *regs; 437 struct savefpu *svfp; 438 mcontext_t mc; 439 int sig, code; 440 int oonstack, issiginfo, i; 441 442 td = curthread; 443 p = td->td_proc; 444 PROC_LOCK_ASSERT(p, MA_OWNED); 445 sig = linux_translate_traps(ksi->ksi_signo, ksi->ksi_trapno); 446 psp = p->p_sigacts; 447 issiginfo = SIGISMEMBER(psp->ps_siginfo, sig); 448 code = ksi->ksi_code; 449 mtx_assert(&psp->ps_mtx, MA_OWNED); 450 regs = td->td_frame; 451 oonstack = sigonstack(regs->tf_rsp); 452 453 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 454 catcher, sig, mask, code); 455 456 bzero(&sf, sizeof(sf)); 457 sf.sf_uc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 458 sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size; 459 sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 460 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 461 462 /* Allocate space for the signal handler context. */ 463 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 464 SIGISMEMBER(psp->ps_sigonstack, sig)) { 465 sp = (caddr_t)td->td_sigstk.ss_sp + td->td_sigstk.ss_size; 466 } else 467 sp = (caddr_t)regs->tf_rsp - 128; 468 469 mtx_unlock(&psp->ps_mtx); 470 PROC_UNLOCK(p); 471 472 /* Make room, keeping the stack aligned. */ 473 sp -= sizeof(struct l_rt_sigframe); 474 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 475 476 /* Save user context. */ 477 bsd_to_linux_sigset(mask, &sf.sf_uc.uc_sigmask); 478 sf.sf_uc.uc_mcontext.sc_mask = sf.sf_uc.uc_sigmask; 479 sf.sf_uc.uc_mcontext.sc_rdi = regs->tf_rdi; 480 sf.sf_uc.uc_mcontext.sc_rsi = regs->tf_rsi; 481 sf.sf_uc.uc_mcontext.sc_rdx = regs->tf_rdx; 482 sf.sf_uc.uc_mcontext.sc_rbp = regs->tf_rbp; 483 sf.sf_uc.uc_mcontext.sc_rbx = regs->tf_rbx; 484 sf.sf_uc.uc_mcontext.sc_rcx = regs->tf_rcx; 485 sf.sf_uc.uc_mcontext.sc_rax = regs->tf_rax; 486 sf.sf_uc.uc_mcontext.sc_rip = regs->tf_rip; 487 sf.sf_uc.uc_mcontext.sc_rsp = regs->tf_rsp; 488 sf.sf_uc.uc_mcontext.sc_r8 = regs->tf_r8; 489 sf.sf_uc.uc_mcontext.sc_r9 = regs->tf_r9; 490 sf.sf_uc.uc_mcontext.sc_r10 = regs->tf_r10; 491 sf.sf_uc.uc_mcontext.sc_r11 = regs->tf_r11; 492 sf.sf_uc.uc_mcontext.sc_r12 = regs->tf_r12; 493 sf.sf_uc.uc_mcontext.sc_r13 = regs->tf_r13; 494 sf.sf_uc.uc_mcontext.sc_r14 = regs->tf_r14; 495 sf.sf_uc.uc_mcontext.sc_r15 = regs->tf_r15; 496 sf.sf_uc.uc_mcontext.sc_cs = regs->tf_cs; 497 sf.sf_uc.uc_mcontext.sc_rflags = regs->tf_rflags; 498 sf.sf_uc.uc_mcontext.sc_err = regs->tf_err; 499 sf.sf_uc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 500 sf.sf_uc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 501 502 get_fpcontext(td, &mc, NULL, NULL); 503 KASSERT(mc.mc_fpformat != _MC_FPFMT_NODEV, ("fpu not present")); 504 svfp = (struct savefpu *)mc.mc_fpstate; 505 506 sf.sf_fs.cwd = svfp->sv_env.en_cw; 507 sf.sf_fs.swd = svfp->sv_env.en_sw; 508 sf.sf_fs.twd = svfp->sv_env.en_tw; 509 sf.sf_fs.fop = svfp->sv_env.en_opcode; 510 sf.sf_fs.rip = svfp->sv_env.en_rip; 511 sf.sf_fs.rdp = svfp->sv_env.en_rdp; 