static int vif_add(struct vifctl *vifc, int mrtsock) { int vifi = vifc->vifc_vifi; struct vif_device *v = &vif_table[vifi]; struct net_device *dev; struct in_device *in_dev; /*[Santosh: to add "ppp" interface into VIF table]*/ #if defined (CONFIG_IFX_IGMP_PROXY) || defined (CONFIG_IFX_IGMP_PROXY_MODULE) struct in_device *ip; struct in_ifaddr *in; __u32 addr; dev=ip_dev_find(vifc->vifc_lcl_addr.s_addr); if (dev) __dev_put(dev); if (!dev){ addr = vifc->vifc_lcl_addr.s_addr; for(dev = dev_base; dev; dev = dev->next){ if (dev == NULL) continue; if (strncmp (dev->name,"ppp",3) != 0) continue; ip = dev->ip_ptr; if( (ip == NULL) || ((in = ip->ifa_list) == NULL )) { DBPRINT ("vif_add: Device: %s not assigned IP address\n",dev->name); } if (( in->ifa_address == addr ) && (strncmp (dev->name,"ppp",3) == 0)) { break; } } } // if (!dev) #endif /* Is vif busy ? */ if (VIF_EXISTS(vifi)) return -EADDRINUSE; switch (vifc->vifc_flags) { #ifdef CONFIG_IP_PIMSM case VIFF_REGISTER: /* * Special Purpose VIF in PIM * All the packets will be sent to the daemon */ if (reg_vif_num >= 0) return -EADDRINUSE; dev = ipmr_reg_vif(vifc); if (!dev) return -ENOBUFS; break; #endif case VIFF_TUNNEL: dev = ipmr_new_tunnel(vifc); if (!dev) return -ENOBUFS; break; case 0: /*[Santosh: to add "ppp" interface into VIF table]*/ #if defined (CONFIG_IFX_IGMP_PROXY) || defined (CONFIG_IFX_IGMP_PROXY_MODULE) if (strncmp (dev->name, "ppp",3) == 0) { break; } #endif dev=ip_dev_find(vifc->vifc_lcl_addr.s_addr); if (!dev) return -EADDRNOTAVAIL; __dev_put(dev); break; default: return -EINVAL; } if ((in_dev = __in_dev_get(dev)) == NULL) return -EADDRNOTAVAIL; in_dev->cnf.mc_forwarding++; dev_set_allmulti(dev, +1); ip_rt_multicast_event(in_dev); /* * Fill in the VIF structures */ v->rate_limit=vifc->vifc_rate_limit; v->local=vifc->vifc_lcl_addr.s_addr; v->remote=vifc->vifc_rmt_addr.s_addr; v->flags=vifc->vifc_flags; if (!mrtsock) v->flags |= VIFF_STATIC; v->threshold=vifc->vifc_threshold; v->bytes_in = 0; v->bytes_out = 0; v->pkt_in = 0; v->pkt_out = 0; v->link = dev->ifindex; if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER)) v->link = dev->iflink; /* And finish update writing critical data */ write_lock_bh(&mrt_lock); dev_hold(dev); v->dev=dev; #ifdef CONFIG_IP_PIMSM if (v->flags&VIFF_REGISTER) reg_vif_num = vifi; #endif if (vifi+1 > maxvif) maxvif = vifi+1; write_unlock_bh(&mrt_lock); return 0; }
static int do_ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen) { struct inet_sock *inet = inet_sk(sk); int val = 0, err; bool needs_rtnl = setsockopt_needs_rtnl(optname); switch (optname) { case IP_PKTINFO: case IP_RECVTTL: case IP_RECVOPTS: case IP_RECVTOS: case IP_RETOPTS: case IP_TOS: case IP_TTL: case IP_HDRINCL: case IP_MTU_DISCOVER: case IP_RECVERR: case IP_ROUTER_ALERT: case IP_FREEBIND: case IP_PASSSEC: case IP_TRANSPARENT: case IP_MINTTL: case IP_NODEFRAG: case IP_BIND_ADDRESS_NO_PORT: case IP_UNICAST_IF: case IP_MULTICAST_TTL: case IP_MULTICAST_ALL: case IP_MULTICAST_LOOP: case IP_RECVORIGDSTADDR: case IP_CHECKSUM: if (optlen >= sizeof(int)) { if (get_user(val, (int __user *) optval)) return -EFAULT; } else if (optlen >= sizeof(char)) { unsigned char ucval; if (get_user(ucval, (unsigned char __user *) optval)) return -EFAULT; val = (int) ucval; } } /* If optlen==0, it is equivalent to val == 0 */ if (ip_mroute_opt(optname)) return ip_mroute_setsockopt(sk, optname, optval, optlen); err = 0; if (needs_rtnl) rtnl_lock(); lock_sock(sk); switch (optname) { case IP_OPTIONS: { struct ip_options_rcu *old, *opt = NULL; if (optlen > 40) goto e_inval; err = ip_options_get_from_user(sock_net(sk), &opt, optval, optlen); if (err) break; old = rcu_dereference_protected(inet->inet_opt, sock_owned_by_user(sk)); if (inet->is_icsk) { struct inet_connection_sock *icsk = inet_csk(sk); #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == PF_INET || (!((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) && inet->inet_daddr != LOOPBACK4_IPV6)) { #endif if (old) icsk->icsk_ext_hdr_len -= old->opt.optlen; if (opt) icsk->icsk_ext_hdr_len += opt->opt.optlen; icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie); #if IS_ENABLED(CONFIG_IPV6) } #endif } rcu_assign_pointer(inet->inet_opt, opt); if (old) kfree_rcu(old, rcu); break; } case IP_PKTINFO: if (val) inet->cmsg_flags |= IP_CMSG_PKTINFO; else inet->cmsg_flags &= ~IP_CMSG_PKTINFO; break; case IP_RECVTTL: if (val) inet->cmsg_flags |= IP_CMSG_TTL; else inet->cmsg_flags &= ~IP_CMSG_TTL; break; case IP_RECVTOS: if (val) inet->cmsg_flags |= IP_CMSG_TOS; else inet->cmsg_flags &= ~IP_CMSG_TOS; break; case IP_RECVOPTS: if (val) inet->cmsg_flags |= IP_CMSG_RECVOPTS; else inet->cmsg_flags &= ~IP_CMSG_RECVOPTS; break; case IP_RETOPTS: if (val) inet->cmsg_flags |= IP_CMSG_RETOPTS; else inet->cmsg_flags &= ~IP_CMSG_RETOPTS; break; case IP_PASSSEC: if (val) inet->cmsg_flags |= IP_CMSG_PASSSEC; else inet->cmsg_flags &= ~IP_CMSG_PASSSEC; break; case IP_RECVORIGDSTADDR: if (val) inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR; else inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR; break; case IP_CHECKSUM: if (val) { if (!(inet->cmsg_flags & IP_CMSG_CHECKSUM)) { inet_inc_convert_csum(sk); inet->cmsg_flags |= IP_CMSG_CHECKSUM; } } else { if (inet->cmsg_flags & IP_CMSG_CHECKSUM) { inet_dec_convert_csum(sk); inet->cmsg_flags &= ~IP_CMSG_CHECKSUM; } } break; case IP_TOS: /* This sets both TOS and Precedence */ if (sk->sk_type == SOCK_STREAM) { val &= ~INET_ECN_MASK; val |= inet->tos & INET_ECN_MASK; } if (inet->tos != val) { inet->tos = val; sk->sk_priority = rt_tos2priority(val); sk_dst_reset(sk); } break; case IP_TTL: if (optlen < 1) goto e_inval; if (val != -1 && (val < 1 || val > 255)) goto e_inval; inet->uc_ttl = val; break; case IP_HDRINCL: if (sk->sk_type != SOCK_RAW) { err = -ENOPROTOOPT; break; } inet->hdrincl = val ? 1 : 0; break; case IP_NODEFRAG: if (sk->sk_type != SOCK_RAW) { err = -ENOPROTOOPT; break; } inet->nodefrag = val ? 1 : 0; break; case IP_BIND_ADDRESS_NO_PORT: inet->bind_address_no_port = val ? 