1 2/*--------------------------------------------------------------------*/ 3/*--- Create/destroy signal delivery frames. ---*/ 4/*--- sigframe-ppc32-linux.c ---*/ 5/*--------------------------------------------------------------------*/ 6 7/* 8 This file is part of Valgrind, a dynamic binary instrumentation 9 framework. 10 11 Copyright (C) 2000-2011 Nicholas Nethercote 12 njn@valgrind.org 13 Copyright (C) 2004-2011 Paul Mackerras 14 paulus@samba.org 15 16 This program is free software; you can redistribute it and/or 17 modify it under the terms of the GNU General Public License as 18 published by the Free Software Foundation; either version 2 of the 19 License, or (at your option) any later version. 20 21 This program is distributed in the hope that it will be useful, but 22 WITHOUT ANY WARRANTY; without even the implied warranty of 23 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 24 General Public License for more details. 25 26 You should have received a copy of the GNU General Public License 27 along with this program; if not, write to the Free Software 28 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 29 02111-1307, USA. 30 31 The GNU General Public License is contained in the file COPYING. 32*/ 33 34#if defined(VGP_ppc32_linux) 35 36#include "pub_core_basics.h" 37#include "pub_core_vki.h" 38#include "pub_core_vkiscnums.h" 39#include "pub_core_libcsetjmp.h" // to keep _threadstate.h happy 40#include "pub_core_threadstate.h" 41#include "pub_core_aspacemgr.h" 42#include "pub_core_libcbase.h" 43#include "pub_core_libcassert.h" 44#include "pub_core_libcprint.h" 45#include "pub_core_machine.h" 46#include "pub_core_options.h" 47#include "pub_core_sigframe.h" 48#include "pub_core_signals.h" 49#include "pub_core_tooliface.h" 50#include "pub_core_trampoline.h" 51#include "pub_core_transtab.h" // VG_(discard_translations) 52 53 54/* This module creates and removes signal frames for signal deliveries 55 on ppc32-linux. 56 57 Note, this file contains kernel-specific knowledge in the form of 58 'struct sigframe' and 'struct rt_sigframe'. How does that relate 59 to the vki kernel interface stuff? 60 61 Either a 'struct sigframe' or a 'struct rtsigframe' is pushed 62 onto the client's stack. This contains a subsidiary 63 vki_ucontext. That holds the vcpu's state across the signal, 64 so that the sighandler can mess with the vcpu state if it 65 really wants. 66 67 FIXME: sigcontexting is basically broken for the moment. When 68 delivering a signal, the integer registers and %eflags are 69 correctly written into the sigcontext, however the FP and SSE state 70 is not. When returning from a signal, only the integer registers 71 are restored from the sigcontext; the rest of the CPU state is 72 restored to what it was before the signal. 73 74 This will be fixed. 75*/ 76 77 78/*------------------------------------------------------------*/ 79/*--- Signal frame layouts ---*/ 80/*------------------------------------------------------------*/ 81 82// A structure in which to save the application's registers 83// during the execution of signal handlers. 84 85// Linux has 2 signal frame structures: one for normal signal 86// deliveries, and one for SA_SIGINFO deliveries (also known as RT 87// signals). 88// 89// In theory, so long as we get the arguments to the handler function 90// right, it doesn't matter what the exact layout of the rest of the 91// frame is. Unfortunately, things like gcc's exception unwinding 92// make assumptions about the locations of various parts of the frame, 93// so we need to duplicate it exactly. 