| |
| /*--------------------------------------------------------------------*/ |
| /*--- Create/destroy signal delivery frames. ---*/ |
| /*--- sigframe-arm-linux.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, a dynamic binary instrumentation |
| framework. |
| |
| Copyright (C) 2000-2013 Nicholas Nethercote |
| njn@valgrind.org |
| Copyright (C) 2004-2013 Paul Mackerras |
| paulus@samba.org |
| Copyright (C) 2008-2013 Evan Geller |
| gaze@bea.ms |
| |
| 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_arm_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 uses the hack of dumping the vex guest state along with both |
| shadows in the frame, and restoring it afterwards from there, |
| rather than pulling it out of the ucontext. That means that signal |
| handlers which modify the ucontext and then return, expecting their |
| modifications to take effect, will have those modifications |
| ignored. This could be fixed properly with an hour or so more |
| effort. */ |
| |
| |
| struct vg_sig_private { |
| UInt magicPI; |
| UInt sigNo_private; |
| VexGuestARMState vex; |
| VexGuestARMState vex_shadow1; |
| VexGuestARMState vex_shadow2; |
| }; |
| |
| struct sigframe { |
| struct vki_ucontext uc; |
| unsigned long retcode[2]; |
| struct vg_sig_private vp; |
| }; |
| |
| struct rt_sigframe { |
| vki_siginfo_t info; |
| struct sigframe sig; |
| }; |
| |
| 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:", |
| addr, tid); |
| if (stackseg == NULL) |
| VG_(message)(Vg_UserMsg, " no stack segment"); |
| else |
| VG_(message)(Vg_UserMsg, " too small or bad protection modes"); |
| |
| /* 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; |
| } |
| |
| static void synth_ucontext( ThreadId tid, const vki_siginfo_t *si, |
| UWord trapno, UWord err, 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; |
| |
| # define SC2(reg,REG) sc->arm_##reg = tst->arch.vex.guest_##REG |
| SC2(r0,R0); |
| SC2(r1,R1); |
| SC2(r2,R2); |
| SC2(r3,R3); |
| SC2(r4,R4); |
| SC2(r5,R5); |
| SC2(r6,R6); |
| SC2(r7,R7); |
| SC2(r8,R8); |
| SC2(r9,R9); |
| SC2(r10,R10); |
| SC2(fp,R11); |
| SC2(ip,R12); |
| SC2(sp,R13); |
| SC2(lr,R14); |
| SC2(pc,R15T); |
| # undef SC2 |
| |
| sc->trap_no = trapno; |
| sc->error_code = err; |
| sc->fault_address = (UInt)si->_sifields._sigfault._addr; |
| } |
| |
| |
| static void build_sigframe(ThreadState *tst, |
| struct sigframe *frame, |
| const vki_siginfo_t *siginfo, |
| const struct vki_ucontext *siguc, |
| void *handler, UInt flags, |
| const vki_sigset_t *mask, |
| void *restorer){ |
| |
| UWord trapno; |
| UWord err; |
| Int sigNo = siginfo->si_signo; |
| struct vg_sig_private *priv = &frame->vp; |
| |
| VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, "signal handler frame", |
| (Addr)frame, offsetof(struct sigframe, vp)); |
| |
| if(siguc) { |
| trapno = siguc->uc_mcontext.trap_no; |
| err = siguc->uc_mcontext.error_code; |
| } else { |
| trapno = 0; |
| err = 0; |
| } |
| |
| synth_ucontext(tst->tid, siginfo, trapno, err, mask, &frame->uc); |
| |
| VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid, |
| (Addr)frame, offsetof(struct sigframe, vp)); |
| |
| priv->magicPI = 0x31415927; |
| priv->sigNo_private = sigNo; |
| priv->vex = tst->arch.vex; |
| priv->vex_shadow1 = tst->arch.vex_shadow1; |
| priv->vex_shadow2 = tst->arch.vex_shadow2; |
| |
| } |
| |
| |
| |
| /* 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 = sp_top_of_frame; |
| ThreadState *tst; |
| Int sigNo = siginfo->si_signo; |
| // Addr faultaddr; |
| UInt size; |
| |
| tst = VG_(get_ThreadState)(tid); |
| |
| size = flags & VKI_SA_SIGINFO ? sizeof(struct rt_sigframe) : |
| sizeof(struct sigframe); |
| |
| sp -= size; |
| sp = VG_ROUNDDN(sp, 16); |
| |
| if(!extend(tst, sp, size)) |
| I_die_here; // XXX Incorrect behavior |
| |
| |
| if (flags & VKI_SA_SIGINFO){ |