512 sf.sf_fs.mxcsr = svfp->sv_env.en_mxcsr; 513 sf.sf_fs.mxcsr_mask = svfp->sv_env.en_mxcsr_mask; 514 /* FPU registers */ 515 for (i = 0; i < nitems(svfp->sv_fp); ++i) 516 bcopy(svfp->sv_fp[i].fp_acc.fp_bytes, &sf.sf_fs.st[i], 517 sizeof(svfp->sv_fp[i].fp_acc.fp_bytes)); 518 /* SSE registers */ 519 for (i = 0; i < nitems(svfp->sv_xmm); ++i) 520 bcopy(svfp->sv_xmm[i].xmm_bytes, &sf.sf_fs.xmm[i], 521 sizeof(svfp->sv_xmm[i].xmm_bytes)); 522 sf.sf_uc.uc_mcontext.sc_fpstate = (struct l_fpstate *)((caddr_t)sfp + 523 offsetof(struct l_rt_sigframe, sf_fs)); 524 525 /* Translate the signal. */ 526 sig = bsd_to_linux_signal(sig); 527 /* Fill in POSIX parts. */ 528 siginfo_to_lsiginfo(&ksi->ksi_info, &sf.sf_si, sig); 529 530 /* Copy the sigframe out to the user's stack. */ 531 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 532 uprintf("pid %d comm %s has trashed its stack, killing\n", 533 p->p_pid, p->p_comm); 534 PROC_LOCK(p); 535 sigexit(td, SIGILL); 536 } 537 538 fpstate_drop(td); 539 /* Build the argument list for the signal handler. */ 540 regs->tf_rdi = sig; /* arg 1 in %rdi */ 541 regs->tf_rax = 0; 542 if (issiginfo) { 543 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 544 regs->tf_rdx = (register_t)&sfp->sf_uc; /* arg 3 in %rdx */ 545 } else { 546 regs->tf_rsi = 0; 547 regs->tf_rdx = 0; 548 } 549 regs->tf_rcx = (register_t)catcher; 550 regs->tf_rsp = (long)sfp; 551 regs->tf_rip = linux_rt_sigcode; 552 regs->tf_rflags &= ~(PSL_T | PSL_D); 553 regs->tf_cs = _ucodesel; 554 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 555 PROC_LOCK(p); 556 mtx_lock(&psp->ps_mtx); 557 } 558 559 #define LINUX_VSYSCALL_START (-10UL << 20) 560 #define LINUX_VSYSCALL_SZ 1024 561 562 const unsigned long linux_vsyscall_vector[] = { 563 LINUX_SYS_gettimeofday, 564 LINUX_SYS_linux_time, 565 LINUX_SYS_linux_getcpu, 566 }; 567 568 static int 569 linux_vsyscall(struct thread *td) 570 { 571 struct trapframe *frame; 572 uint64_t retqaddr; 573 int code, traced; 574 int error; 575 576 frame = td->td_frame; 577 578 /* Check %rip for vsyscall area. */ 579 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 580 return (EINVAL); 581 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 582 return (EINVAL); 583 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 584 if (code >= nitems(linux_vsyscall_vector)) 585 return (EINVAL); 586 587 /* 588 * vsyscall called as callq *(%rax), so we must 589 * use return address from %rsp and also fixup %rsp. 590 */ 591 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 592 if (error) 593 return (error); 594 595 frame->tf_rip = retqaddr; 596 frame->tf_rax = linux_vsyscall_vector[code]; 597 frame->tf_rsp += 8; 598 599 traced = (frame->tf_flags & PSL_T); 600 601 amd64_syscall(td, traced); 602 603 return (0); 604 } 605 606 struct sysentvec elf_linux_sysvec = { 607 .sv_size = LINUX_SYS_MAXSYSCALL, 608 .sv_table = linux_sysent, 609 .sv_fixup = __elfN(freebsd_fixup), 