/*--------------------------------------------------------------------*/
/*--- Create/destroy signal delivery frames. ---*/
/*--- sigframe-ppc32-linux.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Valgrind, a dynamic binary instrumentation
framework.
Copyright (C) 2000-2012 Nicholas Nethercote
njn@valgrind.org
Copyright (C) 2004-2012 Paul Mackerras
paulus@samba.org
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#if defined(VGP_ppc32_linux)
#include "pub_core_basics.h"
#include "pub_core_vki.h"
#include "pub_core_vkiscnums.h"
#include "pub_core_libcsetjmp.h" // to keep _threadstate.h happy
#include "pub_core_threadstate.h"
#include "pub_core_aspacemgr.h"
#include "pub_core_libcbase.h"
#include "pub_core_libcassert.h"
#include "pub_core_libcprint.h"
#include "pub_core_machine.h"
#include "pub_core_options.h"
#include "pub_core_sigframe.h"
#include "pub_core_signals.h"
#include "pub_core_tooliface.h"
#include "pub_core_trampoline.h"
#include "pub_core_transtab.h" // VG_(discard_translations)
/* This module creates and removes signal frames for signal deliveries
on ppc32-linux.
Note, this file contains kernel-specific knowledge in the form of
'struct sigframe' and 'struct rt_sigframe'. How does that relate
to the vki kernel interface stuff?
Either a 'struct sigframe' or a 'struct rtsigframe' is pushed
onto the client's stack. This contains a subsidiary
vki_ucontext. That holds the vcpu's state across the signal,
so that the sighandler can mess with the vcpu state if it
really wants.
FIXME: sigcontexting is basically broken for the moment. When
delivering a signal, the integer registers and %eflags are
correctly written into the sigcontext, however the FP and SSE state
is not. When returning from a signal, only the integer registers
are restored from the sigcontext; the rest of the CPU state is
restored to what it was before the signal.
This will be fixed.
*/
/*------------------------------------------------------------*/
/*--- Signal frame layouts ---*/
/*------------------------------------------------------------*/
// A structure in which to save the application's registers
// during the execution of signal handlers.
// Linux has 2 signal frame structures: one for normal signal
// deliveries, and one for SA_SIGINFO deliveries (also known as RT
// signals).
//
// In theory, so long as we get the arguments to the handler function
// right, it doesn't matter what the exact layout of the rest of the
// frame is. Unfortunately, things like gcc's exception unwinding
// make assumptions about the locations of various parts of the frame,
// so we need to duplicate it exactly.
/* Structure containing bits of information that we want to save
on signal delivery. */
struct vg_sig_private {
UInt magicPI;
UInt sigNo_private;
VexGuestPPC32State vex_shadow1;
VexGuestPPC32State vex_shadow2;
};
/* Structure put on stack for signal handlers with SA_SIGINFO clear. */
struct nonrt_sigframe {
UInt gap1[16];
struct vki_sigcontext sigcontext;
struct vki_mcontext mcontext;
struct vg_sig_private priv;
unsigned char abigap[224];
};
/* Structure put on stack for signal handlers with SA_SIGINFO set. */
struct rt_sigframe {
UInt gap1[20];
vki_siginfo_t siginfo;
struct vki_ucontext ucontext;
struct vg_sig_private priv;
unsigned char abigap[224];
};
#define SET_SIGNAL_LR(zztst, zzval) \
do { tst->arch.vex.guest_LR = (zzval); \
VG_TRACK( post_reg_write, Vg_CoreSignal, tst->tid, \
offsetof(VexGuestPPC32State,guest_LR), \
sizeof(UWord) ); \
} while (0)
#define SET_SIGNAL_GPR(zztst, zzn, zzval) \
do { tst->arch.vex.guest_GPR##zzn = (zzval); \
VG_TRACK( post_reg_write, Vg_CoreSignal, tst->tid, \
offsetof(VexGuestPPC32State,guest_GPR##zzn), \
sizeof(UWord) ); \
} while (0)
static
void stack_mcontext ( struct vki_mcontext *mc,
ThreadState* tst,
Bool use_rt_sigreturn,
UInt fault_addr )
{
VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "signal frame mcontext",
(Addr)mc, sizeof(struct vki_pt_regs) );
