1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2003 Peter Wemm 5 * Copyright (c) 1982, 1987, 1990 The Regents of the University of California. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * William Jolitz. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 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. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #include <sys/param.h> 38 #include <sys/exec.h> 39 #include <sys/fcntl.h> 40 #include <sys/imgact.h> 41 #include <sys/kernel.h> 42 #include <sys/lock.h> 43 #include <sys/malloc.h> 44 #include <sys/mutex.h> 45 #include <sys/mman.h> 46 #include <sys/namei.h> 47 #include <sys/proc.h> 48 #include <sys/procfs.h> 49 #include <sys/resourcevar.h> 50 #include <sys/systm.h> 51 #include <sys/signalvar.h> 52 #include <sys/stat.h> 53 #include <sys/sx.h> 54 #include <sys/syscall.h> 55 #include <sys/syscallsubr.h> 56 #include <sys/sysctl.h> 57 #include <sys/sysent.h> 58 #include <sys/vnode.h> 59 60 #include <vm/vm.h> 61 #include <vm/vm_kern.h> 62 #include <vm/vm_param.h> 63 #include <vm/pmap.h> 64 #include <vm/vm_map.h> 65 #include <vm/vm_object.h> 66 #include <vm/vm_extern.h> 67 68 #include <compat/freebsd32/freebsd32_signal.h> 69 #include <compat/freebsd32/freebsd32_util.h> 70 #include <compat/freebsd32/freebsd32_proto.h> 71 #include <compat/freebsd32/freebsd32.h> 72 #include <compat/ia32/ia32_signal.h> 73 #include <machine/psl.h> 74 #include <machine/segments.h> 75 #include <machine/specialreg.h> 76 #include <machine/frame.h> 77 #include <machine/md_var.h> 78 #include <machine/pcb.h> 79 #include <machine/cpufunc.h> 80 #include <machine/trap.h> 81 82 #include "vdso_ia32_offsets.h" 83 84 extern const char _binary_elf_vdso32_so_1_start[]; 85 extern const char _binary_elf_vdso32_so_1_end[]; 86 extern char _binary_elf_vdso32_so_1_size; 87 88 #ifdef COMPAT_FREEBSD4 89 static void freebsd4_ia32_sendsig(sig_t, ksiginfo_t *, sigset_t *); 90 #endif 91 92 static void 93 ia32_get_fpcontext(struct thread *td, struct ia32_mcontext *mcp, 94 char **xfpusave, size_t *xfpusave_len) 95 { 96 /* 97 * XXX Format of 64bit and 32bit FXSAVE areas differs. FXSAVE 98 * in 32bit mode saves %cs and %ds, while on 64bit it saves 99 * 64bit instruction and data pointers. Ignore the difference 100 * for now, it should be irrelevant for most applications. 101 */ 102 mcp->mc_ownedfp = fpugetregs(td); 103 bcopy(get_pcb_user_save_td(td), &mcp->mc_fpstate[0], 104 sizeof(mcp->mc_fpstate)); 105 mcp->mc_fpformat = fpuformat(); 106 if (xfpusave == NULL) 107 return; 108 if (!use_xsave || cpu_max_ext_state_size <= sizeof(struct savefpu)) { 109 *xfpusave_len = 0; 110 *xfpusave = NULL; 111 } else { 112 mcp->mc_flags |= _MC_IA32_HASFPXSTATE; 113 *xfpusave_len = mcp->mc_xfpustate_len = 114 cpu_max_ext_state_size - sizeof(struct savefpu); 115 *xfpusave = (char *)(get_pcb_user_save_td(td) + 1); 116 } 117 } 118 119 static int 120 ia32_set_fpcontext(struct thread *td, struct ia32_mcontext *mcp, 121 char *xfpustate, size_t xfpustate_len) 122 { 123 int error; 124 125 if (mcp->mc_fpformat == _MC_FPFMT_NODEV) 126 return (0); 127 else if (mcp->mc_fpformat != _MC_FPFMT_XMM) 128 return (EINVAL); 129 else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE) { 130 /* We don't care what state is left in the FPU or PCB. */ 131 fpstate_drop(td); 132 error = 0; 133 } else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU || 134 mcp->mc_ownedfp == _MC_FPOWNED_PCB) { 135 error = fpusetregs(td, (struct savefpu *)&mcp->mc_fpstate, 136 xfpustate, xfpustate_len); 137 } else 138 return (EINVAL); 139 return (error); 140 } 141 142 /* 143 * Get machine context. 