1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */ 28 /* Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T */ 29 /* All Rights Reserved */ 30 31 #pragma ident "%Z%%M% %I% %E% SMI" 32 33 #include <sys/types.h> 34 #include <sys/param.h> 35 #include <sys/sysmacros.h> 36 #include <sys/signal.h> 37 #include <sys/systm.h> 38 #include <sys/user.h> 39 #include <sys/mman.h> 40 #include <sys/class.h> 41 #include <sys/proc.h> 42 #include <sys/procfs.h> 43 #include <sys/buf.h> 44 #include <sys/kmem.h> 45 #include <sys/cred.h> 46 #include <sys/archsystm.h> 47 #include <sys/vmparam.h> 48 #include <sys/prsystm.h> 49 #include <sys/reboot.h> 50 #include <sys/uadmin.h> 51 #include <sys/vfs.h> 52 #include <sys/vnode.h> 53 #include <sys/file.h> 54 #include <sys/session.h> 55 #include <sys/ucontext.h> 56 #include <sys/dnlc.h> 57 #include <sys/var.h> 58 #include <sys/cmn_err.h> 59 #include <sys/debugreg.h> 60 #include <sys/thread.h> 61 #include <sys/vtrace.h> 62 #include <sys/consdev.h> 63 #include <sys/psw.h> 64 #include <sys/regset.h> 65 66 #include <sys/privregs.h> 67 68 #include <sys/stack.h> 69 #include <sys/swap.h> 70 #include <vm/hat.h> 71 #include <vm/anon.h> 72 #include <vm/as.h> 73 #include <vm/page.h> 74 #include <vm/seg.h> 75 #include <vm/seg_kmem.h> 76 #include <vm/seg_map.h> 77 #include <vm/seg_vn.h> 78 #include <sys/exec.h> 79 #include <sys/acct.h> 80 #include <sys/core.h> 81 #include <sys/corectl.h> 82 #include <sys/modctl.h> 83 #include <sys/tuneable.h> 84 #include <c2/audit.h> 85 #include <sys/bootconf.h> 86 #include <sys/dumphdr.h> 87 #include <sys/promif.h> 88 #include <sys/systeminfo.h> 89 #include <sys/kdi.h> 90 #include <sys/contract_impl.h> 91 #include <sys/x86_archext.h> 92 93 /* 94 * Construct the execution environment for the user's signal 95 * handler and arrange for control to be given to it on return 96 * to userland. The library code now calls setcontext() to 97 * clean up after the signal handler, so sigret() is no longer 98 * needed. 99 * 100 * (The various 'volatile' declarations are need to ensure that values 101 * are correct on the error return from on_fault().) 102 */ 103 104 #if defined(__amd64) 105 106 /* 107 * An amd64 signal frame looks like this on the stack: 108 * 109 * old %rsp: 110 * <128 bytes of untouched stack space> 111 * <a siginfo_t [optional]> 112 * <a ucontext_t> 113 * <siginfo_t *> 114 * <signal number> 115 * new %rsp: <return address (deliberately invalid)> 116 * 117 * The signal number and siginfo_t pointer are only pushed onto the stack in 118 * order to allow stack backtraces. The actual signal handling code expects the 119 * arguments in registers. 120 */ 121 122 struct sigframe { 123 caddr_t retaddr; 124 long signo; 125 siginfo_t *sip; 126 }; 127 128 int 129 sendsig(int sig, k_siginfo_t *sip, void (*hdlr)()) 130 { 131 volatile int minstacksz; 132 int newstack; 133 label_t ljb; 134 volatile caddr_t sp; 135 caddr_t fp; 136 volatile struct regs *rp; 137 volatile greg_t upc; 138 volatile proc_t *p = ttoproc(curthread); 139 klwp_t *lwp = ttolwp(curthread); 140 ucontext_t *volatile tuc = NULL; 141 ucontext_t *uc; 142 siginfo_t *sip_addr; 