/*
 * 32bit Socket syscall emulation. Based on arch/sparc64/kernel/sys_sparc32.c.
 *
 * Copyright (C) 2000           VA Linux Co
 * Copyright (C) 2000           Don Dugger <n0ano@valinux.com>
 * Copyright (C) 1999           Arun Sharma <arun.sharma@intel.com>
 * Copyright (C) 1997,1998      Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 * Copyright (C) 1997           David S. Miller (davem@caip.rutgers.edu)
 * Copyright (C) 2000           Hewlett-Packard Co.
 * Copyright (C) 2000           David Mosberger-Tang <davidm@hpl.hp.com>
 * Copyright (C) 2000,2001      Andi Kleen, SuSE Labs
 */

#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/file.h>
#include <linux/icmpv6.h>
#include <linux/socket.h>
#include <linux/syscalls.h>
#include <linux/filter.h>
#include <linux/compat.h>
#include <linux/security.h>
#include <linux/audit.h>
#include <linux/export.h>

#include <net/scm.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <linux/uaccess.h>
#include <net/compat.h>

int get_compat_msghdr(struct msghdr *kmsg,
                      struct compat_msghdr __user *umsg,
                      struct sockaddr __user **save_addr,
                      struct iovec **iov)
{
        struct compat_msghdr msg;
        ssize_t err;

        if (copy_from_user(&msg, umsg, sizeof(*umsg)))
                return -EFAULT;

        kmsg->msg_flags = msg.msg_flags;
        kmsg->msg_namelen = msg.msg_namelen;

        if (!msg.msg_name)
                kmsg->msg_namelen = 0;

        if (kmsg->msg_namelen < 0)
                return -EINVAL;

        if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
                kmsg->msg_namelen = sizeof(struct sockaddr_storage);

        kmsg->msg_control = compat_ptr(msg.msg_control);
        kmsg->msg_controllen = msg.msg_controllen;

        if (save_addr)
                *save_addr = compat_ptr(msg.msg_name);

        if (msg.msg_name && kmsg->msg_namelen) {
                if (!save_addr) {
                        err = move_addr_to_kernel(compat_ptr(msg.msg_name),
                                                  kmsg->msg_namelen,
                                                  kmsg->msg_name);
                        if (err < 0)
                                return err;
                }
        } else {
                kmsg->msg_name = NULL;
                kmsg->msg_namelen = 0;
        }

        if (msg.msg_iovlen > UIO_MAXIOV)
                return -EMSGSIZE;

        kmsg->msg_iocb = NULL;

        return compat_import_iovec(save_addr ? READ : WRITE,
                                   compat_ptr(msg.msg_iov), msg.msg_iovlen,
                                   UIO_FASTIOV, iov, &kmsg->msg_iter);
}

/* Bleech... */
#define CMSG_COMPAT_ALIGN(len)  ALIGN((len), sizeof(s32))

#define CMSG_COMPAT_DATA(cmsg)                          \
        ((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr)))
#define CMSG_COMPAT_SPACE(len)                          \
        (sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len))
#define CMSG_COMPAT_LEN(len)                            \
        (sizeof(struct compat_cmsghdr) + (len))

#define CMSG_COMPAT_FIRSTHDR(msg)                       \
        (((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ?     \
         (struct compat_cmsghdr __user *)((msg)->msg_control) :         \
         (struct compat_cmsghdr __user *)NULL)

#define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
        ((ucmlen) >= sizeof(struct compat_cmsghdr) && \
         (ucmlen) <= (unsigned long) \
         ((mhdr)->msg_controllen - \
          ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))

static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
                struct compat_cmsghdr __user *cmsg, int cmsg_len)
{
        char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
        if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
                        msg->msg_controllen)
                return NULL;
        return (struct compat_cmsghdr __user *)ptr;
}

/* 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
 */
int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
                               unsigned char *stackbuf, int stackbuf_size)
{
        struct compat_cmsghdr __user *ucmsg;
        struct cmsghdr *kcmsg, *kcmsg_base;
        compat_size_t ucmlen;
        __kernel_size_t kcmlen, tmp;
        int err = -EFAULT;

        BUILD_BUG_ON(sizeof(struct compat_cmsghdr) !=
                     CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)));