94 95/* Structure containing bits of information that we want to save 96 on signal delivery. */ 97struct vg_sig_private { 98 UInt magicPI; 99 UInt sigNo_private; 100 VexGuestPPC32State vex_shadow1; 101 VexGuestPPC32State vex_shadow2; 102}; 103 104/* Structure put on stack for signal handlers with SA_SIGINFO clear. */ 105struct nonrt_sigframe { 106 UInt gap1[16]; 107 struct vki_sigcontext sigcontext; 108 struct vki_mcontext mcontext; 109 struct vg_sig_private priv; 110 unsigned char abigap[224]; 111}; 112 113/* Structure put on stack for signal handlers with SA_SIGINFO set. */ 114struct rt_sigframe { 115 UInt gap1[20]; 116 vki_siginfo_t siginfo; 117 struct vki_ucontext ucontext; 118 struct vg_sig_private priv; 119 unsigned char abigap[224]; 120}; 121 122#define SET_SIGNAL_LR(zztst, zzval) \ 123 do { tst->arch.vex.guest_LR = (zzval); \ 124 VG_TRACK( post_reg_write, Vg_CoreSignal, tst->tid, \ 125 offsetof(VexGuestPPC32State,guest_LR), \ 126 sizeof(UWord) ); \ 127 } while (0) 128 129#define SET_SIGNAL_GPR(zztst, zzn, zzval) \ 130 do { tst->arch.vex.guest_GPR##zzn = (zzval); \ 131 VG_TRACK( post_reg_write, Vg_CoreSignal, tst->tid, \ 132 offsetof(VexGuestPPC32State,guest_GPR##zzn), \ 133 sizeof(UWord) ); \ 134 } while (0) 135 136 137static 138void stack_mcontext ( struct vki_mcontext *mc, 139 ThreadState* tst, 140 Bool use_rt_sigreturn, 141 UInt fault_addr ) 142{ 143 VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "signal frame mcontext", 144 (Addr)mc, sizeof(struct vki_pt_regs) ); 145 146# define DO(gpr) mc->mc_gregs[VKI_PT_R0+gpr] = tst->arch.vex.guest_GPR##gpr 147 DO(0); DO(1); DO(2); DO(3); DO(4); DO(5); DO(6); DO(7); 148 DO(8); DO(9); DO(10); DO(11); DO(12); DO(13); DO(14); DO(15); 149 DO(16); DO(17); DO(18); DO(19); DO(20); DO(21); DO(22); DO(23); 150 DO(24); DO(25); DO(26); DO(27); DO(28); DO(29); DO(30); DO(31); 151# undef DO 152 153 mc->mc_gregs[VKI_PT_NIP] = tst->arch.vex.guest_CIA; 154 mc->mc_gregs[VKI_PT_MSR] = 0xf032; /* pretty arbitrary */ 155 mc->mc_gregs[VKI_PT_ORIG_R3] = tst->arch.vex.guest_GPR3; 156 mc->mc_gregs[VKI_PT_CTR] = tst->arch.vex.guest_CTR; 157 mc->mc_gregs[VKI_PT_LNK] = tst->arch.vex.guest_LR; 158 mc->mc_gregs[VKI_PT_XER] = LibVEX_GuestPPC32_get_XER(&tst->arch.vex); 159 mc->mc_gregs[VKI_PT_CCR] = LibVEX_GuestPPC32_get_CR(&tst->arch.vex); 160 mc->mc_gregs[VKI_PT_MQ] = 0; 161 mc->mc_gregs[VKI_PT_TRAP] = 0; 162 mc->mc_gregs[VKI_PT_DAR] = fault_addr; 163 mc->mc_gregs[VKI_PT_DSISR] = 0; 164 mc->mc_gregs[VKI_PT_RESULT] = 0; 165 VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid, 166 (Addr)mc, sizeof(struct vki_pt_regs) ); 167 168 /* XXX should do FP and vector regs */ 169 170 /* set up signal return trampoline */ 171 /* NB. 5 Sept 07. mc->mc_pad[0..1] used to contain a the code to 172 which the signal handler returns, and it just did sys_sigreturn 173 or sys_rt_sigreturn. But this doesn't work if the stack is 174 non-executable, and it isn't consistent with the x86-linux and 175 amd64-linux scheme for removing the stack frame. So instead be 176 consistent and use a stub in m_trampoline. Then it doesn't 177 matter whether or not the (guest) stack is executable. This 178 fixes #149519 and #145837. */ 179 VG_TRACK(pre_mem_write, Vg_CoreSignal, tst->tid, "signal frame mcontext", 180 (Addr)&mc->mc_pad, sizeof(mc->mc_pad)); 181 mc->mc_pad[0] = 0; /* invalid */ 182 mc->mc_pad[1] = 0; /* invalid */ 183 VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid, 184 (Addr)&mc->mc_pad, sizeof(mc->mc_pad) ); 185 /* invalidate any translation of this area */ 186 VG_(discard_translations)( (Addr64)(Addr)&mc->mc_pad, 187 sizeof(mc->mc_pad), "stack_mcontext" ); 188 189 /* set the signal handler to return to the trampoline */ 190 SET_SIGNAL_LR(tst, (Addr)(use_rt_sigreturn 191 ? (Addr)&VG_(ppc32_linux_SUBST_FOR_rt_sigreturn) 192 : (Addr)&VG_(ppc32_linux_SUBST_FOR_sigreturn) 193 )); 194} 195 196//:: /* Valgrind-specific parts of the signal frame */ 197//:: struct vg_sigframe 198//:: { 199//:: /* Sanity check word. */ 200//:: UInt magicPI; 201//:: 202//:: UInt handlerflags; /* flags for signal handler */ 203//:: 204//:: 205//:: /* Safely-saved version of sigNo, as described above. */ 206//:: Int sigNo_private; 207//:: 208//:: /* XXX This is wrong. Surely we should store the shadow values 209//:: into the shadow memory behind the actual values? */ 210//:: VexGuestPPC32State vex_shadow; 211//:: 212//:: /* HACK ALERT */ 213//:: VexGuestPPC32State vex; 214//:: /* end HACK ALERT */ 215//:: 216//:: /* saved signal mask to be restored when handler returns */ 217//:: vki_sigset_t mask; 218//:: 219//:: /* Sanity check word. Is the highest-addressed word; do not 220//:: move!