/*--------------------------------------------------------------------*/
/*--- Create/destroy signal delivery frames. ---*/
/*--- sigframe-s390x-linux.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Valgrind, a dynamic binary instrumentation
framework.
Copyright IBM Corp. 2010-2013
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.
*/
/* Contributed by Christian Borntraeger */
#include "pub_core_basics.h"
#include "pub_core_vki.h"
#include "pub_core_vkiscnums.h"
#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 "priv_sigframe.h"
#if defined(VGA_s390x)
/* This module creates and removes signal frames for signal deliveries
on s390x-linux.
Note, this file contains kernel-specific knowledge in the form of
'struct sigframe' and 'struct rt_sigframe'.
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.
*/
#define SET_SIGNAL_GPR(zztst, zzn, zzval) \
do { zztst->arch.vex.guest_r##zzn = (unsigned long)(zzval); \
VG_TRACK( post_reg_write, Vg_CoreSignal, zztst->tid, \
offsetof(VexGuestS390XState,guest_r##zzn), \
sizeof(UWord) ); \
} while (0)
/*------------------------------------------------------------*/
/*--- 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.
/* 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? */
VexGuestS390XState vex_shadow1;
VexGuestS390XState vex_shadow2;
/* HACK ALERT */
VexGuestS390XState 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;
};
#define S390_SYSCALL_SIZE 2
struct sigframe
{
UChar callee_used_stack[__VKI_SIGNAL_FRAMESIZE];
struct vki_sigcontext sc;
_vki_sigregs sregs;
Int sigNo;
UChar retcode[S390_SYSCALL_SIZE];
struct vg_sigframe vg;
};
struct rt_sigframe
{
UChar callee_used_stack[__VKI_SIGNAL_FRAMESIZE];
UChar retcode[S390_SYSCALL_SIZE];
struct vki_siginfo info;
struct vki_ucontext uc;
struct vg_sigframe vg;
};
/*------------------------------------------------------------*/
/*--- Creating signal frames ---*/
/*------------------------------------------------------------*/
/* Saves all user-controlled register into a _vki_sigregs structure */
static void save_sigregs(ThreadState *tst, _vki_sigregs *sigregs)
{
sigregs->regs.gprs[0] = tst->arch.vex.guest_r0;
sigregs->regs.gprs[1] = tst->arch.vex.guest_r1;
sigregs->regs.gprs[2] = tst->arch.vex.guest_r2;
sigregs->regs.gprs[3] = tst->arch.vex.guest_r3;
sigregs->regs.gprs[4] = tst->arch.vex.guest_r4;
sigregs->regs.gprs[5] = tst->arch.vex.guest_r5;
sigregs->regs.gprs[6] = tst->arch.vex.guest_r6;
sigregs->regs.gprs[7] = tst->arch.vex.guest_r7;
sigregs->regs.gprs[8] = tst->arch.vex.guest_r8;
sigregs->regs.gprs[9] = tst->arch.vex.guest_r9;
sigregs->regs.gprs[10] = tst->arch.vex.guest_r10;
sigregs->regs.gprs[11] = tst->arch.vex.guest_r11;
sigregs->regs.gprs[12] = tst->arch.vex.guest_r12;
sigregs->regs.gprs[13] = tst->arch.vex.guest_r13;
sigregs->regs.gprs[14] = tst->arch.vex.guest_r14;
sigregs->regs.gprs[15] = tst->arch.vex.guest_r15;
sigregs->regs.acrs[0] = tst->arch.vex.guest_a0;
sigregs->regs.acrs[1] = tst->arch.vex.guest_a1;
sigregs->regs.acrs[2] = tst->arch.vex.guest_a2;
sigregs->regs.acrs[3] = tst->arch.vex.guest_a3;
sigregs->regs.acrs[4] = tst->arch.vex.guest_a4;
sigregs->regs.acrs[5] = tst->arch.vex.guest_a5;
sigregs->regs.acrs[6] = tst->arch.vex.guest_a6;
sigregs->regs.acrs[7] = tst->arch.vex.guest_a7;
sigregs->regs.acrs[8] = tst->arch.vex.guest_a8;
sigregs->regs.acrs[9] = tst->arch.vex.guest_a9;