# define DO(gpr) mc->mc_gregs[VKI_PT_R0+gpr] = tst->arch.vex.guest_GPR##gpr
DO(0); DO(1); DO(2); DO(3); DO(4); DO(5); DO(6); DO(7);
DO(8); DO(9); DO(10); DO(11); DO(12); DO(13); DO(14); DO(15);
DO(16); DO(17); DO(18); DO(19); DO(20); DO(21); DO(22); DO(23);
DO(24); DO(25); DO(26); DO(27); DO(28); DO(29); DO(30); DO(31);
# undef DO
mc->mc_gregs[VKI_PT_NIP] = tst->arch.vex.guest_CIA;
mc->mc_gregs[VKI_PT_MSR] = 0xf032; /* pretty arbitrary */
mc->mc_gregs[VKI_PT_ORIG_R3] = tst->arch.vex.guest_GPR3;
mc->mc_gregs[VKI_PT_CTR] = tst->arch.vex.guest_CTR;
mc->mc_gregs[VKI_PT_LNK] = tst->arch.vex.guest_LR;
mc->mc_gregs[VKI_PT_XER] = LibVEX_GuestPPC32_get_XER(&tst->arch.vex);
mc->mc_gregs[VKI_PT_CCR] = LibVEX_GuestPPC32_get_CR(&tst->arch.vex);
mc->mc_gregs[VKI_PT_MQ] = 0;
mc->mc_gregs[VKI_PT_TRAP] = 0;
mc->mc_gregs[VKI_PT_DAR] = fault_addr;
mc->mc_gregs[VKI_PT_DSISR] = 0;
mc->mc_gregs[VKI_PT_RESULT] = 0;
VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid,
(Addr)mc, sizeof(struct vki_pt_regs) );
/* XXX should do FP and vector regs */
/* set up signal return trampoline */
/* NB. 5 Sept 07. mc->mc_pad[0..1] used to contain a the code to
which the signal handler returns, and it just did sys_sigreturn
or sys_rt_sigreturn. But this doesn't work if the stack is
non-executable, and it isn't consistent with the x86-linux and
amd64-linux scheme for removing the stack frame. So instead be
consistent and use a stub in m_trampoline. Then it doesn't
matter whether or not the (guest) stack is executable. This
fixes #149519 and #145837. */
VG_TRACK(pre_mem_write, Vg_CoreSignal, tst->tid, "signal frame mcontext",
(Addr)&mc->mc_pad, sizeof(mc->mc_pad));
mc->mc_pad[0] = 0; /* invalid */
mc->mc_pad[1] = 0; /* invalid */
VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid,
(Addr)&mc->mc_pad, sizeof(mc->mc_pad) );
/* invalidate any translation of this area */
VG_(discard_translations)( (Addr64)(Addr)&mc->mc_pad,
sizeof(mc->mc_pad), "stack_mcontext" );
/* set the signal handler to return to the trampoline */
SET_SIGNAL_LR(tst, (Addr)(use_rt_sigreturn
? (Addr)&VG_(ppc32_linux_SUBST_FOR_rt_sigreturn)
: (Addr)&VG_(ppc32_linux_SUBST_FOR_sigreturn)
));
}
//:: /* Valgrind-specific parts of the signal frame */
//:: struct vg_sigframe
//:: {
//:: /* Sanity check word. */
//:: UInt magicPI;
//::
//:: UInt handlerflags; /* flags for signal handler */
//::
//::
//:: /* Safely-saved version of sigNo, as described above. */
//:: Int sigNo_private;
//::
//:: /* XXX This is wrong. Surely we should store the shadow values
//:: into the shadow memory behind the actual values? */
//:: VexGuestPPC32State vex_shadow;
//::
//:: /* HACK ALERT */
//:: VexGuestPPC32State vex;
//:: /* end HACK ALERT */
//::
//:: /* saved signal mask to be restored when handler returns */
//:: vki_sigset_t mask;
//::
//:: /* Sanity check word. Is the highest-addressed word; do not
//:: move!*/
//:: UInt magicE;
//:: };
//::
//:: struct sigframe
//:: {
//:: /* Sig handler's return address */
//:: Addr retaddr;
//:: Int sigNo;
//::
//:: struct vki_sigcontext sigContext;
//:: //.. struct _vki_fpstate fpstate;
//::
//:: struct vg_sigframe vg;
//:: };
//::
//:: struct rt_sigframe
//:: {
//:: /* Sig handler's return address */
//:: Addr retaddr;
//:: Int sigNo;
//::
//:: /* ptr to siginfo_t. */
//:: Addr psigInfo;
//::
//:: /* ptr to ucontext */
//:: Addr puContext;
//:: /* pointed to by psigInfo */
//:: vki_siginfo_t sigInfo;
//::
//:: /* pointed to by puContext */
//:: struct vki_ucontext uContext;
//:: //.. struct _vki_fpstate fpstate;
//::
//:: struct vg_sigframe vg;
//:: };
//:: /*------------------------------------------------------------*/
//:: /*--- Signal operations ---*/
//:: /*------------------------------------------------------------*/
//::
//:: /*
//:: Great gobs of FP state conversion taken wholesale from
//:: linux/arch/i386/kernel/i387.c
//:: */
//::
//:: /*
//:: * FXSR floating point environment conversions.
