linux_sysvec.c revision 294136
1/*- 2 * Copyright (c) 2013 Dmitry Chagin 3 * Copyright (c) 2004 Tim J. Robbins 4 * Copyright (c) 2003 Peter Wemm 5 * Copyright (c) 2002 Doug Rabson 6 * Copyright (c) 1998-1999 Andrew Gallatin 7 * Copyright (c) 1994-1996 S��ren Schmidt 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer 15 * in this position and unchanged. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34#include <sys/cdefs.h> 35__FBSDID("$FreeBSD: stable/10/sys/amd64/linux/linux_sysvec.c 294136 2016-01-16 07:56:49Z dchagin $"); 36 37#include "opt_compat.h" 38 39#define __ELF_WORD_SIZE 64 40 41#include <sys/param.h> 42#include <sys/systm.h> 43#include <sys/exec.h> 44#include <sys/fcntl.h> 45#include <sys/imgact.h> 46#include <sys/imgact_elf.h> 47#include <sys/kernel.h> 48#include <sys/ktr.h> 49#include <sys/lock.h> 50#include <sys/malloc.h> 51#include <sys/module.h> 52#include <sys/mutex.h> 53#include <sys/proc.h> 54#include <sys/resourcevar.h> 55#include <sys/signalvar.h> 56#include <sys/sysctl.h> 57#include <sys/syscallsubr.h> 58#include <sys/sysent.h> 59#include <sys/sysproto.h> 60#include <sys/vnode.h> 61#include <sys/eventhandler.h> 62 63#include <vm/vm.h> 64#include <vm/pmap.h> 65#include <vm/vm_extern.h> 66#include <vm/vm_map.h> 67#include <vm/vm_object.h> 68#include <vm/vm_page.h> 69#include <vm/vm_param.h> 70 71#include <machine/cpu.h> 72#include <machine/md_var.h> 73#include <machine/pcb.h> 74#include <machine/specialreg.h> 75 76#include <amd64/linux/linux.h> 77#include <amd64/linux/linux_proto.h> 78#include <compat/linux/linux_emul.h> 79#include <compat/linux/linux_futex.h> 80#include <compat/linux/linux_ioctl.h> 81#include <compat/linux/linux_mib.h> 82#include <compat/linux/linux_misc.h> 83#include <compat/linux/linux_signal.h> 84#include <compat/linux/linux_sysproto.h> 85#include <compat/linux/linux_util.h> 86#include <compat/linux/linux_vdso.h> 87 88MODULE_VERSION(linux64, 1); 89 90#if BYTE_ORDER == LITTLE_ENDIAN 91#define SHELLMAGIC 0x2123 /* #! */ 92#else 93#define SHELLMAGIC 0x2321 94#endif 95 96#if defined(DEBUG) 97SYSCTL_PROC(_compat_linux, OID_AUTO, debug, 98 CTLTYPE_STRING | CTLFLAG_RW, 99 0, 0, linux_sysctl_debug, "A", 100 "Linux 64 debugging control"); 101#endif 102 103/* 104 * Allow the this functions to use the ldebug() facility 105 * even though they are not syscalls themselves. Map them 106 * to syscall 0. This is slightly less bogus than using 107 * ldebug(sigreturn). 108 */ 109#define LINUX_SYS_linux_rt_sendsig 0 110 111const char *linux_kplatform; 112static int linux_szsigcode; 113static vm_object_t linux_shared_page_obj; 114static char *linux_shared_page_mapping; 115extern char _binary_linux_locore_o_start; 116extern char _binary_linux_locore_o_end; 117 118extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; 119 120SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); 121 122static register_t * linux_copyout_strings(struct image_params *imgp); 123static int elf_linux_fixup(register_t **stack_base, 124 struct image_params *iparams); 125static boolean_t linux_trans_osrel(const Elf_Note *note, int32_t *osrel); 126static void linux_vdso_install(void *param); 127static void linux_vdso_deinstall(void *param); 128static void linux_set_syscall_retval(struct thread *td, int error); 129static int linux_fetch_syscall_args(struct thread *td, struct syscall_args *sa); 130static void linux_exec_setregs(struct thread *td, struct image_params *imgp, 131 u_long stack); 132static int linux_vsyscall(struct thread *td); 133 134/* 135 * Linux syscalls return negative errno's, we do positive and map them 136 * Reference: 137 * FreeBSD: src/sys/sys/errno.h 138 * Linux: linux-2.6.17.8/include/asm-generic/errno-base.h 139 * linux-2.6.17.8/include/asm-generic/errno.h 140 */ 141static int bsd_to_linux_errno[ELAST + 1] = { 142 -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, 143 -10, -35, -12, -13, -14, -15, -16, -17, -18, -19, 144 -20, -21, -22, -23, -24, -25, -26, -27, -28, -29, 145 -30, -31, -32, -33, -34, -11,-115,-114, -88, -89, 146 -90, -91, -92, -93, -94, -95, -96, -97, -98, -99, 147 -100,-101,-102,-103,-104,-105,-106,-107,-108,-109, 148 -110,-111, -40, -36,-112,-113, -39, -11, -87,-122, 149 -116, -66, -6, -6, -6, -6, -6, -37, -38, -9, 150 -6, -6, -43, -42, -75,-125, -84, -95, -16, -74, 151 -72, -67, -71 152}; 153 154#define LINUX_T_UNKNOWN 255 155static int _bsd_to_linux_trapcode[] = { 156 LINUX_T_UNKNOWN, /* 0 */ 157 6, /* 1 T_PRIVINFLT */ 158 LINUX_T_UNKNOWN, /* 2 */ 159 3, /* 3 T_BPTFLT */ 160 LINUX_T_UNKNOWN, /* 4 */ 161 LINUX_T_UNKNOWN, /* 5 */ 162 16, /* 6 T_ARITHTRAP */ 163 254, /* 7 T_ASTFLT */ 164 LINUX_T_UNKNOWN, /* 8 */ 165 13, /* 9 T_PROTFLT */ 166 1, /* 10 T_TRCTRAP */ 167 LINUX_T_UNKNOWN, /* 11 */ 168 14, /* 12 T_PAGEFLT */ 169 LINUX_T_UNKNOWN, /* 13 */ 170 17, /* 14 T_ALIGNFLT */ 171 LINUX_T_UNKNOWN, /* 15 */ 172 LINUX_T_UNKNOWN, /* 16 */ 173 LINUX_T_UNKNOWN, /* 17 */ 174 0, /* 18 T_DIVIDE */ 175 2, /* 19 T_NMI */ 176 4, /* 20 T_OFLOW */ 177 5, /* 21 T_BOUND */ 178 7, /* 22 T_DNA */ 179 8, /* 23 T_DOUBLEFLT */ 180 9, /* 24 T_FPOPFLT */ 181 10, /* 25 T_TSSFLT */ 182 11, /* 26 T_SEGNPFLT */ 183 12, /* 27 T_STKFLT */ 184 18, /* 28 T_MCHK */ 185 19, /* 29 T_XMMFLT */ 186 15 /* 30 T_RESERVED */ 187}; 188#define bsd_to_linux_trapcode(code) \ 189 ((code)<sizeof(_bsd_to_linux_trapcode)/sizeof(*_bsd_to_linux_trapcode)? \ 190 _bsd_to_linux_trapcode[(code)]: \ 191 LINUX_T_UNKNOWN) 192 193LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); 194LINUX_VDSO_SYM_CHAR(linux_platform); 195 196/* 197 * If FreeBSD & Linux have a difference of opinion about what a trap 198 * means, deal with it here. 199 * 200 * MPSAFE 201 */ 202static int 203translate_traps(int signal, int trap_code) 204{ 205 206 if (signal != SIGBUS) 207 return signal; 208 switch (trap_code) { 209 case T_PROTFLT: 210 case T_TSSFLT: 211 case T_DOUBLEFLT: 212 case T_PAGEFLT: 213 return SIGSEGV; 214 default: 215 return signal; 216 } 217} 218 219static int 220linux_fetch_syscall_args(struct thread *td, struct syscall_args *sa) 221{ 222 struct proc *p; 223 struct trapframe *frame; 224 225 p = td->td_proc; 226 frame = td->td_frame; 227 228 sa->args[0] = frame->tf_rdi; 229 sa->args[1] = frame->tf_rsi; 230 sa->args[2] = frame->tf_rdx; 231 sa->args[3] = frame->tf_rcx; 232 sa->args[4] = frame->tf_r8; 233 sa->args[5] = frame->tf_r9; 234 sa->code = frame->tf_rax; 235 236 if (sa->code >= p->p_sysent->sv_size) 237 /* nosys */ 238 sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1]; 239 else 240 sa->callp = &p->p_sysent->sv_table[sa->code]; 241 sa->narg = sa->callp->sy_narg; 242 243 td->td_retval[0] = 0; 244 return (0); 245} 246 247static void 248linux_set_syscall_retval(struct thread *td, int error) 249{ 250 struct trapframe *frame = td->td_frame; 251 252 /* 253 * On Linux only %rcx and %r11 values are not preserved across 254 * the syscall. 