144 */ 145 static int 146 ia32_get_mcontext(struct thread *td, struct ia32_mcontext *mcp, int flags) 147 { 148 struct pcb *pcb; 149 struct trapframe *tp; 150 151 pcb = td->td_pcb; 152 tp = td->td_frame; 153 154 PROC_LOCK(curthread->td_proc); 155 mcp->mc_onstack = sigonstack(tp->tf_rsp); 156 PROC_UNLOCK(curthread->td_proc); 157 /* Entry into kernel always sets TF_HASSEGS */ 158 mcp->mc_gs = tp->tf_gs; 159 mcp->mc_fs = tp->tf_fs; 160 mcp->mc_es = tp->tf_es; 161 mcp->mc_ds = tp->tf_ds; 162 mcp->mc_edi = tp->tf_rdi; 163 mcp->mc_esi = tp->tf_rsi; 164 mcp->mc_ebp = tp->tf_rbp; 165 mcp->mc_isp = tp->tf_rsp; 166 mcp->mc_eflags = tp->tf_rflags; 167 if (flags & GET_MC_CLEAR_RET) { 168 mcp->mc_eax = 0; 169 mcp->mc_edx = 0; 170 mcp->mc_eflags &= ~PSL_C; 171 } else { 172 mcp->mc_eax = tp->tf_rax; 173 mcp->mc_edx = tp->tf_rdx; 174 } 175 mcp->mc_ebx = tp->tf_rbx; 176 mcp->mc_ecx = tp->tf_rcx; 177 mcp->mc_eip = tp->tf_rip; 178 mcp->mc_cs = tp->tf_cs; 179 mcp->mc_esp = tp->tf_rsp; 180 mcp->mc_ss = tp->tf_ss; 181 mcp->mc_len = sizeof(*mcp); 182 mcp->mc_flags = tp->tf_flags; 183 ia32_get_fpcontext(td, mcp, NULL, 0); 184 mcp->mc_fsbase = pcb->pcb_fsbase; 185 mcp->mc_gsbase = pcb->pcb_gsbase; 186 mcp->mc_xfpustate = 0; 187 mcp->mc_xfpustate_len = 0; 188 bzero(mcp->mc_spare2, sizeof(mcp->mc_spare2)); 189 return (0); 190 } 191 192 /* 193 * Set machine context. 194 * 195 * However, we don't set any but the user modifiable flags, and we won't 196 * touch the cs selector. 197 */ 198 static int 199 ia32_set_mcontext(struct thread *td, struct ia32_mcontext *mcp) 200 { 201 struct trapframe *tp; 202 char *xfpustate; 203 long rflags; 204 int ret; 205 206 tp = td->td_frame; 207 if (mcp->mc_len != sizeof(*mcp)) 208 return (EINVAL); 209 rflags = (mcp->mc_eflags & PSL_USERCHANGE) | 210 (tp->tf_rflags & ~PSL_USERCHANGE); 211 if (mcp->mc_flags & _MC_IA32_HASFPXSTATE) { 212 if (mcp->mc_xfpustate_len > cpu_max_ext_state_size - 213 sizeof(struct savefpu)) 214 return (EINVAL); 215 xfpustate = (char *)fpu_save_area_alloc(); 216 ret = copyin(PTRIN(mcp->mc_xfpustate), xfpustate, 217 mcp->mc_xfpustate_len); 218 if (ret != 0) { 219 fpu_save_area_free((struct savefpu *)xfpustate); 220 return (ret); 221 } 222 } else 223 xfpustate = NULL; 224 ret = ia32_set_fpcontext(td, mcp, xfpustate, mcp->mc_xfpustate_len); 225 fpu_save_area_free((struct savefpu *)xfpustate); 226 if (ret != 0) 227 return (ret); 228 tp->tf_gs = mcp->mc_gs; 229 tp->tf_fs = mcp->mc_fs; 230 tp->tf_es = mcp->mc_es; 231 tp->tf_ds = mcp->mc_ds; 232 tp->tf_flags = TF_HASSEGS; 233 tp->tf_rdi = mcp->mc_edi; 234 tp->tf_rsi = mcp->mc_esi; 235 tp->tf_rbp = mcp->mc_ebp; 236 tp->tf_rbx = mcp->mc_ebx; 237 tp->tf_rdx = mcp->mc_edx; 238 tp->tf_rcx = mcp->mc_ecx; 239 tp->tf_rax = mcp->mc_eax; 240 /* trapno, err */ 241 tp->tf_rip = mcp->mc_eip; 242 tp->tf_rflags = rflags; 243 tp->tf_rsp = mcp->mc_esp; 244 tp->tf_ss = mcp->mc_ss; 245 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 246 return (0); 247 } 248 249 /* 250 * The first two fields of a ucontext_t are the signal mask and 251 * the machine context. The next field is uc_link; we want to 252 * avoid destroying the link when copying out contexts. 253 */ 254 #define UC_COPY_SIZE offsetof(struct ia32_ucontext, uc_link) 255 256 int 257 freebsd32_getcontext(struct thread *td, struct freebsd32_getcontext_args *uap) 258 { 259 struct ia32_ucontext uc; 260 int ret; 261 262 if (uap->ucp == NULL) 263 ret = EINVAL; 264 else { 265 bzero(&uc, sizeof(uc)); 266 ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET); 267 PROC_LOCK(td->td_proc); 268 uc.uc_sigmask = td->td_sigmask; 269 PROC_UNLOCK(td->td_proc); 270 ret = copyout(&uc, uap->ucp, UC_COPY_SIZE); 271 } 272 return (ret); 273 } 274 275 int 276 freebsd32_setcontext(struct