ia32_signal.c

广州斯道2410普及版II的源代码

/*
 * IA32 Architecture-specific signal handling support.
 *
 * Copyright (C) 1999, 2001 Hewlett-Packard Co
 *	David Mosberger-Tang <[e-mail]>
 * Copyright (C) 1999 Arun Sharma <[e-mail]>
 * Copyright (C) 2000 VA Linux Co
 * Copyright (C) 2000 Don Dugger <[e-mail]>
 *
 * Derived from i386 and Alpha versions.
 */

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/wait.h>

#include <asm/uaccess.h>
#include <asm/rse.h>
#include <asm/sigcontext.h>
#include <asm/segment.h>
#include <asm/ia32.h>

#include "../kernel/sigframe.h"

#define A(__x)		((unsigned long)(__x))

#define DEBUG_SIG	0
#define _BLOCKABLE	(~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

#define __IA32_NR_sigreturn            119
#define __IA32_NR_rt_sigreturn         173

struct sigframe_ia32
{
       int pretcode;
       int sig;
       struct sigcontext_ia32 sc;
       struct _fpstate_ia32 fpstate;
       unsigned int extramask[_IA32_NSIG_WORDS-1];
       char retcode[8];
};

struct rt_sigframe_ia32
{
       int pretcode;
       int sig;
       int pinfo;
       int puc;
       siginfo_t32 info;
       struct ucontext_ia32 uc;
       struct _fpstate_ia32 fpstate;
       char retcode[8];
};

int
copy_siginfo_from_user32 (siginfo_t *to, siginfo_t32 *from)
{
	unsigned long tmp;
	int err;

	if (!access_ok(VERIFY_READ, from, sizeof(siginfo_t32)))
		return -EFAULT;

	err = __get_user(to->si_signo, &from->si_signo);
	err |= __get_user(to->si_errno, &from->si_errno);
	err |= __get_user(to->si_code, &from->si_code);

	if (from->si_code < 0)
		err |= __copy_from_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
	else {
		switch (from->si_code >> 16) {
		      case __SI_CHLD >> 16:
			err |= __get_user(to->si_utime, &from->si_utime);
			err |= __get_user(to->si_stime, &from->si_stime);
			err |= __get_user(to->si_status, &from->si_status);
		      default:
			err |= __get_user(to->si_pid, &from->si_pid);
			err |= __get_user(to->si_uid, &from->si_uid);
			break;
		      case __SI_FAULT >> 16:
			err |= __get_user(tmp, &from->si_addr);
			to->si_addr = (void *) tmp;
			break;
		      case __SI_POLL >> 16:
			err |= __get_user(to->si_band, &from->si_band);
			err |= __get_user(to->si_fd, &from->si_fd);
			break;
			/* case __SI_RT: This is not generated by the kernel as of now.  */
		}
	}
	return err;
}

int
copy_siginfo_to_user32 (siginfo_t32 *to, siginfo_t *from)
{
	int err;

	if (!access_ok(VERIFY_WRITE, to, sizeof(siginfo_t32)))
		return -EFAULT;

	/* If you change siginfo_t structure, please be sure
	   this code is fixed accordingly.
	   It should never copy any pad contained in the structure
	   to avoid security leaks, but must copy the generic
	   3 ints plus the relevant union member.
	   This routine must convert siginfo from 64bit to 32bit as well
	   at the same time.  */
	err = __put_user(from->si_signo, &to->si_signo);
	err |= __put_user(from->si_errno, &to->si_errno);
	err |= __put_user((short)from->si_code, &to->si_code);
	if (from->si_code < 0)
		err |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
	else {
		switch (from->si_code >> 16) {
		case __SI_CHLD >> 16:
			err |= __put_user(from->si_utime, &to->si_utime);
			err |= __put_user(from->si_stime, &to->si_stime);
			err |= __put_user(from->si_status, &to->si_status);
		default:
			err |= __put_user(from->si_pid, &to->si_pid);
			err |= __put_user(from->si_uid, &to->si_uid);
			break;
		case __SI_FAULT >> 16:
			err |= __put_user((long)from->si_addr, &to->si_addr);
			break;
		case __SI_POLL >> 16:
			err |= __put_user(from->si_band, &to->si_band);
			err |= __put_user(from->si_fd, &to->si_fd);
			break;
		/* case __SI_RT: This is not generated by the kernel as of now.  */
		}
	}
	return err;
}