sigregs->regs.acrs[10] = tst->arch.vex.guest_a10;
sigregs->regs.acrs[11] = tst->arch.vex.guest_a11;
sigregs->regs.acrs[12] = tst->arch.vex.guest_a12;
sigregs->regs.acrs[13] = tst->arch.vex.guest_a13;
sigregs->regs.acrs[14] = tst->arch.vex.guest_a14;
sigregs->regs.acrs[15] = tst->arch.vex.guest_a15;
sigregs->fpregs.fprs[0] = tst->arch.vex.guest_f0;
sigregs->fpregs.fprs[1] = tst->arch.vex.guest_f1;
sigregs->fpregs.fprs[2] = tst->arch.vex.guest_f2;
sigregs->fpregs.fprs[3] = tst->arch.vex.guest_f3;
sigregs->fpregs.fprs[4] = tst->arch.vex.guest_f4;
sigregs->fpregs.fprs[5] = tst->arch.vex.guest_f5;
sigregs->fpregs.fprs[6] = tst->arch.vex.guest_f6;
sigregs->fpregs.fprs[7] = tst->arch.vex.guest_f7;
sigregs->fpregs.fprs[8] = tst->arch.vex.guest_f8;
sigregs->fpregs.fprs[9] = tst->arch.vex.guest_f9;
sigregs->fpregs.fprs[10] = tst->arch.vex.guest_f10;
sigregs->fpregs.fprs[11] = tst->arch.vex.guest_f11;
sigregs->fpregs.fprs[12] = tst->arch.vex.guest_f12;
sigregs->fpregs.fprs[13] = tst->arch.vex.guest_f13;
sigregs->fpregs.fprs[14] = tst->arch.vex.guest_f14;
sigregs->fpregs.fprs[15] = tst->arch.vex.guest_f15;
sigregs->fpregs.fpc = tst->arch.vex.guest_fpc;
sigregs->regs.psw.addr = tst->arch.vex.guest_IA;
/* save a sane dummy mask */
sigregs->regs.psw.mask = 0x0705000180000000UL;
}
static void restore_sigregs(ThreadState *tst, _vki_sigregs *sigregs)
{
tst->arch.vex.guest_r0 = sigregs->regs.gprs[0];
tst->arch.vex.guest_r1 = sigregs->regs.gprs[1];
tst->arch.vex.guest_r2 = sigregs->regs.gprs[2];
tst->arch.vex.guest_r3 = sigregs->regs.gprs[3];
tst->arch.vex.guest_r4 = sigregs->regs.gprs[4];
tst->arch.vex.guest_r5 = sigregs->regs.gprs[5];
tst->arch.vex.guest_r6 = sigregs->regs.gprs[6];
tst->arch.vex.guest_r7 = sigregs->regs.gprs[7];
tst->arch.vex.guest_r8 = sigregs->regs.gprs[8];
tst->arch.vex.guest_r9 = sigregs->regs.gprs[9];
tst->arch.vex.guest_r10 = sigregs->regs.gprs[10];
tst->arch.vex.guest_r11 = sigregs->regs.gprs[11];
tst->arch.vex.guest_r12 = sigregs->regs.gprs[12];
tst->arch.vex.guest_r13 = sigregs->regs.gprs[13];
tst->arch.vex.guest_r14 = sigregs->regs.gprs[14];
tst->arch.vex.guest_r15 = sigregs->regs.gprs[15];
tst->arch.vex.guest_a0 = sigregs->regs.acrs[0];
tst->arch.vex.guest_a1 = sigregs->regs.acrs[1];
tst->arch.vex.guest_a2 = sigregs->regs.acrs[2];
tst->arch.vex.guest_a3 = sigregs->regs.acrs[3];
tst->arch.vex.guest_a4 = sigregs->regs.acrs[4];
tst->arch.vex.guest_a5 = sigregs->regs.acrs[5];
tst->arch.vex.guest_a6 = sigregs->regs.acrs[6];
tst->arch.vex.guest_a7 = sigregs->regs.acrs[7];
tst->arch.vex.guest_a8 = sigregs->regs.acrs[8];
tst->arch.vex.guest_a9 = sigregs->regs.acrs[9];
tst->arch.vex.guest_a10 = sigregs->regs.acrs[10];
tst->arch.vex.guest_a11 = sigregs->regs.acrs[11];
tst->arch.vex.guest_a12 = sigregs->regs.acrs[12];
tst->arch.vex.guest_a13 = sigregs->regs.acrs[13];
tst->arch.vex.guest_a14 = sigregs->regs.acrs[14];
tst->arch.vex.guest_a15 = sigregs->regs.acrs[15];
tst->arch.vex.guest_f0 = sigregs->fpregs.fprs[0];
tst->arch.vex.guest_f1 = sigregs->fpregs.fprs[1];
tst->arch.vex.guest_f2 = sigregs->fpregs.fprs[2];
tst->arch.vex.guest_f3 = sigregs->fpregs.fprs[3];
tst->arch.vex.guest_f4 = sigregs->fpregs.fprs[4];
tst->arch.vex.guest_f5 = sigregs->fpregs.fprs[5];
tst->arch.vex.guest_f6 = sigregs->fpregs.fprs[6];
tst->arch.vex.guest_f7 = sigregs->fpregs.fprs[7];
tst->arch.vex.guest_f8 = sigregs->fpregs.fprs[8];
tst->arch.vex.guest_f9 = sigregs->fpregs.fprs[9];