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

                /* Catch bogons. */
                if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
                        return -EINVAL;

                tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
                tmp = CMSG_ALIGN(tmp);
                kcmlen += tmp;
                ucmsg = cmsg_compat_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 > stackbuf_size)
                kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
        if (kcmsg == NULL)
                return -ENOBUFS;

        /* Now copy them over neatly. */
        memset(kcmsg, 0, kcmlen);
        ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
        while (ucmsg != NULL) {
                if (__get_user(ucmlen, &ucmsg->cmsg_len))
                        goto Efault;
                if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
                        goto Einval;
                tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
                if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
                        goto Einval;
                kcmsg->cmsg_len = tmp;
                tmp = CMSG_ALIGN(tmp);
                if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
                    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
                    copy_from_user(CMSG_DATA(kcmsg),
                                   CMSG_COMPAT_DATA(ucmsg),
                                   (ucmlen - sizeof(*ucmsg))))
                        goto Efault;

                /* Advance. */
                kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
                ucmsg = cmsg_compat_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;

Einval:
        err = -EINVAL;
Efault:
        if (kcmsg_base != (struct cmsghdr *)stackbuf)
                sock_kfree_s(sk, kcmsg_base, kcmlen);
        return err;
}

int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
{
        struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
        struct compat_cmsghdr cmhdr;
        struct compat_timeval ctv;
        struct compat_timespec cts[3];
        int cmlen;

        if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
                kmsg->msg_flags |= MSG_CTRUNC;
                return 0; /* XXX: return error? check spec. */
        }

        if (!COMPAT_USE_64BIT_TIME) {
                if (level == SOL_SOCKET && type == SCM_TIMESTAMP) {
                        struct timeval *tv = (struct timeval *)data;
                        ctv.tv_sec = tv->tv_sec;
                        ctv.tv_usec = tv->tv_usec;
                        data = &ctv;
                        len = sizeof(ctv);
                }
                if (level == SOL_SOCKET &&
                    (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) {
                        int count = type == SCM_TIMESTAMPNS ? 1 : 3;
                        int i;
                        struct timespec *ts = (struct timespec *)data;
                        for (i = 0; i < count; i++) {
                                cts[i].tv_sec = ts[i].tv_sec;
                                cts[i].tv_nsec = ts[i].tv_nsec;
                        }
                        data = &cts;
                        len = sizeof(cts[0]) * count;
                }
        }

        cmlen = CMSG_COMPAT_LEN(len);
        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;

        if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
                return -EFAULT;
        if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
                return -EFAULT;
        cmlen = CMSG_COMPAT_SPACE(len);
        if (kmsg->msg_controllen < cmlen)
                cmlen = kmsg->msg_controllen;
        kmsg->msg_control += cmlen;
        kmsg->msg_controllen -= cmlen;
        return 0;
}

void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
{
        struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
        int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
        int fdnum = scm->fp->count;
        struct file **fp = scm->fp->fp;
        int __user *cmfptr;
        int err = 0, i;

        if (fdnum < fdmax)
                fdmax = fdnum;

        for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
                int new_fd;
                err = security_file_receive(fp[i]);
                if (err)
                        break;
                err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
                                          ? O_CLOEXEC : 0);
                if (err < 0)
                        break;
                new_fd = err;
                err = put_user(new_fd, cmfptr);
                if (err) {
                        put_unused_fd(new_fd);
                        break;
                }
                /* Bump the usage count and install the file. */
                fd_install(new_fd, get_file(fp[i]));
        }

        if (i > 0) {
                int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
                err = put_user(SOL_SOCKET, &cm->cmsg_level);
                if (!err)
                        err = put_user(SCM_RIGHTS, &cm->cmsg_type);
                if (!err)
                        err = put_user(cmlen, &cm->cmsg_len);
                if (!err) {
                        cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
                        kmsg->msg_control += cmlen;
                        kmsg->msg_controllen -= cmlen;
                }
        }
        if (i < fdnum)
                kmsg->msg_flags |= MSG_CTRUNC;

        /*
         * All of the files that fit in the message have had their
         * usage counts incremented, so we just free the list.
         */
        __scm_destroy(scm);
}

/* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */
struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval)
{
        struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
        struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
        struct compat_sock_fprog f32;
        struct sock_fprog f;

        if (copy_from_user(&f32, fprog32, sizeof(*fprog32)))
                return NULL;
        memset(&f, 0, sizeof(f));
        f.len = f32.len;
        f.filter = compat_ptr(f32.filter);
        if (copy_to_user(kfprog, &f, sizeof(struct sock_fprog)))
                return NULL;

        return kfprog;
}
EXPORT_SYMBOL_GPL(get_compat_bpf_fprog);

static int do_set_attach_filter(struct socket *sock, int level, int optname,
                                char __user *optval, unsigned int optlen)
{
        struct sock_fprog __user *kfprog;

        kfprog = get_compat_bpf_fprog(optval);
        if (!kfprog)
                return -EFAULT;

        return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
                              sizeof(struct sock_fprog));
}

static int do_set_sock_timeout(struct socket *sock, int level,
                int optname, char __user *optval, unsigned int optlen)
{
        struct compat_timeval __user *up = (struct compat_timeval __user *)optval;
        struct timeval ktime;
        mm_segment_t old_fs;
        int err;

        if (optlen < sizeof(*up))
                return -EINVAL;
        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
            __get_user(ktime.tv_sec, &up->tv_sec) ||
            __get_user(ktime.tv_usec, &up->tv_usec))
                return -EFAULT;
        old_fs = get_fs();
        set_fs(KERNEL_DS);
        err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime));
        set_fs(old_fs);

        return err;
}

static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
                                char __user *optval, unsigned int optlen)
{
        if (optname == SO_ATTACH_FILTER ||
            optname == SO_ATTACH_REUSEPORT_CBPF)
                return do_set_attach_filter(sock, level, optname,
                                            optval, optlen);
        if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
                return do_set_sock_timeout(sock, level, optname, optval, optlen);

        return sock_setsockopt(sock, level, optname, optval, optlen);
}

COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
                       char __user *, optval, unsigned int, optlen)
{
        int err;
        struct socket *sock = sockfd_lookup(fd, &err);

        if (sock) {
                err = security_socket_setsockopt(sock, level, optname);
                if (err) {
                        sockfd_put(sock);
                        return err;
                }

                if (level == SOL_SOCKET)
                        err = compat_sock_setsockopt(sock, level,
                                        optname, optval, optlen);
                else if (sock->ops->compat_setsockopt)
                        err = sock->ops->compat_setsockopt(sock, level,
                                        optname, optval, optlen);
                else
                        err = sock->ops->setsockopt(sock, level,
                                        optname, optval, optlen);
                sockfd_put(sock);
        }
        return err;
}

static int do_get_sock_timeout(struct socket *sock, int level, int optname,
                char __user *optval, int __user *optlen)
{
        struct compat_timeval __user *up;
        struct timeval ktime;
        mm_segment_t old_fs;
        int len, err;

        up = (struct compat_timeval __user *) optval;
        if (get_user(len, optlen))
                return -EFAULT;
        if (len < sizeof(*up))
                return -EINVAL;
        len = sizeof(ktime);
        old_fs = get_fs();
        set_fs(KERNEL_DS);
        err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
        set_fs(old_fs);

        if (!err) {
                if (put_user(sizeof(*up), optlen) ||
                    !access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
                    __put_user(ktime.tv_sec, &up->tv_sec) ||
                    __put_user(ktime.tv_usec, &up->tv_usec))
                        err = -EFAULT;
        }
        return err;
}

static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
                                char __user *optval, int __user *optlen)
{
        if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
                return do_get_sock_timeout(sock, level, optname, optval, optlen);
        return sock_getsockopt(sock, level, optname, optval, optlen);
}

int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
{
        struct compat_timeval __user *ctv;
        int err;
        struct timeval tv;

        if (COMPAT_USE_64BIT_TIME)
                return sock_get_timestamp(sk, userstamp);

        ctv = (struct compat_timeval __user *) userstamp;
        err = -ENOENT;
        if (!sock_flag(sk, SOCK_TIMESTAMP))
                sock_enable_timestamp(sk, SOCK_TIMESTAMP);
        tv = ktime_to_timeval(sk->sk_stamp);
        if (tv.tv_sec == -1)
                return err;
        if (tv.tv_sec == 0) {
                sk->sk_stamp = ktime_get_real();
                tv = ktime_to_timeval(sk->sk_stamp);
        }
        err = 0;
        if (put_user(tv.tv_sec, &ctv->tv_sec) ||
                        put_user(tv.tv_usec, &ctv->tv_usec))
                err = -EFAULT;
        return err;
}
EXPORT_SYMBOL(compat_sock_get_timestamp);