1 : 0; break; case IP_MTU_DISCOVER: if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT) goto e_inval; inet->pmtudisc = val; break; case IP_RECVERR: inet->recverr = !!val; if (!val) skb_queue_purge(&sk->sk_error_queue); break; case IP_MULTICAST_TTL: if (sk->sk_type == SOCK_STREAM) goto e_inval; if (optlen < 1) goto e_inval; if (val == -1) val = 1; if (val < 0 || val > 255) goto e_inval; inet->mc_ttl = val; break; case IP_MULTICAST_LOOP: if (optlen < 1) goto e_inval; inet->mc_loop = !!val; break; case IP_UNICAST_IF: { struct net_device *dev = NULL; int ifindex; if (optlen != sizeof(int)) goto e_inval; ifindex = (__force int)ntohl((__force __be32)val); if (ifindex == 0) { inet->uc_index = 0; err = 0; break; } dev = dev_get_by_index(sock_net(sk), ifindex); err = -EADDRNOTAVAIL; if (!dev) break; dev_put(dev); err = -EINVAL; if (sk->sk_bound_dev_if) break; inet->uc_index = ifindex; err = 0; break; } case IP_MULTICAST_IF: { struct ip_mreqn mreq; struct net_device *dev = NULL; if (sk->sk_type == SOCK_STREAM) goto e_inval; /* * Check the arguments are allowable */ if (optlen < sizeof(struct in_addr)) goto e_inval; err = -EFAULT; if (optlen >= sizeof(struct ip_mreqn)) { if (copy_from_user(&mreq, optval, sizeof(mreq))) break; } else { memset(&mreq, 0, sizeof(mreq)); if (optlen >= sizeof(struct ip_mreq)) { if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq))) break; } else if (optlen >= sizeof(struct in_addr)) { if (copy_from_user(&mreq.imr_address, optval, sizeof(struct in_addr))) break; } } if (!mreq.imr_ifindex) { if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) { inet->mc_index = 0; inet->mc_addr = 0; err = 0; break; } dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr); if (dev) mreq.imr_ifindex = dev->ifindex; } else dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex); err = -EADDRNOTAVAIL; if (!dev) break; dev_put(dev); err = -EINVAL; if (sk->sk_bound_dev_if && mreq.imr_ifindex != sk->sk_bound_dev_if) break; inet->mc_index = mreq.imr_ifindex; inet->mc_addr = mreq.imr_address.s_addr; err = 0; break; } case IP_ADD_MEMBERSHIP: case IP_DROP_MEMBERSHIP: { struct ip_mreqn mreq; err = -EPROTO; if (inet_sk(sk)->is_icsk) break; if (optlen < sizeof(struct ip_mreq)) goto e_inval; err = -EFAULT; if (optlen >= sizeof(struct ip_mreqn)) { if (copy_from_user(&mreq, optval, sizeof(mreq))) break; } else { memset(&mreq, 0, sizeof(mreq)); if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq))) break; } if (optname == IP_ADD_MEMBERSHIP) err = ip_mc_join_group(sk, &mreq); else err = ip_mc_leave_group(sk, &mreq); break; } case IP_MSFILTER: { struct ip_msfilter *msf; if (optlen < IP_MSFILTER_SIZE(0)) goto e_inval; if (optlen > sysctl_optmem_max) { err = -ENOBUFS; break; } msf = kmalloc(optlen, GFP_KERNEL); if (!msf) { err = -ENOBUFS; break; } err = -EFAULT; if (copy_from_user(msf, optval, optlen)) { kfree(msf); break; } /* numsrc >= (1G-4) overflow in 32 bits */ if (msf->imsf_numsrc >= 0x3ffffffcU || msf->imsf_numsrc > sysctl_igmp_max_msf) { kfree(msf); err = -ENOBUFS; break; } if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) { kfree(msf); err = -EINVAL; break; } err = ip_mc_msfilter(sk, msf, 0); kfree(msf); break; } case IP_BLOCK_SOURCE: case IP_UNBLOCK_SOURCE: case IP_ADD_SOURCE_MEMBERSHIP: case IP_DROP_SOURCE_MEMBERSHIP: { struct ip_mreq_source mreqs; int omode, add; if (optlen != sizeof(struct ip_mreq_source)) goto e_inval; if (copy_from_user(&mreqs, optval, sizeof(mreqs))) { err = -EFAULT; break; } if (optname == IP_BLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 1; } else if (optname == IP_UNBLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 0; } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) { struct ip_mreqn mreq; mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr; mreq.imr_address.s_addr = mreqs.imr_interface; mreq.imr_ifindex = 0; err = ip_mc_join_group(sk, &mreq); if (err && err != -EADDRINUSE) break; omode = MCAST_INCLUDE; add = 1; } else /* IP_DROP_SOURCE_MEMBERSHIP */ { omode = MCAST_INCLUDE; add = 0; } err = ip_mc_source(add, omode, sk, &mreqs, 0); break; } case MCAST_JOIN_GROUP: case MCAST_LEAVE_GROUP: { struct group_req greq; struct sockaddr_in *psin; struct ip_mreqn mreq; if (optlen < sizeof(struct group_req)) goto e_inval; err = -EFAULT; if (copy_from_user(&greq, optval, sizeof(greq))) break; psin = (struct sockaddr_in *)&greq.gr_group; if (psin->sin_family != AF_INET) goto e_inval; memset(&mreq, 0, sizeof(mreq)); mreq.imr_multiaddr = psin->sin_addr; mreq.imr_ifindex = greq.gr_interface; if (optname == MCAST_JOIN_GROUP) err = ip_mc_join_group(sk, &mreq); else err = ip_mc_leave_group(sk, &mreq); break; } case MCAST_JOIN_SOURCE_GROUP: case MCAST_LEAVE_SOURCE_GROUP: case MCAST_BLOCK_SOURCE: case MCAST_UNBLOCK_SOURCE: { struct group_source_req greqs; struct ip_mreq_source mreqs; struct sockaddr_in *psin; int omode, add; if (optlen != sizeof(struct group_source_req)) goto e_inval; if (copy_from_user(&greqs, optval, sizeof(greqs))) { err = -EFAULT; break; } if (greqs.gsr_group.ss_family != AF_INET || greqs.gsr_source.ss_family != AF_INET) { err = -EADDRNOTAVAIL; break; } psin = (struct sockaddr_in *)&greqs.gsr_group; mreqs.imr_multiaddr = psin->sin_addr.s_addr; psin = (struct sockaddr_in *)&greqs.gsr_source; mreqs.imr_sourceaddr = psin->sin_addr.s_addr; mreqs.imr_interface = 0; /* use index for mc_source */ if (optname == MCAST_BLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 1; } else if (optname == MCAST_UNBLOCK_SOURCE) { omode = MCAST_EXCLUDE; add = 0; } else if (optname == MCAST_JOIN_SOURCE_GROUP) { struct ip_mreqn mreq; psin = (struct sockaddr_in *)&greqs.gsr_group; mreq.imr_multiaddr = psin->sin_addr; mreq.imr_address.s_addr = 0; mreq.imr_ifindex = greqs.gsr_interface; err = ip_mc_join_group(sk, &mreq); if (err && err != -EADDRINUSE) break; greqs.gsr_interface = mreq.imr_ifindex; omode = MCAST_INCLUDE; add = 1; } else /* MCAST_LEAVE_SOURCE_GROUP */ { omode = MCAST_INCLUDE; add = 0; } err = ip_mc_source(add, omode, sk, &mreqs, greqs.gsr_interface); break; } case