linux-stable/net/compat.c
Dmitry Mishin 2722971cbe [NETFILTER]: iptables 32bit compat layer
This patch extends current iptables compatibility layer in order to get
32bit iptables to work on 64bit kernel. Current layer is insufficient due
to alignment checks both in kernel and user space tools.

Patch is for current net-2.6.17 with addition of move of ipt_entry_{match|
target} definitions to xt_entry_{match|target}.

Signed-off-by: Dmitry Mishin <dim@openvz.org>
Acked-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-01 02:25:19 -08:00

681 lines
18 KiB
C

/*
* 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/fs.h>
#include <linux/sched.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/netfilter_ipv4/ip_tables.h>
#include <linux/security.h>
#include <net/scm.h>
#include <net/sock.h>
#include <asm/uaccess.h>
#include <net/compat.h>
static inline int iov_from_user_compat_to_kern(struct iovec *kiov,
struct compat_iovec __user *uiov32,
int niov)
{
int tot_len = 0;
while(niov > 0) {
compat_uptr_t buf;
compat_size_t len;
if(get_user(len, &uiov32->iov_len) ||
get_user(buf, &uiov32->iov_base)) {
tot_len = -EFAULT;
break;
}
tot_len += len;
kiov->iov_base = compat_ptr(buf);
kiov->iov_len = (__kernel_size_t) len;
uiov32++;
kiov++;
niov--;
}
return tot_len;
}
int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg)
{
compat_uptr_t tmp1, tmp2, tmp3;
if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
__get_user(tmp1, &umsg->msg_name) ||
__get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
__get_user(tmp2, &umsg->msg_iov) ||
__get_user(kmsg->msg_iovlen, &umsg->msg_iovlen) ||
__get_user(tmp3, &umsg->msg_control) ||
__get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
__get_user(kmsg->msg_flags, &umsg->msg_flags))
return -EFAULT;
kmsg->msg_name = compat_ptr(tmp1);
kmsg->msg_iov = compat_ptr(tmp2);
kmsg->msg_control = compat_ptr(tmp3);
return 0;
}
/* I've named the args so it is easy to tell whose space the pointers are in. */
int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
char *kern_address, int mode)
{
int tot_len;
if(kern_msg->msg_namelen) {
if(mode==VERIFY_READ) {
int err = move_addr_to_kernel(kern_msg->msg_name,
kern_msg->msg_namelen,
kern_address);
if(err < 0)
return err;
}
kern_msg->msg_name = kern_address;
} else
kern_msg->msg_name = NULL;
tot_len = iov_from_user_compat_to_kern(kern_iov,
(struct compat_iovec __user *)kern_msg->msg_iov,
kern_msg->msg_iovlen);
if(tot_len >= 0)
kern_msg->msg_iov = kern_iov;
return tot_len;
}
/* Bleech... */
#define CMSG_COMPAT_ALIGN(len) ALIGN((len), sizeof(s32))
#define CMSG_COMPAT_DATA(cmsg) \
((void __user *)((char __user *)(cmsg) + CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))))
#define CMSG_COMPAT_SPACE(len) \
(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + CMSG_COMPAT_ALIGN(len))
#define CMSG_COMPAT_LEN(len) \
(CMSG_COMPAT_ALIGN(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;
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 - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
CMSG_ALIGN(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 - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
CMSG_ALIGN(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 - CMSG_COMPAT_ALIGN(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_timeval ctv;
struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
struct compat_cmsghdr cmhdr;
int cmlen;
if(cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
kmsg->msg_flags |= MSG_CTRUNC;
return 0; /* XXX: return error? check spec. */
}
if (level == SOL_SOCKET && type == SO_TIMESTAMP) {
struct timeval *tv = (struct timeval *)data;
ctv.tv_sec = tv->tv_sec;
ctv.tv_usec = tv->tv_usec;
data = &ctv;
len = sizeof(struct compat_timeval);
}
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);
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();
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. */
get_file(fp[i]);
fd_install(new_fd, fp[i]);
}
if (i > 0) {
int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
if (!err)
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);
}
/*
* For now, we assume that the compatibility and native version
* of struct ipt_entry are the same - sfr. FIXME
*/
struct compat_ipt_replace {
char name[IPT_TABLE_MAXNAMELEN];
u32 valid_hooks;
u32 num_entries;
u32 size;
u32 hook_entry[NF_IP_NUMHOOKS];
u32 underflow[NF_IP_NUMHOOKS];
u32 num_counters;
compat_uptr_t counters; /* struct ipt_counters * */
struct ipt_entry entries[0];
};
static int do_netfilter_replace(int fd, int level, int optname,
char __user *optval, int optlen)
{
struct compat_ipt_replace __user *urepl;
struct ipt_replace __user *repl_nat;
char name[IPT_TABLE_MAXNAMELEN];
u32 origsize, tmp32, num_counters;