static inline void
sigact_set_handler (struct k_sigaction *sa, unsigned int handler, unsigned int restorer)
{
	if (handler + 1 <= 2)
		/* SIG_DFL, SIG_IGN, or SIG_ERR: must sign-extend to 64-bits */
		sa->sa.sa_handler = (__sighandler_t) A((int) handler);
	else
		sa->sa.sa_handler = (__sighandler_t) (((unsigned long) restorer << 32) | handler);
}

asmlinkage long
ia32_rt_sigsuspend (sigset32_t *uset, unsigned int sigsetsize, struct sigscratch *scr)
{
	extern long ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall);
	sigset_t oldset, set;

	scr->scratch_unat = 0;	/* avoid leaking kernel bits to user level */
	memset(&set, 0, sizeof(&set));

	if (sigsetsize > sizeof(sigset_t))
		return -EINVAL;

	if (copy_from_user(&set.sig, &uset->sig, sigsetsize))
		return -EFAULT;

	sigdelsetmask(&set, ~_BLOCKABLE);

	spin_lock_irq(&current->sigmask_lock);
	{
		oldset = current->blocked;
		current->blocked = set;
		recalc_sigpending(current);
	}
	spin_unlock_irq(&current->sigmask_lock);

	/*
	 * The return below usually returns to the signal handler.  We need to pre-set the
	 * correct error code here to ensure that the right values get saved in sigcontext
	 * by ia64_do_signal.
	 */
	scr->pt.r8 = -EINTR;
	while (1) {
		current->state = TASK_INTERRUPTIBLE;
		schedule();
		if (ia64_do_signal(&oldset, scr, 1))
			return -EINTR;
	}
}

asmlinkage long
ia32_sigsuspend (unsigned int mask, struct sigscratch *scr)
{
	return ia32_rt_sigsuspend((sigset32_t *)&mask, sizeof(mask), scr);
}

asmlinkage long
sys32_signal (int sig, unsigned int handler)
{
	struct k_sigaction new_sa, old_sa;
	int ret;

	sigact_set_handler(&new_sa, handler, 0);
	new_sa.sa.sa_flags = SA_ONESHOT | SA_NOMASK;

	ret = do_sigaction(sig, &new_sa, &old_sa);

	return ret ? ret : IA32_SA_HANDLER(&old_sa);
}

asmlinkage long
sys32_rt_sigaction (int sig, struct sigaction32 *act,
		    struct sigaction32 *oact, unsigned int sigsetsize)
{
	struct k_sigaction new_ka, old_ka;
	unsigned int handler, restorer;
	int ret;

	/* XXX: Don't preclude handling different sized sigset_t's.  */
	if (sigsetsize != sizeof(sigset32_t))
		return -EINVAL;

	if (act) {
		ret = get_user(handler, &act->sa_handler);
		ret |= get_user(new_ka.sa.sa_flags, &act->sa_flags);
		ret |= get_user(restorer, &act->sa_restorer);
		ret |= copy_from_user(&new_ka.sa.sa_mask, &act->sa_mask, sizeof(sigset32_t));
		if (ret)
			return -EFAULT;

		sigact_set_handler(&new_ka, handler, restorer);
	}

	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

	if (!ret && oact) {
		ret = put_user(IA32_SA_HANDLER(&old_ka), &oact->sa_handler);
		ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags);
		ret |= put_user(IA32_SA_RESTORER(&old_ka), &oact->sa_restorer);
		ret |= copy_to_user(&oact->sa_mask, &old_ka.sa.sa_mask, sizeof(sigset32_t));
	}
	return ret;
}


extern asmlinkage long sys_rt_sigprocmask (int how, sigset_t *set, sigset_t *oset,
					   size_t sigsetsize);