143 volatile int watched; 144 145 /* 146 * This routine is utterly dependent upon STACK_ALIGN being 147 * 16 and STACK_ENTRY_ALIGN being 8. Let's just acknowledge 148 * that and require it. 149 */ 150 151 #if STACK_ALIGN != 16 || STACK_ENTRY_ALIGN != 8 152 #error "sendsig() amd64 did not find the expected stack alignments" 153 #endif 154 155 rp = lwptoregs(lwp); 156 upc = rp->r_pc; 157 158 /* 159 * Since we're setting up to run the signal handler we have to 160 * arrange that the stack at entry to the handler is (only) 161 * STACK_ENTRY_ALIGN (i.e. 8) byte aligned so that when the handler 162 * executes its push of %rbp, the stack realigns to STACK_ALIGN 163 * (i.e. 16) correctly. 164 * 165 * The new sp will point to the sigframe and the ucontext_t. The 166 * above means that sp (and thus sigframe) will be 8-byte aligned, 167 * but not 16-byte aligned. ucontext_t, however, contains %xmm regs 168 * which must be 16-byte aligned. Because of this, for correct 169 * alignment, sigframe must be a multiple of 8-bytes in length, but 170 * not 16-bytes. This will place ucontext_t at a nice 16-byte boundary. 171 */ 172 173 /* LINTED: logical expression always true: op "||" */ 174 ASSERT((sizeof (struct sigframe) % 16) == 8); 175 176 minstacksz = sizeof (struct sigframe) + SA(sizeof (*uc)); 177 if (sip != NULL) 178 minstacksz += SA(sizeof (siginfo_t)); 179 ASSERT((minstacksz & (STACK_ENTRY_ALIGN - 1ul)) == 0); 180 181 /* 182 * Figure out whether we will be handling this signal on 183 * an alternate stack specified by the user. Then allocate 184 * and validate the stack requirements for the signal handler 185 * context. on_fault will catch any faults. 186 */ 187 newstack = sigismember(&u.u_sigonstack, sig) && 188 !(lwp->lwp_sigaltstack.ss_flags & (SS_ONSTACK|SS_DISABLE)); 189 190 if (newstack) { 191 fp = (caddr_t)(SA((uintptr_t)lwp->lwp_sigaltstack.ss_sp) + 192 SA(lwp->lwp_sigaltstack.ss_size) - STACK_ALIGN); 193 } else { 194 /* 195 * Drop below the 128-byte reserved region of the stack frame 196 * we're interrupting. 197 */ 198 fp = (caddr_t)rp->r_sp - STACK_RESERVE; 199 } 200 201 /* 202 * Most of the time during normal execution, the stack pointer 203 * is aligned on a STACK_ALIGN (i.e. 16 byte) boundary. However, 204 * (for example) just after a call instruction (which pushes 205 * the return address), the callers stack misaligns until the 206 * 'push %rbp' happens in the callee prolog. So while we should 207 * expect the stack pointer to be always at least STACK_ENTRY_ALIGN 208 * aligned, we should -not- expect it to always be STACK_ALIGN aligned. 209 * We now adjust to ensure that the new sp is aligned to 210 * STACK_ENTRY_ALIGN but not to STACK_ALIGN. 