| struct rt_sigframe *rsf = (struct rt_sigframe *)sp; |
| |
| /* Track our writes to siginfo */ |
| VG_TRACK( pre_mem_write, Vg_CoreSignal, tst->tid, /* VVVVV */ |
| "signal handler siginfo", (Addr)rsf, |
| offsetof(struct rt_sigframe, sig)); |
| |
| VG_(memcpy)(&rsf->info, siginfo, sizeof(vki_siginfo_t)); |
| |
| if(sigNo == VKI_SIGILL && siginfo->si_code > 0) { |
| rsf->info._sifields._sigfault._addr = (Addr *) (tst)->arch.vex.guest_R12; /* IP */ |
| } |
| VG_TRACK( post_mem_write, Vg_CoreSignal, tst->tid, /* ^^^^^ */ |
| (Addr)rsf, offsetof(struct rt_sigframe, sig)); |
| |
| build_sigframe(tst, &rsf->sig, siginfo, siguc, |
| handler, flags, mask, restorer); |
| tst->arch.vex.guest_R1 = (Addr)&rsf->info; |
| tst->arch.vex.guest_R2 = (Addr)&rsf->sig.uc; |
| } |
| else { |
| build_sigframe(tst, (struct sigframe *)sp, siginfo, siguc, |
| handler, flags, mask, restorer); |
| } |
| |
| VG_(set_SP)(tid, sp); |
| VG_TRACK( post_reg_write, Vg_CoreSignal, tid, VG_O_STACK_PTR, |
| sizeof(Addr)); |
| tst->arch.vex.guest_R0 = sigNo; |
| |
| if (flags & VKI_SA_RESTORER) |
| tst->arch.vex.guest_R14 = (Addr)restorer; |
| else |
| tst->arch.vex.guest_R14 |
| = (flags & VKI_SA_SIGINFO) |
| ? (Addr)&VG_(arm_linux_SUBST_FOR_rt_sigreturn) |
| : (Addr)&VG_(arm_linux_SUBST_FOR_sigreturn); |
| |
| tst->arch.vex.guest_R15T = (Addr) handler; /* R15 == PC */ |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Destroying signal frames ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* EXPORTED */ |
| void VG_(sigframe_destroy)( ThreadId tid, Bool isRT ) |
| { |
| ThreadState *tst; |
| struct vg_sig_private *priv; |
| Addr sp; |
| UInt frame_size; |
| struct vki_sigcontext *mc; |
| Int sigNo; |
| Bool has_siginfo = isRT; |
| |
| vg_assert(VG_(is_valid_tid)(tid)); |
| tst = VG_(get_ThreadState)(tid); |
| sp = tst->arch.vex.guest_R13; |
| |
| if (has_siginfo) { |
| struct rt_sigframe *frame = (struct rt_sigframe *)sp; |
| frame_size = sizeof(*frame); |
| mc = &frame->sig.uc.uc_mcontext; |
| priv = &frame->sig.vp; |
| vg_assert(priv->magicPI == 0x31415927); |
| tst->sig_mask = frame->sig.uc.uc_sigmask; |
| } else { |
| struct sigframe *frame = (struct sigframe *)sp; |
| frame_size = sizeof(*frame); |
| mc = &frame->uc.uc_mcontext; |
| priv = &frame->vp; |
| vg_assert(priv->magicPI == 0x31415927); |
| tst->sig_mask = frame->uc.uc_sigmask; |
| /*tst->sig_mask.sig[0] = frame->uc.uc_mcontext.oldmask; |
| tst->sig_mask.sig[1] = frame->uc.uc_mcontext._unused[3]; |
| VG_(printf)("Setting signmask to %08x%08x\n",tst->sig_mask[0],tst->sig_mask[1]); |
| */ |
| } |
| tst->tmp_sig_mask = tst->sig_mask; |
| |
| sigNo = priv->sigNo_private; |
| |
| //XXX: restore regs |
| # define REST(reg,REG) tst->arch.vex.guest_##REG = mc->arm_##reg; |
| REST(r0,R0); |
| REST(r1,R1); |
| REST(r2,R2); |
| REST(r3,R3); |
| REST(r4,R4); |
| REST(r5,R5); |
| REST(r6,R6); |
| REST(r7,R7); |
| REST(r8,R8); |
| REST(r9,R9); |
| REST(r10,R10); |
| REST(fp,R11); |
| REST(ip,R12); |
| REST(sp,R13); |
| REST(lr,R14); |
| REST(pc,R15T); |
| # undef REST |
| |
| /* Uh, the next line makes all the REST() above pointless. */ |
| tst->arch.vex = priv->vex; |
| |
| tst->arch.vex_shadow1 = priv->vex_shadow1; |
| tst->arch.vex_shadow2 = priv->vex_shadow2; |
| |
| VG_TRACK( die_mem_stack_signal, sp - VG_STACK_REDZONE_SZB, |
| frame_size + VG_STACK_REDZONE_SZB ); |
| |
| if (VG_(clo_trace_signals)) |
| VG_(message)(Vg_DebugMsg, |
| "vg_pop_signal_frame (thread %d): " |
| "isRT=%d valid magic; PC=%#x\n", |
| tid, has_siginfo, tst->arch.vex.guest_R15T); |
| |
| /* tell the tools */ |
| VG_TRACK( post_deliver_signal, tid, sigNo ); |
| } |
| |
| #endif // defined(VGP_arm_linux) |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end sigframe-arm-linux.c ---*/ |
| /*--------------------------------------------------------------------*/ |