asmlinkage long
sys32_rt_sigprocmask (int how, sigset32_t *set, sigset32_t *oset, unsigned int sigsetsize)
{
	mm_segment_t old_fs = get_fs();
	sigset_t s;
	long ret;

	if (sigsetsize > sizeof(s))
		return -EINVAL;

	if (set) {
		memset(&s, 0, sizeof(s));
		if (copy_from_user(&s.sig, set, sigsetsize))
			return -EFAULT;
	}
	set_fs(KERNEL_DS);
	ret = sys_rt_sigprocmask(how, set ? &s : NULL, oset ? &s : NULL, sizeof(s));
	set_fs(old_fs);
	if (ret)
		return ret;
	if (oset) {
		if (copy_to_user(oset, &s.sig, sigsetsize))
			return -EFAULT;
	}
	return 0;
}

asmlinkage long
sys32_sigprocmask (int how, unsigned int *set, unsigned int *oset)
{
	return sys32_rt_sigprocmask(how, (sigset32_t *) set, (sigset32_t *) oset, sizeof(*set));
}

asmlinkage long
sys32_rt_sigtimedwait (sigset32_t *uthese, siginfo_t32 *uinfo, struct timespec32 *uts,
		       unsigned int sigsetsize)
{
	extern asmlinkage long sys_rt_sigtimedwait (const sigset_t *, siginfo_t *,
						    const struct timespec *, size_t);
	extern int copy_siginfo_to_user32 (siginfo_t32 *, siginfo_t *);
	mm_segment_t old_fs = get_fs();
	struct timespec t;
	siginfo_t info;
	sigset_t s;
	int ret;

	if (copy_from_user(&s.sig, uthese, sizeof(sigset32_t)))
		return -EFAULT;
	if (uts) {
		ret = get_user(t.tv_sec, &uts->tv_sec);
		ret |= get_user(t.tv_nsec, &uts->tv_nsec);
		if (ret)
			return -EFAULT;
	}
	set_fs(KERNEL_DS);
	ret = sys_rt_sigtimedwait(&s, &info, &t, sigsetsize);
	set_fs(old_fs);
	if (ret >= 0 && uinfo) {
		if (copy_siginfo_to_user32(uinfo, &info))
			return -EFAULT;
	}
	return ret;
}

asmlinkage long
sys32_rt_sigqueueinfo (int pid, int sig, siginfo_t32 *uinfo)
{
	extern asmlinkage long sys_rt_sigqueueinfo (int, int, siginfo_t *);
	extern int copy_siginfo_from_user32 (siginfo_t *to, siginfo_t32 *from);
	mm_segment_t old_fs = get_fs();
	siginfo_t info;
	int ret;

	if (copy_siginfo_from_user32(&info, uinfo))
		return -EFAULT;
	set_fs(KERNEL_DS);
	ret = sys_rt_sigqueueinfo(pid, sig, &info);
	set_fs(old_fs);
	return ret;
}

asmlinkage long
sys32_sigaction (int sig, struct old_sigaction32 *act, struct old_sigaction32 *oact)
{
	struct k_sigaction new_ka, old_ka;
	unsigned int handler, restorer;
	int ret;

	if (act) {
		old_sigset32_t mask;

		ret = get_user(handler, &act->sa_handler);
		ret |= get_user(new_ka.sa.sa_flags, &act->sa_flags);
		ret |= get_user(restorer, &act->sa_restorer);
		ret |= get_user(mask, &act->sa_mask);
		if (ret)
			return ret;

		sigact_set_handler(&new_ka, handler, restorer);
		siginitset(&new_ka.sa.sa_mask, mask);
	}

	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

	if (!ret && oact) {
		ret = put_user(IA32_SA_HANDLER(&old_ka), &oact->sa_handler);
		ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags);
		ret |= put_user(IA32_SA_RESTORER(&old_ka), &oact->sa_restorer);
		ret |= put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
	}

	return ret;
}

static int
setup_sigcontext_ia32 (struct sigcontext_ia32 *sc, struct _fpstate_ia32 *fpstate,
		       struct pt_regs *regs, unsigned long mask)
{
	int  err = 0;
	unsigned long flag;