tst->arch.vex.guest_f10 = sigregs->fpregs.fprs[10];
tst->arch.vex.guest_f11 = sigregs->fpregs.fprs[11];
tst->arch.vex.guest_f12 = sigregs->fpregs.fprs[12];
tst->arch.vex.guest_f13 = sigregs->fpregs.fprs[13];
tst->arch.vex.guest_f14 = sigregs->fpregs.fprs[14];
tst->arch.vex.guest_f15 = sigregs->fpregs.fprs[15];
tst->arch.vex.guest_fpc = sigregs->fpregs.fpc;
tst->arch.vex.guest_IA = sigregs->regs.psw.addr;
}
/* Build the Valgrind-specific part of a signal frame. */
static void build_vg_sigframe(struct vg_sigframe *frame,
ThreadState *tst,
UInt flags,
Int sigNo)
{
frame->sigNo_private = sigNo;
frame->magicPI = 0x31415927;
frame->vex_shadow1 = tst->arch.vex_shadow1;
frame->vex_shadow2 = tst->arch.vex_shadow2;
/* 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 sp_top_of_frame,
const vki_siginfo_t *siginfo,
const struct vki_ucontext *siguc,
UInt flags,
const vki_sigset_t *mask,
void *restorer)
{
struct sigframe *frame;
Addr sp = sp_top_of_frame;
vg_assert((flags & VKI_SA_SIGINFO) == 0);
vg_assert((sizeof(*frame) & 7) == 0);
vg_assert((sp & 7) == 0);
sp -= sizeof(*frame);
frame = (struct sigframe *)sp;
if (! ML_(sf_maybe_extend_stack)(tst, sp, sizeof(*frame), flags))
return sp_top_of_frame;
/* retcode, sigNo, sc, sregs fields are to be written */
VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "signal handler frame",
sp, offsetof(struct sigframe, vg) );
save_sigregs(tst, &frame->sregs);
frame->sigNo = siginfo->si_signo;
frame->sc.sregs = &frame->sregs;
VG_(memcpy)(frame->sc.oldmask, mask->sig, sizeof(frame->sc.oldmask));
if (flags & VKI_SA_RESTORER) {
SET_SIGNAL_GPR(tst, 14, restorer);
} else {
frame->retcode[0] = 0x0a;
frame->retcode[1] = __NR_sigreturn;
/* This normally should be &frame->recode. but since there
might be problems with non-exec stack and we must discard
the translation for the on-stack sigreturn we just use the
trampoline like x86,ppc. We still fill in the retcode, lets
just hope that nobody actually jumps here */
SET_SIGNAL_GPR(tst, 14, (Addr)&VG_(s390x_linux_SUBST_FOR_sigreturn));
}
SET_SIGNAL_GPR(tst, 2, siginfo->si_signo);
SET_SIGNAL_GPR(tst, 3, &frame->sc);
/* fixs390: we dont fill in trapno and prot_addr in r4 and r5*/
/* Set up backchain. */
*((Addr *) sp) = sp_top_of_frame;
VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid,
sp, offsetof(struct sigframe, vg) );
build_vg_sigframe(&frame->vg, tst, flags, siginfo->si_signo);
return sp;
}
static Addr build_rt_sigframe(ThreadState *tst,
Addr sp_top_of_frame,
const vki_siginfo_t *siginfo,
const struct vki_ucontext *siguc,
UInt flags,
const vki_sigset_t *mask,
void *restorer)
{
struct rt_sigframe *frame;
Addr sp = sp_top_of_frame;
Int sigNo = siginfo->si_signo;
vg_assert((flags & VKI_SA_SIGINFO) != 0);
vg_assert((sizeof(*frame) & 7) == 0);
vg_assert((sp & 7) == 0);
sp -= sizeof(*frame);
frame = (struct rt_sigframe *)sp;
if (! ML_(sf_maybe_extend_stack)(tst, sp, sizeof(*frame), flags))
return sp_top_of_frame;
/* retcode, sigNo, sc, sregs fields are to be written */
VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "signal handler frame",
sp, offsetof(struct rt_sigframe, vg) );
save_sigregs(tst, &frame->uc.uc_mcontext);
if (flags & VKI_SA_RESTORER) {
frame->retcode[0] = 0;
frame->retcode[1] = 0;
SET_SIGNAL_GPR(tst, 14, restorer);
} else {
frame->retcode[0] = 0x0a;
frame->retcode[1] = __NR_rt_sigreturn;
/* This normally should be &frame->recode. but since there