MCAST_MSFILTER: { struct sockaddr_in *psin; struct ip_msfilter *msf = NULL; struct group_filter *gsf = NULL; int msize, i, ifindex; if (optlen < GROUP_FILTER_SIZE(0)) goto e_inval; if (optlen > sysctl_optmem_max) { err = -ENOBUFS; break; } gsf = kmalloc(optlen, GFP_KERNEL); if (!gsf) { err = -ENOBUFS; break; } err = -EFAULT; if (copy_from_user(gsf, optval, optlen)) goto mc_msf_out; /* numsrc >= (4G-140)/128 overflow in 32 bits */ if (gsf->gf_numsrc >= 0x1ffffff || gsf->gf_numsrc > sysctl_igmp_max_msf) { err = -ENOBUFS; goto mc_msf_out; } if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) { err = -EINVAL; goto mc_msf_out; } msize = IP_MSFILTER_SIZE(gsf->gf_numsrc); msf = kmalloc(msize, GFP_KERNEL); if (!msf) { err = -ENOBUFS; goto mc_msf_out; } ifindex = gsf->gf_interface; psin = (struct sockaddr_in *)&gsf->gf_group; if (psin->sin_family != AF_INET) { err = -EADDRNOTAVAIL; goto mc_msf_out; } msf->imsf_multiaddr = psin->sin_addr.s_addr; msf->imsf_interface = 0; msf->imsf_fmode = gsf->gf_fmode; msf->imsf_numsrc = gsf->gf_numsrc; err = -EADDRNOTAVAIL; for (i = 0; i < gsf->gf_numsrc; ++i) { psin = (struct sockaddr_in *)&gsf->gf_slist[i]; if (psin->sin_family != AF_INET) goto mc_msf_out; msf->imsf_slist[i] = psin->sin_addr.s_addr; } kfree(gsf); gsf = NULL; err = ip_mc_msfilter(sk, msf, ifindex); mc_msf_out: kfree(msf); kfree(gsf); break; } case IP_MULTICAST_ALL: if (optlen < 1) goto e_inval; if (val != 0 && val != 1) goto e_inval; inet->mc_all = val; break; case IP_ROUTER_ALERT: err = ip_ra_control(sk, val ? 1 : 0, NULL); break; case IP_FREEBIND: if (optlen < 1) goto e_inval; inet->freebind = !!val; break; case IP_IPSEC_POLICY: case IP_XFRM_POLICY: err = -EPERM; if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) break; err = xfrm_user_policy(sk, optname, optval, optlen); break; case IP_TRANSPARENT: if (!!val && !ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) && !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { err = -EPERM; break; } if (optlen < 1) goto e_inval; inet->transparent = !!val; break; case IP_MINTTL: if (optlen < 1) goto e_inval; if (val < 0 || val > 255) goto e_inval; inet->min_ttl = val; break; default: err = -ENOPROTOOPT; break; } release_sock(sk); if (needs_rtnl) rtnl_unlock(); return err; e_inval: release_sock(sk); if (needs_rtnl) rtnl_unlock(); return -EINVAL; }
static int vif_add(struct net *net, struct vifctl *vifc, int mrtsock) { int vifi = vifc->vifc_vifi; struct vif_device *v = &net->ipv4.vif_table[vifi]; struct net_device *dev; struct in_device *in_dev; int err; /* Is vif busy ? */ if (VIF_EXISTS(net, vifi)) return -EADDRINUSE; switch (vifc->vifc_flags) { #ifdef CONFIG_IP_PIMSM case VIFF_REGISTER: /* * Special Purpose VIF in PIM * All the packets will be sent to the daemon */ if (net->ipv4.mroute_reg_vif_num >= 0) return -EADDRINUSE; dev = ipmr_reg_vif(net); if (!dev) return -ENOBUFS; err = dev_set_allmulti(dev, 1); if (err) { unregister_netdevice(dev); dev_put(dev); return err; } break; #endif case