211 */ 212 sp = fp - minstacksz; 213 if (((uintptr_t)sp & (STACK_ALIGN - 1ul)) == 0) { 214 sp -= STACK_ENTRY_ALIGN; 215 minstacksz = fp - sp; 216 } 217 218 /* 219 * Now, make sure the resulting signal frame address is sane 220 */ 221 if (((uintptr_t)(sp - STACK_ENTRY_ALIGN) & (STACK_ALIGN - 1ul)) != 0 || 222 sp >= (caddr_t)USERLIMIT || fp >= (caddr_t)USERLIMIT) { 223 #ifdef DEBUG 224 printf("sendsig: bad signal stack cmd=%s, pid=%d, sig=%d\n", 225 PTOU(p)->u_comm, p->p_pid, sig); 226 printf("sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n", 227 (void *)sp, (void *)hdlr, (uintptr_t)upc); 228 229 if (((uintptr_t)(sp - STACK_ENTRY_ALIGN) & 230 (STACK_ALIGN - 1ul)) != 0) 231 printf("bad stack alignment\n"); 232 else 233 printf("sp above USERLIMIT\n"); 234 #endif 235 return (0); 236 } 237 238 watched = watch_disable_addr((caddr_t)sp, minstacksz, S_WRITE); 239 240 if (on_fault(&ljb)) 241 goto badstack; 242 243 if (sip != NULL) { 244 zoneid_t zoneid; 245 246 fp -= SA(sizeof (siginfo_t)); 247 uzero(fp, sizeof (siginfo_t)); 248 if (SI_FROMUSER(sip) && 249 (zoneid = p->p_zone->zone_id) != GLOBAL_ZONEID && 250 zoneid != sip->si_zoneid) { 251 k_siginfo_t sani_sip = *sip; 252 253 sani_sip.si_pid = p->p_zone->zone_zsched->p_pid; 254 sani_sip.si_uid = 0; 255 sani_sip.si_ctid = -1; 256 sani_sip.si_zoneid = zoneid; 257 copyout_noerr(&sani_sip, fp, sizeof (sani_sip)); 258 } else 259 copyout_noerr(sip, fp, sizeof (*sip)); 260 sip_addr = (siginfo_t *)fp; 261 262 if (sig == SIGPROF && 263 curthread->t_rprof != NULL && 264 curthread->t_rprof->rp_anystate) { 265 /* 266 * We stand on our head to deal with 267 * the real time profiling signal. 268 * Fill in the stuff that doesn't fit 269 * in a normal k_siginfo structure. 270 */ 271 int i = sip->si_nsysarg; 272 273 while (--i >= 0) 274 sulword_noerr( 275 (ulong_t *)&(sip_addr->si_sysarg[i]), 276 (ulong_t)lwp->lwp_arg[i]); 277 copyout_noerr(curthread->t_rprof->rp_state, 278 sip_addr->si_mstate, 279 sizeof (curthread->t_rprof->rp_state)); 280 } 281 } else 282 sip_addr = NULL; 283 284 /* 285 * save the current context on the user stack directly after the 286 * sigframe. Since sigframe is 8-byte-but-not-16-byte aligned, 287 * and since sizeof (struct sigframe) is 24, this guarantees 288 * 16-byte alignment for ucontext_t and its %xmm registers. 289 */ 290 uc = (ucontext_t *)(sp + sizeof (struct sigframe)); 291 tuc = kmem_alloc(sizeof (*tuc), KM_SLEEP); 292 savecontext(tuc, lwp->lwp_sigoldmask); 293 copyout_noerr(tuc, uc, sizeof (*tuc)); 294 kmem_free(tuc, sizeof (*tuc)); 295 tuc = NULL; 296 297 lwp->lwp_oldcontext = (uintptr_t)uc; 298 299 if (newstack) { 300 lwp->lwp_sigaltstack.ss_flags |= SS_ONSTACK; 301 if (lwp->lwp_ustack) 302 copyout_noerr(&lwp->lwp_sigaltstack, 303 (stack_t *)lwp->lwp_ustack, sizeof (stack_t)); 304 } 305 306 /* 307 * Set up signal handler return and stack linkage 308 */ 309 { 310 struct sigframe frame; 311 312 /* 313 * ensure we never return "normally" 314 */ 315 frame.retaddr = (caddr_t)(uintptr_t)-1L; 316 frame.signo = sig; 317 frame.sip = sip_addr; 318 copyout_noerr(&frame, sp, sizeof (frame)); 319 } 320 321 no_fault(); 322 if (watched) 323 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE); 324 325 /* 326 * Set up user registers for execution of signal handler. 327 */ 328 rp->r_sp = (greg_t)sp; 329 rp->r_pc = (greg_t)hdlr; 330 rp->r_ps = PSL_USER | (rp->r_ps & PS_IOPL); 331 332 rp->r_rdi = sig; 333 rp->r_rsi = (uintptr_t)sip_addr; 334 rp->r_rdx = (uintptr_t)uc; 335 336 if ((rp->r_cs & 0xffff) != UCS_SEL || 337 (rp->r_ss & 0xffff) != UDS_SEL) { 338 /* 339 * Try our best to deliver the signal. 