255 * So, do not clobber %rdx and %r10 256 */ 257 td->td_retval[1] = frame->tf_rdx; 258 frame->tf_r10 = frame->tf_rcx; 259 260 cpu_set_syscall_retval(td, error); 261 262 /* Restore all registers. */ 263 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 264} 265 266static int 267elf_linux_fixup(register_t **stack_base, struct image_params *imgp) 268{ 269 Elf_Auxargs *args; 270 Elf_Addr *base; 271 Elf_Addr *pos; 272 struct ps_strings *arginfo; 273 struct proc *p; 274 275 p = imgp->proc; 276 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 277 278 KASSERT(curthread->td_proc == imgp->proc, 279 ("unsafe elf_linux_fixup(), should be curproc")); 280 base = (Elf64_Addr *)*stack_base; 281 args = (Elf64_Auxargs *)imgp->auxargs; 282 pos = base + (imgp->args->argc + imgp->args->envc + 2); 283 284 AUXARGS_ENTRY(pos, LINUX_AT_SYSINFO_EHDR, 285 imgp->proc->p_sysent->sv_shared_page_base); 286 AUXARGS_ENTRY(pos, LINUX_AT_HWCAP, cpu_feature); 287 AUXARGS_ENTRY(pos, LINUX_AT_CLKTCK, stclohz); 288 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 289 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 290 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 291 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 292 AUXARGS_ENTRY(pos, AT_BASE, args->base); 293 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 294 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 295 AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); 296 AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); 297 AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); 298 AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); 299 AUXARGS_ENTRY(pos, LINUX_AT_SECURE, 0); 300 AUXARGS_ENTRY(pos, LINUX_AT_PLATFORM, PTROUT(linux_platform)); 301 AUXARGS_ENTRY(pos, LINUX_AT_RANDOM, imgp->canary); 302 if (imgp->execpathp != 0) 303 AUXARGS_ENTRY(pos, LINUX_AT_EXECFN, imgp->execpathp); 304 if (args->execfd != -1) 305 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 306 AUXARGS_ENTRY(pos, AT_NULL, 0); 307 free(imgp->auxargs, M_TEMP); 308 imgp->auxargs = NULL; 309 310 base--; 311 suword(base, (uint64_t)imgp->args->argc); 312 313 *stack_base = (register_t *)base; 314 return (0); 315} 316 317/* 318 * Copy strings out to the new process address space, constructing new arg 319 * and env vector tables. Return a pointer to the base so that it can be used 320 * as the initial stack pointer. 321 */ 322static register_t * 323linux_copyout_strings(struct image_params *imgp) 324{ 325 int argc, envc; 326 char **vectp; 327 char *stringp, *destp; 328 register_t *stack_base; 329 struct ps_strings *arginfo; 330 char canary[LINUX_AT_RANDOM_LEN]; 331 size_t execpath_len; 332 struct proc *p; 333 334 /* 335 * Calculate string base and vector table pointers. 336 */ 337 if (imgp->execpath != NULL && imgp->auxargs != NULL) 338 execpath_len = strlen(imgp->execpath) + 1; 339 else 340 execpath_len = 0; 341 342 p = imgp->proc; 343 arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; 344 destp = (caddr_t)arginfo - SPARE_USRSPACE - 345 roundup(sizeof(canary), sizeof(char *)) - 346 roundup(execpath_len, sizeof(char *)) - 347 roundup((ARG_MAX - imgp->args->stringspace), sizeof(char *)); 348 349 if (execpath_len != 0) { 350 imgp->execpathp = (uintptr_t)arginfo - execpath_len; 351 copyout(imgp->execpath, (void *)imgp->execpathp, execpath_len); 352 } 353 354 /* 355 * Prepare the canary for SSP. 356 */ 357 arc4rand(canary, sizeof(canary), 0); 358 imgp->canary = (uintptr_t)arginfo - 359 roundup(execpath_len, sizeof(char *)) - 360 roundup(sizeof(canary), sizeof(char *)); 361 copyout(canary, (void *)imgp->canary, sizeof(canary)); 362 363 /* 364 * If we have a valid auxargs ptr, prepare some room 365 * on the stack. 366 */ 367 if (imgp->auxargs) { 368 /* 369 * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for 370 * lower compatibility. 371 */ 372 imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : 373 (LINUX_AT_COUNT * 2); 374 375 /* 376 * The '+ 2' is for the null pointers at the end of each of 377 * the arg and env vector sets,and imgp->auxarg_size is room 378 * for argument of Runtime loader. 