int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
{
        struct compat_timespec __user *ctv;
        int err;
        struct timespec ts;

        if (COMPAT_USE_64BIT_TIME)
                return sock_get_timestampns (sk, userstamp);

        ctv = (struct compat_timespec __user *) userstamp;
        err = -ENOENT;
        if (!sock_flag(sk, SOCK_TIMESTAMP))
                sock_enable_timestamp(sk, SOCK_TIMESTAMP);
        ts = ktime_to_timespec(sk->sk_stamp);
        if (ts.tv_sec == -1)
                return err;
        if (ts.tv_sec == 0) {
                sk->sk_stamp = ktime_get_real();
                ts = ktime_to_timespec(sk->sk_stamp);
        }
        err = 0;
        if (put_user(ts.tv_sec, &ctv->tv_sec) ||
                        put_user(ts.tv_nsec, &ctv->tv_nsec))
                err = -EFAULT;
        return err;
}
EXPORT_SYMBOL(compat_sock_get_timestampns);

COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
                       char __user *, optval, int __user *, optlen)
{
        int err;
        struct socket *sock = sockfd_lookup(fd, &err);

        if (sock) {
                err = security_socket_getsockopt(sock, level, optname);
                if (err) {
                        sockfd_put(sock);
                        return err;
                }

                if (level == SOL_SOCKET)
                        err = compat_sock_getsockopt(sock, level,
                                        optname, optval, optlen);
                else if (sock->ops->compat_getsockopt)
                        err = sock->ops->compat_getsockopt(sock, level,
                                        optname, optval, optlen);
                else
                        err = sock->ops->getsockopt(sock, level,
                                        optname, optval, optlen);
                sockfd_put(sock);
        }
        return err;
}

struct compat_group_req {
        __u32                            gr_interface;
        struct __kernel_sockaddr_storage gr_group
                __aligned(4);
} __packed;

struct compat_group_source_req {
        __u32                            gsr_interface;
        struct __kernel_sockaddr_storage gsr_group
                __aligned(4);
        struct __kernel_sockaddr_storage gsr_source
                __aligned(4);
} __packed;

struct compat_group_filter {
        __u32                            gf_interface;
        struct __kernel_sockaddr_storage gf_group
                __aligned(4);
        __u32                            gf_fmode;
        __u32                            gf_numsrc;
        struct __kernel_sockaddr_storage gf_slist[1]
                __aligned(4);
} __packed;

#define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
                        sizeof(struct __kernel_sockaddr_storage))


int compat_mc_setsockopt(struct sock *sock, int level, int optname,
        char __user *optval, unsigned int optlen,
        int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
{
        char __user     *koptval = optval;
        int             koptlen = optlen;

        switch (optname) {
        case MCAST_JOIN_GROUP:
        case MCAST_LEAVE_GROUP:
        {
                struct compat_group_req __user *gr32 = (void *)optval;
                struct group_req __user *kgr =
                        compat_alloc_user_space(sizeof(struct group_req));
                u32 interface;

                if (!access_ok(VERIFY_READ, gr32, sizeof(*gr32)) ||
                    !access_ok(VERIFY_WRITE, kgr, sizeof(struct group_req)) ||
                    __get_user(interface, &gr32->gr_interface) ||
                    __put_user(interface, &kgr->gr_interface) ||
                    copy_in_user(&kgr->gr_group, &gr32->gr_group,
                                sizeof(kgr->gr_group)))
                        return -EFAULT;
                koptval = (char __user *)kgr;
                koptlen = sizeof(struct group_req);
                break;
        }
        case MCAST_JOIN_SOURCE_GROUP:
        case MCAST_LEAVE_SOURCE_GROUP:
        case MCAST_BLOCK_SOURCE:
        case MCAST_UNBLOCK_SOURCE:
        {
                struct compat_group_source_req __user *gsr32 = (void *)optval;
                struct group_source_req __user *kgsr = compat_alloc_user_space(
                        sizeof(struct group_source_req));
                u32 interface;

