arch/um/sys-x86_64/signal.c - kernel/msm - Gitiles

 /*
  * 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"

 static int copy_sc_from_user(struct pt_regs *regs,
 			     struct sigcontext __user *from)
 {
 	struct sigcontext sc;
 	struct user_i387_struct fp;
 	void __user *buf;
 	int err;

 	err = copy_from_user(&sc, from, sizeof(sc));
 	if (err)
 		return err;

 #define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname

 	GETREG(R8, r8);
 	GETREG(R9, r9);
 	GETREG(R10, r10);
 	GETREG(R11, r11);
 	GETREG(R12, r12);
 	GETREG(R13, r13);
 	GETREG(R14, r14);
 	GETREG(R15, r15);
 	GETREG(RDI, di);
 	GETREG(RSI, si);
 	GETREG(RBP, bp);
 	GETREG(RBX, bx);
 	GETREG(RDX, dx);
 	GETREG(RAX, ax);
 	GETREG(RCX, cx);
 	GETREG(SP, sp);
 	GETREG(IP, ip);
 	GETREG(EFLAGS, flags);
 	GETREG(CS, cs);
 #undef GETREG

 	buf = sc.fpstate;

 	err = copy_from_user(&fp, buf, sizeof(struct user_i387_struct));
 	if (err)
 		return 1;

 	err = restore_fp_registers(userspace_pid[current_thread_info()->cpu],
 				   (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, unsigned long sp)
 {
 	struct faultinfo * fi = &current->thread.arch.faultinfo;
 	struct sigcontext sc;
 	struct user_i387_struct fp;
 	int err = 0;
 	memset(&sc, 0, sizeof(struct sigcontext));

 #define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]

 	PUTREG(RDI, di);
 	PUTREG(RSI, si);
 	PUTREG(RBP, bp);
 	/*
 	 * Must use original RSP, which is passed in, rather than what's in
 	 * signal frame.
 	 */
 	sc.sp = sp;
 	PUTREG(RBX, bx);
 	PUTREG(RDX, dx);
 	PUTREG(RCX, cx);
 	PUTREG(RAX, ax);
 	PUTREG(R8, r8);
 	PUTREG(R9, r9);
 	PUTREG(R10, r10);
 	PUTREG(R11, r11);
 	PUTREG(R12, r12);
 	PUTREG(R13, r13);
 	PUTREG(R14, r14);
 	PUTREG(R15, r15);
 	PUTREG(CS, cs); /* XXX x86_64 doesn't do this */

 	sc.cr2 = fi->cr2;
 	sc.err = fi->error_code;
 	sc.trapno = fi->trap_no;

 	PUTREG(IP, ip);
 	PUTREG(EFLAGS, flags);
 #undef PUTREG

 	sc.oldmask = mask;

 	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
 	if (err)
 		return 1;

 	err = save_fp_registers(userspace_pid[current_thread_info()->cpu],
 				(unsigned long *) &fp);
 	if (err < 0) {
 		printk(KERN_ERR "copy_sc_from_user - restore_fp_registers "
 		       "failed, errno = %d\n", -err);
 		return 1;
 	}

 	if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
 		return 1;

 	return err;
 }

 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;
 	unsigned long save_sp = PT_REGS_RSP(regs);
 	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;
 	}

 	/*
 	 * Update SP now because the page fault handler refuses to extend
 	 * the stack if the faulting address is too far below the current
 	 * SP, which frame now certainly is.  If there's an error, the original
 	 * value is restored on the way out.
 	 * When writing the sigcontext to the stack, we have to write the
 	 * original value, so that's passed to copy_sc_to_user, which does
 	 * the right thing with it.
 	 */
 	PT_REGS_RSP(regs) = (unsigned long) frame;

 	/* 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(save_sp),
 			  &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], save_sp);
 	err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
 	if (sizeof(*set) == 16) {
 		__put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
 		__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 */
 		goto restore_sp;

 	if (err)
 		goto restore_sp;

 	/* 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_RDI(regs) = sig;
 	/* In case the signal handler was declared without prototypes */
 	PT_REGS_RAX(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_RSI(regs) = (unsigned long) &frame->info;
 	PT_REGS_RDX(regs) = (unsigned long) &frame->uc;
 	PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler;
  out:
 	return err;

 restore_sp:
 	PT_REGS_RSP(regs) = save_sp;
 	return err;
 }

 long sys_rt_sigreturn(struct pt_regs *regs)
 {
 	unsigned long sp = PT_REGS_SP(&current->thread.regs);
 	struct rt_sigframe __user *frame =
 		(struct rt_sigframe __user *)(sp - 8);
 	struct ucontext __user *uc = &frame->uc;
 	sigset_t set;

 	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
 		goto segfault;

 	sigdelsetmask(&set, ~_BLOCKABLE);
 	set_current_blocked(&set);

 	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
 		goto segfault;

