sys_ia32.c

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	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;
}

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;
};

static inline int
shape_msg(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);
}

/*
 *	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;
}

extern __inline__ void
sockfd_put(struct socket *sock)
{
	fput(sock->file);
}

/* XXX This really belongs in some header file... -DaveM */
#define MAX_SOCK_ADDR	128		/* 108 for Unix domain - 
					   16 for IP, 16 for IPX,
					   24 for IPv6,
					   about 80 for AX.25 */

extern struct socket *sockfd_lookup(int fd, int *err);

/*
 *	BSD sendmsg interface
 */

int sys32_sendmsg(int fd, struct msghdr32 *msg, unsigned flags)
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
	unsigned char ctl[sizeof(struct cmsghdr) + 20];	/* 20 is size of ipv6_pktinfo */
	unsigned char *ctl_buf = ctl;
	struct msghdr msg_sys;
	int err, ctl_len, iov_size, total_len;
	
	err = -EFAULT;
	if (shape_msg(&msg_sys, msg))
		goto out; 

	sock = sockfd_lookup(fd, &err);
	if (!sock) 
		goto out;

	/* do not move before msg_sys is valid */
	err = -EINVAL;
	if (msg_sys.msg_iovlen > UIO_MAXIOV)
		goto out_put;

	/* Check whether to allocate the iovec area*/
	err = -ENOMEM;
	iov_size = msg_sys.msg_iovlen * sizeof(struct iovec32);
	if (msg_sys.msg_iovlen > UIO_FASTIOV) {
		iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
		if (!iov)
			goto out_put;
	}

	/* This will also move the address data into kernel space */
	err = verify_iovec32(&msg_sys, iov, address, VERIFY_READ);
	if (err < 0) 
		goto out_freeiov;
	total_len = err;

	err = -ENOBUFS;

	if (msg_sys.msg_controllen > INT_MAX)
		goto out_freeiov;
	ctl_len = msg_sys.msg_controllen; 
	if (ctl_len) 
	{
		if (ctl_len > sizeof(ctl))
		{
			err = -ENOBUFS;
			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
			if (ctl_buf == NULL) 
				goto out_freeiov;
		}
		err = -EFAULT;
		if (copy_from_user(ctl_buf, msg_sys.msg_control, ctl_len))
			goto out_freectl;
		msg_sys.msg_control = ctl_buf;
	}
	msg_sys.msg_flags = flags;

	if (sock->file->f_flags & O_NONBLOCK)
		msg_sys.msg_flags |= MSG_DONTWAIT;
	err = sock_sendmsg(sock, &msg_sys, total_len);

out_freectl:
	if (ctl_buf != ctl)    
		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
out_freeiov:
	if (iov != iovstack)
		sock_kfree_s(sock->sk, iov, iov_size);
out_put:
	sockfd_put(sock);
out:       
	return err;
}

/*
 *	BSD recvmsg interface
 */

int
sys32_recvmsg (int fd, struct msghdr32 *msg, unsigned int flags)
{
	struct socket *sock;
	struct iovec iovstack[UIO_FASTIOV];
	struct iovec *iov=iovstack;
	struct msghdr msg_sys;
	unsigned long cmsg_ptr;
	int err, iov_size, total_len, len;

	/* kernel mode address */
	char addr[MAX_SOCK_ADDR];

	/* user mode address pointers */
	struct sockaddr *uaddr;
	int *uaddr_len;
	
	err=-EFAULT;
	if (shape_msg(&msg_sys, msg))
		goto out;

	sock = sockfd_lookup(fd, &err);
	if (!sock)
		goto out;

	err = -EINVAL;
	if (msg_sys.msg_iovlen > UIO_MAXIOV)
		goto out_put;
	
	/* Check whether to allocate the iovec area*/
	err = -ENOMEM;
	iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
	if (msg_sys.msg_iovlen > UIO_FASTIOV) {
		iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
		if (!iov)
			goto out_put;
	}

	/*
	 *	Save the user-mode address (verify_iovec will change the
	 *	kernel msghdr to use the kernel address space)
	 */
	 
	uaddr = msg_sys.msg_name;
	uaddr_len = &msg->msg_namelen;
	err = verify_iovec32(&msg_sys, iov, addr, VERIFY_WRITE);
	if (err < 0)
		goto out_freeiov;
	total_len=err;

	cmsg_ptr = (unsigned long)msg_sys.msg_control;
	msg_sys.msg_flags = 0;
	
	if (sock->file->f_flags & O_NONBLOCK)
		flags |= MSG_DONTWAIT;
	err = sock_recvmsg(sock, &msg_sys, total_len, flags);
	if (err < 0)
		goto out_freeiov;
	len = err;

	if (uaddr != NULL) {
		err = move_addr_to_user(addr, msg_sys.msg_namelen, uaddr, uaddr_len);
		if (err < 0)
			goto out_freeiov;
	}
	err = __put_user(msg_sys.msg_flags, &msg->msg_flags);
	if (err)
		goto out_freeiov;
	err = __put_user((unsigned long)msg_sys.msg_control-cmsg_ptr, 
							 &msg->msg_controllen);
	if (err)
		goto out_freeiov;
	err = len;

out_freeiov:
	if (iov != iovstack)
		sock_kfree_s(sock->sk, iov, iov_size);
out_put:
	sockfd_put(sock);
out:
	return err;
}