340 */ 341 rp->r_cs = UCS_SEL; 342 rp->r_ss = UDS_SEL; 343 } 344 345 /* 346 * Don't set lwp_eosys here. sendsig() is called via psig() after 347 * lwp_eosys is handled, so setting it here would affect the next 348 * system call. 349 */ 350 return (1); 351 352 badstack: 353 no_fault(); 354 if (watched) 355 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE); 356 if (tuc) 357 kmem_free(tuc, sizeof (*tuc)); 358 #ifdef DEBUG 359 printf("sendsig: bad signal stack cmd=%s, pid=%d, sig=%d\n", 360 PTOU(p)->u_comm, p->p_pid, sig); 361 printf("on fault, sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n", 362 (void *)sp, (void *)hdlr, (uintptr_t)upc); 363 #endif 364 return (0); 365 } 366 367 #ifdef _SYSCALL32_IMPL 368 369 /* 370 * An i386 SVR4/ABI signal frame looks like this on the stack: 371 * 372 * old %esp: 373 * <a siginfo32_t [optional]> 374 * <a ucontext32_t> 375 * <pointer to that ucontext32_t> 376 * <pointer to that siginfo32_t> 377 * <signo> 378 * new %esp: <return address (deliberately invalid)> 379 */ 380 struct sigframe32 { 381 caddr32_t retaddr; 382 uint32_t signo; 383 caddr32_t sip; 384 caddr32_t ucp; 385 }; 386 387 int 388 sendsig32(int sig, k_siginfo_t *sip, void (*hdlr)()) 389 { 390 volatile int minstacksz; 391 int newstack; 392 label_t ljb; 393 volatile caddr_t sp; 394 caddr_t fp; 395 volatile struct regs *rp; 396 volatile greg_t upc; 397 volatile proc_t *p = ttoproc(curthread); 398 klwp_t *lwp = ttolwp(curthread); 399 ucontext32_t *volatile tuc = NULL; 400 ucontext32_t *uc; 401 siginfo32_t *sip_addr; 402 volatile int watched; 403 404 rp = lwptoregs(lwp); 405 upc = rp->r_pc; 406 407 minstacksz = SA32(sizeof (struct sigframe32)) + SA32(sizeof (*uc)); 408 if (sip != NULL) 409 minstacksz += SA32(sizeof (siginfo32_t)); 410 ASSERT((minstacksz & (STACK_ALIGN32 - 1)) == 0); 411 412 /* 413 * Figure out whether we will be handling this signal on 414 * an alternate stack specified by the user. Then allocate 415 * and validate the stack requirements for the signal handler 416 * context. on_fault will catch any faults. 417 */ 418 newstack = sigismember(&u.u_sigonstack, sig) && 419 !(lwp->lwp_sigaltstack.ss_flags & (SS_ONSTACK|SS_DISABLE)); 420 421 if (newstack) { 422 fp = (caddr_t)(SA32((uintptr_t)lwp->lwp_sigaltstack.ss_sp) + 423 SA32(lwp->lwp_sigaltstack.ss_size) - STACK_ALIGN32); 424 } else if ((rp->r_ss & 0xffff) != UDS_SEL) { 425 user_desc_t *ldt; 426 /* 427 * If the stack segment selector is -not- pointing at 428 * the UDS_SEL descriptor and we have an LDT entry for 429 * it instead, add the base address to find the effective va. 430 */ 431 if ((ldt = p->p_ldt) != NULL) 432 fp = (caddr_t)rp->r_sp + 433 USEGD_GETBASE(&ldt[SELTOIDX(rp->r_ss)]); 434 else 435 fp = (caddr_t)rp->r_sp; 436 } else 437 fp = (caddr_t)rp->r_sp; 438 sp = fp - minstacksz; 439 440 /* 441 * Make sure lwp hasn't trashed its stack 442 */ 443 if (((uintptr_t)sp & (STACK_ALIGN32 - 1)) != 0 || 444 sp >= (caddr_t)(uintptr_t)USERLIMIT32 || 445 fp >= (caddr_t)(uintptr_t)USERLIMIT32) { 446 #ifdef DEBUG 447 printf("sendsig32: bad signal stack cmd=%s, pid=%d, sig=%d\n", 