379 */ 380 vectp = (char **)(destp - (imgp->args->argc + 381 imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); 382 383 } else { 384 /* 385 * The '+ 2' is for the null pointers at the end of each of 386 * the arg and env vector sets 387 */ 388 vectp = (char **)(destp - (imgp->args->argc + 389 imgp->args->envc + 2) * sizeof(char *)); 390 } 391 392 /* 393 * vectp also becomes our initial stack base 394 */ 395 stack_base = (register_t *)vectp; 396 397 stringp = imgp->args->begin_argv; 398 argc = imgp->args->argc; 399 envc = imgp->args->envc; 400 401 /* 402 * Copy out strings - arguments and environment. 403 */ 404 copyout(stringp, destp, ARG_MAX - imgp->args->stringspace); 405 406 /* 407 * Fill in "ps_strings" struct for ps, w, etc. 408 */ 409 suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); 410 suword(&arginfo->ps_nargvstr, argc); 411 412 /* 413 * Fill in argument portion of vector table. 414 */ 415 for (; argc > 0; --argc) { 416 suword(vectp++, (long)(intptr_t)destp); 417 while (*stringp++ != 0) 418 destp++; 419 destp++; 420 } 421 422 /* a null vector table pointer separates the argp's from the envp's */ 423 suword(vectp++, 0); 424 425 suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); 426 suword(&arginfo->ps_nenvstr, envc); 427 428 /* 429 * Fill in environment portion of vector table. 430 */ 431 for (; envc > 0; --envc) { 432 suword(vectp++, (long)(intptr_t)destp); 433 while (*stringp++ != 0) 434 destp++; 435 destp++; 436 } 437 438 /* end of vector table is a null pointer */ 439 suword(vectp, 0); 440 return (stack_base); 441} 442 443/* 444 * Reset registers to default values on exec. 445 */ 446static void 447linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 448{ 449 struct trapframe *regs = td->td_frame; 450 struct pcb *pcb = td->td_pcb; 451 452 mtx_lock(&dt_lock); 453 if (td->td_proc->p_md.md_ldt != NULL) 454 user_ldt_free(td); 455 else 456 mtx_unlock(&dt_lock); 457 458 pcb->pcb_fsbase = 0; 459 pcb->pcb_gsbase = 0; 460 clear_pcb_flags(pcb, PCB_32BIT); 461 pcb->pcb_initial_fpucw = __LINUX_NPXCW__; 462 set_pcb_flags(pcb, PCB_FULL_IRET); 463 464 bzero((char *)regs, sizeof(struct trapframe)); 465 regs->tf_rip = imgp->entry_addr; 466 regs->tf_rsp = stack; 467 regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); 468 regs->tf_ss = _udatasel; 469 regs->tf_cs = _ucodesel; 470 regs->tf_ds = _udatasel; 471 regs->tf_es = _udatasel; 472 regs->tf_fs = _ufssel; 473 regs->tf_gs = _ugssel; 474 regs->tf_flags = TF_HASSEGS; 475 476 /* 477 * Reset the hardware debug registers if they were in use. 478 * They won't have any meaning for the newly exec'd process. 479 */ 480 if (pcb->pcb_flags & PCB_DBREGS) { 481 pcb->pcb_dr0 = 0; 482 pcb->pcb_dr1 = 0; 483 pcb->pcb_dr2 = 0; 484 pcb->pcb_dr3 = 0; 485 pcb->pcb_dr6 = 0; 486 pcb->pcb_dr7 = 0; 487 if (pcb == curpcb) { 488 /* 489 * Clear the debug registers on the running 490 * CPU, otherwise they will end up affecting 491 * the next process we switch to. 492 */ 493 reset_dbregs(); 494 } 495 clear_pcb_flags(pcb, PCB_DBREGS); 496 } 497 498 /* 499 * Drop the FP state if we hold it, so that the process gets a 500 * clean FP state if it uses the FPU again. 501 */ 502 fpstate_drop(td); 503} 504 505/* 506 * Copied from amd64/amd64/machdep.c 507 * 508 * XXX fpu state need? don't think so 509 */ 510int 511linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) 512{ 513 struct proc *p; 514 struct l_ucontext uc; 515 struct l_sigcontext *context; 516 struct trapframe *regs; 517 unsigned long rflags; 518 int error; 519 ksiginfo_t ksi; 520 521 regs = td->td_frame; 522 error = copyin((void *)regs->tf_rbx, &uc, sizeof(uc)); 523 if (error != 0) 524 return (error); 525 526 p = td->td_proc; 527 context = &uc.uc_mcontext; 528 rflags = context->sc_rflags; 529 530 /* 531 * Don't allow users to change privileged or reserved flags. 