                if (!access_ok(VERIFY_READ, gsr32, sizeof(*gsr32)) ||
                    !access_ok(VERIFY_WRITE, kgsr,
                        sizeof(struct group_source_req)) ||
                    __get_user(interface, &gsr32->gsr_interface) ||
                    __put_user(interface, &kgsr->gsr_interface) ||
                    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
                                sizeof(kgsr->gsr_group)) ||
                    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
                                sizeof(kgsr->gsr_source)))
                        return -EFAULT;
                koptval = (char __user *)kgsr;
                koptlen = sizeof(struct group_source_req);
                break;
        }
        case MCAST_MSFILTER:
        {
                struct compat_group_filter __user *gf32 = (void *)optval;
                struct group_filter __user *kgf;
                u32 interface, fmode, numsrc;

                if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
                    __get_user(interface, &gf32->gf_interface) ||
                    __get_user(fmode, &gf32->gf_fmode) ||
                    __get_user(numsrc, &gf32->gf_numsrc))
                        return -EFAULT;
                koptlen = optlen + sizeof(struct group_filter) -
                                sizeof(struct compat_group_filter);
                if (koptlen < GROUP_FILTER_SIZE(numsrc))
                        return -EINVAL;
                kgf = compat_alloc_user_space(koptlen);
                if (!access_ok(VERIFY_WRITE, kgf, koptlen) ||
                    __put_user(interface, &kgf->gf_interface) ||
                    __put_user(fmode, &kgf->gf_fmode) ||
                    __put_user(numsrc, &kgf->gf_numsrc) ||
                    copy_in_user(&kgf->gf_group, &gf32->gf_group,
                                sizeof(kgf->gf_group)) ||
                    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
                                numsrc * sizeof(kgf->gf_slist[0]))))
                        return -EFAULT;
                koptval = (char __user *)kgf;
                break;
        }

        default:
                break;
        }
        return setsockopt(sock, level, optname, koptval, koptlen);
}
EXPORT_SYMBOL(compat_mc_setsockopt);

int compat_mc_getsockopt(struct sock *sock, int level, int optname,
        char __user *optval, int __user *optlen,
        int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
{
        struct compat_group_filter __user *gf32 = (void *)optval;
        struct group_filter __user *kgf;
        int __user      *koptlen;
        u32 interface, fmode, numsrc;
        int klen, ulen, err;

        if (optname != MCAST_MSFILTER)
                return getsockopt(sock, level, optname, optval, optlen);

        koptlen = compat_alloc_user_space(sizeof(*koptlen));
        if (!access_ok(VERIFY_READ, optlen, sizeof(*optlen)) ||
            __get_user(ulen, optlen))
                return -EFAULT;

        /* adjust len for pad */
        klen = ulen + sizeof(*kgf) - sizeof(*gf32);

        if (klen < GROUP_FILTER_SIZE(0))
                return -EINVAL;

        if (!access_ok(VERIFY_WRITE, koptlen, sizeof(*koptlen)) ||
            __put_user(klen, koptlen))
                return -EFAULT;

        /* have to allow space for previous compat_alloc_user_space, too */
        kgf = compat_alloc_user_space(klen+sizeof(*optlen));

        if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
            __get_user(interface, &gf32->gf_interface) ||
            __get_user(fmode, &gf32->gf_fmode) ||
            __get_user(numsrc, &gf32->gf_numsrc) ||
            __put_user(interface, &kgf->gf_interface) ||
            __put_user(fmode, &kgf->gf_fmode) ||
            __put_user(numsrc, &kgf->gf_numsrc) ||
            copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
                return -EFAULT;

        err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
        if (err)
                return err;

        if (!access_ok(VERIFY_READ, koptlen, sizeof(*koptlen)) ||
            __get_user(klen, koptlen))
                return -EFAULT;

        ulen = klen - (sizeof(*kgf)-sizeof(*gf32));

        if (!access_ok(VERIFY_WRITE, optlen, sizeof(*optlen)) ||
            __put_user(ulen, optlen))
                return -EFAULT;