448 PTOU(p)->u_comm, p->p_pid, sig); 449 printf("sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n", 450 (void *)sp, (void *)hdlr, (uintptr_t)upc); 451 452 if (((uintptr_t)sp & (STACK_ALIGN32 - 1)) != 0) 453 printf("bad stack alignment\n"); 454 else 455 printf("sp above USERLIMIT\n"); 456 #endif 457 return (0); 458 } 459 460 watched = watch_disable_addr((caddr_t)sp, minstacksz, S_WRITE); 461 462 if (on_fault(&ljb)) 463 goto badstack; 464 465 if (sip != NULL) { 466 siginfo32_t si32; 467 zoneid_t zoneid; 468 469 siginfo_kto32(sip, &si32); 470 if (SI_FROMUSER(sip) && 471 (zoneid = p->p_zone->zone_id) != GLOBAL_ZONEID && 472 zoneid != sip->si_zoneid) { 473 si32.si_pid = p->p_zone->zone_zsched->p_pid; 474 si32.si_uid = 0; 475 si32.si_ctid = -1; 476 si32.si_zoneid = zoneid; 477 } 478 fp -= SA32(sizeof (si32)); 479 uzero(fp, sizeof (si32)); 480 copyout_noerr(&si32, fp, sizeof (si32)); 481 sip_addr = (siginfo32_t *)fp; 482 483 if (sig == SIGPROF && 484 curthread->t_rprof != NULL && 485 curthread->t_rprof->rp_anystate) { 486 /* 487 * We stand on our head to deal with 488 * the real-time profiling signal. 489 * Fill in the stuff that doesn't fit 490 * in a normal k_siginfo structure. 491 */ 492 int i = sip->si_nsysarg; 493 494 while (--i >= 0) 495 suword32_noerr(&(sip_addr->si_sysarg[i]), 496 (uint32_t)lwp->lwp_arg[i]); 497 copyout_noerr(curthread->t_rprof->rp_state, 498 sip_addr->si_mstate, 499 sizeof (curthread->t_rprof->rp_state)); 500 } 501 } else 502 sip_addr = NULL; 503 504 /* save the current context on the user stack */ 505 fp -= SA32(sizeof (*tuc)); 506 uc = (ucontext32_t *)fp; 507 tuc = kmem_alloc(sizeof (*tuc), KM_SLEEP); 508 savecontext32(tuc, lwp->lwp_sigoldmask); 509 copyout_noerr(tuc, uc, sizeof (*tuc)); 510 kmem_free(tuc, sizeof (*tuc)); 511 tuc = NULL; 512 513 lwp->lwp_oldcontext = (uintptr_t)uc; 514 515 if (newstack) { 516 lwp->lwp_sigaltstack.ss_flags |= SS_ONSTACK; 517 if (lwp->lwp_ustack) { 518 stack32_t stk32; 519 520 stk32.ss_sp = (caddr32_t)(uintptr_t) 521 lwp->lwp_sigaltstack.ss_sp; 522 stk32.ss_size = (size32_t) 523 lwp->lwp_sigaltstack.ss_size; 524 stk32.ss_flags = (int32_t) 525 lwp->lwp_sigaltstack.ss_flags; 526 copyout_noerr(&stk32, 527 (stack32_t *)lwp->lwp_ustack, sizeof (stk32)); 528 } 529 } 530 531 /* 532 * Set up signal handler arguments 533 */ 534 { 535 struct sigframe32 frame32; 536 537 frame32.sip = (caddr32_t)(uintptr_t)sip_addr; 538 frame32.ucp = (caddr32_t)(uintptr_t)uc; 539 frame32.signo = sig; 540 frame32.retaddr = 0xffffffff; /* never return! */ 541 copyout_noerr(&frame32, sp, sizeof (frame32)); 542 } 543 544 no_fault(); 545 if (watched) 546 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE); 547 548 rp->r_sp = (greg_t)(uintptr_t)sp; 549 rp->r_pc = (greg_t)(uintptr_t)hdlr; 550 rp->r_ps = PSL_USER | (rp->r_ps & PS_IOPL); 551 552 if ((rp->r_cs & 0xffff) != U32CS_SEL || 553 (rp->r_ss & 0xffff) != UDS_SEL) { 554 /* 555 * Try our best to deliver the signal. 