*/ 221//:: UInt magicE; 222//:: }; 223//:: 224//:: struct sigframe 225//:: { 226//:: /* Sig handler's return address */ 227//:: Addr retaddr; 228//:: Int sigNo; 229//:: 230//:: struct vki_sigcontext sigContext; 231//:: //.. struct _vki_fpstate fpstate; 232//:: 233//:: struct vg_sigframe vg; 234//:: }; 235//:: 236//:: struct rt_sigframe 237//:: { 238//:: /* Sig handler's return address */ 239//:: Addr retaddr; 240//:: Int sigNo; 241//:: 242//:: /* ptr to siginfo_t. */ 243//:: Addr psigInfo; 244//:: 245//:: /* ptr to ucontext */ 246//:: Addr puContext; 247//:: /* pointed to by psigInfo */ 248//:: vki_siginfo_t sigInfo; 249//:: 250//:: /* pointed to by puContext */ 251//:: struct vki_ucontext uContext; 252//:: //.. struct _vki_fpstate fpstate; 253//:: 254//:: struct vg_sigframe vg; 255//:: }; 256 257 258//:: /*------------------------------------------------------------*/ 259//:: /*--- Signal operations ---*/ 260//:: /*------------------------------------------------------------*/ 261//:: 262//:: /* 263//:: Great gobs of FP state conversion taken wholesale from 264//:: linux/arch/i386/kernel/i387.c 265//:: */ 266//:: 267//:: /* 268//:: * FXSR floating point environment conversions. 269//:: */ 270//:: #define X86_FXSR_MAGIC 0x0000 271//:: 272//:: /* 273//:: * FPU tag word conversions. 274//:: */ 275//:: 276//:: static inline unsigned short twd_i387_to_fxsr( unsigned short twd ) 277//:: { 278//:: unsigned int tmp; /* to avoid 16 bit prefixes in the code */ 279//:: 280//:: /* Transform each pair of bits into 01 (valid) or 00 (empty) */ 281//:: tmp = ~twd; 282//:: tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */ 283//:: /* and move the valid bits to the lower byte. */ 284//:: tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */ 285//:: tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */ 286//:: tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */ 287//:: return tmp; 288//:: } 289//:: 290//:: static unsigned long twd_fxsr_to_i387( const struct i387_fxsave_struct *fxsave ) 291//:: { 292//:: struct _vki_fpxreg *st = NULL; 293//:: unsigned long twd = (unsigned long) fxsave->twd; 294//:: unsigned long tag; 295//:: unsigned long ret = 0xffff0000u; 296//:: int i; 297//:: 298//:: #define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16); 299//:: 300//:: for ( i = 0 ; i < 8 ; i++ ) { 301//:: if ( twd & 0x1 ) { 302//:: st = (struct _vki_fpxreg *) FPREG_ADDR( fxsave, i ); 303//:: 304//:: switch ( st->exponent & 0x7fff ) { 305//:: case 0x7fff: 306//:: tag = 2; /* Special */ 307//:: break; 308//:: case 0x0000: 309//:: if ( !st->significand[0] && 310//:: !st->significand[1] && 311//:: !st->significand[2] && 312//:: !st->significand[3] ) { 313//:: tag = 1; /* Zero */ 314//:: } else { 315//:: tag = 2; /* Special */ 316//:: } 317//:: break; 318//:: default: 319//:: if ( st->significand[3] & 0x8000 ) { 320//:: tag = 0; /* Valid */ 321//:: } else { 322//:: tag = 2; /* Special */ 323//:: } 324//:: break; 325//:: } 326//:: } else { 327//:: tag = 3; /* Empty */ 328//:: } 329//:: ret |= (tag << (2 * i)); 330//:: twd = twd >> 1; 331//:: } 332//:: return ret; 333//:: } 334//:: 335//:: static void convert_fxsr_to_user( struct _vki_fpstate *buf, 336//:: const struct i387_fxsave_struct *fxsave ) 337//:: { 338//:: unsigned long env[7]; 339//:: struct _vki_fpreg *to; 340//:: struct _vki_fpxreg *from; 341//:: int i; 342//:: 343//:: env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul; 344//:: env[1] = (unsigned long)fxsave->swd | 0xffff0000ul; 345//:: env[2] = twd_fxsr_to_i387(fxsave); 346//:: env[3] = fxsave->fip; 347//:: env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16); 348//:: env[5] = fxsave->foo; 349//:: env[6] = fxsave->fos; 350//:: 351//:: VG_(memcpy)(buf, env, 7 * sizeof(unsigned long)); 352//:: 353//:: to = &buf->_st[0]; 354//:: from = (struct _vki_fpxreg *) &fxsave->st_space[0]; 355//:: for ( i = 0 ; i < 8 ; i++, to++, from++ ) { 356//:: unsigned long __user *t = (unsigned long __user *)to; 357//:: unsigned long *f = (unsigned long *)from; 358//:: 359//:: t[0] = f[0]; 360//:: t[1] = f[1]; 361//:: to->exponent = from->exponent; 362//:: } 363//:: } 364//:: 365//:: static void