//:: */
//:: #define X86_FXSR_MAGIC 0x0000
//::
//:: /*
//:: * FPU tag word conversions.
//:: */
//::
//:: static inline unsigned short twd_i387_to_fxsr( unsigned short twd )
//:: {
//:: unsigned int tmp; /* to avoid 16 bit prefixes in the code */
//::
//:: /* Transform each pair of bits into 01 (valid) or 00 (empty) */
//:: tmp = ~twd;
//:: tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
//:: /* and move the valid bits to the lower byte. */
//:: tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
//:: tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
//:: tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
//:: return tmp;
//:: }
//::
//:: static unsigned long twd_fxsr_to_i387( const struct i387_fxsave_struct *fxsave )
//:: {
//:: struct _vki_fpxreg *st = NULL;
//:: unsigned long twd = (unsigned long) fxsave->twd;
//:: unsigned long tag;
//:: unsigned long ret = 0xffff0000u;
//:: int i;
//::
//:: #define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16);
//::
//:: for ( i = 0 ; i < 8 ; i++ ) {
//:: if ( twd & 0x1 ) {
//:: st = (struct _vki_fpxreg *) FPREG_ADDR( fxsave, i );
//::
//:: switch ( st->exponent & 0x7fff ) {
//:: case 0x7fff:
//:: tag = 2; /* Special */
//:: break;
//:: case 0x0000:
//:: if ( !st->significand[0] &&
//:: !st->significand[1] &&
//:: !st->significand[2] &&
//:: !st->significand[3] ) {
//:: tag = 1; /* Zero */
//:: } else {
//:: tag = 2; /* Special */
//:: }
//:: break;
//:: default:
//:: if ( st->significand[3] & 0x8000 ) {
//:: tag = 0; /* Valid */
//:: } else {
//:: tag = 2; /* Special */
//:: }
//:: break;
//:: }
//:: } else {
//:: tag = 3; /* Empty */
//:: }
//:: ret |= (tag << (2 * i));
//:: twd = twd >> 1;
//:: }
//:: return ret;
//:: }
//::
//:: static void convert_fxsr_to_user( struct _vki_fpstate *buf,
//:: const struct i387_fxsave_struct *fxsave )
//:: {
//:: unsigned long env[7];
//:: struct _vki_fpreg *to;
//:: struct _vki_fpxreg *from;
//:: int i;
//::
//:: env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
//:: env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
//:: env[2] = twd_fxsr_to_i387(fxsave);
//:: env[3] = fxsave->fip;
//:: env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
//:: env[5] = fxsave->foo;
//:: env[6] = fxsave->fos;
//::
//:: VG_(memcpy)(buf, env, 7 * sizeof(unsigned long));
//::
//:: to = &buf->_st[0];
//:: from = (struct _vki_fpxreg *) &fxsave->st_space[0];
//:: for ( i = 0 ; i < 8 ; i++, to++, from++ ) {
//:: unsigned long __user *t = (unsigned long __user *)to;
//:: unsigned long *f = (unsigned long *)from;
//::
//:: t[0] = f[0];
//:: t[1] = f[1];
//:: to->exponent = from->exponent;
//:: }
//:: }
//::
//:: static void convert_fxsr_from_user( struct i387_fxsave_struct *fxsave,
//:: const struct _vki_fpstate *buf )
//:: {
//:: unsigned long env[7];
//:: struct _vki_fpxreg *to;
//:: const struct _vki_fpreg *from;
//:: int i;
//::
//:: VG_(memcpy)(env, buf, 7 * sizeof(long));
//::
//:: fxsave->cwd = (unsigned short)(env[0] & 0xffff);
//:: fxsave->swd = (unsigned short)(env[1] & 0xffff);
//:: fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
//:: fxsave->fip = env[3];
//:: fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
//:: fxsave->fcs = (env[4] & 0xffff);
//:: fxsave->foo = env[5];
//:: fxsave->fos = env[6];
//::
//:: to = (struct _vki_fpxreg *) &fxsave->st_space[0];
//:: from = &buf->_st[0];
//:: for ( i = 0 ; i < 8 ; i++, to++, from++ ) {
//:: unsigned long *t = (unsigned long *)to;