610 .sv_sendsig = linux_rt_sendsig, 611 .sv_sigcode = &_binary_linux_vdso_so_o_start, 612 .sv_szsigcode = &linux_szsigcode, 613 .sv_name = "Linux ELF64", 614 .sv_coredump = elf64_coredump, 615 .sv_elf_core_osabi = ELFOSABI_NONE, 616 .sv_elf_core_abi_vendor = LINUX_ABI_VENDOR, 617 .sv_elf_core_prepare_notes = linux64_prepare_notes, 618 .sv_imgact_try = linux_exec_imgact_try, 619 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 620 .sv_minuser = VM_MIN_ADDRESS, 621 .sv_maxuser = VM_MAXUSER_ADDRESS_LA48, 622 .sv_usrstack = LINUX_USRSTACK_LA48, 623 .sv_psstrings = LINUX_PS_STRINGS_LA48, 624 .sv_psstringssz = sizeof(struct ps_strings), 625 .sv_stackprot = VM_PROT_ALL, 626 .sv_copyout_auxargs = linux_copyout_auxargs, 627 .sv_copyout_strings = __linuxN(copyout_strings), 628 .sv_setregs = linux_exec_setregs, 629 .sv_fixlimit = NULL, 630 .sv_maxssiz = NULL, 631 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN | 632 SV_SIG_WAITNDQ | SV_TIMEKEEP, 633 .sv_set_syscall_retval = linux_set_syscall_retval, 634 .sv_fetch_syscall_args = linux_fetch_syscall_args, 635 .sv_syscallnames = linux_syscallnames, 636 .sv_shared_page_base = LINUX_SHAREDPAGE_LA48, 637 .sv_shared_page_len = PAGE_SIZE, 638 .sv_schedtail = linux_schedtail, 639 .sv_thread_detach = linux_thread_detach, 640 .sv_trap = linux_vsyscall, 641 .sv_onexec = linux_on_exec_vmspace, 642 .sv_onexit = linux_on_exit, 643 .sv_ontdexit = linux_thread_dtor, 644 .sv_setid_allowed = &linux_setid_allowed_query, 645 .sv_set_fork_retval = linux_set_fork_retval, 646 }; 647 648 static int 649 linux_on_exec_vmspace(struct proc *p, struct image_params *imgp) 650 { 651 int error; 652 653 error = linux_map_vdso(p, linux_vdso_obj, linux_vdso_base, 654 LINUX_VDSOPAGE_SIZE, imgp); 655 if (error == 0) 656 linux_on_exec(p, imgp); 657 return (error); 658 } 659 660 /* 661 * linux_vdso_install() and linux_exec_sysvec_init() must be called 662 * after exec_sysvec_init() which is SI_SUB_EXEC (SI_ORDER_ANY). 663 */ 664 static void 665 linux_exec_sysvec_init(void *param) 666 { 667 l_uintptr_t *ktimekeep_base, *ktsc_selector; 668 struct sysentvec *sv; 669 ptrdiff_t tkoff; 670 671 sv = param; 672 amd64_lower_shared_page(sv); 673 /* Fill timekeep_base */ 674 exec_sysvec_init(sv); 675 676 tkoff = kern_timekeep_base - linux_vdso_base; 677 ktimekeep_base = (l_uintptr_t *)(linux_vdso_mapping + tkoff); 678 *ktimekeep_base = sv->sv_shared_page_base + sv->sv_timekeep_offset; 679 680 tkoff = kern_tsc_selector - linux_vdso_base; 681 ktsc_selector = (l_uintptr_t *)(linux_vdso_mapping + tkoff); 682 *ktsc_selector = linux_vdso_tsc_selector_idx(); 683 if (bootverbose) 684 printf("Linux x86-64 vDSO tsc_selector: %lu\n", *ktsc_selector); 685 686 tkoff = kern_cpu_selector - linux_vdso_base; 687 ktsc_selector = (l_uintptr_t *)(linux_vdso_mapping + tkoff); 688 *ktsc_selector = linux_vdso_cpu_selector_idx(); 689 if (bootverbose) 690 printf("Linux x86-64 vDSO cpu_selector: %lu\n", *ktsc_selector); 691 } 692 SYSINIT(elf_linux_exec_sysvec_init, SI_SUB_EXEC + 1, SI_ORDER_ANY, 693 linux_exec_sysvec_init, &elf_linux_sysvec); 694 695 static void 696 linux_vdso_install(const void *param) 697 { 698 char *vdso_start = &_binary_linux_vdso_so_o_start; 699 char *vdso_end = &_binary_linux_vdso_so_o_end; 700 701 linux_szsigcode = vdso_end - vdso_start; 702 MPASS(linux_szsigcode <= LINUX_VDSOPAGE_SIZE); 703 704 linux_vdso_base = LINUX_VDSOPAGE_LA48; 705 if (hw_lower_amd64_sharedpage != 0) 706 linux_vdso_base -= PAGE_SIZE; 707 708 __elfN(linux_vdso_fixup)(vdso_start, linux_vdso_base); 709 710 linux_vdso_obj = __elfN(linux_shared_page_init) 711 (&linux_vdso_mapping, LINUX_VDSOPAGE_SIZE); 712 bcopy(vdso_start, linux_vdso_mapping, linux_szsigcode); 713 714 linux_vdso_reloc(linux_vdso_mapping, linux_vdso_base); 715 } 716 SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC + 1, SI_ORDER_FIRST, 717 linux_vdso_install, NULL); 718 719 static void 720 linux_vdso_deinstall(const void *param) 721 { 722 723 __elfN(linux_shared_page_fini)(linux_vdso_obj, 724 linux_vdso_mapping, LINUX_VDSOPAGE_SIZE); 725 } 726 SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 727 linux_vdso_deinstall, NULL); 728 729 static void 730 linux_vdso_reloc(char *mapping, Elf_Addr offset) 731 { 732 const Elf_Ehdr *ehdr; 733 const Elf_Shdr *shdr; 734 Elf64_Addr *where, val; 735 Elf_Size rtype, symidx; 736 const Elf_Rela *rela; 737 Elf_Addr addr, addend; 738 int relacnt; 739 int i, j; 740 741 MPASS(offset != 0); 742 743 relacnt = 0; 744 ehdr = (const Elf_Ehdr *)mapping; 745 shdr = (const Elf_Shdr *)(mapping + ehdr->e_shoff); 746 for (i = 0; i < ehdr->e_shnum; i++) 747 { 748 switch (shdr[i].sh_type) { 749 case SHT_REL: 750 printf("Linux x86_64 vDSO: unexpected Rel section\n"); 751 break; 752 case SHT_RELA: 753 rela = (const Elf_Rela *)(mapping + shdr[i].sh_offset); 754 relacnt = shdr[i].sh_size / sizeof(*rela); 755 } 756 } 757 758 for (j = 0; j < relacnt; j++, rela++) { 759 where = (Elf_Addr *)(mapping + rela->r_offset); 760 addend = rela->r_addend; 761 rtype = ELF_R_TYPE(rela->r_info); 762 symidx = ELF_R_SYM(rela->r_info); 763 764 switch (rtype) { 765 case R_X86_64_NONE: /* none */ 766 break; 767 768 case R_X86_64_RELATIVE: /* B + A */ 769 addr = (Elf_Addr)(offset + addend); 770 val = addr; 771 if (*where != val) 772 *where = val; 773 break; 774 case R_X86_64_IRELATIVE: 775 printf("Linux x86_64 vDSO: unexpected ifunc relocation, " 776 "symbol index %ld\n", symidx); 777 break; 778 default: 779 printf("Linux x86_64 vDSO: unexpected relocation type %ld, " 780 "symbol index %ld\n", rtype, symidx); 781 } 782 } 783 } 784 785 static Elf_Brandnote linux64_brandnote = { 786 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 787 .hdr.n_descsz = 16, 788 .hdr.n_type = 1, 789 .vendor = GNU_ABI_VENDOR, 790 .flags = BN_TRANSLATE_OSREL, 791 .trans_osrel = linux_trans_osrel 792 }; 793 794 static Elf64_Brandinfo