| /* |
| * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com) |
| * Licensed under the GPL |
| */ |
| |
| #include "linux/signal.h" |
| #include "linux/ptrace.h" |
| #include "asm/current.h" |
| #include "asm/ucontext.h" |
| #include "asm/uaccess.h" |
| #include "asm/unistd.h" |
| #include "frame_kern.h" |
| #include "sigcontext.h" |
| #include "registers.h" |
| #include "mode.h" |
| |
| #ifdef CONFIG_MODE_SKAS |
| |
| #include "skas.h" |
| |
| static int copy_sc_from_user_skas(struct pt_regs *regs, |
| struct sigcontext *from) |
| { |
| struct sigcontext sc; |
| unsigned long fpregs[HOST_FP_SIZE]; |
| int err; |
| |
| err = copy_from_user(&sc, from, sizeof(sc)); |
| err |= copy_from_user(fpregs, sc.fpstate, sizeof(fpregs)); |
| if(err) |
| return(err); |
| |
| REGS_GS(regs->regs.skas.regs) = sc.gs; |
| REGS_FS(regs->regs.skas.regs) = sc.fs; |
| REGS_ES(regs->regs.skas.regs) = sc.es; |
| REGS_DS(regs->regs.skas.regs) = sc.ds; |
| REGS_EDI(regs->regs.skas.regs) = sc.edi; |
| REGS_ESI(regs->regs.skas.regs) = sc.esi; |
| REGS_EBP(regs->regs.skas.regs) = sc.ebp; |
| REGS_SP(regs->regs.skas.regs) = sc.esp; |
| REGS_EBX(regs->regs.skas.regs) = sc.ebx; |
| REGS_EDX(regs->regs.skas.regs) = sc.edx; |
| REGS_ECX(regs->regs.skas.regs) = sc.ecx; |
| REGS_EAX(regs->regs.skas.regs) = sc.eax; |
| REGS_IP(regs->regs.skas.regs) = sc.eip; |
| REGS_CS(regs->regs.skas.regs) = sc.cs; |
| REGS_EFLAGS(regs->regs.skas.regs) = sc.eflags; |
| REGS_SS(regs->regs.skas.regs) = sc.ss; |
| |
| err = restore_fp_registers(userspace_pid[0], fpregs); |
| if(err < 0){ |
| printk("copy_sc_from_user_skas - PTRACE_SETFPREGS failed, " |
| "errno = %d\n", err); |
| return(1); |
| } |
| |
| return(0); |
| } |
| |
| int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp, |
| struct pt_regs *regs) |
| { |
| struct sigcontext sc; |
| unsigned long fpregs[HOST_FP_SIZE]; |
| struct faultinfo * fi = ¤t->thread.arch.faultinfo; |
| int err; |
| |
| sc.gs = REGS_GS(regs->regs.skas.regs); |
| sc.fs = REGS_FS(regs->regs.skas.regs); |
| sc.es = REGS_ES(regs->regs.skas.regs); |
| sc.ds = REGS_DS(regs->regs.skas.regs); |
| sc.edi = REGS_EDI(regs->regs.skas.regs); |
| sc.esi = REGS_ESI(regs->regs.skas.regs); |
| sc.ebp = REGS_EBP(regs->regs.skas.regs); |
| sc.esp = REGS_SP(regs->regs.skas.regs); |
| sc.ebx = REGS_EBX(regs->regs.skas.regs); |
| sc.edx = REGS_EDX(regs->regs.skas.regs); |
| sc.ecx = REGS_ECX(regs->regs.skas.regs); |
| sc.eax = REGS_EAX(regs->regs.skas.regs); |
| sc.eip = REGS_IP(regs->regs.skas.regs); |
| sc.cs = REGS_CS(regs->regs.skas.regs); |
| sc.eflags = REGS_EFLAGS(regs->regs.skas.regs); |
| sc.esp_at_signal = regs->regs.skas.regs[UESP]; |
| sc.ss = regs->regs.skas.regs[SS]; |
| sc.cr2 = fi->cr2; |
| sc.err = fi->error_code; |
| sc.trapno = fi->trap_no; |
| |
| err = save_fp_registers(userspace_pid[0], fpregs); |
| if(err < 0){ |
| printk("copy_sc_to_user_skas - PTRACE_GETFPREGS failed, " |
| "errno = %d\n", err); |
| return(1); |
| } |
| to_fp = (to_fp ? to_fp : (struct _fpstate *) (to + 1)); |
| sc.fpstate = to_fp; |
| |
| if(err) |
| return(err); |
| |
| return(copy_to_user(to, &sc, sizeof(sc)) || |
| copy_to_user(to_fp, fpregs, sizeof(fpregs))); |
| } |
| #endif |
| |
| #ifdef CONFIG_MODE_TT |
| |
| /* These copy a sigcontext to/from userspace. They copy the fpstate pointer, |
| * blowing away the old, good one. So, that value is saved, and then restored |
| * after the sigcontext copy. In copy_from, the variable holding the saved |
| * fpstate pointer, and the sigcontext that it should be restored to are both |
| * in the kernel, so we can just restore using an assignment. In copy_to, the |
| * saved pointer is in the kernel, but the sigcontext is in userspace, so we |
| * copy_to_user it. |
| */ |
| int copy_sc_from_user_tt(struct sigcontext *to, struct sigcontext *from, |
| int fpsize) |
| { |
| struct _fpstate *to_fp, *from_fp; |
| unsigned long sigs; |