//:: unsigned long __user *f = (unsigned long __user *)from;
//::
//:: t[0] = f[0];
//:: t[1] = f[1];
//:: to->exponent = from->exponent;
//:: }
//:: }
//::
//:: static inline void save_i387_fsave( arch_thread_t *regs, struct _vki_fpstate *buf )
//:: {
//:: struct i387_fsave_struct *fs = ®s->m_sse.fsave;
//::
//:: fs->status = fs->swd;
//:: VG_(memcpy)(buf, fs, sizeof(*fs));
//:: }
//::
//:: static void save_i387_fxsave( arch_thread_t *regs, struct _vki_fpstate *buf )
//:: {
//:: const struct i387_fxsave_struct *fx = ®s->m_sse.fxsave;
//:: convert_fxsr_to_user( buf, fx );
//::
//:: buf->status = fx->swd;
//:: buf->magic = X86_FXSR_MAGIC;
//:: VG_(memcpy)(buf->_fxsr_env, fx, sizeof(struct i387_fxsave_struct));
//:: }
//::
//:: static void save_i387( arch_thread_t *regs, struct _vki_fpstate *buf )
//:: {
//:: if ( VG_(have_ssestate) )
//:: save_i387_fxsave( regs, buf );
//:: else
//:: save_i387_fsave( regs, buf );
//:: }
//::
//:: static inline void restore_i387_fsave( arch_thread_t *regs, const struct _vki_fpstate __user *buf )
//:: {
//:: VG_(memcpy)( ®s->m_sse.fsave, buf, sizeof(struct i387_fsave_struct) );
//:: }
//::
//:: static void restore_i387_fxsave( arch_thread_t *regs, const struct _vki_fpstate __user *buf )
//:: {
//:: VG_(memcpy)(®s->m_sse.fxsave, &buf->_fxsr_env[0],
//:: sizeof(struct i387_fxsave_struct) );
//:: /* mxcsr reserved bits must be masked to zero for security reasons */
//:: regs->m_sse.fxsave.mxcsr &= 0xffbf;
//:: convert_fxsr_from_user( ®s->m_sse.fxsave, buf );
//:: }
//::
//:: static void restore_i387( arch_thread_t *regs, const struct _vki_fpstate __user *buf )
//:: {
//:: if ( VG_(have_ssestate) ) {
//:: restore_i387_fxsave( regs, buf );
//:: } else {
//:: restore_i387_fsave( regs, buf );
//:: }
//:: }
/*------------------------------------------------------------*/
/*--- Creating signal frames ---*/
/*------------------------------------------------------------*/
//.. /* Create a plausible-looking sigcontext from the thread's
//.. Vex guest state. NOTE: does not fill in the FP or SSE
//.. bits of sigcontext at the moment.
//.. */
//.. static
//.. void synth_ucontext(ThreadId tid, const vki_siginfo_t *si,
//.. const vki_sigset_t *set, struct vki_ucontext *uc)
//.. {
//.. ThreadState *tst = VG_(get_ThreadState)(tid);
//.. struct vki_sigcontext *sc = &uc->uc_mcontext;
//..
//.. VG_(memset)(uc, 0, sizeof(*uc));
//..
//.. uc->uc_flags = 0;
//.. uc->uc_link = 0;
//.. uc->uc_sigmask = *set;
//.. uc->uc_stack = tst->altstack;
//.. sc->fpstate = fpstate;
//..
//.. // FIXME: save_i387(&tst->arch, fpstate);
//..
//.. # define SC2(reg,REG) sc->reg = tst->arch.vex.guest_##REG
//.. SC2(gs,GS);
//.. SC2(fs,FS);
//.. SC2(es,ES);
//.. SC2(ds,DS);
//..
//.. SC2(edi,EDI);
//.. SC2(esi,ESI);
//.. SC2(ebp,EBP);
//.. SC2(esp,ESP);
//.. SC2(ebx,EBX);
//.. SC2(edx,EDX);
//.. SC2(ecx,ECX);
//.. SC2(eax,EAX);
//..
//.. SC2(eip,EIP);
//.. SC2(cs,CS);
//.. sc->eflags = LibVEX_GuestX86_get_eflags(&tst->arch.vex);
//.. SC2(ss,SS);
//.. /* XXX esp_at_signal */
//.. /* XXX trapno */
//.. /* XXX err */
//.. # undef SC2
//..
//.. sc->cr2 = (UInt)si->_sifields._sigfault._addr;
//.. }
/*
//.. #define SET_SIGNAL_ESP(zztid, zzval) \
//.. SET_THREAD_REG(zztid, zzval, STACK_PTR, post_reg_write, \
//.. Vg_CoreSignal, zztid, VG_O_STACK_PTR, sizeof(Addr))
*/
/* Extend the stack segment downwards if needed so as to ensure the
new signal frames are mapped to something. Return a Bool
indicating whether or not the operation was successful.