thread *td, struct freebsd32_setcontext_args *uap) 277 { 278 struct ia32_ucontext uc; 279 int ret; 280 281 if (uap->ucp == NULL) 282 ret = EINVAL; 283 else { 284 ret = copyin(uap->ucp, &uc, UC_COPY_SIZE); 285 if (ret == 0) { 286 ret = ia32_set_mcontext(td, &uc.uc_mcontext); 287 if (ret == 0) { 288 kern_sigprocmask(td, SIG_SETMASK, 289 &uc.uc_sigmask, NULL, 0); 290 } 291 } 292 } 293 return (ret == 0 ? EJUSTRETURN : ret); 294 } 295 296 int 297 freebsd32_swapcontext(struct thread *td, struct freebsd32_swapcontext_args *uap) 298 { 299 struct ia32_ucontext uc; 300 int ret; 301 302 if (uap->oucp == NULL || uap->ucp == NULL) 303 ret = EINVAL; 304 else { 305 bzero(&uc, sizeof(uc)); 306 ia32_get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET); 307 PROC_LOCK(td->td_proc); 308 uc.uc_sigmask = td->td_sigmask; 309 PROC_UNLOCK(td->td_proc); 310 ret = copyout(&uc, uap->oucp, UC_COPY_SIZE); 311 if (ret == 0) { 312 ret = copyin(uap->ucp, &uc, UC_COPY_SIZE); 313 if (ret == 0) { 314 ret = ia32_set_mcontext(td, &uc.uc_mcontext); 315 if (ret == 0) { 316 kern_sigprocmask(td, SIG_SETMASK, 317 &uc.uc_sigmask, NULL, 0); 318 } 319 } 320 } 321 } 322 return (ret == 0 ? EJUSTRETURN : ret); 323 } 324 325 /* 326 * Send an interrupt to process. 327 * 328 * Stack is set up to allow sigcode stored 329 * at top to call routine, followed by kcall 330 * to sigreturn routine below. After sigreturn 331 * resets the signal mask, the stack, and the 332 * frame pointer, it returns to the user 333 * specified pc, psl. 334 */ 335 336 #ifdef COMPAT_43 337 static void 338 ia32_osendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 339 { 340 struct ia32_osigframe sf, *fp; 341 struct proc *p; 342 struct thread *td; 343 struct sigacts *psp; 344 struct trapframe *regs; 345 int sig; 346 int oonstack; 347 348 td = curthread; 349 p = td->td_proc; 350 PROC_LOCK_ASSERT(p, MA_OWNED); 351 sig = ksi->ksi_signo; 352 psp = p->p_sigacts; 353 mtx_assert(&psp->ps_mtx, MA_OWNED); 354 regs = td->td_frame; 355 oonstack = sigonstack(regs->tf_rsp); 356 357 /* Allocate space for the signal handler context. */ 358 if ((td->td_pflags & TDP_ALTSTACK) && !oonstack && 359 SIGISMEMBER(psp->ps_sigonstack, sig)) { 360 fp = (struct ia32_osigframe *)((uintptr_t)td->td_sigstk.ss_sp + 361 td->td_sigstk.ss_size - sizeof(sf)); 362 td->td_sigstk.ss_flags |= SS_ONSTACK; 363 } else 364 fp = (struct ia32_osigframe *)regs->tf_rsp - 1; 365 366 /* Build the argument list for the signal handler. */ 367 sf.sf_signum = sig; 368 sf.sf_scp = (register_t)&fp->sf_siginfo.si_sc; 369 bzero(&sf.sf_siginfo, sizeof(sf.sf_siginfo)); 370 if (SIGISMEMBER(psp->ps_siginfo, sig)) { 371 /* Signal handler installed with SA_SIGINFO. */ 372 sf.sf_arg2 = (register_t)&fp->sf_siginfo; 373 sf.sf_siginfo.si_signo = sig; 374 sf.sf_siginfo.si_code = ksi->ksi_code; 375 sf.sf_ah = (uintptr_t)catcher; 376 sf.sf_addr = 0; 377 } else { 378 /* Old FreeBSD-style arguments. */ 379 sf.sf_arg2 = ksi->ksi_code; 380 sf.sf_addr = (register_t)ksi->ksi_addr; 381 sf.sf_ah = (uintptr_t)catcher; 382 } 383 mtx_unlock(&psp->ps_mtx); 384 PROC_UNLOCK(p); 385 386 /* Save most if not all of trap frame. */ 387 sf.sf_siginfo.si_sc.sc_eax = regs->tf_rax; 388 sf.sf_siginfo.si_sc.sc_ebx = regs->tf_rbx; 389 sf.sf_siginfo.si_sc.sc_ecx = regs->tf_rcx; 390 sf.sf_siginfo.si_sc.sc_edx = regs->tf_rdx; 391 sf.sf_siginfo.si_sc.sc_esi = regs->tf_rsi; 392 sf.sf_siginfo.si_sc.sc_edi = regs->tf_rdi; 393 sf.sf_siginfo.si_sc.sc_cs = regs->tf_cs; 394 sf.sf_siginfo.si_sc.sc_ds = regs->tf_ds; 395 sf.sf_siginfo.si_sc.sc_ss = regs->tf_ss; 396 sf.sf_siginfo.si_sc.sc_es = regs->tf_es; 397 sf.sf_siginfo.si_sc.sc_fs = regs->tf_fs; 398 sf.sf_siginfo.si_sc.sc_gs = regs->tf_gs; 399 sf.sf_siginfo.si_sc.sc_isp = regs->tf_rsp; 400 401 /* Build the signal context to be used by osigreturn(). */ 402 sf.sf_siginfo.si_sc.sc_onstack = (oonstack) ? 