| int err; |
| |
| to_fp = to->fpstate; |
| sigs = to->oldmask; |
| err = copy_from_user(to, from, sizeof(*to)); |
| from_fp = to->fpstate; |
| to->oldmask = sigs; |
| to->fpstate = to_fp; |
| if(to_fp != NULL) |
| err |= copy_from_user(to_fp, from_fp, fpsize); |
| return(err); |
| } |
| |
| int copy_sc_to_user_tt(struct sigcontext *to, struct _fpstate *fp, |
| struct sigcontext *from, int fpsize) |
| { |
| struct _fpstate *to_fp, *from_fp; |
| int err; |
| |
| to_fp = (fp ? fp : (struct _fpstate *) (to + 1)); |
| from_fp = from->fpstate; |
| err = copy_to_user(to, from, sizeof(*to)); |
| if(from_fp != NULL){ |
| err |= copy_to_user(&to->fpstate, &to_fp, sizeof(to->fpstate)); |
| err |= copy_to_user(to_fp, from_fp, fpsize); |
| } |
| return(err); |
| } |
| #endif |
| |
| static int copy_sc_from_user(struct pt_regs *to, void __user *from) |
| { |
| int ret; |
| |
| ret = CHOOSE_MODE(copy_sc_from_user_tt(UPT_SC(&to->regs), from, |
| sizeof(struct _fpstate)), |
| copy_sc_from_user_skas(to, from)); |
| return(ret); |
| } |
| |
| static int copy_sc_to_user(struct sigcontext *to, struct _fpstate *fp, |
| struct pt_regs *from) |
| { |
| return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs), |
| sizeof(*fp)), |
| copy_sc_to_user_skas(to, fp, from))); |
| } |
| |
| static int copy_ucontext_to_user(struct ucontext *uc, struct _fpstate *fp, |
| sigset_t *set, unsigned long sp) |
| { |
| int err = 0; |
| |
| err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp); |
| err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags); |
| err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size); |
| err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs); |
| err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set)); |
| return(err); |
| } |
| |
| struct sigframe |
| { |
| char *pretcode; |
| int sig; |
| struct sigcontext sc; |
| struct _fpstate fpstate; |
| unsigned long extramask[_NSIG_WORDS-1]; |
| char retcode[8]; |
| }; |
| |
| struct rt_sigframe |
| { |
| char *pretcode; |
| int sig; |
| struct siginfo *pinfo; |
| void *puc; |
| struct siginfo info; |
| struct ucontext uc; |
| struct _fpstate fpstate; |
| char retcode[8]; |
| }; |
| |
| int setup_signal_stack_sc(unsigned long stack_top, int sig, |
| struct k_sigaction *ka, struct pt_regs *regs, |
| sigset_t *mask) |
| { |
| struct sigframe __user *frame; |
| void *restorer; |
| int err = 0; |
| |
| stack_top &= -8UL; |
| frame = (struct sigframe *) stack_top - 1; |
| if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| return 1; |
| |
| restorer = (void *) frame->retcode; |
| if(ka->sa.sa_flags & SA_RESTORER) |
| restorer = ka->sa.sa_restorer; |
| |
| err |= __put_user(restorer, &frame->pretcode); |
| err |= __put_user(sig, &frame->sig); |
| err |= copy_sc_to_user(&frame->sc, NULL, regs); |
| err |= __put_user(mask->sig[0], &frame->sc.oldmask); |
| if (_NSIG_WORDS > 1) |
| err |= __copy_to_user(&frame->extramask, &mask->sig[1], |
| sizeof(frame->extramask)); |
| |
| /* |
| * This is popl %eax ; movl $,%eax ; int $0x80 |
| * |
| * WE DO NOT USE IT ANY MORE! It's only left here for historical |
| * reasons and because gdb uses it as a signature to notice |
| * signal handler stack frames. |
| */ |
| err |= __put_user(0xb858, (short __user *)(frame->retcode+0)); |
| err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2)); |
| err |= __put_user(0x80cd, (short __user *)(frame->retcode+6)); |
| |
| if(err) |
| return(err); |
| |
| PT_REGS_SP(regs) = (unsigned long) frame; |
| PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler; |
| PT_REGS_EAX(regs) = (unsigned long) sig; |
| PT_REGS_EDX(regs) = (unsigned long) 0; |
| PT_REGS_ECX(regs) = (unsigned long) 0; |
| |
| if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED)) |
| ptrace_notify(SIGTRAP); |
| return(0); |
| } |
| |
| int setup_signal_stack_si(unsigned long stack_top, int sig, |
