| /* |
| * Copyright (C) 2003 PathScale, Inc. |
| * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
| * Licensed under the GPL |
| */ |
| |
| |
| #include <linux/personality.h> |
| #include <linux/ptrace.h> |
| #include <linux/kernel.h> |
| #include <asm/unistd.h> |
| #include <asm/uaccess.h> |
| #include <asm/ucontext.h> |
| #include <frame_kern.h> |
| #include <skas.h> |
| |
| #ifdef CONFIG_X86_32 |
| |
| /* |
| * 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 inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave) |
| { |
| struct _fpxreg *st = NULL; |
| unsigned long twd = (unsigned long) fxsave->twd; |
| unsigned long tag; |
| unsigned long ret = 0xffff0000; |
| int i; |
| |
| #define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16) |
| |
| for (i = 0; i < 8; i++) { |
| if (twd & 0x1) { |
| st = (struct _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 int convert_fxsr_to_user(struct _fpstate __user *buf, |
| struct user_fxsr_struct *fxsave) |
| { |
| unsigned long env[7]; |
| struct _fpreg __user *to; |
| struct _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; |
| |
| if (__copy_to_user(buf, env, 7 * sizeof(unsigned long))) |
| return 1; |
| |
| to = &buf->_st[0]; |
| from = (struct _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; |
| |
| if (__put_user(*f, t) || |
| __put_user(*(f + 1), t + 1) || |
| __put_user(from->exponent, &to->exponent)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave, |
| struct _fpstate __user *buf) |
| { |
| unsigned long env[7]; |
| struct _fpxreg *to; |
| struct _fpreg __user *from; |
| int i; |
| |
| if (copy_from_user( env, buf, 7 * sizeof(long))) |
| return 1; |
| |
| 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 _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; |
| |
| if (__get_user(*t, f) || |
| __get_user(*(t + 1), f + 1) || |
| __get_user(to->exponent, &from->exponent)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| extern int have_fpx_regs; |
| |
| #endif |
| |
| static int copy_sc_from_user(struct pt_regs *regs, |
| struct sigcontext __user *from) |
| { |
| struct sigcontext sc; |
| int err, pid; |
| |
| /* Always make any pending restarted system calls return -EINTR */ |
| current_thread_info()->restart_block.fn = do_no_restart_syscall; |
| |
| err = copy_from_user(&sc, from, sizeof(sc)); |
| if (err) |
| return err; |
| |
| #define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname |
| |
| #ifdef CONFIG_X86_32 |
| GETREG(GS, gs); |
| GETREG(FS, fs); |
| GETREG(ES, es); |
| GETREG(DS, ds); |
| #endif |
| GETREG(DI, di); |
| GETREG(SI, si); |
| GETREG(BP, bp); |
| GETREG(SP, sp); |
| GETREG(BX, bx); |
| GETREG(DX, dx); |
| GETREG(CX, cx); |
| GETREG(AX, ax); |
| GETREG(IP, ip); |
| |
| #ifdef CONFIG_X86_64 |
| GETREG(R8, r8); |
| GETREG(R9, r9); |
| GETREG(R10, r10); |
| GETREG(R11, r11); |
| GETREG(R12, r12); |
| GETREG(R13, r13); |
| GETREG(R14, r14); |
| GETREG(R15, r15); |
| #endif |
| |
| GETREG(CS, cs); |
| GETREG(EFLAGS, flags); |
| #ifdef CONFIG_X86_32 |
| GETREG(SS, ss); |
| #endif |
| |
| #undef GETREG |
| |
| pid = userspace_pid[current_thread_info()->cpu]; |
| #ifdef CONFIG_X86_32 |
| if (have_fpx_regs) { |
| struct user_fxsr_struct fpx; |
| |
| err = copy_from_user(&fpx, |
| &((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0], |
| sizeof(struct user_fxsr_struct)); |
| if (err) |
| return 1; |
| |
| err = convert_fxsr_from_user(&fpx, sc.fpstate); |
| if (err) |
| return 1; |
| |
| err = restore_fpx_registers(pid, (unsigned long *) &fpx); |
| if (err < 0) { |
| printk(KERN_ERR "copy_sc_from_user - " |
| "restore_fpx_registers failed, errno = %d\n", |
| -err); |
| return 1; |
| } |
| } else |
| #endif |
| { |
| struct user_i387_struct fp; |
| |
| err = copy_from_user(&fp, sc.fpstate, |
| sizeof(struct user_i387_struct)); |
| if (err) |
| return 1; |
