sys_ia32.c

上传linux-jx2410的源代码

#define ROUND_UP_TIME(x,y) (((x)+(y)-1)/(y))

asmlinkage long
sys32_select (int n, fd_set *inp, fd_set *outp, fd_set *exp, struct timeval32 *tvp32)
{
	fd_set_bits fds;
	char *bits;
	long timeout;
	int ret, size;

	timeout = MAX_SCHEDULE_TIMEOUT;
	if (tvp32) {
		time_t sec, usec;

		ret = -EFAULT;
		if (get_user(sec, &tvp32->tv_sec) || get_user(usec, &tvp32->tv_usec))
			goto out_nofds;

		ret = -EINVAL;
		if (sec < 0 || usec < 0)
			goto out_nofds;

		if ((unsigned long) sec < MAX_SELECT_SECONDS) {
			timeout = ROUND_UP_TIME(usec, 1000000/HZ);
			timeout += sec * (unsigned long) HZ;
		}
	}

	ret = -EINVAL;
	if (n < 0)
		goto out_nofds;

	if (n > current->files->max_fdset)
		n = current->files->max_fdset;

	/*
	 * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
	 * since we used fdset we need to allocate memory in units of
	 * long-words.
	 */
	ret = -ENOMEM;
	size = FDS_BYTES(n);
	bits = kmalloc(6 * size, GFP_KERNEL);
	if (!bits)
		goto out_nofds;
	fds.in      = (unsigned long *)  bits;
	fds.out     = (unsigned long *) (bits +   size);
	fds.ex      = (unsigned long *) (bits + 2*size);
	fds.res_in  = (unsigned long *) (bits + 3*size);
	fds.res_out = (unsigned long *) (bits + 4*size);
	fds.res_ex  = (unsigned long *) (bits + 5*size);

	if ((ret = get_fd_set(n, inp, fds.in)) ||
	    (ret = get_fd_set(n, outp, fds.out)) ||
	    (ret = get_fd_set(n, exp, fds.ex)))
		goto out;
	zero_fd_set(n, fds.res_in);
	zero_fd_set(n, fds.res_out);
	zero_fd_set(n, fds.res_ex);

	ret = do_select(n, &fds, &timeout);

	if (tvp32 && !(current->personality & STICKY_TIMEOUTS)) {
		time_t sec = 0, usec = 0;
		if (timeout) {
			sec = timeout / HZ;
			usec = timeout % HZ;
			usec *= (1000000/HZ);
		}
		if (put_user(sec, &tvp32->tv_sec) || put_user(usec, &tvp32->tv_usec)) {
			ret = -EFAULT;
			goto out;
		}
	}

	if (ret < 0)
		goto out;
	if (!ret) {
		ret = -ERESTARTNOHAND;
		if (signal_pending(current))
			goto out;
		ret = 0;
	}

	set_fd_set(n, inp, fds.res_in);
	set_fd_set(n, outp, fds.res_out);
	set_fd_set(n, exp, fds.res_ex);

out:
	kfree(bits);
out_nofds:
	return ret;
}

struct sel_arg_struct {
	unsigned int n;
	unsigned int inp;
	unsigned int outp;
	unsigned int exp;
	unsigned int tvp;
};

asmlinkage long
sys32_old_select (struct sel_arg_struct *arg)
{
	struct sel_arg_struct a;

	if (copy_from_user(&a, arg, sizeof(a)))
		return -EFAULT;
	return sys32_select(a.n, (fd_set *) A(a.inp), (fd_set *) A(a.outp), (fd_set *) A(a.exp),
			    (struct timeval32 *) A(a.tvp));
}

extern asmlinkage long sys_nanosleep (struct timespec *rqtp, struct timespec *rmtp);

asmlinkage long
sys32_nanosleep (struct timespec32 *rqtp, struct timespec32 *rmtp)
{
	struct timespec t;
	int ret;
	mm_segment_t old_fs = get_fs();

	if (get_user (t.tv_sec, &rqtp->tv_sec) || get_user (t.tv_nsec, &rqtp->tv_nsec))
		return -EFAULT;
	set_fs(KERNEL_DS);
	ret = sys_nanosleep(&t, rmtp ? &t : NULL);
	set_fs(old_fs);
	if (rmtp && ret == -EINTR) {
		if (put_user(t.tv_sec, &rmtp->tv_sec) || put_user(t.tv_nsec, &rmtp->tv_nsec))
			return -EFAULT;
	}
	return ret;
}

struct iovec32 { unsigned int iov_base; int iov_len; };
asmlinkage ssize_t sys_readv (unsigned long,const struct iovec *,unsigned long);
asmlinkage ssize_t sys_writev (unsigned long,const struct iovec *,unsigned long);

static struct iovec *
get_iovec32 (struct iovec32 *iov32, struct iovec *iov_buf, u32 count, int type)
{
	int i;
	u32 buf, len;
	struct iovec *ivp, *iov;