1 : 0; 403 SIG2OSIG(*mask, sf.sf_siginfo.si_sc.sc_mask); 404 sf.sf_siginfo.si_sc.sc_esp = regs->tf_rsp; 405 sf.sf_siginfo.si_sc.sc_ebp = regs->tf_rbp; 406 sf.sf_siginfo.si_sc.sc_eip = regs->tf_rip; 407 sf.sf_siginfo.si_sc.sc_eflags = regs->tf_rflags; 408 sf.sf_siginfo.si_sc.sc_trapno = regs->tf_trapno; 409 sf.sf_siginfo.si_sc.sc_err = regs->tf_err; 410 411 /* 412 * Copy the sigframe out to the user's stack. 413 */ 414 if (copyout(&sf, fp, sizeof(*fp)) != 0) { 415 #ifdef DEBUG 416 printf("process %ld has trashed its stack\n", (long)p->p_pid); 417 #endif 418 PROC_LOCK(p); 419 sigexit(td, SIGILL); 420 } 421 422 regs->tf_rsp = (uintptr_t)fp; 423 regs->tf_rip = PROC_PS_STRINGS(p) - 424 (_binary_elf_vdso32_so_1_end - _binary_elf_vdso32_so_1_start) + 425 VDSO_IA32_OSIGCODE_OFFSET; 426 regs->tf_rflags &= ~(PSL_T | PSL_D); 427 regs->tf_cs = _ucode32sel; 428 regs->tf_ds = _udatasel; 429 regs->tf_es = _udatasel; 430 regs->tf_fs = _udatasel; 431 regs->tf_ss = _udatasel; 432 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 433 PROC_LOCK(p); 434 mtx_lock(&psp->ps_mtx); 435 } 436 #endif 437 438 #ifdef COMPAT_FREEBSD4 439 static void 440 freebsd4_ia32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 441 { 442 struct ia32_freebsd4_sigframe sf, *sfp; 443 struct siginfo32 siginfo; 444 struct proc *p; 445 struct thread *td; 446 struct sigacts *psp; 447 struct trapframe *regs; 448 int oonstack; 449 int sig; 450 451 td = curthread; 452 p = td->td_proc; 453 siginfo_to_siginfo32(&ksi->ksi_info, &siginfo); 454 455 PROC_LOCK_ASSERT(p, MA_OWNED); 456 sig = siginfo.si_signo; 457 psp = p->p_sigacts; 458 mtx_assert(&psp->ps_mtx, MA_OWNED); 459 regs = td->td_frame; 460 oonstack = sigonstack(regs->tf_rsp); 461 462 /* Save user context. */ 463 bzero(&sf, sizeof(sf)); 464 sf.sf_uc.uc_sigmask = *mask; 465 sf.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp; 466 sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size; 467 sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 468 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; 469 sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0; 470 sf.sf_uc.uc_mcontext.mc_edi = regs->tf_rdi; 471 sf.sf_uc.uc_mcontext.mc_esi = regs->tf_rsi; 472 sf.sf_uc.uc_mcontext.mc_ebp = regs->tf_rbp; 473 sf.sf_uc.uc_mcontext.mc_isp = regs->tf_rsp; /* XXX */ 474 sf.sf_uc.uc_mcontext.mc_ebx = regs->tf_rbx; 475 sf.sf_uc.uc_mcontext.mc_edx = regs->tf_rdx; 476 sf.sf_uc.uc_mcontext.mc_ecx = regs->tf_rcx; 477 sf.sf_uc.uc_mcontext.mc_eax = regs->tf_rax; 478 sf.sf_uc.uc_mcontext.mc_trapno = regs->tf_trapno; 479 sf.sf_uc.uc_mcontext.mc_err = regs->tf_err; 480 sf.sf_uc.uc_mcontext.mc_eip = regs->tf_rip; 481 sf.sf_uc.uc_mcontext.mc_cs = regs->tf_cs; 482 sf.sf_uc.uc_mcontext.mc_eflags = regs->tf_rflags; 483 sf.sf_uc.uc_mcontext.mc_esp = regs->tf_rsp; 484 sf.sf_uc.uc_mcontext.mc_ss = regs->tf_ss; 485 sf.sf_uc.uc_mcontext.mc_ds = regs->tf_ds; 486 sf.sf_uc.uc_mcontext.mc_es = regs->tf_es; 487 sf.sf_uc.uc_mcontext.mc_fs = regs->tf_fs; 488 sf.sf_uc.uc_mcontext.mc_gs = regs->tf_gs; 489 bzero(sf.sf_uc.uc_mcontext.mc_fpregs, 490 sizeof(sf.sf_uc.uc_mcontext.mc_fpregs)); 491 bzero(sf.sf_uc.uc_mcontext.__spare__, 492 sizeof(sf.sf_uc.uc_mcontext.__spare__)); 493 bzero(sf.sf_uc.__spare__, sizeof(sf.sf_uc.