| |
| err = restore_fp_registers(pid, (unsigned long *) &fp); |
| if (err < 0) { |
| printk(KERN_ERR "copy_sc_from_user - " |
| "restore_fp_registers failed, errno = %d\n", |
| -err); |
| return 1; |
| } |
| } |
| return 0; |
| } |
| |
| static int copy_sc_to_user(struct sigcontext __user *to, |
| struct _fpstate __user *to_fp, struct pt_regs *regs, |
| unsigned long mask) |
| { |
| struct sigcontext sc; |
| struct faultinfo * fi = ¤t->thread.arch.faultinfo; |
| int err, pid; |
| memset(&sc, 0, sizeof(struct sigcontext)); |
| |
| #define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno] |
| |
| #ifdef CONFIG_X86_32 |
| PUTREG(GS, gs); |
| PUTREG(FS, fs); |
| PUTREG(ES, es); |
| PUTREG(DS, ds); |
| #endif |
| PUTREG(DI, di); |
| PUTREG(SI, si); |
| PUTREG(BP, bp); |
| PUTREG(SP, sp); |
| PUTREG(BX, bx); |
| PUTREG(DX, dx); |
| PUTREG(CX, cx); |
| PUTREG(AX, ax); |
| #ifdef CONFIG_X86_64 |
| PUTREG(R8, r8); |
| PUTREG(R9, r9); |
| PUTREG(R10, r10); |
| PUTREG(R11, r11); |
| PUTREG(R12, r12); |
| PUTREG(R13, r13); |
| PUTREG(R14, r14); |
| PUTREG(R15, r15); |
| #endif |
| |
| sc.cr2 = fi->cr2; |
| sc.err = fi->error_code; |
| sc.trapno = fi->trap_no; |
| PUTREG(IP, ip); |
| PUTREG(CS, cs); |
| PUTREG(EFLAGS, flags); |
| #ifdef CONFIG_X86_32 |
| PUTREG(SP, sp_at_signal); |
| PUTREG(SS, ss); |
| #endif |
| #undef PUTREG |
| sc.oldmask = mask; |
| sc.fpstate = to_fp; |
| |
| err = copy_to_user(to, &sc, sizeof(struct sigcontext)); |
| if (err) |
| return 1; |
| |
| pid = userspace_pid[current_thread_info()->cpu]; |
| |
| #ifdef CONFIG_X86_32 |
| if (have_fpx_regs) { |
| struct user_fxsr_struct fpx; |
| |
| err = save_fpx_registers(pid, (unsigned long *) &fpx); |
| if (err < 0){ |
| printk(KERN_ERR "copy_sc_to_user - save_fpx_registers " |
| "failed, errno = %d\n", err); |
| return 1; |
| } |
| |
| err = convert_fxsr_to_user(to_fp, &fpx); |
| if (err) |
| return 1; |
| |
| err |= __put_user(fpx.swd, &to_fp->status); |
| err |= __put_user(X86_FXSR_MAGIC, &to_fp->magic); |
| if (err) |
| return 1; |
| |
| if (copy_to_user(&to_fp->_fxsr_env[0], &fpx, |
| sizeof(struct user_fxsr_struct))) |
| return 1; |
| } else |
| #endif |
| { |
| struct user_i387_struct fp; |
| |
| err = save_fp_registers(pid, (unsigned long *) &fp); |
| if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct))) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_X86_32 |
| static int copy_ucontext_to_user(struct ucontext __user *uc, |
| struct _fpstate __user *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, 0); |
| err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set)); |
| return err; |
| } |
| |
| struct sigframe |
| { |
| char __user *pretcode; |
| int sig; |
| struct sigcontext sc; |
| struct _fpstate fpstate; |
| unsigned long extramask[_NSIG_WORDS-1]; |
| char retcode[8]; |
| }; |
| |
| struct rt_sigframe |
| { |
| char __user *pretcode; |
| int sig; |
| struct siginfo __user *pinfo; |
| void __user *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 __user *restorer; |
| int err = 0; |
| |
| /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */ |
| stack_top = ((stack_top + 4) & -16UL) - 4; |
| frame = (struct sigframe __user *) stack_top - 1; |
| if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| return 1; |
| |
| restorer = 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, &frame->fpstate, regs, mask->sig[0]); |
| 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_AX(regs) = (unsigned long) sig; |
| PT_REGS_DX(regs) = (unsigned long) 0; |
| PT_REGS_CX(regs) = (unsigned long) 0; |
| 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 __user *restorer; |
| int err = 0; |
| |
| stack_top &= -8UL; |
| frame = (struct rt_sigframe __user *) stack_top - 1; |
| if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| return 1; |
| |