	/* Get the "struct iovec" from user memory */

	if (!count)
		return 0;
	if (verify_area(VERIFY_READ, iov32, sizeof(struct iovec32)*count))
		return NULL;
	if (count > UIO_MAXIOV)
		return NULL;
	if (count > UIO_FASTIOV) {
		iov = kmalloc(count*sizeof(struct iovec), GFP_KERNEL);
		if (!iov)
			return NULL;
	} else
		iov = iov_buf;

	ivp = iov;
	for (i = 0; i < count; i++) {
		if (__get_user(len, &iov32->iov_len) || __get_user(buf, &iov32->iov_base)) {
			if (iov != iov_buf)
				kfree(iov);
			return NULL;
		}
		if (verify_area(type, (void *)A(buf), len)) {
			if (iov != iov_buf)
				kfree(iov);
			return((struct iovec *)0);
		}
		ivp->iov_base = (void *)A(buf);
		ivp->iov_len = (__kernel_size_t) len;
		iov32++;
		ivp++;
	}
	return iov;
}

asmlinkage long
sys32_readv (int fd, struct iovec32 *vector, u32 count)
{
	struct iovec iovstack[UIO_FASTIOV];
	struct iovec *iov;
	long ret;
	mm_segment_t old_fs = get_fs();

	iov = get_iovec32(vector, iovstack, count, VERIFY_WRITE);
	if (!iov)
		return -EFAULT;
	set_fs(KERNEL_DS);
	ret = sys_readv(fd, iov, count);
	set_fs(old_fs);
	if (iov != iovstack)
		kfree(iov);
	return ret;
}

asmlinkage long
sys32_writev (int fd, struct iovec32 *vector, u32 count)
{
	struct iovec iovstack[UIO_FASTIOV];
	struct iovec *iov;
	long ret;
	mm_segment_t old_fs = get_fs();

	iov = get_iovec32(vector, iovstack, count, VERIFY_READ);
	if (!iov)
		return -EFAULT;
	set_fs(KERNEL_DS);
	ret = sys_writev(fd, iov, count);
	set_fs(old_fs);
	if (iov != iovstack)
		kfree(iov);
	return ret;
}

#define RLIM_INFINITY32	0x7fffffff
#define RESOURCE32(x) ((x > RLIM_INFINITY32) ? RLIM_INFINITY32 : x)

struct rlimit32 {
	int	rlim_cur;
	int	rlim_max;
};

extern asmlinkage long sys_getrlimit (unsigned int resource, struct rlimit *rlim);

asmlinkage long
sys32_old_getrlimit (unsigned int resource, struct rlimit32 *rlim)
{
	mm_segment_t old_fs = get_fs();
	struct rlimit r;
	int ret;

	set_fs(KERNEL_DS);
	ret = sys_getrlimit(resource, &r);
	set_fs(old_fs);
	if (!ret) {
		ret = put_user(RESOURCE32(r.rlim_cur), &rlim->rlim_cur);
		ret |= put_user(RESOURCE32(r.rlim_max), &rlim->rlim_max);
	}
	return ret;
}

asmlinkage long
sys32_getrlimit (unsigned int resource, struct rlimit32 *rlim)
{
	mm_segment_t old_fs = get_fs();
	struct rlimit r;
	int ret;

	set_fs(KERNEL_DS);
	ret = sys_getrlimit(resource, &r);
	set_fs(old_fs);
	if (!ret) {
		if (r.rlim_cur >= 0xffffffff)
			r.rlim_cur = 0xffffffff;
		if (r.rlim_max >= 0xffffffff)
			r.rlim_max = 0xffffffff;
		ret = put_user(r.rlim_cur, &rlim->rlim_cur);
		ret |= put_user(r.rlim_max, &rlim->rlim_max);
	}
	return ret;
}

extern asmlinkage long sys_setrlimit (unsigned int resource, struct rlimit *rlim);

asmlinkage long
sys32_setrlimit (unsigned int resource, struct rlimit32 *rlim)
{
	struct rlimit r;
	int ret;
	mm_segment_t old_fs = get_fs();

	if (resource >= RLIM_NLIMITS)
		return -EINVAL;
	if (get_user(r.rlim_cur, &rlim->rlim_cur) || get_user(r.rlim_max, &rlim->rlim_max))
		return -EFAULT;
	if (r.rlim_cur == RLIM_INFINITY32)
		r.rlim_cur = RLIM_INFINITY;
	if (r.rlim_max == RLIM_INFINITY32)
		r.rlim_max = RLIM_INFINITY;
	set_fs(KERNEL_DS);
	ret = sys_setrlimit(resource, &r);
	set_fs(old_fs);
	return ret;
}