/* Argument list sizes for sys_socketcall */
#define AL(x) ((x) * sizeof(u32))
static unsigned char nas[18]={AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
                                AL(3),AL(3),AL(4),AL(4),AL(4),AL(6),
                                AL(6),AL(2),AL(5),AL(5),AL(3),AL(3)};
#undef AL

extern asmlinkage long sys_bind(int fd, struct sockaddr *umyaddr, int addrlen);
extern asmlinkage long sys_connect(int fd, struct sockaddr *uservaddr,
				  int addrlen);
extern asmlinkage long sys_accept(int fd, struct sockaddr *upeer_sockaddr,
				 int *upeer_addrlen); 
extern asmlinkage long sys_getsockname(int fd, struct sockaddr *usockaddr,
				      int *usockaddr_len);
extern asmlinkage long sys_getpeername(int fd, struct sockaddr *usockaddr,
				      int *usockaddr_len);
extern asmlinkage long sys_send(int fd, void *buff, size_t len, unsigned flags);
extern asmlinkage long sys_sendto(int fd, u32 buff, __kernel_size_t32 len,
				   unsigned flags, u32 addr, int addr_len);
extern asmlinkage long sys_recv(int fd, void *ubuf, size_t size, unsigned flags);
extern asmlinkage long sys_recvfrom(int fd, u32 ubuf, __kernel_size_t32 size,
				     unsigned flags, u32 addr, u32 addr_len);
extern asmlinkage long sys_setsockopt(int fd, int level, int optname,
				     char *optval, int optlen);
extern asmlinkage long sys_getsockopt(int fd, int level, int optname,
				       u32 optval, u32 optlen);

extern asmlinkage long sys_socket(int family, int type, int protocol);
extern asmlinkage long sys_socketpair(int family, int type, int protocol,
				     int usockvec[2]);
extern asmlinkage long sys_shutdown(int fd, int how);
extern asmlinkage long sys_listen(int fd, int backlog);

asmlinkage long sys32_socketcall(int call, u32 *args)
{
	int ret;
	u32 a[6];
	u32 a0,a1;
				 
	if (call<SYS_SOCKET||call>SYS_RECVMSG)
		return -EINVAL;
	if (copy_from_user(a, args, nas[call]))
		return -EFAULT;
	a0=a[0];
	a1=a[1];
	
	switch(call) 
	{
		case SYS_SOCKET:
			ret = sys_socket(a0, a1, a[2]);
			break;
		case SYS_BIND:
			ret = sys_bind(a0, (struct sockaddr *)A(a1), a[2]);
			break;
		case SYS_CONNECT:
			ret = sys_connect(a0, (struct sockaddr *)A(a1), a[2]);
			break;
		case SYS_LISTEN:
			ret = sys_listen(a0, a1);
			break;
		case SYS_ACCEPT:
			ret = sys_accept(a0, (struct sockaddr *)A(a1),
					  (int *)A(a[2]));
			break;
		case SYS_GETSOCKNAME:
			ret = sys_getsockname(a0, (struct sockaddr *)A(a1),
					       (int *)A(a[2]));
			break;
		case SYS_GETPEERNAME:
			ret = sys_getpeername(a0, (struct sockaddr *)A(a1),
					       (int *)A(a[2]));
			break;
		case SYS_SOCKETPAIR:
			ret = sys_socketpair(a0, a1, a[2], (int *)A(a[3]));
			break;
		case SYS_SEND:
			ret = sys_send(a0, (void *)A(a1), a[2], a[3]);
			break;
		case SYS_SENDTO:
			ret = sys_sendto(a0, a1, a[2], a[3], a[4], a[5]);
			break;
		case SYS_RECV:
			ret = sys_recv(a0, (void *)A(a1), a[2], a[3]);
			break;
		case SYS_RECVFROM:
			ret = sys_recvfrom(a0, a1, a[2], a[3], a[4], a[5]);
			break;
		case SYS_SHUTDOWN:
			ret = sys_shutdown(a0,a1);
			break;
		case SYS_SETSOCKOPT:
			ret = sys_setsockopt(a0, a1, a[2], (char *)A(a[3]),
					      a[4]);
			break;
		case SYS_GETSOCKOPT:
			ret = sys_getsockopt(a0, a1, a[2], a[3], a[4]);
			break;
		case SYS_SENDMSG:
			ret = sys32_sendmsg(a0, (struct msghdr32 *)A(a1),
					     a[2]);
			break;
		case SYS_RECVMSG:
			ret = sys32_recvmsg(a0, (struct msghdr32 *)A(a1),
					     a[2]);
			break;
		default:
			ret = EINVAL;
			break;
	}
	return ret;
}