convert_fxsr_from_user( struct i387_fxsave_struct *fxsave, 366//:: const struct _vki_fpstate *buf ) 367//:: { 368//:: unsigned long env[7]; 369//:: struct _vki_fpxreg *to; 370//:: const struct _vki_fpreg *from; 371//:: int i; 372//:: 373//:: VG_(memcpy)(env, buf, 7 * sizeof(long)); 374//:: 375//:: fxsave->cwd = (unsigned short)(env[0] & 0xffff); 376//:: fxsave->swd = (unsigned short)(env[1] & 0xffff); 377//:: fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff)); 378//:: fxsave->fip = env[3]; 379//:: fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16); 380//:: fxsave->fcs = (env[4] & 0xffff); 381//:: fxsave->foo = env[5]; 382//:: fxsave->fos = env[6]; 383//:: 384//:: to = (struct _vki_fpxreg *) &fxsave->st_space[0]; 385//:: from = &buf->_st[0]; 386//:: for ( i = 0 ; i < 8 ; i++, to++, from++ ) { 387//:: unsigned long *t = (unsigned long *)to; 388//:: unsigned long __user *f = (unsigned long __user *)from; 389//:: 390//:: t[0] = f[0]; 391//:: t[1] = f[1]; 392//:: to->exponent = from->exponent; 393//:: } 394//:: } 395//:: 396//:: static inline void save_i387_fsave( arch_thread_t *regs, struct _vki_fpstate *buf ) 397//:: { 398//:: struct i387_fsave_struct *fs = ®s->m_sse.fsave; 399//:: 400//:: fs->status = fs->swd; 401//:: VG_(memcpy)(buf, fs, sizeof(*fs)); 402//:: } 403//:: 404//:: static void save_i387_fxsave( arch_thread_t *regs, struct _vki_fpstate *buf ) 405//:: { 406//:: const struct i387_fxsave_struct *fx = ®s->m_sse.fxsave; 407//:: convert_fxsr_to_user( buf, fx ); 408//:: 409//:: buf->status = fx->swd; 410//:: buf->magic = X86_FXSR_MAGIC; 411//:: VG_(memcpy)(buf->_fxsr_env, fx, sizeof(struct i387_fxsave_struct)); 412//:: } 413//:: 414//:: static void save_i387( arch_thread_t *regs, struct _vki_fpstate *buf ) 415//:: { 416//:: if ( VG_(have_ssestate) ) 417//:: save_i387_fxsave( regs, buf ); 418//:: else 419//:: save_i387_fsave( regs, buf ); 420//:: } 421//:: 422//:: static inline void restore_i387_fsave( arch_thread_t *regs, const struct _vki_fpstate __user *buf ) 423//:: { 424//:: VG_(memcpy)( ®s->m_sse.fsave, buf, sizeof(struct i387_fsave_struct) ); 425//:: } 426//:: 427//:: static void restore_i387_fxsave( arch_thread_t *regs, const struct _vki_fpstate __user *buf ) 428//:: { 429//:: VG_(memcpy)(®s->m_sse.fxsave, &buf->_fxsr_env[0], 430//:: sizeof(struct i387_fxsave_struct) ); 431//:: /* mxcsr reserved bits must be masked to zero for security reasons */ 432//:: regs->m_sse.fxsave.mxcsr &= 0xffbf; 433//:: convert_fxsr_from_user( ®s->m_sse.fxsave, buf ); 434//:: } 435//:: 436//:: static void restore_i387( arch_thread_t *regs, const struct _vki_fpstate __user *buf ) 437//:: { 438//:: if ( VG_(have_ssestate) ) { 439//:: restore_i387_fxsave( regs, buf ); 440//:: } else { 441//:: restore_i387_fsave( regs, buf ); 442//:: } 443//:: } 444 445 446 447 448/*------------------------------------------------------------*/ 449/*--- Creating signal frames ---*/ 450/*------------------------------------------------------------*/ 451 452//.. /* Create a plausible-looking sigcontext from the thread's 453//.. Vex guest state. NOTE: does not fill in the FP or SSE 454//.. bits of sigcontext at the moment. 455//.. */ 456//.. static 457//.. void synth_ucontext(ThreadId tid, const vki_siginfo_t *si, 458//.. const vki_sigset_t *set, struct vki_ucontext *uc) 459//.. { 460//.. ThreadState *tst = VG_(get_ThreadState)(tid); 461//.. struct vki_sigcontext *sc = &uc->uc_mcontext; 462//.. 463//.. VG_(memset)(uc, 0, sizeof(*uc)); 464//.. 465//.. uc->uc_flags = 0; 466//.. uc->uc_link = 0; 467//.. uc->uc_sigmask = *set; 468//.. uc->uc_stack = tst->altstack; 469//.. sc->fpstate = fpstate; 470//.. 471//.. // FIXME: save_i387(&tst->arch, fpstate); 472//.. 473//.. # define SC2(reg,REG) sc->reg = tst->arch.vex.guest_##REG 474//.. SC2(gs,GS); 475//.. SC2(fs,FS); 476//.. SC2(es,ES); 477//.. SC2(ds,DS); 478//.. 479//.. SC2(edi,EDI); 480//.. SC2(esi,ESI); 481//.. SC2(ebp,EBP); 482//.. SC2(esp,ESP); 483//.. SC2(ebx,EBX); 484//.. SC2(edx,EDX); 485//.. SC2(ecx,ECX); 486//.. SC2(eax,EAX); 487//.. 