532 */ 533 /* 534 * XXX do allow users to change the privileged flag PSL_RF. 535 * The cpu sets PSL_RF in tf_rflags for faults. Debuggers 536 * should sometimes set it there too. tf_rflags is kept in 537 * the signal context during signal handling and there is no 538 * other place to remember it, so the PSL_RF bit may be 539 * corrupted by the signal handler without us knowing. 540 * Corruption of the PSL_RF bit at worst causes one more or 541 * one less debugger trap, so allowing it is fairly harmless. 542 */ 543 544#define RFLAG_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) 545 if (!RFLAG_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { 546 printf("linux_rt_sigreturn: rflags = 0x%lx\n", rflags); 547 return (EINVAL); 548 } 549 550 /* 551 * Don't allow users to load a valid privileged %cs. Let the 552 * hardware check for invalid selectors, excess privilege in 553 * other selectors, invalid %eip's and invalid %esp's. 554 */ 555#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) 556 if (!CS_SECURE(context->sc_cs)) { 557 printf("linux_rt_sigreturn: cs = 0x%x\n", context->sc_cs); 558 ksiginfo_init_trap(&ksi); 559 ksi.ksi_signo = SIGBUS; 560 ksi.ksi_code = BUS_OBJERR; 561 ksi.ksi_trapno = T_PROTFLT; 562 ksi.ksi_addr = (void *)regs->tf_rip; 563 trapsignal(td, &ksi); 564 return (EINVAL); 565 } 566 567 PROC_LOCK(p); 568 linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); 569 SIG_CANTMASK(td->td_sigmask); 570 signotify(td); 571 PROC_UNLOCK(p); 572 573 regs->tf_rdi = context->sc_rdi; 574 regs->tf_rsi = context->sc_rsi; 575 regs->tf_rdx = context->sc_rdx; 576 regs->tf_rbp = context->sc_rbp; 577 regs->tf_rbx = context->sc_rbx; 578 regs->tf_rcx = context->sc_rcx; 579 regs->tf_rax = context->sc_rax; 580 regs->tf_rip = context->sc_rip; 581 regs->tf_rsp = context->sc_rsp; 582 regs->tf_r8 = context->sc_r8; 583 regs->tf_r9 = context->sc_r9; 584 regs->tf_r10 = context->sc_r10; 585 regs->tf_r11 = context->sc_r11; 586 regs->tf_r12 = context->sc_r12; 587 regs->tf_r13 = context->sc_r13; 588 regs->tf_r14 = context->sc_r14; 589 regs->tf_r15 = context->sc_r15; 590 regs->tf_cs = context->sc_cs; 591 regs->tf_err = context->sc_err; 592 regs->tf_rflags = rflags; 593 594 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 595 return (EJUSTRETURN); 596} 597 598/* 599 * copied from amd64/amd64/machdep.c 600 * 601 * Send an interrupt to process. 602 */ 603static void 604linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 605{ 606 struct l_rt_sigframe sf, *sfp; 607 struct proc *p; 608 struct thread *td; 609 struct sigacts *psp; 610 caddr_t sp; 611 struct trapframe *regs; 612 int sig, code; 613 int oonstack; 614 615 td = curthread; 616 p = td->td_proc; 617 PROC_LOCK_ASSERT(p, MA_OWNED); 618 sig = ksi->ksi_signo; 619 psp = p->p_sigacts; 620 code = ksi->ksi_code; 621 mtx_assert(&psp->ps_mtx, MA_OWNED); 622 regs = td->td_frame; 623 oonstack = sigonstack(regs->tf_rsp); 624 625 LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", 626 catcher, sig, mask, code); 627 628 /* Allocate space for the signal handler context. */ 629 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 630 SIGISMEMBER(psp->ps_sigonstack, sig)) { 631 sp = td->td_sigstk.ss_sp + td->td_sigstk.ss_size - 632 sizeof(struct l_rt_sigframe); 633 } else 634 sp = (caddr_t)regs->tf_rsp - sizeof(struct l_rt_sigframe) - 128; 635 /* Align to 16 bytes. */ 636 sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); 637 mtx_unlock(&psp->ps_mtx); 638 639 /* Translate the signal. */ 640 sig = bsd_to_linux_signal(sig); 641 642 /* Save user context. */ 643 bzero(&sf, sizeof(sf)); 644 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_sigmask); 645 bsd_to_linux_sigset(mask, &sf.sf_sc.uc_mcontext.sc_mask); 646 647 sf.