/*
 * sys32_ipc() is the de-multiplexer for the SysV IPC calls in 32bit emulation..
 *
 * This is really horribly ugly.
 */

struct msgbuf32 { s32 mtype; char mtext[1]; };

struct ipc_perm32
{
	key_t    	  key;
        __kernel_uid_t32  uid;
        __kernel_gid_t32  gid;
        __kernel_uid_t32  cuid;
        __kernel_gid_t32  cgid;
        __kernel_mode_t32 mode;
        unsigned short  seq;
};

struct semid_ds32 {
        struct ipc_perm32 sem_perm;               /* permissions .. see ipc.h */
        __kernel_time_t32 sem_otime;              /* last semop time */
        __kernel_time_t32 sem_ctime;              /* last change time */
        u32 sem_base;              /* ptr to first semaphore in array */
        u32 sem_pending;          /* pending operations to be processed */
        u32 sem_pending_last;    /* last pending operation */
        u32 undo;                  /* undo requests on this array */
        unsigned short  sem_nsems;              /* no. of semaphores in array */
};

struct msqid_ds32
{
        struct ipc_perm32 msg_perm;
        u32 msg_first;
        u32 msg_last;
        __kernel_time_t32 msg_stime;
        __kernel_time_t32 msg_rtime;
        __kernel_time_t32 msg_ctime;
        u32 wwait;
        u32 rwait;
        unsigned short msg_cbytes;
        unsigned short msg_qnum;  
        unsigned short msg_qbytes;
        __kernel_ipc_pid_t32 msg_lspid;
        __kernel_ipc_pid_t32 msg_lrpid;
};

struct shmid_ds32 {
        struct ipc_perm32       shm_perm;
        int                     shm_segsz;
        __kernel_time_t32       shm_atime;
        __kernel_time_t32       shm_dtime;
        __kernel_time_t32       shm_ctime;
        __kernel_ipc_pid_t32    shm_cpid; 
        __kernel_ipc_pid_t32    shm_lpid; 
        unsigned short          shm_nattch;
};

#define IPCOP_MASK(__x)	(1UL << (__x))

static int
do_sys32_semctl(int first, int second, int third, void *uptr)
{
	union semun fourth;
	u32 pad;
	int err, err2;
	struct semid64_ds s;
	struct semid_ds32 *usp;
	mm_segment_t old_fs;

	if (!uptr)
		return -EINVAL;
	err = -EFAULT;
	if (get_user (pad, (u32 *)uptr))
		return err;
	if(third == SETVAL)
		fourth.val = (int)pad;
	else
		fourth.__pad = (void *)A(pad);
	switch (third) {

	case IPC_INFO:
	case IPC_RMID:
	case IPC_SET:
	case SEM_INFO:
	case GETVAL:
	case GETPID:
	case GETNCNT:
	case GETZCNT:
	case GETALL:
	case SETVAL:
	case SETALL:
		err = sys_semctl (first, second, third, fourth);
		break;

	case IPC_STAT:
	case SEM_STAT:
		usp = (struct semid_ds32 *)A(pad);
		fourth.__pad = &s;
		old_fs = get_fs ();
		set_fs (KERNEL_DS);
		err = sys_semctl (first, second, third, fourth);
		set_fs (old_fs);
		err2 = put_user(s.sem_perm.key, &usp->sem_perm.key);
		err2 |= __put_user(s.sem_perm.uid, &usp->sem_perm.uid);
		err2 |= __put_user(s.sem_perm.gid, &usp->sem_perm.gid);
		err2 |= __put_user(s.sem_perm.cuid,
				   &usp->sem_perm.cuid);
		err2 |= __put_user (s.sem_perm.cgid,
				    &usp->sem_perm.cgid);
		err2 |= __put_user (s.sem_perm.mode,
				    &usp->sem_perm.mode);
		err2 |= __put_user (s.sem_perm.seq, &usp->sem_perm.seq);
		err2 |= __put_user (s.sem_otime, &usp->sem_otime);
		err2 |= __put_user (s.sem_ctime, &usp->sem_ctime);
		err2 |= __put_user (s.sem_nsems, &usp->sem_nsems);
		if (err2)
			err = -EFAULT;
		break;

	}

	return err;
}

static int
do_sys32_msgsnd (int first, int second, int third, void *uptr)
{
	struct msgbuf *p = kmalloc (second + sizeof (struct msgbuf)