*/
static Bool extend ( ThreadState *tst, Addr addr, SizeT size )
{
ThreadId tid = tst->tid;
NSegment const* stackseg = NULL;
if (VG_(extend_stack)(addr, tst->client_stack_szB)) {
stackseg = VG_(am_find_nsegment)(addr);
if (0 && stackseg)
VG_(printf)("frame=%#lx seg=%#lx-%#lx\n",
addr, stackseg->start, stackseg->end);
}
if (stackseg == NULL || !stackseg->hasR || !stackseg->hasW) {
VG_(message)(
Vg_UserMsg,
"Can't extend stack to %#lx during signal delivery for thread %d:\n",
addr, tid);
if (stackseg == NULL)
VG_(message)(Vg_UserMsg, " no stack segment\n");
else
VG_(message)(Vg_UserMsg, " too small or bad protection modes\n");
/* set SIGSEGV to default handler */
VG_(set_default_handler)(VKI_SIGSEGV);
VG_(synth_fault_mapping)(tid, addr);
/* The whole process should be about to die, since the default
action of SIGSEGV to kill the whole process. */
return False;
}
/* For tracking memory events, indicate the entire frame has been
allocated. */
VG_TRACK( new_mem_stack_signal, addr - VG_STACK_REDZONE_SZB,
size + VG_STACK_REDZONE_SZB, tid );
return True;
}
//.. /* Build the Valgrind-specific part of a signal frame. */
//..
//.. static void build_vg_sigframe(struct vg_sigframe *frame,
//.. ThreadState *tst,
//.. const vki_sigset_t *mask,
//.. UInt flags,
//.. Int sigNo)
//.. {
//.. frame->sigNo_private = sigNo;
//.. frame->magicPI = 0x31415927;
//.. frame->vex_shadow = tst->arch.vex_shadow;
//.. /* HACK ALERT */
//.. frame->vex = tst->arch.vex;
//.. /* end HACK ALERT */
//.. frame->mask = tst->sig_mask;
//.. frame->handlerflags = flags;
//.. frame->magicE = 0x27182818;
//.. }
//.. static Addr build_sigframe(ThreadState *tst,
//.. Addr esp_top_of_frame,
//.. const vki_siginfo_t *siginfo,
//.. void *handler, UInt flags,
//.. const vki_sigset_t *mask,
//.. void *restorer)
//.. {
//.. struct sigframe *frame;
//.. Addr esp = esp_top_of_frame;
//.. Int sigNo = siginfo->si_signo;
//.. struct vki_ucontext uc;
//..
//.. vg_assert((flags & VKI_SA_SIGINFO) == 0);
//..
//.. esp -= sizeof(*frame);
//.. esp = ROUNDDN(esp, 16);
//.. frame = (struct sigframe *)esp;
//..
//.. if (!extend(tst, esp, sizeof(*frame)))
//.. return esp_top_of_frame;
//..
//.. /* retaddr, sigNo, siguContext fields are to be written */
//.. VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "signal handler frame",
//.. esp, offsetof(struct sigframe, vg) );
//..
//.. frame->sigNo = sigNo;
//..
//.. if (flags & VKI_SA_RESTORER)
//.. frame->retaddr = (Addr)restorer;
//.. else
//.. frame->retaddr
//.. = VG_(client_trampoline_code)+VG_(tramp_sigreturn_offset);
//..
//.. synth_ucontext(tst->tid, siginfo, mask, &uc, &frame->fpstate);
//..
//.. VG_(memcpy)(&frame->sigContext, &uc.uc_mcontext,
//.. sizeof(struct vki_sigcontext));
//.. frame->sigContext.oldmask = mask->sig[0];
//..
//.. VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid,
//.. esp, offsetof(struct sigframe, vg) );
//..
//.. build_vg_sigframe(&frame->vg, tst, mask, flags, sigNo);
//..
//.. return esp;
//.. }
//.. static Addr build_rt_sigframe(ThreadState *tst,
//.. Addr esp_top_of_frame,
//.. const vki_siginfo_t *siginfo,
//.. void *handler, UInt flags,
//.. const vki_sigset_t *mask,
//.. void *restorer)
//.. {
//.. struct rt_sigframe *frame;
//.. Addr esp = esp_top_of_frame;
//.. Int sigNo = siginfo->si_signo;
//..
//.. vg_assert((flags & VKI_SA_SIGINFO) != 0);
//..
//.. esp -= sizeof(*frame);
//.. esp = ROUNDDN(esp, 16);
//.. frame = (struct rt_sigframe *)esp;
//..
//.. if (!extend(tst, esp, sizeof(*frame)))
//.. return esp_top_of_frame;
//..
//.. /* retaddr, sigNo, pSiginfo, puContext fields are to be written */
//.. VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "rt signal handler frame",
//.. esp, offsetof(struct rt_sigframe, vg) );
//..
//.. frame->sigNo = sigNo;
//..
//.. if (flags & VKI_SA_RESTORER)
//.. frame->retaddr = (Addr)restorer;
//.. else
//.. frame->retaddr
//.. = VG_(client_trampoline_code)+VG_(tramp_rt_sigreturn_offset);
//..
//.. frame->psigInfo = (Addr)&frame->sigInfo;
//.. frame->puContext = (Addr)&frame->uContext;
//.. VG_(memcpy)(&frame->sigInfo, siginfo, sizeof(vki_siginfo_t));
//..