488//.. SC2(eip,EIP); 489//.. SC2(cs,CS); 490//.. sc->eflags = LibVEX_GuestX86_get_eflags(&tst->arch.vex); 491//.. SC2(ss,SS); 492//.. /* XXX esp_at_signal */ 493//.. /* XXX trapno */ 494//.. /* XXX err */ 495//.. # undef SC2 496//.. 497//.. sc->cr2 = (UInt)si->_sifields._sigfault._addr; 498//.. } 499/* 500//.. #define SET_SIGNAL_ESP(zztid, zzval) \ 501//.. SET_THREAD_REG(zztid, zzval, STACK_PTR, post_reg_write, \ 502//.. Vg_CoreSignal, zztid, VG_O_STACK_PTR, sizeof(Addr)) 503*/ 504 505/* Extend the stack segment downwards if needed so as to ensure the 506 new signal frames are mapped to something. Return a Bool 507 indicating whether or not the operation was successful. 508*/ 509static Bool extend ( ThreadState *tst, Addr addr, SizeT size ) 510{ 511 ThreadId tid = tst->tid; 512 NSegment const* stackseg = NULL; 513 514 if (VG_(extend_stack)(addr, tst->client_stack_szB)) { 515 stackseg = VG_(am_find_nsegment)(addr); 516 if (0 && stackseg) 517 VG_(printf)("frame=%#lx seg=%#lx-%#lx\n", 518 addr, stackseg->start, stackseg->end); 519 } 520 521 if (stackseg == NULL || !stackseg->hasR || !stackseg->hasW) { 522 VG_(message)( 523 Vg_UserMsg, 524 "Can't extend stack to %#lx during signal delivery for thread %d:\n", 525 addr, tid); 526 if (stackseg == NULL) 527 VG_(message)(Vg_UserMsg, " no stack segment\n"); 528 else 529 VG_(message)(Vg_UserMsg, " too small or bad protection modes\n"); 530 531 /* set SIGSEGV to default handler */ 532 VG_(set_default_handler)(VKI_SIGSEGV); 533 VG_(synth_fault_mapping)(tid, addr); 534 535 /* The whole process should be about to die, since the default 536 action of SIGSEGV to kill the whole process. */ 537 return False; 538 } 539 540 /* For tracking memory events, indicate the entire frame has been 541 allocated. */ 542 VG_TRACK( new_mem_stack_signal, addr - VG_STACK_REDZONE_SZB, 543 size + VG_STACK_REDZONE_SZB, tid ); 544 545 return True; 546} 547 548//.. /* Build the Valgrind-specific part of a signal frame. */ 549//.. 550//.. static void build_vg_sigframe(struct vg_sigframe *frame, 551//.. ThreadState *tst, 552//.. const vki_sigset_t *mask, 553//.. UInt flags, 554//.. Int sigNo) 555//.. { 556//.. frame->sigNo_private = sigNo; 557//.. frame->magicPI = 0x31415927; 558//.. frame->vex_shadow = tst->arch.vex_shadow; 559//.. /* HACK ALERT */ 560//.. frame->vex = tst->arch.vex; 561//.. /* end HACK ALERT */ 562//.. frame->mask = tst->sig_mask; 563//.. frame->handlerflags = flags; 564//.. frame->magicE = 0x27182818; 565//.. } 566 567 568//.. static Addr build_sigframe(ThreadState *tst, 569//.. Addr esp_top_of_frame, 570//.. const vki_siginfo_t *siginfo, 571//.. void *handler, UInt flags, 572//.. const vki_sigset_t *mask, 573//.. void *restorer) 574//.. { 575//.. struct sigframe *frame; 576//.. Addr esp = esp_top_of_frame; 577//.. Int sigNo = siginfo->si_signo; 578//.. struct vki_ucontext uc; 579//.. 580//.. vg_assert((flags & VKI_SA_SIGINFO) == 0); 581//.. 582//.. esp -= sizeof(*frame); 583//.. esp = ROUNDDN(esp, 16); 584//.. frame = (struct sigframe *)esp; 585//.. 586//.. if (!extend(tst, esp, sizeof(*frame))) 587//.. return esp_top_of_frame; 588//.. 589//.. /* retaddr, sigNo, siguContext fields are to be written */ 590//.. VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "signal handler frame", 591//.. esp, offsetof(struct sigframe, vg) ); 592//.. 593//.. frame->sigNo = sigNo; 594//.. 595//.. if (flags & VKI_SA_RESTORER) 596//.. frame->retaddr = (Addr)restorer; 597//.. else 598//.. frame->retaddr 599//.. = VG_(client_trampoline_code)+VG_(tramp_sigreturn_offset); 600//.. 601//.. synth_ucontext(tst->tid, siginfo, mask, &uc, &frame->fpstate); 602//.. 603//.. VG_(memcpy)(&frame->sigContext, &uc.uc_mcontext, 604//.. sizeof(struct vki_sigcontext)); 605//.. frame->sigContext.oldmask = mask->sig[0]; 606//.. 607//.. VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid, 608//.. esp, offsetof(struct sigframe, vg) ); 609//.. 610//.. build_vg_sigframe(&frame->vg, tst, mask, flags, sigNo); 611//.. 612//.. return esp; 613//.. } 614 615 616//.. static Addr build_rt_sigframe(ThreadState *tst, 617//.. Addr esp_top_of_frame, 618//.. const vki_siginfo_t *siginfo, 619//.. void *handler, UInt flags, 620//.. const vki_sigset_t *mask, 621//.. void *restorer) 622//.. { 623//.. struct rt_sigframe *frame; 624//.. Addr esp = esp_top_of_frame; 625//.. Int sigNo = siginfo->si_signo; 626//.. 