        if (!access_ok(VERIFY_READ, kgf, klen) ||
            !access_ok(VERIFY_WRITE, gf32, ulen) ||
            __get_user(interface, &kgf->gf_interface) ||
            __get_user(fmode, &kgf->gf_fmode) ||
            __get_user(numsrc, &kgf->gf_numsrc) ||
            __put_user(interface, &gf32->gf_interface) ||
            __put_user(fmode, &gf32->gf_fmode) ||
            __put_user(numsrc, &gf32->gf_numsrc))
                return -EFAULT;
        if (numsrc) {
                int copylen;

                klen -= GROUP_FILTER_SIZE(0);
                copylen = numsrc * sizeof(gf32->gf_slist[0]);
                if (copylen > klen)
                        copylen = klen;
                if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
                        return -EFAULT;
        }
        return err;
}
EXPORT_SYMBOL(compat_mc_getsockopt);


/* Argument list sizes for compat_sys_socketcall */
#define AL(x) ((x) * sizeof(u32))
static unsigned char nas[21] = {
        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),
        AL(4), AL(5), AL(4)
};
#undef AL

COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
{
        return __sys_sendmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
}

COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
                       unsigned int, vlen, unsigned int, flags)
{
        return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
                              flags | MSG_CMSG_COMPAT);
}

COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
{
        return __sys_recvmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
}

COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
{
        return sys_recv(fd, buf, len, flags | MSG_CMSG_COMPAT);
}

COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
                       unsigned int, flags, struct sockaddr __user *, addr,
                       int __user *, addrlen)
{
        return sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, addrlen);
}

COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
                       unsigned int, vlen, unsigned int, flags,
                       struct compat_timespec __user *, timeout)
{
        int datagrams;
        struct timespec ktspec;

        if (timeout == NULL)
                return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
                                      flags | MSG_CMSG_COMPAT, NULL);

        if (compat_get_timespec(&ktspec, timeout))
                return -EFAULT;

        datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
                                   flags | MSG_CMSG_COMPAT, &ktspec);
        if (datagrams > 0 && compat_put_timespec(&ktspec, timeout))
                datagrams = -EFAULT;

        return datagrams;
}

COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
{
        u32 a[AUDITSC_ARGS];
        unsigned int len;
        u32 a0, a1;
        int ret;

        if (call < SYS_SOCKET || call > SYS_SENDMMSG)
                return -EINVAL;
        len = nas[call];
        if (len > sizeof(a))
                return -EINVAL;

        if (copy_from_user(a, args, len))
                return -EFAULT;

        ret = audit_socketcall_compat(len / sizeof(a[0]), a);
        if (ret)
                return ret;

        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, compat_ptr(a1), a[2]);
                break;
        case SYS_CONNECT:
                ret = sys_connect(a0, compat_ptr(a1), a[2]);
                break;
        case SYS_LISTEN:
                ret = sys_listen(a0, a1);
                break;
        case SYS_ACCEPT:
                ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
                break;
        case SYS_GETSOCKNAME:
                ret = sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
                break;
        case SYS_GETPEERNAME:
                ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
                break;
        case SYS_SOCKETPAIR:
                ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
                break;
        case SYS_SEND:
                ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);
                break;
        case SYS_SENDTO:
                ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]);
                break;
        case SYS_RECV:
                ret = compat_sys_recv(a0, compat_ptr(a1), a[2], a[3]);
                break;
        case SYS_RECVFROM:
                ret = compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
                                          compat_ptr(a[4]), compat_ptr(a[5]));
                break;
        case SYS_SHUTDOWN:
                ret = sys_shutdown(a0, a1);
                break;
        case SYS_SETSOCKOPT:
                ret = compat_sys_setsockopt(a0, a1, a[2],
                                compat_ptr(a[3]), a[4]);
                break;
        case SYS_GETSOCKOPT:
                ret = compat_sys_getsockopt(a0, a1, a[2],
                                compat_ptr(a[3]), compat_ptr(a[4]));
                break;
        case SYS_SENDMSG:
                ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
                break;
        case SYS_SENDMMSG:
                ret = compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
                break;
        case SYS_RECVMSG:
                ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
                break;
        case SYS_RECVMMSG:
                ret = compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3],
                                          compat_ptr(a[4]));
                break;
        case SYS_ACCEPT4:
                ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
                break;
        default:
                ret = -EINVAL;
                break;
        }
        return ret;
}