/*
 *  Declare the IA32 version of the msghdr
 */

struct msghdr32 {
	unsigned int    msg_name;	/* Socket name			*/
	int		msg_namelen;	/* Length of name		*/
	unsigned int    msg_iov;	/* Data blocks			*/
	unsigned int	msg_iovlen;	/* Number of blocks		*/
	unsigned int    msg_control;	/* Per protocol magic (eg BSD file descriptor passing) */
	unsigned int	msg_controllen;	/* Length of cmsg list */
	unsigned	msg_flags;
};

struct cmsghdr32 {
	__kernel_size_t32 cmsg_len;
	int               cmsg_level;
	int               cmsg_type;
};

/* Bleech... */
#define __CMSG32_NXTHDR(ctl, len, cmsg, cmsglen) __cmsg32_nxthdr((ctl),(len),(cmsg),(cmsglen))
#define CMSG32_NXTHDR(mhdr, cmsg, cmsglen)	cmsg32_nxthdr((mhdr), (cmsg), (cmsglen))
#define CMSG32_ALIGN(len) ( ((len)+sizeof(int)-1) & ~(sizeof(int)-1) )
#define CMSG32_DATA(cmsg) \
	((void *)((char *)(cmsg) + CMSG32_ALIGN(sizeof(struct cmsghdr32))))
#define CMSG32_SPACE(len) \
	(CMSG32_ALIGN(sizeof(struct cmsghdr32)) + CMSG32_ALIGN(len))
#define CMSG32_LEN(len) (CMSG32_ALIGN(sizeof(struct cmsghdr32)) + (len))
#define __CMSG32_FIRSTHDR(ctl,len) \
	((len) >= sizeof(struct cmsghdr32) ? (struct cmsghdr32 *)(ctl) : (struct cmsghdr32 *)NULL)
#define CMSG32_FIRSTHDR(msg)	__CMSG32_FIRSTHDR((msg)->msg_control, (msg)->msg_controllen)

static inline struct cmsghdr32 *
__cmsg32_nxthdr (void *ctl, __kernel_size_t size, struct cmsghdr32 *cmsg, int cmsg_len)
{
	struct cmsghdr32 * ptr;

	ptr = (struct cmsghdr32 *)(((unsigned char *) cmsg) + CMSG32_ALIGN(cmsg_len));
	if ((unsigned long)((char*)(ptr+1) - (char *) ctl) > size)
		return NULL;
	return ptr;
}

static inline struct cmsghdr32 *
cmsg32_nxthdr (struct msghdr *msg, struct cmsghdr32 *cmsg, int cmsg_len)
{
	return __cmsg32_nxthdr(msg->msg_control, msg->msg_controllen, cmsg, cmsg_len);
}

static inline int
get_msghdr32 (struct msghdr *mp, struct msghdr32 *mp32)
{
	int ret;
	unsigned int i;

	if (!access_ok(VERIFY_READ, mp32, sizeof(*mp32)))
		return -EFAULT;
	ret = __get_user(i, &mp32->msg_name);
	mp->msg_name = (void *)A(i);
	ret |= __get_user(mp->msg_namelen, &mp32->msg_namelen);
	ret |= __get_user(i, &mp32->msg_iov);
	mp->msg_iov = (struct iovec *)A(i);
	ret |= __get_user(mp->msg_iovlen, &mp32->msg_iovlen);
	ret |= __get_user(i, &mp32->msg_control);
	mp->msg_control = (void *)A(i);
	ret |= __get_user(mp->msg_controllen, &mp32->msg_controllen);
	ret |= __get_user(mp->msg_flags, &mp32->msg_flags);
	return ret ? -EFAULT : 0;
}

/*
 * There is a lot of hair here because the alignment rules (and thus placement) of cmsg
 * headers and length are different for 32-bit apps.  -DaveM
 */
static int
get_cmsghdr32 (struct msghdr *kmsg, unsigned char *stackbuf, struct sock *sk, size_t *bufsize)
{
	struct cmsghdr *kcmsg, *kcmsg_base;
	__kernel_size_t kcmlen, tmp;
	__kernel_size_t32 ucmlen;
	struct cmsghdr32 *ucmsg;
	long err;

	kcmlen = 0;
	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
	ucmsg = CMSG32_FIRSTHDR(kmsg);
	while (ucmsg != NULL) {
		if (get_user(ucmlen, &ucmsg->cmsg_len))
			return -EFAULT;