627//.. vg_assert((flags & VKI_SA_SIGINFO) != 0); 628//.. 629//.. esp -= sizeof(*frame); 630//.. esp = ROUNDDN(esp, 16); 631//.. frame = (struct rt_sigframe *)esp; 632//.. 633//.. if (!extend(tst, esp, sizeof(*frame))) 634//.. return esp_top_of_frame; 635//.. 636//.. /* retaddr, sigNo, pSiginfo, puContext fields are to be written */ 637//.. VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "rt signal handler frame", 638//.. esp, offsetof(struct rt_sigframe, vg) ); 639//.. 640//.. frame->sigNo = sigNo; 641//.. 642//.. if (flags & VKI_SA_RESTORER) 643//.. frame->retaddr = (Addr)restorer; 644//.. else 645//.. frame->retaddr 646//.. = VG_(client_trampoline_code)+VG_(tramp_rt_sigreturn_offset); 647//.. 648//.. frame->psigInfo = (Addr)&frame->sigInfo; 649//.. frame->puContext = (Addr)&frame->uContext; 650//.. VG_(memcpy)(&frame->sigInfo, siginfo, sizeof(vki_siginfo_t)); 651//.. 652//.. /* SIGILL defines addr to be the faulting address */ 653//.. if (sigNo == VKI_SIGILL && siginfo->si_code > 0) 654//.. frame->sigInfo._sifields._sigfault._addr 655//.. = (void*)tst->arch.vex.guest_CIA; 656//.. 657//.. synth_ucontext(tst->tid, siginfo, mask, &frame->uContext, &frame->fpstate); 658//.. 659//.. VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid, 660//.. esp, offsetof(struct rt_sigframe, vg) ); 661//.. 662//.. build_vg_sigframe(&frame->vg, tst, mask, flags, sigNo); 663//.. 664//.. return esp; 665//.. } 666 667 668/* EXPORTED */ 669void VG_(sigframe_create)( ThreadId tid, 670 Addr sp_top_of_frame, 671 const vki_siginfo_t *siginfo, 672 const struct vki_ucontext *siguc, 673 void *handler, 674 UInt flags, 675 const vki_sigset_t *mask, 676 void *restorer ) 677{ 678 struct vg_sig_private *priv; 679 Addr sp; 680 ThreadState *tst; 681 Int sigNo = siginfo->si_signo; 682 Addr faultaddr; 683 684 /* Stack must be 16-byte aligned */ 685 sp_top_of_frame &= ~0xf; 686 687 if (flags & VKI_SA_SIGINFO) { 688 sp = sp_top_of_frame - sizeof(struct rt_sigframe); 689 } else { 690 sp = sp_top_of_frame - sizeof(struct nonrt_sigframe); 691 } 692 693 tst = VG_(get_ThreadState)(tid); 694 695 if (!extend(tst, sp, sp_top_of_frame - sp)) 696 return; 697 698 vg_assert(VG_IS_16_ALIGNED(sp)); 699 700 /* Set up the stack chain pointer */ 701 VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal handler frame", 702 sp, sizeof(UWord) ); 703 *(Addr *)sp = tst->arch.vex.guest_GPR1; 704 VG_TRACK( post_mem_write, Vg_CoreSignal, tid, 705 sp, sizeof(UWord) ); 706 707 faultaddr = (Addr)siginfo->_sifields._sigfault._addr; 708 if (sigNo == VKI_SIGILL && siginfo->si_code > 0) 709 faultaddr = tst->arch.vex.guest_CIA; 710 711 if (flags & VKI_SA_SIGINFO) { 712 struct rt_sigframe *frame = (struct rt_sigframe *) sp; 713 struct vki_ucontext *ucp = &frame->ucontext; 714 715 VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame siginfo", 716 (Addr)&frame->siginfo, sizeof(frame->siginfo) ); 717 VG_(memcpy)(&frame->siginfo, siginfo, sizeof(*siginfo)); 718 VG_TRACK( post_mem_write, Vg_CoreSignal, tid, 719 (Addr)&frame->siginfo, sizeof(frame->siginfo) ); 720 721 VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame ucontext", 722 (Addr)ucp, offsetof(struct vki_ucontext, uc_pad) ); 723 ucp->uc_flags = 0; 724 ucp->uc_link = 0; 725 ucp->uc_stack = tst->altstack; 726 VG_TRACK( post_mem_write, Vg_CoreSignal, tid, (Addr)ucp, 727 offsetof(struct vki_ucontext, uc_pad) ); 728 729 VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame ucontext", 730 (Addr)&ucp->uc_regs, 731 sizeof(ucp->uc_regs) + sizeof(ucp->uc_sigmask) ); 732 ucp->uc_regs = &ucp->uc_mcontext; 733 ucp->uc_sigmask = tst->sig_mask; 734 VG_TRACK( post_mem_write, Vg_CoreSignal, tid, 735 (Addr)&ucp->uc_regs, 736 sizeof(ucp->uc_regs) + sizeof(ucp->uc_sigmask) ); 737 738 stack_mcontext(&ucp->uc_mcontext, tst, True/*use_rt_sigreturn*/, faultaddr); 739 priv = &frame->priv; 740 741 SET_SIGNAL_GPR(tid, 4, (Addr) &frame->siginfo); 742 SET_SIGNAL_GPR(tid, 5, (Addr) ucp); 743 /* the kernel sets this, though it doesn't seem to be