unsigned int repl_nat_size;
int ret;
int i;
compat_uptr_t ucntrs;
urepl = (struct compat_ipt_replace __user *)optval;
if (get_user(origsize, &urepl->size))
return -EFAULT;
/* Hack: Causes ipchains to give correct error msg --RR */
if (optlen != sizeof(*urepl) + origsize)
return -ENOPROTOOPT;
/* XXX Assumes that size of ipt_entry is the same both in
* native and compat environments.
*/
repl_nat_size = sizeof(*repl_nat) + origsize;
repl_nat = compat_alloc_user_space(repl_nat_size);
ret = -EFAULT;
if (put_user(origsize, &repl_nat->size))
goto out;
if (!access_ok(VERIFY_READ, urepl, optlen) ||
!access_ok(VERIFY_WRITE, repl_nat, optlen))
goto out;
if (__copy_from_user(name, urepl->name, sizeof(urepl->name)) ||
__copy_to_user(repl_nat->name, name, sizeof(repl_nat->name)))
goto out;
if (__get_user(tmp32, &urepl->valid_hooks) ||
__put_user(tmp32, &repl_nat->valid_hooks))
goto out;
if (__get_user(tmp32, &urepl->num_entries) ||
__put_user(tmp32, &repl_nat->num_entries))
goto out;
if (__get_user(num_counters, &urepl->num_counters) ||
__put_user(num_counters, &repl_nat->num_counters))
goto out;
if (__get_user(ucntrs, &urepl->counters) ||
__put_user(compat_ptr(ucntrs), &repl_nat->counters))
goto out;
if (__copy_in_user(&repl_nat->entries[0],
&urepl->entries[0],
origsize))
goto out;
for (i = 0; i < NF_IP_NUMHOOKS; i++) {
if (__get_user(tmp32, &urepl->hook_entry[i]) ||
__put_user(tmp32, &repl_nat->hook_entry[i]) ||
__get_user(tmp32, &urepl->underflow[i]) ||
__put_user(tmp32, &repl_nat->underflow[i]))
goto out;
}
/*
* Since struct ipt_counters just contains two u_int64_t members
* we can just do the access_ok check here and pass the (converted)
* pointer into the standard syscall. We hope that the pointer is
* not misaligned ...
*/
if (!access_ok(VERIFY_WRITE, compat_ptr(ucntrs),
num_counters * sizeof(struct ipt_counters)))
goto out;
ret = sys_setsockopt(fd, level, optname,
(char __user *)repl_nat, repl_nat_size);
out:
return ret;
}
/*
* A struct sock_filter is architecture independent.
*/
struct compat_sock_fprog {
u16 len;
compat_uptr_t filter; /* struct sock_filter * */
};
static int do_set_attach_filter(struct socket *sock, int level, int optname,
char __user *optval, int optlen)
{
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));
compat_uptr_t ptr;
u16 len;
if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
!access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
__get_user(len, &fprog32->len) ||
__get_user(ptr, &fprog32->filter) ||
__put_user(len, &kfprog->len) ||
__put_user(compat_ptr(ptr), &kfprog->filter))
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, 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, int optlen)
{
if (optname == SO_ATTACH_FILTER)
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);
}
asmlinkage long compat_sys_setsockopt(int fd, int level, int optname,
char __user *optval, int optlen)
{
int err;
struct socket *sock;
if (level == SOL_IPV6 && optname == IPT_SO_SET_REPLACE)
return do_netfilter_replace(fd, level, optname,
optval, optlen);
if (optlen < 0)
return -EINVAL;
if ((sock = sockfd_lookup(fd, &err))!=NULL)
{
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 =
(struct compat_timeval __user*) userstamp;
int err = -ENOENT;
if (!sock_flag(sk, SOCK_TIMESTAMP))
sock_enable_timestamp(sk);
if (sk->sk_stamp.tv_sec == -1)
return err;
if (sk->sk_stamp.tv_sec == 0)
do_gettimeofday(&sk->sk_stamp);
if (put_user(sk->sk_stamp.tv_sec, &ctv->tv_sec) ||
put_user(sk->sk_stamp.tv_usec, &ctv->tv_usec))
err = -EFAULT;
return err;
}
EXPORT_SYMBOL(compat_sock_get_timestamp);
asmlinkage long compat_sys_getsockopt(int fd, int level, int optname,
char __user *optval, int __user *optlen)
{
int err;
struct socket *sock;
if ((sock = sockfd_lookup(fd, &err))!=NULL)
{
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;
}
/* Argument list sizes for compat_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
asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg, unsigned flags)
{
return sys_sendmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
}
asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, unsigned int flags)
{
return sys_recvmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
}
asmlinkage long compat_sys_socketcall(int call, u32 __user *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, 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_accept(a0, compat_ptr(a1), compat_ptr(a[2]));
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 = sys_recv(a0, compat_ptr(a1), a[2], a[3]);
break;
case SYS_RECVFROM:
ret = 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_RECVMSG:
ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
break;
default:
ret = -EINVAL;
break;
}
return ret;
}