//.. /* SIGILL defines addr to be the faulting address */
//.. if (sigNo == VKI_SIGILL && siginfo->si_code > 0)
//.. frame->sigInfo._sifields._sigfault._addr
//.. = (void*)tst->arch.vex.guest_CIA;
//..
//.. synth_ucontext(tst->tid, siginfo, mask, &frame->uContext, &frame->fpstate);
//..
//.. VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid,
//.. esp, offsetof(struct rt_sigframe, vg) );
//..
//.. build_vg_sigframe(&frame->vg, tst, mask, flags, sigNo);
//..
//.. return esp;
//.. }
/* EXPORTED */
void VG_(sigframe_create)( ThreadId tid,
Addr sp_top_of_frame,
const vki_siginfo_t *siginfo,
const struct vki_ucontext *siguc,
void *handler,
UInt flags,
const vki_sigset_t *mask,
void *restorer )
{
struct vg_sig_private *priv;
Addr sp;
ThreadState *tst;
Int sigNo = siginfo->si_signo;
Addr faultaddr;
/* Stack must be 16-byte aligned */
sp_top_of_frame &= ~0xf;
if (flags & VKI_SA_SIGINFO) {
sp = sp_top_of_frame - sizeof(struct rt_sigframe);
} else {
sp = sp_top_of_frame - sizeof(struct nonrt_sigframe);
}
tst = VG_(get_ThreadState)(tid);
if (!extend(tst, sp, sp_top_of_frame - sp))
return;
vg_assert(VG_IS_16_ALIGNED(sp));
/* Set up the stack chain pointer */
VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal handler frame",
sp, sizeof(UWord) );
*(Addr *)sp = tst->arch.vex.guest_GPR1;
VG_TRACK( post_mem_write, Vg_CoreSignal, tid,
sp, sizeof(UWord) );
faultaddr = (Addr)siginfo->_sifields._sigfault._addr;
if (sigNo == VKI_SIGILL && siginfo->si_code > 0)
faultaddr = tst->arch.vex.guest_CIA;
if (flags & VKI_SA_SIGINFO) {
struct rt_sigframe *frame = (struct rt_sigframe *) sp;
struct vki_ucontext *ucp = &frame->ucontext;
VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame siginfo",
(Addr)&frame->siginfo, sizeof(frame->siginfo) );
VG_(memcpy)(&frame->siginfo, siginfo, sizeof(*siginfo));
VG_TRACK( post_mem_write, Vg_CoreSignal, tid,
(Addr)&frame->siginfo, sizeof(frame->siginfo) );
VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame ucontext",
(Addr)ucp, offsetof(struct vki_ucontext, uc_pad) );
ucp->uc_flags = 0;
ucp->uc_link = 0;
ucp->uc_stack = tst->altstack;
VG_TRACK( post_mem_write, Vg_CoreSignal, tid, (Addr)ucp,
offsetof(struct vki_ucontext, uc_pad) );
VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame ucontext",
(Addr)&ucp->uc_regs,
sizeof(ucp->uc_regs) + sizeof(ucp->uc_sigmask) );
ucp->uc_regs = &ucp->uc_mcontext;
ucp->uc_sigmask = tst->sig_mask;
VG_TRACK( post_mem_write, Vg_CoreSignal, tid,
(Addr)&ucp->uc_regs,
sizeof(ucp->uc_regs) + sizeof(ucp->uc_sigmask) );
stack_mcontext(&ucp->uc_mcontext, tst, True/*use_rt_sigreturn*/, faultaddr);
priv = &frame->priv;
SET_SIGNAL_GPR(tid, 4, (Addr) &frame->siginfo);
SET_SIGNAL_GPR(tid, 5, (Addr) ucp);
/* the kernel sets this, though it doesn't seem to be in the ABI */
SET_SIGNAL_GPR(tid, 6, (Addr) &frame->siginfo);
} else {
/* non-RT signal delivery */
struct nonrt_sigframe *frame = (struct nonrt_sigframe *) sp;
struct vki_sigcontext *scp = &frame->sigcontext;
VG_TRACK( pre_mem_write, Vg_CoreSignal, tid, "signal frame sigcontext",
(Addr)&scp->_unused[3], sizeof(*scp) - 3 * sizeof(UInt) );
scp->signal = sigNo;
scp->handler = (Addr) handler;
scp->oldmask = tst->sig_mask.sig[0];
scp->_unused[3] = tst->sig_mask.sig[1];
VG_TRACK( post_mem_write, Vg_CoreSignal, tid,
(Addr)&scp->_unused[3], sizeof(*scp) - 3 * sizeof(UInt) );
stack_mcontext(&frame->mcontext, tst, False/*!use_rt_sigreturn*/, faultaddr);
priv = &frame->priv;
SET_SIGNAL_GPR(tid, 4, (Addr) scp);
}
priv->magicPI = 0x31415927;
priv->sigNo_private = sigNo;
priv->vex_shadow1 = tst->arch.vex_shadow1;
priv->vex_shadow2 = tst->arch.vex_shadow2;
SET_SIGNAL_GPR(tid, 1, sp);
SET_SIGNAL_GPR(tid, 3, sigNo);
tst->arch.vex.guest_CIA = (Addr) handler;
//.. Addr esp;
//.. ThreadState* tst = VG_(get_ThreadState)(tid);
//..