VIFF_TUNNEL: dev = ipmr_new_tunnel(net, vifc); if (!dev) return -ENOBUFS; err = dev_set_allmulti(dev, 1); if (err) { ipmr_del_tunnel(dev, vifc); dev_put(dev); return err; } break; case VIFF_USE_IFINDEX: case 0: if (vifc->vifc_flags == VIFF_USE_IFINDEX) { dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex); if (dev && dev->ip_ptr == NULL) { dev_put(dev); return -EADDRNOTAVAIL; } } else dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr); if (!dev) return -EADDRNOTAVAIL; err = dev_set_allmulti(dev, 1); if (err) { dev_put(dev); return err; } break; default: return -EINVAL; } if ((in_dev = __in_dev_get_rtnl(dev)) == NULL) { dev_put(dev); return -EADDRNOTAVAIL; } IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++; ip_rt_multicast_event(in_dev); /* * Fill in the VIF structures */ v->rate_limit = vifc->vifc_rate_limit; v->local = vifc->vifc_lcl_addr.s_addr; v->remote = vifc->vifc_rmt_addr.s_addr; v->flags = vifc->vifc_flags; if (!mrtsock) v->flags |= VIFF_STATIC; v->threshold = vifc->vifc_threshold; v->bytes_in = 0; v->bytes_out = 0; v->pkt_in = 0; v->pkt_out = 0; v->link = dev->ifindex; if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER)) v->link = dev->iflink; /* And finish update writing critical data */ write_lock_bh(&mrt_lock); v->dev = dev; #ifdef CONFIG_IP_PIMSM if (v->flags&VIFF_REGISTER) net->ipv4.mroute_reg_vif_num = vifi; #endif if (vifi+1 > net->ipv4.maxvif) net->ipv4.maxvif = vifi+1; write_unlock_bh(&mrt_lock); return 0; }
static int vif_add(struct vifctl *vifc, int mrtsock) { int vifi = vifc->vifc_vifi; struct vif_device *v = &vif_table[vifi]; struct net_device *dev; struct in_device *in_dev; /* Is vif busy ? */ if (VIF_EXISTS(vifi)) return -EADDRINUSE; switch (vifc->vifc_flags) { #ifdef CONFIG_IP_PIMSM case VIFF_REGISTER: /* * Special Purpose VIF in PIM * All the packets will be sent to the daemon */ if (reg_vif_num >= 0) return -EADDRINUSE; dev = ipmr_reg_vif(vifc); if (!dev) return -ENOBUFS; break; #endif case VIFF_TUNNEL: dev = ipmr_new_tunnel(vifc); if (!dev) return -ENOBUFS; break; case 0: dev=ip_dev_find(vifc->vifc_lcl_addr.s_addr); if (!dev) return -EADDRNOTAVAIL; __dev_put(dev); break; default: return -EINVAL; } if ((in_dev = __in_dev_get(dev)) == NULL) return -EADDRNOTAVAIL; in_dev->cnf.mc_forwarding++; dev_set_allmulti(dev, +1); ip_rt_multicast_event(in_dev); /* * Fill in the VIF structures */ v->rate_limit=vifc->vifc_rate_limit; v->local=vifc->vifc_lcl_addr.s_addr; v->remote=vifc->vifc_rmt_addr.s_addr; v->flags=vifc->vifc_flags; if (!mrtsock) v->flags |= VIFF_STATIC; v->threshold=vifc->vifc_threshold; v->bytes_in = 0; v->bytes_out = 0; v->pkt_in = 0; v->pkt_out = 0; v->link = dev->ifindex; if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER)) v->link = dev->iflink; /* And finish update writing critical data */ write_lock_bh(&mrt_lock); dev_hold(dev); v->dev=dev; #ifdef CONFIG_IP_PIMSM if (v->flags&VIFF_REGISTER) reg_vif_num = vifi; #endif if (vifi+1 > maxvif) maxvif = vifi+1; write_unlock_bh(&mrt_lock); return 0; }