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); 648 sf.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; 649 sf.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 650 ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; 651 PROC_UNLOCK(p); 652 653 sf.sf_sc.uc_mcontext.sc_rdi = regs->tf_rdi; 654 sf.sf_sc.uc_mcontext.sc_rsi = regs->tf_rsi; 655 sf.sf_sc.uc_mcontext.sc_rdx = regs->tf_rdx; 656 sf.sf_sc.uc_mcontext.sc_rbp = regs->tf_rbp; 657 sf.sf_sc.uc_mcontext.sc_rbx = regs->tf_rbx; 658 sf.sf_sc.uc_mcontext.sc_rcx = regs->tf_rcx; 659 sf.sf_sc.uc_mcontext.sc_rax = regs->tf_rax; 660 sf.sf_sc.uc_mcontext.sc_rip = regs->tf_rip; 661 sf.sf_sc.uc_mcontext.sc_rsp = regs->tf_rsp; 662 sf.sf_sc.uc_mcontext.sc_r8 = regs->tf_r8; 663 sf.sf_sc.uc_mcontext.sc_r9 = regs->tf_r9; 664 sf.sf_sc.uc_mcontext.sc_r10 = regs->tf_r10; 665 sf.sf_sc.uc_mcontext.sc_r11 = regs->tf_r11; 666 sf.sf_sc.uc_mcontext.sc_r12 = regs->tf_r12; 667 sf.sf_sc.uc_mcontext.sc_r13 = regs->tf_r13; 668 sf.sf_sc.uc_mcontext.sc_r14 = regs->tf_r14; 669 sf.sf_sc.uc_mcontext.sc_r15 = regs->tf_r15; 670 sf.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; 671 sf.sf_sc.uc_mcontext.sc_rflags = regs->tf_rflags; 672 sf.sf_sc.uc_mcontext.sc_err = regs->tf_err; 673 sf.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); 674 sf.sf_sc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; 675 676 /* Build the argument list for the signal handler. */ 677 regs->tf_rdi = sig; /* arg 1 in %rdi */ 678 regs->tf_rax = 0; 679 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ 680 regs->tf_rdx = (register_t)&sfp->sf_sc; /* arg 3 in %rdx */ 681 682 sf.sf_handler = catcher; 683 /* Fill in POSIX parts */ 684 ksiginfo_to_lsiginfo(ksi, &sf.sf_si, sig); 685 686 /* 687 * Copy the sigframe out to the user's stack. 688 */ 689 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 690#ifdef DEBUG 691 printf("process %ld has trashed its stack\n", (long)p->p_pid); 692#endif 693 PROC_LOCK(p); 694 sigexit(td, SIGILL); 695 } 696 697 regs->tf_rsp = (long)sfp; 698 regs->tf_rip = linux_rt_sigcode; 699 regs->tf_rflags &= ~(PSL_T | PSL_D); 700 regs->tf_cs = _ucodesel; 701 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 702 PROC_LOCK(p); 703 mtx_lock(&psp->ps_mtx); 704} 705 706/* 707 * If a linux binary is exec'ing something, try this image activator 708 * first. We override standard shell script execution in order to 709 * be able to modify the interpreter path. We only do this if a linux 710 * binary is doing the exec, so we do not create an EXEC module for it. 711 */ 712static int exec_linux_imgact_try(struct image_params *iparams); 713 714static int 715exec_linux_imgact_try(struct image_params *imgp) 716{ 717 const char *head = (const char *)imgp->image_header; 718 char *rpath; 719 int error = -1, len; 720 721 /* 722 * The interpreter for shell scripts run from a linux binary needs 723 * to be located in /compat/linux if possible in order to recursively 724 * maintain linux path emulation. 725 */ 726 if (((const short *)head)[0] == SHELLMAGIC) { 727 /* 728 * Run our normal shell image activator. If it succeeds 729 * attempt to use the alternate path for the interpreter. 