//.. if (flags & VKI_SA_SIGINFO)
//.. esp = build_rt_sigframe(tst, esp_top_of_frame, siginfo,
//.. handler, flags, mask, restorer);
//.. else
//.. esp = build_sigframe(tst, esp_top_of_frame,
//.. siginfo, handler, flags, mask, restorer);
//..
//.. /* Set the thread so it will next run the handler. */
//.. /* tst->m_esp = esp; */
//.. SET_SIGNAL_ESP(tid, esp);
//..
//.. //VG_(printf)("handler = %p\n", handler);
//.. tst->arch.vex.guest_CIA = (Addr) handler;
//.. /* This thread needs to be marked runnable, but we leave that the
//.. caller to do. */
if (0)
VG_(printf)("pushed signal frame; %%R1 now = %#lx, "
"next %%CIA = %#x, status=%d\n",
sp, tst->arch.vex.guest_CIA, tst->status);
}
/*------------------------------------------------------------*/
/*--- Destroying signal frames ---*/
/*------------------------------------------------------------*/
//.. /* Return False and don't do anything, just set the client to take a
//.. segfault, if it looks like the frame is corrupted. */
//.. static
//.. Bool restore_vg_sigframe ( ThreadState *tst,
//.. struct vg_sigframe *frame, Int *sigNo )
//.. {
//.. if (frame->magicPI != 0x31415927 ||
//.. frame->magicE != 0x27182818) {
//.. VG_(message)(Vg_UserMsg, "Thread %d return signal frame "
//.. "corrupted. Killing process.",
//.. tst->tid);
//.. VG_(set_default_handler)(VKI_SIGSEGV);
//.. VG_(synth_fault)(tst->tid);
//.. *sigNo = VKI_SIGSEGV;
//.. return False;
//.. }
//.. tst->sig_mask = frame->mask;
//.. tst->tmp_sig_mask = frame->mask;
//.. tst->arch.vex_shadow = frame->vex_shadow;
//.. /* HACK ALERT */
//.. tst->arch.vex = frame->vex;
//.. /* end HACK ALERT */
//.. *sigNo = frame->sigNo_private;
//.. return True;
//.. }
//.. static
//.. void restore_sigcontext( ThreadState *tst,
//.. struct vki_sigcontext *sc )
//.. //.. struct vki_sigcontext *sc, struct _vki_fpstate *fpstate )
//.. {
//.. tst->arch.vex.guest_EAX = sc->eax;
//.. tst->arch.vex.guest_ECX = sc->ecx;
//.. tst->arch.vex.guest_EDX = sc->edx;
//.. tst->arch.vex.guest_EBX = sc->ebx;
//.. tst->arch.vex.guest_EBP = sc->ebp;
//.. tst->arch.vex.guest_ESP = sc->esp;
//.. tst->arch.vex.guest_ESI = sc->esi;
//.. tst->arch.vex.guest_EDI = sc->edi;
//.. //:: tst->arch.vex.guest_eflags = sc->eflags;
//.. //:: tst->arch.vex.guest_EIP = sc->eip;
//..
//.. tst->arch.vex.guest_CS = sc->cs;
//.. tst->arch.vex.guest_SS = sc->ss;
//.. tst->arch.vex.guest_DS = sc->ds;
//.. tst->arch.vex.guest_ES = sc->es;
//.. tst->arch.vex.guest_FS = sc->fs;
//.. tst->arch.vex.guest_GS = sc->gs;
//..