might be problems with non-exec stack and we must discard
the translation for the on-stack sigreturn we just use the
trampoline like x86,ppc. We still fill in the retcode, lets
just hope that nobody actually jumps here */
SET_SIGNAL_GPR(tst, 14, (Addr)&VG_(s390x_linux_SUBST_FOR_rt_sigreturn));
}
VG_(memcpy)(&frame->info, siginfo, sizeof(vki_siginfo_t));
frame->uc.uc_flags = 0;
frame->uc.uc_link = 0;
frame->uc.uc_sigmask = *mask;
frame->uc.uc_stack = tst->altstack;
SET_SIGNAL_GPR(tst, 2, siginfo->si_signo);
SET_SIGNAL_GPR(tst, 3, &frame->info);
SET_SIGNAL_GPR(tst, 4, &frame->uc);
/* Set up backchain. */
*((Addr *) sp) = sp_top_of_frame;
VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid,
sp, offsetof(struct rt_sigframe, vg) );
build_vg_sigframe(&frame->vg, tst, flags, sigNo);
return sp;
}
/* 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 )
{
Addr sp;
ThreadState* tst = VG_(get_ThreadState)(tid);
if (flags & VKI_SA_SIGINFO)
sp = build_rt_sigframe(tst, sp_top_of_frame, siginfo, siguc,
flags, mask, restorer);
else
sp = build_sigframe(tst, sp_top_of_frame, siginfo, siguc,
flags, mask, restorer);
/* Set the thread so it will next run the handler. */
VG_(set_SP)(tid, sp);
VG_TRACK( post_reg_write, Vg_CoreSignal, tid, VG_O_STACK_PTR, sizeof(Addr));
tst->arch.vex.guest_IA = (Addr) handler;
/* We might have interrupted a repeating instruction that uses the guest
counter. Since our VEX requires that a new instruction will see a
guest counter == 0, we have to set it here. The old value will be
restored by restore_vg_sigframe. */
tst->arch.vex.guest_counter = 0;
/* This thread needs to be marked runnable, but we leave that the
caller to do. */
}
/*------------------------------------------------------------*/
/*--- 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.\n",
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_shadow1 = frame->vex_shadow1;
tst->arch.vex_shadow2 = frame->vex_shadow2;
/* HACK ALERT */
tst->arch.vex = frame->vex;
/* end HACK ALERT */
*sigNo = frame->sigNo_private;
return True;
}
static
SizeT restore_sigframe ( ThreadState *tst,
struct sigframe *frame, Int *sigNo )
{
if (restore_vg_sigframe(tst, &frame->vg, sigNo))
restore_sigregs(tst, frame->sc.sregs);
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_sigregs(tst, &frame->uc.uc_mcontext);
}
return sizeof(*frame);
}
/* EXPORTED */
void VG_(sigframe_destroy)( ThreadId tid, Bool isRT )
{
Addr sp;
ThreadState* tst;
SizeT size;
Int sigNo;
tst = VG_(get_ThreadState)(tid);
/* Correctly reestablish the frame base address. */
sp = tst->arch.vex.guest_SP;
if (!isRT)
size = restore_sigframe(tst, (struct sigframe *)sp, &sigNo);
else
size = restore_rt_sigframe(tst, (struct rt_sigframe *)sp, &sigNo);
/* same as for creation: we must announce the full memory (including
alignment), otherwise massif might fail on longjmp */
VG_TRACK( die_mem_stack_signal, sp - VG_STACK_REDZONE_SZB,
size + VG_STACK_REDZONE_SZB );
if (VG_(clo_trace_signals))
VG_(message)(
Vg_DebugMsg,
"VG_(sigframe_destroy) (thread %d): isRT=%d valid magic; IP=%#llx\n",
tid, isRT, tst->arch.vex.guest_IA);
/* tell the tools */
VG_TRACK( post_deliver_signal, tid, sigNo );
}
#endif /* VGA_s390x */
/*--------------------------------------------------------------------*/
/*--- end sigframe-s390x-linux.c ---*/
/*--------------------------------------------------------------------*/