556 */ 557 rp->r_cs = U32CS_SEL; 558 rp->r_ss = UDS_SEL; 559 } 560 561 /* 562 * Don't set lwp_eosys here. sendsig() is called via psig() after 563 * lwp_eosys is handled, so setting it here would affect the next 564 * system call. 565 */ 566 return (1); 567 568 badstack: 569 no_fault(); 570 if (watched) 571 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE); 572 if (tuc) 573 kmem_free(tuc, sizeof (*tuc)); 574 #ifdef DEBUG 575 printf("sendsig32: bad signal stack cmd=%s pid=%d, sig=%d\n", 576 PTOU(p)->u_comm, p->p_pid, sig); 577 printf("on fault, sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n", 578 (void *)sp, (void *)hdlr, (uintptr_t)upc); 579 #endif 580 return (0); 581 } 582 583 #endif /* _SYSCALL32_IMPL */ 584 585 #elif defined(__i386) 586 587 /* 588 * An i386 SVR4/ABI signal frame looks like this on the stack: 589 * 590 * old %esp: 591 * <a siginfo32_t [optional]> 592 * <a ucontext32_t> 593 * <pointer to that ucontext32_t> 594 * <pointer to that siginfo32_t> 595 * <signo> 596 * new %esp: <return address (deliberately invalid)> 597 */ 598 struct sigframe { 599 void (*retaddr)(); 600 uint_t signo; 601 siginfo_t *sip; 602 ucontext_t *ucp; 603 }; 604 605 int 606 sendsig(int sig, k_siginfo_t *sip, void (*hdlr)()) 607 { 608 volatile int minstacksz; 609 int newstack; 610 label_t ljb; 611 volatile caddr_t sp; 612 caddr_t fp; 613 struct regs *rp; 614 volatile greg_t upc; 615 volatile proc_t *p = ttoproc(curthread); 616 klwp_t *lwp = ttolwp(curthread); 617 ucontext_t *volatile tuc = NULL; 618 ucontext_t *uc; 619 siginfo_t *sip_addr; 620 volatile int watched; 621 622 rp = lwptoregs(lwp); 623 upc = rp->r_pc; 624 625 minstacksz = SA(sizeof (struct sigframe)) + SA(sizeof (*uc)); 626 if (sip != NULL) 627 minstacksz += SA(sizeof (siginfo_t)); 628 ASSERT((minstacksz & (STACK_ALIGN - 1ul)) == 0); 629 630 /* 631 * Figure out whether we will be handling this signal on 632 * an alternate stack specified by the user. Then allocate 633 * and validate the stack requirements for the signal handler 634 * context. on_fault will catch any faults. 635 */ 636 newstack = sigismember(&u.u_sigonstack, sig) && 637 !(lwp->lwp_sigaltstack.ss_flags & (SS_ONSTACK|SS_DISABLE)); 638 639 if (newstack) { 640 fp = (caddr_t)(SA((uintptr_t)lwp->lwp_sigaltstack.ss_sp) + 641 SA(lwp->lwp_sigaltstack.ss_size) - STACK_ALIGN); 642 } else if ((rp->r_ss & 0xffff) != UDS_SEL) { 643 user_desc_t *ldt; 644 /* 645 * If the stack segment selector is -not- pointing at 646 * the UDS_SEL descriptor and we have an LDT entry for 647 * it instead, add the base address to find the effective va. 648 */ 649 if ((ldt = p->p_ldt) != NULL) 650 fp = (caddr_t)rp->r_sp + 651 USEGD_GETBASE(&ldt[SELTOIDX(rp->r_ss)]); 652 else 653 fp = (caddr_t)rp->r_sp; 654 } else 655 fp = (caddr_t)rp->r_sp; 656 sp = fp - minstacksz; 657 658 /* 659 * Make sure lwp hasn't trashed its stack. 