linux_glibc2brand = { 795 .brand = ELFOSABI_LINUX, 796 .machine = EM_X86_64, 797 .compat_3_brand = "Linux", 798 .emul_path = linux_emul_path, 799 .interp_path = "/lib64/ld-linux-x86-64.so.2", 800 .sysvec = &elf_linux_sysvec, 801 .interp_newpath = NULL, 802 .brand_note = &linux64_brandnote, 803 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 804 }; 805 806 static Elf64_Brandinfo linux_glibc2brandshort = { 807 .brand = ELFOSABI_LINUX, 808 .machine = EM_X86_64, 809 .compat_3_brand = "Linux", 810 .emul_path = linux_emul_path, 811 .interp_path = "/lib64/ld-linux.so.2", 812 .sysvec = &elf_linux_sysvec, 813 .interp_newpath = NULL, 814 .brand_note = &linux64_brandnote, 815 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 816 }; 817 818 static Elf64_Brandinfo linux_muslbrand = { 819 .brand = ELFOSABI_LINUX, 820 .machine = EM_X86_64, 821 .compat_3_brand = "Linux", 822 .emul_path = linux_emul_path, 823 .interp_path = "/lib/ld-musl-x86_64.so.1", 824 .sysvec = &elf_linux_sysvec, 825 .interp_newpath = NULL, 826 .brand_note = &linux64_brandnote, 827 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE | 828 LINUX_BI_FUTEX_REQUEUE 829 }; 830 831 Elf64_Brandinfo *linux_brandlist[] = { 832 &linux_glibc2brand, 833 &linux_glibc2brandshort, 834 &linux_muslbrand, 835 NULL 836 }; 837 838 static int 839 linux64_elf_modevent(module_t mod, int type, void *data) 840 { 841 Elf64_Brandinfo **brandinfo; 842 int error; 843 struct linux_ioctl_handler **lihp; 844 845 error = 0; 846 847 switch(type) { 848 case MOD_LOAD: 849 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 850 ++brandinfo) 851 if (elf64_insert_brand_entry(*brandinfo) < 0) 852 error = EINVAL; 853 if (error == 0) { 854 SET_FOREACH(lihp, linux_ioctl_handler_set) 855 linux_ioctl_register_handler(*lihp); 856 stclohz = (stathz ? stathz : hz); 857 if (bootverbose) 858 printf("Linux x86-64 ELF exec handler installed\n"); 859 } else 860 printf("cannot insert Linux x86-64 ELF brand handler\n"); 861 break; 862 case MOD_UNLOAD: 863 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 864 ++brandinfo) 865 if (elf64_brand_inuse(*brandinfo)) 866 error = EBUSY; 867 if (error == 0) { 868 for (brandinfo = &linux_brandlist[0]; 869 *brandinfo != NULL; ++brandinfo) 870 if (elf64_remove_brand_entry(*brandinfo) < 0) 871 error = EINVAL; 872 } 873 if (error == 0) { 874 SET_FOREACH(lihp, linux_ioctl_handler_set) 875 linux_ioctl_unregister_handler(*lihp); 876 if (bootverbose) 877 printf("Linux x86_64 ELF exec handler removed\n"); 878 } else 879 printf("Could not deinstall Linux x86_64 ELF interpreter entry\n"); 880 break; 881 default: 882 return (EOPNOTSUPP); 883 } 884 return (error); 885 } 886 887 static moduledata_t linux64_elf_mod = { 888 "linux64elf", 889 linux64_elf_modevent, 890 0 891 }; 892 893 DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 894 MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 895 FEATURE(linux64, "Linux 64bit support"); 896