__spare__)); 494 495 /* Allocate space for the signal handler context. */ 496 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 497 SIGISMEMBER(psp->ps_sigonstack, sig)) { 498 sfp = (struct ia32_freebsd4_sigframe *)((uintptr_t)td->td_sigstk.ss_sp + 499 td->td_sigstk.ss_size - sizeof(sf)); 500 } else 501 sfp = (struct ia32_freebsd4_sigframe *)regs->tf_rsp - 1; 502 PROC_UNLOCK(p); 503 504 /* Build the argument list for the signal handler. */ 505 sf.sf_signum = sig; 506 sf.sf_ucontext = (register_t)&sfp->sf_uc; 507 bzero(&sf.sf_si, sizeof(sf.sf_si)); 508 if (SIGISMEMBER(psp->ps_siginfo, sig)) { 509 /* Signal handler installed with SA_SIGINFO. */ 510 sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si; 511 sf.sf_ah = (u_int32_t)(uintptr_t)catcher; 512 513 /* Fill in POSIX parts */ 514 sf.sf_si = siginfo; 515 sf.sf_si.si_signo = sig; 516 } else { 517 /* Old FreeBSD-style arguments. */ 518 sf.sf_siginfo = siginfo.si_code; 519 sf.sf_addr = (u_int32_t)siginfo.si_addr; 520 sf.sf_ah = (u_int32_t)(uintptr_t)catcher; 521 } 522 mtx_unlock(&psp->ps_mtx); 523 524 /* 525 * Copy the sigframe out to the user's stack. 526 */ 527 if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { 528 #ifdef DEBUG 529 printf("process %ld has trashed its stack\n", (long)p->p_pid); 530 #endif 531 PROC_LOCK(p); 532 sigexit(td, SIGILL); 533 } 534 535 regs->tf_rsp = (uintptr_t)sfp; 536 regs->tf_rip = PROC_SIGCODE(p) + 537 VDSO_FREEBSD4_IA32_SIGCODE_OFFSET - VDSO_IA32_SIGCODE_OFFSET; 538 regs->tf_rflags &= ~(PSL_T | PSL_D); 539 regs->tf_cs = _ucode32sel; 540 regs->tf_ss = _udatasel; 541 regs->tf_ds = _udatasel; 542 regs->tf_es = _udatasel; 543 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 544 /* leave user %fs and %gs untouched */ 545 PROC_LOCK(p); 546 mtx_lock(&psp->ps_mtx); 547 } 548 #endif /* COMPAT_FREEBSD4 */ 549 550 void 551 ia32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 552 { 553 struct ia32_sigframe sf, *sfp; 554 struct siginfo32 siginfo; 555 struct proc *p; 556 struct thread *td; 557 struct sigacts *psp; 558 char *sp; 559 struct trapframe *regs; 560 char *xfpusave; 561 size_t xfpusave_len; 562 int oonstack; 563 int sig; 564 565 siginfo_to_siginfo32(&ksi->ksi_info, &siginfo); 566 td = curthread; 567 p = td->td_proc; 568 PROC_LOCK_ASSERT(p, MA_OWNED); 569 sig = siginfo.si_signo; 570 psp = p->p_sigacts; 571 #ifdef COMPAT_FREEBSD4 572 if (SIGISMEMBER(psp->ps_freebsd4, sig)) { 573 freebsd4_ia32_sendsig(catcher, ksi, mask); 574 return; 575 } 576 #endif 577 #ifdef COMPAT_43 578 if (SIGISMEMBER(psp->ps_osigset, sig)) { 579 ia32_osendsig(catcher, ksi, mask); 580 return; 581 } 582 #endif 583 mtx_assert(&psp->ps_mtx, MA_OWNED); 584 regs = td->td_frame; 585 oonstack = sigonstack(regs->tf_rsp); 586 587 /* Save user context. */ 588 bzero(&sf, sizeof(sf)); 589 sf.sf_uc.uc_sigmask = *mask; 590 sf.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp; 591 sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size; 592 sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) 593 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; 594 sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0; 595 sf.sf_uc.uc_mcontext.mc_edi = regs->tf_rdi; 596 sf.sf_uc.uc_mcontext.mc_esi = regs->tf_rsi; 597 sf.sf_uc.uc_mcontext.mc_ebp = regs->tf_rbp; 598 sf.sf_uc.uc_mcontext.mc_isp = regs->tf_rsp; /* XXX */ 599 sf.sf_uc.uc_mcontext.mc_ebx = regs->tf_rbx; 600 sf.sf_uc.uc_mcontext.mc_edx = regs->tf_rdx; 601 sf.sf_uc.uc_mcontext.mc_ecx = regs->tf_rcx; 602 sf.sf_uc.uc_mcontext.mc_eax = regs->tf_rax; 603 sf.sf_uc.uc_mcontext.mc_trapno = regs->tf_trapno; 604 sf.sf_uc.uc_mcontext.mc_err = regs->tf_err; 605 sf.sf_uc.uc_mcontext.mc_eip = regs->tf_rip; 606 sf.sf_uc.uc_mcontext.mc_cs = regs->tf_cs; 607 sf.sf_uc.uc_mcontext.mc_eflags = regs->tf_rflags; 608 sf.sf_uc.uc_mcontext.mc_esp = regs->tf_rsp; 609 sf.sf_uc.uc_mcontext.mc_ss = regs->tf_ss; 610 sf.sf_uc.uc_mcontext.mc_ds = regs->tf_ds; 611 