| restorer = 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_AX(regs) = (unsigned long) sig; |
| PT_REGS_DX(regs) = (unsigned long) &frame->info; |
| PT_REGS_CX(regs) = (unsigned long) &frame->uc; |
| return 0; |
| } |
| |
| long sys_sigreturn(struct pt_regs *regs) |
| { |
| unsigned long sp = PT_REGS_SP(¤t->thread.regs); |
| struct sigframe __user *frame = (struct sigframe __user *)(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; |
| |
| set_current_blocked(&set); |
| |
| 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; |
| } |
| |
| #else |
| |
| struct rt_sigframe |
| { |
| char __user *pretcode; |
| struct ucontext uc; |
| struct siginfo info; |
| struct _fpstate fpstate; |
| }; |
| |
| int setup_signal_stack_si(unsigned long stack_top, int sig, |
| struct k_sigaction *ka, struct pt_regs * regs, |
| siginfo_t *info, sigset_t *set) |
| { |
| struct rt_sigframe __user *frame; |
| int err = 0; |
| struct task_struct *me = current; |
| |
| frame = (struct rt_sigframe __user *) |
| round_down(stack_top - sizeof(struct rt_sigframe), 16); |
| /* Subtract 128 for a red zone and 8 for proper alignment */ |
| frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8); |
| |
| if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| goto out; |
| |
| if (ka->sa.sa_flags & SA_SIGINFO) { |
| err |= copy_siginfo_to_user(&frame->info, info); |
| if (err) |
| goto out; |
| } |
| |
| /* Create the ucontext. */ |
| err |= __put_user(0, &frame->uc.uc_flags); |
| err |= __put_user(0, &frame->uc.uc_link); |
| err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp); |
| err |= __put_user(sas_ss_flags(PT_REGS_SP(regs)), |
| &frame->uc.uc_stack.ss_flags); |
| err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size); |
| err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs, |
| set->sig[0]); |
| err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate); |
| if (sizeof(*set) == 16) { |
| err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]); |
| err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]); |
| } |
| else |
| err |= __copy_to_user(&frame->uc.uc_sigmask, set, |
| sizeof(*set)); |
| |
| /* |
| * Set up to return from userspace. If provided, use a stub |
| * already in userspace. |
| */ |
| /* x86-64 should always use SA_RESTORER. */ |
| if (ka->sa.sa_flags & SA_RESTORER) |
| err |= __put_user(ka->sa.sa_restorer, &frame->pretcode); |
| else |
| /* could use a vstub here */ |
| return err; |
| |
| if (err) |
| return err; |
| |
| /* Set up registers for signal handler */ |
| { |
| struct exec_domain *ed = current_thread_info()->exec_domain; |
| if (unlikely(ed && ed->signal_invmap && sig < 32)) |
| sig = ed->signal_invmap[sig]; |
| } |
| |
| PT_REGS_SP(regs) = (unsigned long) frame; |
| PT_REGS_DI(regs) = sig; |
| /* In case the signal handler was declared without prototypes */ |
| PT_REGS_AX(regs) = 0; |
| |
| /* |
| * This also works for non SA_SIGINFO handlers because they expect the |
| * next argument after the signal number on the stack. |
| */ |
| PT_REGS_SI(regs) = (unsigned long) &frame->info; |
| PT_REGS_DX(regs) = (unsigned long) &frame->uc; |
| PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler; |
| out: |
| return err; |
| } |
| #endif |
| |
| long sys_rt_sigreturn(struct pt_regs *regs) |
| { |
| unsigned long sp = PT_REGS_SP(¤t->thread.regs); |
| struct rt_sigframe __user *frame = |
| (struct rt_sigframe __user *)(sp - sizeof(long)); |
| struct ucontext __user *uc = &frame->uc; |
| sigset_t set; |
| |
| if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set))) |
| goto segfault; |
| |
| set_current_blocked(&set); |
| |
| 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; |
| } |
| |
| #ifdef CONFIG_X86_32 |
| long ptregs_sigreturn(void) |
| { |
| return sys_sigreturn(NULL); |
| } |
| long ptregs_rt_sigreturn(void) |
| { |
| return sys_rt_sigreturn(NULL); |
| } |
| #endif |