in the ABI */ 744 SET_SIGNAL_GPR(tid, 6, (Addr) &frame->siginfo); 745 746 } else { 747 /* non-RT signal delivery */ 748 struct nonrt_sigframe *frame = (struct nonrt_sigframe *) sp; 749 struct vki_sigcontext *scp = &frame->sigcontext; 750 751 VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame sigcontext", 752 (Addr)&scp->_unused[3], sizeof(*scp) - 3 * sizeof(UInt) ); 753 scp->signal = sigNo; 754 scp->handler = (Addr) handler; 755 scp->oldmask = tst->sig_mask.sig[0]; 756 scp->_unused[3] = tst->sig_mask.sig[1]; 757 VG_TRACK( post_mem_write, Vg_CoreSignal, tid, 758 (Addr)&scp->_unused[3], sizeof(*scp) - 3 * sizeof(UInt) ); 759 760 stack_mcontext(&frame->mcontext, tst, False/*!use_rt_sigreturn*/, faultaddr); 761 priv = &frame->priv; 762 763 SET_SIGNAL_GPR(tid, 4, (Addr) scp); 764 } 765 766 priv->magicPI = 0x31415927; 767 priv->sigNo_private = sigNo; 768 priv->vex_shadow1 = tst->arch.vex_shadow1; 769 priv->vex_shadow2 = tst->arch.vex_shadow2; 770 771 SET_SIGNAL_GPR(tid, 1, sp); 772 SET_SIGNAL_GPR(tid, 3, sigNo); 773 tst->arch.vex.guest_CIA = (Addr) handler; 774 775//.. Addr esp; 776//.. ThreadState* tst = VG_(get_ThreadState)(tid); 777//.. 778//.. if (flags & VKI_SA_SIGINFO) 779//.. esp = build_rt_sigframe(tst, esp_top_of_frame, siginfo, 780//.. handler, flags, mask, restorer); 781//.. else 782//.. esp = build_sigframe(tst, esp_top_of_frame, 783//.. siginfo, handler, flags, mask, restorer); 784//.. 785//.. /* Set the thread so it will next run the handler. */ 786//.. /* tst->m_esp = esp; */ 787//.. SET_SIGNAL_ESP(tid, esp); 788//.. 789//.. //VG_(printf)("handler = %p\n", handler); 790//.. tst->arch.vex.guest_CIA = (Addr) handler; 791//.. /* This thread needs to be marked runnable, but we leave that the 792//.. caller to do. */ 793 794 if (0) 795 VG_(printf)("pushed signal frame; %%R1 now = %#lx, " 796 "next %%CIA = %#x, status=%d\n", 797 sp, tst->arch.vex.guest_CIA, tst->status); 798} 799 800 801/*------------------------------------------------------------*/ 802/*--- Destroying signal frames ---*/ 803/*------------------------------------------------------------*/ 804 805//.. /* Return False and don't do anything, just set the client to take a 806//.. segfault, if it looks like the frame is corrupted. */ 807//.. static 808//.. Bool restore_vg_sigframe ( ThreadState *tst, 809//.. struct vg_sigframe *frame, Int *sigNo ) 810//.. { 811//.. if (frame->magicPI != 0x31415927 || 812//.. frame->magicE != 0x27182818) { 813//.. VG_(message)(Vg_UserMsg, "Thread %d return signal frame " 814//.. "corrupted. Killing process.", 815//.. tst->tid); 816//.. VG_(set_default_handler)(VKI_SIGSEGV); 817//.. VG_(synth_fault)(tst->tid); 818//.. *sigNo = VKI_SIGSEGV; 819//.. return False; 820//.. } 821//.. tst->sig_mask = frame->mask; 822//.. tst->tmp_sig_mask = frame->mask; 823//.. tst->arch.vex_shadow = frame->vex_shadow; 824//.. /* HACK ALERT */ 825//.. tst->arch.vex = frame->vex; 826//.. /* end HACK ALERT */ 827//.. *sigNo = frame->sigNo_private; 828//.. return True; 829//.. } 830 831//.. static 832//.. void restore_sigcontext( ThreadState *tst, 833//.. struct vki_sigcontext *sc ) 834//.. //.. struct vki_sigcontext *sc, struct _vki_fpstate *fpstate ) 835//.. { 836//.. tst->arch.vex.guest_EAX = sc->eax; 837//.. tst->arch.vex.guest_ECX = sc->ecx; 838//.. tst->arch.vex.guest_EDX = sc->edx; 839//.. tst->arch.vex.guest_EBX = sc->ebx; 840//.. tst->arch.vex.guest_EBP = sc->ebp; 841//.. tst->arch.vex.guest_ESP = sc->esp; 842//.. tst->arch.vex.guest_ESI = sc->esi; 843//.. tst->arch.vex.guest_EDI = sc->edi; 844//.. //:: tst->arch.vex.guest_eflags = sc->eflags; 845//.. //:: tst->arch.vex.guest_EIP = sc->eip; 846//.. 847//.. tst->arch.vex.guest_CS = sc->cs; 848//.. tst->arch.vex.guest_SS = sc->ss; 849//.. tst->arch.vex.guest_DS = sc->ds; 850//.. tst->arch.vex.guest_ES = sc->es; 851//.. tst->arch.vex.guest_FS = sc->fs; 852//.. tst->arch.vex.guest_GS = sc->gs; 853//.. 