		/* Catch bogons. */
		if (CMSG32_ALIGN(ucmlen) < CMSG32_ALIGN(sizeof(struct cmsghdr32)))
			return -EINVAL;
		if ((unsigned long)(((char *)ucmsg - (char *)kmsg->msg_control) + ucmlen)
		    > kmsg->msg_controllen)
			return -EINVAL;

		tmp = ((ucmlen - CMSG32_ALIGN(sizeof(*ucmsg))) +
		       CMSG_ALIGN(sizeof(struct cmsghdr)));
		kcmlen += tmp;
		ucmsg = CMSG32_NXTHDR(kmsg, ucmsg, ucmlen);
	}
	if (kcmlen == 0)
		return -EINVAL;

	/*
	 * The kcmlen holds the 64-bit version of the control length.  It may not be
	 * modified as we do not stick it into the kmsg until we have successfully copied
	 * over all of the data from the user.
	 */
	if (kcmlen > *bufsize) {
		*bufsize = kcmlen;
		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
	}
	if (kcmsg == NULL)
		return -ENOBUFS;

	/* Now copy them over neatly. */
	memset(kcmsg, 0, kcmlen);
	ucmsg = CMSG32_FIRSTHDR(kmsg);
	while (ucmsg != NULL) {
		err = get_user(ucmlen, &ucmsg->cmsg_len);
		tmp = ((ucmlen - CMSG32_ALIGN(sizeof(*ucmsg))) +
		       CMSG_ALIGN(sizeof(struct cmsghdr)));
		kcmsg->cmsg_len = tmp;
		err |= get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level);
		err |= get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type);

		/* Copy over the data. */
		err |= copy_from_user(CMSG_DATA(kcmsg), CMSG32_DATA(ucmsg),
				      (ucmlen - CMSG32_ALIGN(sizeof(*ucmsg))));
		if (err)
			goto out_free_efault;

		/* Advance. */
		kcmsg = (struct cmsghdr *)((char *)kcmsg + CMSG_ALIGN(tmp));
		ucmsg = CMSG32_NXTHDR(kmsg, ucmsg, ucmlen);
	}

	/* Ok, looks like we made it.  Hook it up and return success. */
	kmsg->msg_control = kcmsg_base;
	kmsg->msg_controllen = kcmlen;
	return 0;

out_free_efault:
	if (kcmsg_base != (struct cmsghdr *)stackbuf)
		sock_kfree_s(sk, kcmsg_base, kcmlen);
	return -EFAULT;
}

/*
 *	Verify & re-shape IA32 iovec. The caller must ensure that the
 *      iovec is big enough to hold the re-shaped message iovec.
 *
 *	Save time not doing verify_area. copy_*_user will make this work
 *	in any case.
 *
 *	Don't need to check the total size for overflow (cf net/core/iovec.c),
 *	32-bit sizes can't overflow a 64-bit count.
 */

static inline int
verify_iovec32 (struct msghdr *m, struct iovec *iov, char *address, int mode)
{
	int size, err, ct;
	struct iovec32 *iov32;

	if (m->msg_namelen) {
		if (mode == VERIFY_READ) {
			err = move_addr_to_kernel(m->msg_name, m->msg_namelen, address);
			if (err < 0)
				goto out;
		}
		m->msg_name = address;
	} else
		m->msg_name = NULL;

	err = -EFAULT;
	size = m->msg_iovlen * sizeof(struct iovec32);
	if (copy_from_user(iov, m->msg_iov, size))
		goto out;
	m->msg_iov = iov;

	err = 0;
	iov32 = (struct iovec32 *)iov;
	for (ct = m->msg_iovlen; ct-- > 0; ) {
		iov[ct].iov_len = (__kernel_size_t)iov32[ct].iov_len;
		iov[ct].iov_base = (void *) A(iov32[ct].iov_base);
		err += iov[ct].iov_len;
	}
out:
	return err;
}

static void
put_cmsg32(struct msghdr *kmsg, int level, int type, int len, void *data)
{
	struct cmsghdr32 *cm = (struct cmsghdr32 *) kmsg->msg_control;
	struct cmsghdr32 cmhdr;
	int cmlen = CMSG32_LEN(len);

	if(cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
		kmsg->msg_flags |= MSG_CTRUNC;
		return;
	}

	if(kmsg->msg_controllen < cmlen) {
		kmsg->msg_flags |= MSG_CTRUNC;
		cmlen = kmsg->msg_controllen;
	}
	cmhdr.cmsg_level = level;
	cmhdr.cmsg_type = type;
	cmhdr.cmsg_len = cmlen;