//.. //:: restore_i387(&tst->arch, fpstate);
//.. }
//.. static
//.. SizeT restore_sigframe ( ThreadState *tst,
//.. struct sigframe *frame, Int *sigNo )
//.. {
//.. if (restore_vg_sigframe(tst, &frame->vg, sigNo))
//.. restore_sigcontext(tst, &frame->sigContext, &frame->fpstate);
//.. return sizeof(*frame);
//.. }
//.. static
//.. SizeT restore_rt_sigframe ( ThreadState *tst,
//.. struct rt_sigframe *frame, Int *sigNo )
//.. {
//.. if (restore_vg_sigframe(tst, &frame->vg, sigNo))
//.. restore_sigcontext(tst, &frame->uContext.uc_mcontext, &frame->fpstate);
//.. return sizeof(*frame);
//.. }
/* EXPORTED */
void VG_(sigframe_destroy)( ThreadId tid, Bool isRT )
{
ThreadState *tst;
struct vg_sig_private *priv;
Addr sp;
UInt frame_size;
struct vki_mcontext *mc;
Int sigNo;
Bool has_siginfo = isRT;
vg_assert(VG_(is_valid_tid)(tid));
tst = VG_(get_ThreadState)(tid);
/* Check that the stack frame looks valid */
sp = tst->arch.vex.guest_GPR1;
vg_assert(VG_IS_16_ALIGNED(sp));
/* JRS 17 Nov 05: This code used to check that *sp -- which should
have been set by the stwu at the start of the handler -- points
to just above the frame (ie, the previous frame). However, that
isn't valid when delivering signals on alt stacks. So I removed
it. The frame is still sanity-checked using the priv->magicPI
field. */
if (has_siginfo) {
struct rt_sigframe *frame = (struct rt_sigframe *)sp;
frame_size = sizeof(*frame);
mc = &frame->ucontext.uc_mcontext;
priv = &frame->priv;
vg_assert(priv->magicPI == 0x31415927);
tst->sig_mask = frame->ucontext.uc_sigmask;
} else {
struct nonrt_sigframe *frame = (struct nonrt_sigframe *)sp;
frame_size = sizeof(*frame);
mc = &frame->mcontext;
priv = &frame->priv;
vg_assert(priv->magicPI == 0x31415927);
tst->sig_mask.sig[0] = frame->sigcontext.oldmask;
tst->sig_mask.sig[1] = frame->sigcontext._unused[3];
}
tst->tmp_sig_mask = tst->sig_mask;
sigNo = priv->sigNo_private;
# define DO(gpr) tst->arch.vex.guest_GPR##gpr = mc->mc_gregs[VKI_PT_R0+gpr]
DO(0); DO(1); DO(2); DO(3); DO(4); DO(5); DO(6); DO(7);
DO(8); DO(9); DO(10); DO(11); DO(12); DO(13); DO(14); DO(15);
DO(16); DO(17); DO(18); DO(19); DO(20); DO(21); DO(22); DO(23);
DO(24); DO(25); DO(26); DO(27); DO(28); DO(29); DO(30); DO(31);
# undef DO
tst->arch.vex.guest_CIA = mc->mc_gregs[VKI_PT_NIP];
// Umm ... ? (jrs 2005 July 8)
// tst->arch.m_orig_gpr3 = mc->mc_gregs[VKI_PT_ORIG_R3];
LibVEX_GuestPPC32_put_CR( mc->mc_gregs[VKI_PT_CCR], &tst->arch.vex );
tst->arch.vex.guest_LR = mc->mc_gregs[VKI_PT_LNK];
tst->arch.vex.guest_CTR = mc->mc_gregs[VKI_PT_CTR];
LibVEX_GuestPPC32_put_XER( mc->mc_gregs[VKI_PT_XER], &tst->arch.vex );
tst->arch.vex_shadow1 = priv->vex_shadow1;
tst->arch.vex_shadow2 = priv->vex_shadow2;
VG_TRACK(die_mem_stack_signal, sp, frame_size);
if (VG_(clo_trace_signals))
VG_(message)(Vg_DebugMsg,
"vg_pop_signal_frame (thread %d): "
"isRT=%d valid magic; EIP=%#x\n",
tid, has_siginfo, tst->arch.vex.guest_CIA);
/* tell the tools */
VG_TRACK( post_deliver_signal, tid, sigNo );
//.. Addr esp;
//.. ThreadState* tst;
//.. SizeT size;
//.. Int sigNo;
//..
//.. tst = VG_(get_ThreadState)(tid);
//..
//.. /* Correctly reestablish the frame base address. */
//.. esp = tst->arch.vex.guest_ESP;
//..
//.. if (!isRT)
//.. size = restore_sigframe(tst, (struct sigframe *)esp, &sigNo);
//.. else
//.. size = restore_rt_sigframe(tst, (struct rt_sigframe *)esp, &sigNo);
//..
//.. VG_TRACK( die_mem_stack_signal, esp, size );
//..
//.. if (VG_(clo_trace_signals))
//.. VG_(message)(
//.. Vg_DebugMsg,
//.. "VG_(signal_return) (thread %d): isRT=%d valid magic; EIP=%p",
//.. tid, isRT, tst->arch.vex.guest_EIP);
//..
//.. /* tell the tools */
//.. VG_TRACK( post_deliver_signal, tid, sigNo );
}
#endif // defined(VGP_ppc32_linux)
/*--------------------------------------------------------------------*/
/*--- end ---*/
/*--------------------------------------------------------------------*/