660 */ 661 if (((uintptr_t)sp & (STACK_ALIGN - 1ul)) != 0 || 662 sp >= (caddr_t)USERLIMIT || fp >= (caddr_t)USERLIMIT) { 663 #ifdef DEBUG 664 printf("sendsig: bad signal stack cmd=%s, pid=%d, sig=%d\n", 665 PTOU(p)->u_comm, p->p_pid, sig); 666 printf("sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n", 667 (void *)sp, (void *)hdlr, (uintptr_t)upc); 668 669 if (((uintptr_t)sp & (STACK_ALIGN - 1ul)) != 0) 670 printf("bad stack alignment\n"); 671 else 672 printf("sp above USERLIMIT\n"); 673 #endif 674 return (0); 675 } 676 677 watched = watch_disable_addr((caddr_t)sp, minstacksz, S_WRITE); 678 679 if (on_fault(&ljb)) 680 goto badstack; 681 682 if (sip != NULL) { 683 zoneid_t zoneid; 684 685 fp -= SA(sizeof (siginfo_t)); 686 uzero(fp, sizeof (siginfo_t)); 687 if (SI_FROMUSER(sip) && 688 (zoneid = p->p_zone->zone_id) != GLOBAL_ZONEID && 689 zoneid != sip->si_zoneid) { 690 k_siginfo_t sani_sip = *sip; 691 692 sani_sip.si_pid = p->p_zone->zone_zsched->p_pid; 693 sani_sip.si_uid = 0; 694 sani_sip.si_ctid = -1; 695 sani_sip.si_zoneid = zoneid; 696 copyout_noerr(&sani_sip, fp, sizeof (sani_sip)); 697 } else 698 copyout_noerr(sip, fp, sizeof (*sip)); 699 sip_addr = (siginfo_t *)fp; 700 701 if (sig == SIGPROF && 702 curthread->t_rprof != NULL && 703 curthread->t_rprof->rp_anystate) { 704 /* 705 * We stand on our head to deal with 706 * the real time profiling signal. 707 * Fill in the stuff that doesn't fit 708 * in a normal k_siginfo structure. 709 */ 710 int i = sip->si_nsysarg; 711 712 while (--i >= 0) 713 suword32_noerr(&(sip_addr->si_sysarg[i]), 714 (uint32_t)lwp->lwp_arg[i]); 715 copyout_noerr(curthread->t_rprof->rp_state, 716 sip_addr->si_mstate, 717 sizeof (curthread->t_rprof->rp_state)); 718 } 719 } else 720 sip_addr = NULL; 721 722 /* save the current context on the user stack */ 723 fp -= SA(sizeof (*tuc)); 724 uc = (ucontext_t *)fp; 725 tuc = kmem_alloc(sizeof (*tuc), KM_SLEEP); 726 savecontext(tuc, lwp->lwp_sigoldmask); 727 copyout_noerr(tuc, uc, sizeof (*tuc)); 728 kmem_free(tuc, sizeof (*tuc)); 729 tuc = NULL; 730 731 lwp->lwp_oldcontext = (uintptr_t)uc; 732 733 if (newstack) { 734 lwp->lwp_sigaltstack.ss_flags |= SS_ONSTACK; 735 if (lwp->lwp_ustack) 736 copyout_noerr(&lwp->lwp_sigaltstack, 737 (stack_t *)lwp->lwp_ustack, sizeof (stack_t)); 738 } 739 740 /* 741 * Set up signal handler arguments 742 */ 743 { 744 struct sigframe frame; 745 746 frame.sip = sip_addr; 747 frame.ucp = uc; 748 frame.signo = sig; 749 frame.retaddr = (void (*)())0xffffffff; /* never return! */ 750 copyout_noerr(&frame, sp, sizeof (frame)); 751 } 752 753 no_fault(); 754 if (watched) 755 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE); 756 757 rp->r_sp = (greg_t)sp; 758 rp->r_pc = (greg_t)hdlr; 759 rp->r_ps = PSL_USER | (rp->r_ps & PS_IOPL); 760 761 if ((rp->r_cs & 0xffff) != UCS_SEL || 762 (rp->r_ss & 0xffff) != UDS_SEL) { 763 rp->r_cs = UCS_SEL; 764 rp->r_ss = UDS_SEL; 765 } 766 767 /* 768 * Don't set lwp_eosys here. sendsig() is called via psig() after 769 * lwp_eosys is handled, so setting it here would affect the next 770 * system call. 771 */ 772 return (1); 773 774 badstack: 775 no_fault(); 776 if (watched) 777 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE); 778 if (tuc) 779 kmem_free(tuc, sizeof (*tuc)); 780 #ifdef DEBUG 781 printf("sendsig: bad signal stack cmd=%s, pid=%d, sig=%d\n", 782 PTOU(p)->u_comm, p->p_pid, sig); 783 printf("on fault, sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n", 784 (void *)sp, (void *)hdlr, (uintptr_t)upc); 785 #endif 786 return (0); 787 } 788 789 #endif /* __i386 */ 790