854//.. //:: restore_i387(&tst->arch, fpstate); 855//.. } 856 857 858//.. static 859//.. SizeT restore_sigframe ( ThreadState *tst, 860//.. struct sigframe *frame, Int *sigNo ) 861//.. { 862//.. if (restore_vg_sigframe(tst, &frame->vg, sigNo)) 863//.. restore_sigcontext(tst, &frame->sigContext, &frame->fpstate); 864//.. return sizeof(*frame); 865//.. } 866 867//.. static 868//.. SizeT restore_rt_sigframe ( ThreadState *tst, 869//.. struct rt_sigframe *frame, Int *sigNo ) 870//.. { 871//.. if (restore_vg_sigframe(tst, &frame->vg, sigNo)) 872//.. restore_sigcontext(tst, &frame->uContext.uc_mcontext, &frame->fpstate); 873//.. return sizeof(*frame); 874//.. } 875 876 877/* EXPORTED */ 878void VG_(sigframe_destroy)( ThreadId tid, Bool isRT ) 879{ 880 ThreadState *tst; 881 struct vg_sig_private *priv; 882 Addr sp; 883 UInt frame_size; 884 struct vki_mcontext *mc; 885 Int sigNo; 886 Bool has_siginfo = isRT; 887 888 vg_assert(VG_(is_valid_tid)(tid)); 889 tst = VG_(get_ThreadState)(tid); 890 891 /* Check that the stack frame looks valid */ 892 sp = tst->arch.vex.guest_GPR1; 893 vg_assert(VG_IS_16_ALIGNED(sp)); 894 /* JRS 17 Nov 05: This code used to check that *sp -- which should 895 have been set by the stwu at the start of the handler -- points 896 to just above the frame (ie, the previous frame). However, that 897 isn't valid when delivering signals on alt stacks. So I removed 898 it. The frame is still sanity-checked using the priv->magicPI 899 field. */ 900 901 if (has_siginfo) { 902 struct rt_sigframe *frame = (struct rt_sigframe *)sp; 903 frame_size = sizeof(*frame); 904 mc = &frame->ucontext.uc_mcontext; 905 priv = &frame->priv; 906 vg_assert(priv->magicPI == 0x31415927); 907 tst->sig_mask = frame->ucontext.uc_sigmask; 908 } else { 909 struct nonrt_sigframe *frame = (struct nonrt_sigframe *)sp; 910 frame_size = sizeof(*frame); 911 mc = &frame->mcontext; 912 priv = &frame->priv; 913 vg_assert(priv->magicPI == 0x31415927); 914 tst->sig_mask.sig[0] = frame->sigcontext.oldmask; 915 tst->sig_mask.sig[1] = frame->sigcontext._unused[3]; 916 } 917 tst->tmp_sig_mask = tst->sig_mask; 918 919 sigNo = priv->sigNo_private; 920 921# define DO(gpr) tst->arch.vex.guest_GPR##gpr = mc->mc_gregs[VKI_PT_R0+gpr] 922 DO(0); DO(1); DO(2); DO(3); DO(4); DO(5); DO(6); DO(7); 923 DO(8); DO(9); DO(10); DO(11); DO(12); DO(13); DO(14); DO(15); 924 DO(16); DO(17); DO(18); DO(19); DO(20); DO(21); DO(22); DO(23); 925 DO(24); DO(25); DO(26); DO(27); DO(28); DO(29); DO(30); DO(31); 926# undef DO 927 928 tst->arch.vex.guest_CIA = mc->mc_gregs[VKI_PT_NIP]; 929 930 // Umm ... ? (jrs 2005 July 8) 931 // tst->arch.m_orig_gpr3 = mc->mc_gregs[VKI_PT_ORIG_R3]; 932 933 LibVEX_GuestPPC32_put_CR( mc->mc_gregs[VKI_PT_CCR], &tst->arch.vex ); 934 935 tst->arch.vex.guest_LR = mc->mc_gregs[VKI_PT_LNK]; 936 tst->arch.vex.guest_CTR = mc->mc_gregs[VKI_PT_CTR]; 937 LibVEX_GuestPPC32_put_XER( mc->mc_gregs[VKI_PT_XER], &tst->arch.vex ); 938 939 tst->arch.vex_shadow1 = priv->vex_shadow1; 940 tst->arch.vex_shadow2 = priv->vex_shadow2; 941 942 VG_TRACK(die_mem_stack_signal, sp, frame_size); 943 944 if (VG_(clo_trace_signals)) 945 VG_(message)(Vg_DebugMsg, 946 "vg_pop_signal_frame (thread %d): " 947 "isRT=%d valid magic; EIP=%#x\n", 948 tid, has_siginfo, tst->arch.vex.guest_CIA); 949 950 /* tell the tools */ 951 VG_TRACK( post_deliver_signal, tid, sigNo ); 952 953//.. Addr esp; 954//.. ThreadState* tst; 955//.. SizeT size; 956//.. Int sigNo; 957//.. 958//.. tst = VG_(get_ThreadState)(tid); 959//.. 960//.. /* Correctly reestablish the frame base address. */ 961//.. esp = tst->arch.vex.guest_ESP; 962//.. 963//.. if (!isRT) 964//.. size = restore_sigframe(tst, (struct sigframe *)esp, &sigNo); 965//.. else 966//.. size = restore_rt_sigframe(tst, (struct rt_sigframe *)esp, &sigNo); 967//.. 968//.. VG_TRACK( die_mem_stack_signal, esp, size ); 969//.. 970//.. if (VG_(clo_trace_signals)) 971//.. VG_(message)( 972//.. Vg_DebugMsg, 973//.. "VG_(signal_return) (thread %d): isRT=%d valid magic; EIP=%p", 974//.. tid, isRT, tst->arch.vex.guest_EIP); 975//.. 976//.. /* tell the tools */ 977//.. VG_TRACK( post_deliver_signal, tid, sigNo ); 978} 979 980#endif // defined(VGP_ppc32_linux) 981 982/*--------------------------------------------------------------------*/ 983/*--- end ---*/ 984/*--------------------------------------------------------------------*/ 985