sf.sf_uc.uc_mcontext.mc_es = regs->tf_es; 612 sf.sf_uc.uc_mcontext.mc_fs = regs->tf_fs; 613 sf.sf_uc.uc_mcontext.mc_gs = regs->tf_gs; 614 sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */ 615 ia32_get_fpcontext(td, &sf.sf_uc.uc_mcontext, &xfpusave, &xfpusave_len); 616 sf.sf_uc.uc_mcontext.mc_fsbase = td->td_pcb->pcb_fsbase; 617 sf.sf_uc.uc_mcontext.mc_gsbase = td->td_pcb->pcb_gsbase; 618 619 /* Allocate space for the signal handler context. */ 620 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 621 SIGISMEMBER(psp->ps_sigonstack, sig)) 622 sp = (char *)td->td_sigstk.ss_sp + td->td_sigstk.ss_size; 623 else 624 sp = (char *)regs->tf_rsp; 625 if (xfpusave != NULL) { 626 sp -= xfpusave_len; 627 sp = (char *)((unsigned long)sp & ~0x3Ful); 628 sf.sf_uc.uc_mcontext.mc_xfpustate = (register_t)sp; 629 } 630 sp -= sizeof(sf); 631 /* Align to 16 bytes. */ 632 sfp = (struct ia32_sigframe *)((uintptr_t)sp & ~0xF); 633 PROC_UNLOCK(p); 634 635 /* Build the argument list for the signal handler. */ 636 sf.sf_signum = sig; 637 sf.sf_ucontext = (register_t)&sfp->sf_uc; 638 bzero(&sf.sf_si, sizeof(sf.sf_si)); 639 if (SIGISMEMBER(psp->ps_siginfo, sig)) { 640 /* Signal handler installed with SA_SIGINFO. */ 641 sf.sf_siginfo = (u_int32_t)(uintptr_t)&sfp->sf_si; 642 sf.sf_ah = (u_int32_t)(uintptr_t)catcher; 643 644 /* Fill in POSIX parts */ 645 sf.sf_si = siginfo; 646 sf.sf_si.si_signo = sig; 647 } else { 648 /* Old FreeBSD-style arguments. */ 649 sf.sf_siginfo = siginfo.si_code; 650 sf.sf_addr = (u_int32_t)siginfo.si_addr; 651 sf.sf_ah = (u_int32_t)(uintptr_t)catcher; 652 } 653 mtx_unlock(&psp->ps_mtx); 654 655 /* 656 * Copy the sigframe out to the user's stack. 657 */ 658 if (copyout(&sf, sfp, sizeof(*sfp)) != 0 || 659 (xfpusave != NULL && copyout(xfpusave, 660 PTRIN(sf.sf_uc.uc_mcontext.mc_xfpustate), xfpusave_len) 661 != 0)) { 662 #ifdef DEBUG 663 printf("process %ld has trashed its stack\n", (long)p->p_pid); 664 #endif 665 PROC_LOCK(p); 666 sigexit(td, SIGILL); 667 } 668 669 fpstate_drop(td); 670 regs->tf_rsp = (uintptr_t)sfp; 671 regs->tf_rip = PROC_SIGCODE(p); 672 regs->tf_rflags &= ~(PSL_T | PSL_D); 673 regs->tf_cs = _ucode32sel; 674 regs->tf_ss = _udatasel; 675 regs->tf_ds = _udatasel; 676 regs->tf_es = _udatasel; 677 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 678 /* XXXKIB leave user %fs and %gs untouched */ 679 PROC_LOCK(p); 680 mtx_lock(&psp->ps_mtx); 681 } 682 683 /* 684 * System call to cleanup state after a signal 685 * has been taken. Reset signal mask and 686 * stack state from context left by sendsig (above). 687 * Return to previous pc and psl as specified by 688 * context left by sendsig. Check carefully to 689 * make sure that the user has not modified the 690 * state to gain improper privileges. 691 */ 692 693 #ifdef COMPAT_43 694 int 695 ofreebsd32_sigreturn(struct thread *td, struct ofreebsd32_sigreturn_args *uap) 696 { 697 struct ia32_osigcontext sc, *scp; 698 struct trapframe *regs; 699 int eflags, error; 700 ksiginfo_t ksi; 701 702 regs = td->td_frame; 703 error = copyin(uap->sigcntxp, &sc, sizeof(sc)); 704 if (error != 0) 705 return (error); 706 scp = ≻ 707 eflags = scp->sc_eflags; 708 if (!EFL_SECURE(eflags, regs->tf_rflags)) { 709 return (EINVAL); 710 } 711 if (!CS_SECURE(scp->sc_cs)) { 712 ksiginfo_init_trap(&ksi); 713 ksi.ksi_signo = SIGBUS; 714 ksi.ksi_code = BUS_OBJERR; 715 ksi.ksi_trapno = T_PROTFLT; 716 ksi.ksi_addr = (void *)regs->tf_rip; 717 trapsignal(td, &ksi); 718 return (EINVAL); 719 } 720 regs->tf_ds = scp->sc_ds; 721 regs->tf_es = scp->sc_es; 722 regs->tf_fs = scp->sc_fs; 723 regs->tf_gs = scp->sc_gs; 724 725 regs->tf_rax = scp->sc_eax; 726 regs->tf_rbx = scp->sc_ebx; 727 regs->tf_rcx = scp->sc_ecx; 728 regs->tf_rdx = scp->sc_edx; 729 regs->tf_rsi = scp->sc_esi; 730 regs->tf_rdi = scp->sc_edi; 731 regs->tf_cs = scp->sc_cs; 732 regs->tf_ss = scp->sc_ss; 733 regs->tf_rbp = scp->sc_ebp; 734 regs->tf_rsp = scp->sc_esp; 735 regs->tf_rip = scp->sc_eip; 736 regs->tf_rflags = eflags; 737 738 if (scp->sc_onstack & 1) 739 td->td_sigstk.ss_flags |= SS_ONSTACK; 740 else 741 td->td_sigstk.ss_flags &= ~SS_ONSTACK; 742 743 kern_sigprocmask(td, SIG_SETMASK, (sigset_t *)&scp->sc_mask, NULL, 744 SIGPROCMASK_OLD); 745 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 746 return (EJUSTRETURN); 747 } 748 #endif 749 750 #ifdef COMPAT_FREEBSD4 751 int 752 freebsd4_freebsd32_sigreturn(struct thread *td, 753 struct freebsd4_freebsd32_sigreturn_args *uap) 754 { 755 struct ia32_freebsd4_ucontext uc; 756 struct trapframe *regs; 757 struct ia32_freebsd4_ucontext *ucp; 758 int cs, eflags, error; 759 ksiginfo_t ksi; 760 761 error = copyin(uap->sigcntxp, &uc, sizeof(uc)); 762 if (error != 0) 763 return (error); 764 ucp = &uc; 765 regs = td->td_frame; 766 eflags = ucp->uc_mcontext.mc_eflags; 767 /* 768 * Don't allow users to change privileged or reserved flags. 769 */ 770 if (!EFL_SECURE(eflags, regs->tf_rflags)) { 771 uprintf("pid %d (%s): freebsd4_freebsd32_sigreturn eflags = 0x%x\n", 772 td->td_proc->p_pid, td->td_name, eflags); 773 return (EINVAL); 774 } 775 776 /* 777 * Don't allow users to load a valid privileged %cs. Let the 778 * hardware check for invalid selectors, excess privilege in 779 * other selectors, invalid %eip's and invalid %esp's. 780 */ 781 cs = ucp->uc_mcontext.mc_cs; 782 if (!CS_SECURE(cs)) { 783 uprintf("pid %d (%s): freebsd4_sigreturn cs = 0x%x\n", 784 td->td_proc->p_pid, td->td_name, cs); 785 ksiginfo_init_trap(&ksi); 786 ksi.ksi_signo = SIGBUS; 787 ksi.ksi_code = BUS_OBJERR; 788 ksi.ksi_trapno = T_PROTFLT; 789 ksi.ksi_addr = (void *)regs->tf_rip; 790 trapsignal(td, &ksi); 791 return (EINVAL); 792 } 793 794 regs->tf_rdi = ucp->uc_mcontext.mc_edi; 795 regs->tf_rsi = ucp->uc_mcontext.mc_esi; 796 regs->tf_rbp = ucp->uc_mcontext.mc_ebp; 797 regs->tf_rbx = ucp->uc_mcontext.mc_ebx; 798 regs->tf_rdx = ucp->uc_mcontext.mc_edx; 799 regs->tf_rcx = ucp->uc_mcontext.mc_ecx; 800 regs->tf_rax = ucp->uc_mcontext.mc_eax; 801 regs->tf_trapno = ucp->uc_mcontext.mc_trapno; 802 regs->tf_err = ucp->uc_mcontext.mc_err; 803 regs->tf_rip = ucp->uc_mcontext.mc_eip; 804 regs->tf_cs = cs; 805 regs->tf_rflags = ucp->uc_mcontext.mc_eflags; 806 regs->tf_rsp = ucp->uc_mcontext.mc_esp; 807 regs->tf_ss = ucp->uc_mcontext.mc_ss; 808 regs->tf_ds = ucp->uc_mcontext.mc_ds; 809 regs->tf_es = ucp->uc_mcontext.mc_es; 810 regs->tf_fs = ucp->uc_mcontext.mc_fs; 811 regs->tf_gs = ucp->uc_mcontext.mc_gs; 812 813 kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0); 814 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 815 return (EJUSTRETURN); 816 } 817 #endif /* COMPAT_FREEBSD4 */ 818 819 int 820 freebsd32_sigreturn(struct thread *td, struct freebsd32_sigreturn_args *uap) 821 { 822 struct ia32_ucontext uc; 823 struct trapframe *regs; 824 struct ia32_ucontext *ucp; 825 char *xfpustate; 826 size_t xfpustate_len; 827 int cs, eflags, error, ret; 828 ksiginfo_t ksi; 829 830 error = copyin(uap->sigcntxp, &uc, sizeof(uc)); 831 if (error != 0) 832 return (error); 833 ucp = &uc; 834 regs = td->td_frame; 835 eflags = ucp->uc_mcontext.mc_eflags; 836 /* 837 * Don't allow users to change privileged or reserved flags. 