| struct k_sigaction *ka, struct pt_regs *regs, |
| siginfo_t *info, sigset_t *mask) |
| { |
| struct rt_sigframe __user *frame; |
| void *restorer; |
| int err = 0; |
| |
| stack_top &= -8UL; |
| frame = (struct rt_sigframe *) stack_top - 1; |
| if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| return 1; |
| |
| restorer = (void *) frame->retcode; |
| if(ka->sa.sa_flags & SA_RESTORER) |
| restorer = ka->sa.sa_restorer; |
| |
| err |= __put_user(restorer, &frame->pretcode); |
| err |= __put_user(sig, &frame->sig); |
| err |= __put_user(&frame->info, &frame->pinfo); |
| err |= __put_user(&frame->uc, &frame->puc); |
| err |= copy_siginfo_to_user(&frame->info, info); |
| err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask, |
| PT_REGS_SP(regs)); |
| |
| /* |
| * This is movl $,%eax ; int $0x80 |
| * |
| * WE DO NOT USE IT ANY MORE! It's only left here for historical |
| * reasons and because gdb uses it as a signature to notice |
| * signal handler stack frames. |
| */ |
| err |= __put_user(0xb8, (char __user *)(frame->retcode+0)); |
| err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1)); |
| err |= __put_user(0x80cd, (short __user *)(frame->retcode+5)); |
| |
| if(err) |
| return(err); |
| |
| PT_REGS_SP(regs) = (unsigned long) frame; |
| PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler; |
| PT_REGS_EAX(regs) = (unsigned long) sig; |
| PT_REGS_EDX(regs) = (unsigned long) &frame->info; |
| PT_REGS_ECX(regs) = (unsigned long) &frame->uc; |
| |
| if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED)) |
| ptrace_notify(SIGTRAP); |
| return(0); |
| } |
| |
| long sys_sigreturn(struct pt_regs regs) |
| { |
| unsigned long sp = PT_REGS_SP(¤t->thread.regs); |
| struct sigframe __user *frame = (struct sigframe *)(sp - 8); |
| sigset_t set; |
| struct sigcontext __user *sc = &frame->sc; |
| unsigned long __user *oldmask = &sc->oldmask; |
| unsigned long __user *extramask = frame->extramask; |
| int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long); |
| |
| if(copy_from_user(&set.sig[0], oldmask, sizeof(set.sig[0])) || |
| copy_from_user(&set.sig[1], extramask, sig_size)) |
| goto segfault; |
| |
| sigdelsetmask(&set, ~_BLOCKABLE); |
| |
| spin_lock_irq(¤t->sighand->siglock); |
| current->blocked = set; |
| recalc_sigpending(); |
| spin_unlock_irq(¤t->sighand->siglock); |
| |
| if(copy_sc_from_user(¤t->thread.regs, sc)) |
| goto segfault; |
| |
| /* Avoid ERESTART handling */ |
| PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1; |
| return(PT_REGS_SYSCALL_RET(¤t->thread.regs)); |
| |
| segfault: |
| force_sig(SIGSEGV, current); |
| return 0; |
| } |
| |
| long sys_rt_sigreturn(struct pt_regs regs) |
| { |
| unsigned long __user sp = PT_REGS_SP(¤t->thread.regs); |
| struct rt_sigframe __user *frame = (struct rt_sigframe *) (sp - 4); |
| sigset_t set; |
| struct ucontext __user *uc = &frame->uc; |
| int sig_size = _NSIG_WORDS * sizeof(unsigned long); |
| |
| if(copy_from_user(&set, &uc->uc_sigmask, sig_size)) |
| goto segfault; |
| |
| sigdelsetmask(&set, ~_BLOCKABLE); |
| |
| spin_lock_irq(¤t->sighand->siglock); |
| current->blocked = set; |
| recalc_sigpending(); |
| spin_unlock_irq(¤t->sighand->siglock); |
| |
| if(copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext)) |
| goto segfault; |
| |
| /* Avoid ERESTART handling */ |
| PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1; |
| return(PT_REGS_SYSCALL_RET(¤t->thread.regs)); |
| |
| segfault: |
| force_sig(SIGSEGV, current); |
| return 0; |
| } |
| |
| /* |
| * Overrides for Emacs so that we follow Linus's tabbing style. |
| * Emacs will notice this stuff at the end of the file and automatically |
| * adjust the settings for this buffer only. This must remain at the end |
| * of the file. |
| * --------------------------------------------------------------------------- |
| * Local variables: |
| * c-file-style: "linux" |
| * End: |
| */ |