730 * If an alternate path is found, use our stringspace 731 * to store it. 732 */ 733 if ((error = exec_shell_imgact(imgp)) == 0) { 734 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc), 735 imgp->interpreter_name, UIO_SYSSPACE, 736 &rpath, 0, AT_FDCWD); 737 if (rpath != NULL) { 738 len = strlen(rpath) + 1; 739 740 if (len <= MAXSHELLCMDLEN) 741 memcpy(imgp->interpreter_name, 742 rpath, len); 743 free(rpath, M_TEMP); 744 } 745 } 746 } 747 return(error); 748} 749 750#define LINUX_VSYSCALL_START (-10UL << 20) 751#define LINUX_VSYSCALL_SZ 1024 752 753const unsigned long linux_vsyscall_vector[] = { 754 LINUX_SYS_gettimeofday, 755 LINUX_SYS_linux_time, 756 /* getcpu not implemented */ 757}; 758 759static int 760linux_vsyscall(struct thread *td) 761{ 762 struct trapframe *frame; 763 uint64_t retqaddr; 764 int code, traced; 765 int error; 766 767 frame = td->td_frame; 768 769 /* Check %rip for vsyscall area */ 770 if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) 771 return (EINVAL); 772 if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) 773 return (EINVAL); 774 code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; 775 if (code >= nitems(linux_vsyscall_vector)) 776 return (EINVAL); 777 778 /* 779 * vsyscall called as callq *(%rax), so we must 780 * use return address from %rsp and also fixup %rsp 781 */ 782 error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); 783 if (error) 784 return (error); 785 786 frame->tf_rip = retqaddr; 787 frame->tf_rax = linux_vsyscall_vector[code]; 788 frame->tf_rsp += 8; 789 790 traced = (frame->tf_flags & PSL_T); 791 792 amd64_syscall(td, traced); 793 794 return (0); 795} 796 797struct sysentvec elf_linux_sysvec = { 798 .sv_size = LINUX_SYS_MAXSYSCALL, 799 .sv_table = linux_sysent, 800 .sv_mask = 0, 801 .sv_sigsize = 0, 802 .sv_sigtbl = NULL, 803 .sv_errsize = ELAST + 1, 804 .sv_errtbl = bsd_to_linux_errno, 805 .sv_transtrap = translate_traps, 806 .sv_fixup = elf_linux_fixup, 807 .sv_sendsig = linux_rt_sendsig, 808 .sv_sigcode = &_binary_linux_locore_o_start, 809 .sv_szsigcode = &linux_szsigcode, 810 .sv_prepsyscall = NULL, 811 .sv_name = "Linux ELF64", 812 .sv_coredump = elf64_coredump, 813 .sv_imgact_try = exec_linux_imgact_try, 814 .sv_minsigstksz = LINUX_MINSIGSTKSZ, 815 .sv_pagesize = PAGE_SIZE, 816 .sv_minuser = VM_MIN_ADDRESS, 817 .sv_maxuser = VM_MAXUSER_ADDRESS, 818 .sv_usrstack = USRSTACK, 819 .sv_psstrings = PS_STRINGS, 820 .sv_stackprot = VM_PROT_ALL, 821 .sv_copyout_strings = linux_copyout_strings, 822 .sv_setregs = linux_exec_setregs, 823 .sv_fixlimit = NULL, 824 .sv_maxssiz = NULL, 825 .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP, 826 .sv_set_syscall_retval = linux_set_syscall_retval, 827 .sv_fetch_syscall_args = linux_fetch_syscall_args, 828 .sv_syscallnames = NULL, 829 .sv_shared_page_base = SHAREDPAGE, 830 .sv_shared_page_len = PAGE_SIZE, 831 .sv_schedtail = linux_schedtail, 832 .sv_thread_detach = linux_thread_detach, 833 .sv_trap = linux_vsyscall, 834}; 835 836static void 837linux_vdso_install(void *param) 838{ 839 840 linux_szsigcode = (&_binary_linux_locore_o_end - 841 &_binary_linux_locore_o_start); 842 843 if (linux_szsigcode > elf_linux_sysvec.sv_shared_page_len) 844 panic("Linux invalid vdso size\n"); 845 846 __elfN(linux_vdso_fixup)(&elf_linux_sysvec); 847 848 linux_shared_page_obj = __elfN(linux_shared_page_init) 849 (&linux_shared_page_mapping); 850 851 __elfN(linux_vdso_reloc)(&elf_linux_sysvec, SHAREDPAGE); 852 853 bcopy(elf_linux_sysvec.sv_sigcode, linux_shared_page_mapping, 854 linux_szsigcode); 855 elf_linux_sysvec.sv_shared_page_obj = linux_shared_page_obj; 856 857 linux_kplatform = linux_shared_page_mapping + 858 (linux_platform - (caddr_t)SHAREDPAGE); 859} 860SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC, SI_ORDER_ANY, 861 (sysinit_cfunc_t)linux_vdso_install, NULL); 862 863static void 864linux_vdso_deinstall(void *param) 865{ 866 867 __elfN(linux_shared_page_fini)(linux_shared_page_obj); 868}; 869SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, 870 (sysinit_cfunc_t)linux_vdso_deinstall, NULL); 871 872static char GNULINUX_ABI_VENDOR[] = "GNU"; 873static int GNULINUX_ABI_DESC = 0; 874 875static boolean_t 876linux_trans_osrel(const Elf_Note *note, int32_t *osrel) 877{ 878 const Elf32_Word *desc; 879 uintptr_t p; 880 881 p = (uintptr_t)(note + 1); 882 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 883 884 desc = (const Elf32_Word *)p; 885 if (desc[0] != GNULINUX_ABI_DESC) 886 return (FALSE); 887 888 /* 889 * For linux we encode osrel as follows (see linux_mib.c): 890 * VVVMMMIII (version, major, minor), see linux_mib.c. 891 */ 892 *osrel = desc[1] * 1000000 + desc[2] * 1000 + desc[3]; 893 894 return (TRUE); 895} 896 897static Elf_Brandnote linux64_brandnote = { 898 .hdr.n_namesz = sizeof(GNULINUX_ABI_VENDOR), 899 .hdr.n_descsz = 16, 900 .hdr.n_type = 1, 901 .vendor = GNULINUX_ABI_VENDOR, 902 .flags = BN_TRANSLATE_OSREL, 903 .trans_osrel = linux_trans_osrel 904}; 905 906static Elf64_Brandinfo linux_glibc2brand = { 907 .brand = ELFOSABI_LINUX, 908 .machine = EM_X86_64, 909 .compat_3_brand = "Linux", 910 .emul_path = "/compat/linux", 911 .interp_path = "/lib64/ld-linux-x86-64.so.2", 912 .sysvec = &elf_linux_sysvec, 913 .interp_newpath = NULL, 914 .brand_note = &linux64_brandnote, 915 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 916}; 917 918static Elf64_Brandinfo linux_glibc2brandshort = { 919 .brand = ELFOSABI_LINUX, 920 .machine = EM_X86_64, 921 .compat_3_brand = "Linux", 922 .emul_path = "/compat/linux", 923 .interp_path = "/lib64/ld-linux.so.2", 924 .sysvec = &elf_linux_sysvec, 925 .interp_newpath = NULL, 926 .brand_note = &linux64_brandnote, 927 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE 928}; 929 930Elf64_Brandinfo *linux_brandlist[] = { 931 &linux_glibc2brand, 932 &linux_glibc2brandshort, 933 NULL 934}; 935 936static int 937linux64_elf_modevent(module_t mod, int type, void *data) 938{ 939 Elf64_Brandinfo **brandinfo; 940 int error; 941 struct linux_ioctl_handler **lihp; 942 943 error = 0; 944 945 switch(type) { 946 case MOD_LOAD: 947 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 948 ++brandinfo) 949 if (elf64_insert_brand_entry(*brandinfo) < 0) 950 error = EINVAL; 951 if (error == 0) { 952 SET_FOREACH(lihp, linux_ioctl_handler_set) 953 linux_ioctl_register_handler(*lihp); 954 LIST_INIT(&futex_list); 955 mtx_init(&futex_mtx, "ftllk64", NULL, MTX_DEF); 956 stclohz = (stathz ? stathz : hz); 957 if (bootverbose) 958 printf("Linux x86-64 ELF exec handler installed\n"); 959 } else 960 printf("cannot insert Linux x86-64 ELF brand handler\n"); 961 break; 962 case MOD_UNLOAD: 963 for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; 964 ++brandinfo) 965 if (elf64_brand_inuse(*brandinfo)) 966 error = EBUSY; 967 if (error == 0) { 968 for (brandinfo = &linux_brandlist[0]; 969 *brandinfo != NULL; ++brandinfo) 970 if (elf64_remove_brand_entry(*brandinfo) < 0) 971 error = EINVAL; 972 } 973 if (error == 0) { 974 SET_FOREACH(lihp, linux_ioctl_handler_set) 975 linux_ioctl_unregister_handler(*lihp); 976 mtx_destroy(&futex_mtx); 977 if (bootverbose) 978 printf("Linux ELF exec handler removed\n"); 979 } else 980 printf("Could not deinstall ELF interpreter entry\n"); 981 break; 982 default: 983 return (EOPNOTSUPP); 984 } 985 return (error); 986} 987 988static moduledata_t linux64_elf_mod = { 989 "linux64elf", 990 linux64_elf_modevent, 991 0 992}; 993 994DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); 995MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); 996