838 */ 839 if (!EFL_SECURE(eflags, regs->tf_rflags)) { 840 uprintf("pid %d (%s): freebsd32_sigreturn eflags = 0x%x\n", 841 td->td_proc->p_pid, td->td_name, eflags); 842 return (EINVAL); 843 } 844 845 /* 846 * Don't allow users to load a valid privileged %cs. Let the 847 * hardware check for invalid selectors, excess privilege in 848 * other selectors, invalid %eip's and invalid %esp's. 849 */ 850 cs = ucp->uc_mcontext.mc_cs; 851 if (!CS_SECURE(cs)) { 852 uprintf("pid %d (%s): sigreturn cs = 0x%x\n", 853 td->td_proc->p_pid, td->td_name, cs); 854 ksiginfo_init_trap(&ksi); 855 ksi.ksi_signo = SIGBUS; 856 ksi.ksi_code = BUS_OBJERR; 857 ksi.ksi_trapno = T_PROTFLT; 858 ksi.ksi_addr = (void *)regs->tf_rip; 859 trapsignal(td, &ksi); 860 return (EINVAL); 861 } 862 863 if ((ucp->uc_mcontext.mc_flags & _MC_HASFPXSTATE) != 0) { 864 xfpustate_len = uc.uc_mcontext.mc_xfpustate_len; 865 if (xfpustate_len > cpu_max_ext_state_size - 866 sizeof(struct savefpu)) { 867 uprintf("pid %d (%s): sigreturn xfpusave_len = 0x%zx\n", 868 td->td_proc->p_pid, td->td_name, xfpustate_len); 869 return (EINVAL); 870 } 871 xfpustate = (char *)fpu_save_area_alloc(); 872 error = copyin(PTRIN(ucp->uc_mcontext.mc_xfpustate), 873 xfpustate, xfpustate_len); 874 if (error != 0) { 875 fpu_save_area_free((struct savefpu *)xfpustate); 876 uprintf( 877 "pid %d (%s): sigreturn copying xfpustate failed\n", 878 td->td_proc->p_pid, td->td_name); 879 return (error); 880 } 881 } else { 882 xfpustate = NULL; 883 xfpustate_len = 0; 884 } 885 ret = ia32_set_fpcontext(td, &ucp->uc_mcontext, xfpustate, 886 xfpustate_len); 887 fpu_save_area_free((struct savefpu *)xfpustate); 888 if (ret != 0) { 889 uprintf("pid %d (%s): sigreturn set_fpcontext err %d\n", 890 td->td_proc->p_pid, td->td_name, ret); 891 return (ret); 892 } 893 894 regs->tf_rdi = ucp->uc_mcontext.mc_edi; 895 regs->tf_rsi = ucp->uc_mcontext.mc_esi; 896 regs->tf_rbp = ucp->uc_mcontext.mc_ebp; 897 regs->tf_rbx = ucp->uc_mcontext.mc_ebx; 898 regs->tf_rdx = ucp->uc_mcontext.mc_edx; 899 regs->tf_rcx = ucp->uc_mcontext.mc_ecx; 900 regs->tf_rax = ucp->uc_mcontext.mc_eax; 901 regs->tf_trapno = ucp->uc_mcontext.mc_trapno; 902 regs->tf_err = ucp->uc_mcontext.mc_err; 903 regs->tf_rip = ucp->uc_mcontext.mc_eip; 904 regs->tf_cs = cs; 905 regs->tf_rflags = ucp->uc_mcontext.mc_eflags; 906 regs->tf_rsp = ucp->uc_mcontext.mc_esp; 907 regs->tf_ss = ucp->uc_mcontext.mc_ss; 908 regs->tf_ds = ucp->uc_mcontext.mc_ds; 909 regs->tf_es = ucp->uc_mcontext.mc_es; 910 regs->tf_fs = ucp->uc_mcontext.mc_fs; 911 regs->tf_gs = ucp->uc_mcontext.mc_gs; 912 regs->tf_flags = TF_HASSEGS; 913 914 kern_sigprocmask(td, SIG_SETMASK, &ucp->uc_sigmask, NULL, 0); 915 set_pcb_flags(td->td_pcb, PCB_FULL_IRET); 916 return (EJUSTRETURN); 917 } 918 919 /* 920 * Clear registers on exec 921 */ 922 void 923 ia32_setregs(struct thread *td, struct image_params *imgp, uintptr_t stack) 924 { 925 struct trapframe *regs; 926 struct pcb *pcb; 927 register_t saved_rflags; 928 929 regs = td->td_frame; 930 pcb = td->td_pcb; 931 932 if (td->td_proc->p_md.md_ldt != NULL) 933 user_ldt_free(td); 934 #ifdef COMPAT_43 935 setup_lcall_gate(); 936 #endif 937 938 pcb->pcb_fsbase = 0; 939 pcb->pcb_gsbase = 0; 940 pcb->pcb_initial_fpucw = __INITIAL_FPUCW_I386__; 941 942 saved_rflags = regs->tf_rflags & PSL_T; 943 bzero((char *)regs, sizeof(struct trapframe)); 944 regs->tf_rip = imgp->entry_addr; 945 regs->tf_rsp = stack; 946 regs->tf_rflags = PSL_USER | saved_rflags; 947 regs->tf_ss = _udatasel; 948 regs->tf_cs = _ucode32sel; 949 regs->tf_rbx = (register_t)imgp->ps_strings; 950 regs->tf_ds = _udatasel; 951 regs->tf_es = _udatasel; 952 regs->tf_fs = _ufssel; 953 regs->tf_gs = _ugssel; 954 regs->tf_flags = TF_HASSEGS; 955 956 x86_clear_dbregs(pcb); 957 958 fpstate_drop(td); 959 960 /* Return via doreti so that we can change to a different %cs */ 961 set_pcb_flags(pcb, PCB_32BIT | PCB_FULL_IRET); 962 } 963