 	/* Avoid ERESTART handling */
 	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
 	return PT_REGS_SYSCALL_RET(&current->thread.regs);

  segfault:
 	force_sig(SIGSEGV, current);
 	return 0;
 }
	/*
	* 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"

	static int copy_sc_from_user(struct pt_regs *regs,
	struct sigcontext __user *from)
	{
	struct sigcontext sc;
	struct user_i387_struct fp;
	void __user *buf;
	int err;

	err = copy_from_user(&sc, from, sizeof(sc));
	if (err)
	return err;

	#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname

	GETREG(R8, r8);
	GETREG(R9, r9);
	GETREG(R10, r10);
	GETREG(R11, r11);
	GETREG(R12, r12);
	GETREG(R13, r13);
	GETREG(R14, r14);
	GETREG(R15, r15);
	GETREG(RDI, di);
	GETREG(RSI, si);
	GETREG(RBP, bp);
	GETREG(RBX, bx);
	GETREG(RDX, dx);
	GETREG(RAX, ax);
	GETREG(RCX, cx);
	GETREG(SP, sp);
	GETREG(IP, ip);
	GETREG(EFLAGS, flags);
	GETREG(CS, cs);
	#undef GETREG

	buf = sc.fpstate;

	err = copy_from_user(&fp, buf, sizeof(struct user_i387_struct));
	if (err)
	return 1;

	err = restore_fp_registers(userspace_pid[current_thread_info()->cpu],
	(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, unsigned long sp)
	{
	struct faultinfo * fi = &current->thread.arch.faultinfo;
	struct sigcontext sc;
	struct user_i387_struct fp;
	int err = 0;
	memset(&sc, 0, sizeof(struct sigcontext));

	#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]

	PUTREG(RDI, di);
	PUTREG(RSI, si);
	PUTREG(RBP, bp);
	/*
	* Must use original RSP, which is passed in, rather than what's in
	* signal frame.
	*/
	sc.sp = sp;
	PUTREG(RBX, bx);
	PUTREG(RDX, dx);
	PUTREG(RCX, cx);
	PUTREG(RAX, ax);
	PUTREG(R8, r8);
	PUTREG(R9, r9);
	PUTREG(R10, r10);
	PUTREG(R11, r11);
	PUTREG(R12, r12);
	PUTREG(R13, r13);
	PUTREG(R14, r14);
	PUTREG(R15, r15);
	PUTREG(CS, cs); /* XXX x86_64 doesn't do this */

	sc.cr2 = fi->cr2;
	sc.err = fi->error_code;
	sc.trapno = fi->trap_no;

	PUTREG(IP, ip);
	PUTREG(EFLAGS, flags);
	#undef PUTREG

	sc.oldmask = mask;

	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
	if (err)
	return 1;

	err = save_fp_registers(userspace_pid[current_thread_info()->cpu],
	(unsigned long *) &fp);
	if (err < 0) {
	printk(KERN_ERR "copy_sc_from_user - restore_fp_registers "
	"failed, errno = %d\n", -err);
	return 1;
	}

	if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
	return 1;

	return err;
	}

	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;
	unsigned long save_sp = PT_REGS_RSP(regs);
	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;
	}

	/*
	* Update SP now because the page fault handler refuses to extend
	* the stack if the faulting address is too far below the current
	* SP, which frame now certainly is. If there's an error, the original
	* value is restored on the way out.
	* When writing the sigcontext to the stack, we have to write the
	* original value, so that's passed to copy_sc_to_user, which does
	* the right thing with it.
	*/
	PT_REGS_RSP(regs) = (unsigned long) frame;

	/* 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(save_sp),
	&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], save_sp);
	err \|= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
	if (sizeof(*set) == 16) {
	__put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
	__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 */
	goto restore_sp;

	if (err)
	goto restore_sp;

	/* 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_RDI(regs) = sig;
	/* In case the signal handler was declared without prototypes */
	PT_REGS_RAX(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_RSI(regs) = (unsigned long) &frame->info;
	PT_REGS_RDX(regs) = (unsigned long) &frame->uc;
	PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler;
	out:
	return err;

	restore_sp:
	PT_REGS_RSP(regs) = save_sp;
	return err;
	}

	long sys_rt_sigreturn(struct pt_regs *regs)
	{
	unsigned long sp = PT_REGS_SP(&current->thread.regs);
	struct rt_sigframe __user *frame =
	(struct rt_sigframe __user *)(sp - 8);
	struct ucontext __user *uc = &frame->uc;
	sigset_t set;

	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
	goto segfault;

	sigdelsetmask(&set, ~_BLOCKABLE);
	set_current_blocked(&set);

	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
	goto segfault;

	/* Avoid ERESTART handling */
	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
	return PT_REGS_SYSCALL_RET(&current->thread.regs);

	segfault:
	force_sig(SIGSEGV, current);
	return 0;
	}