diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/Kconfig | 20 | ||||
| -rw-r--r-- | net/compat.c | 17 | ||||
| -rw-r--r-- | net/netlink/af_netlink.c | 36 | ||||
| -rw-r--r-- | net/wireless/wext.c | 78 |
4 files changed, 148 insertions, 3 deletions
diff --git a/net/Kconfig b/net/Kconfig index 7051b97..041c35e 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -23,6 +23,26 @@ menuconfig NET if NET +config WANT_COMPAT_NETLINK_MESSAGES + bool + help + This option can be selected by other options that need compat + netlink messages. + +config COMPAT_NETLINK_MESSAGES + def_bool y + depends on COMPAT + depends on WIRELESS_EXT || WANT_COMPAT_NETLINK_MESSAGES + help + This option makes it possible to send different netlink messages + to tasks depending on whether the task is a compat task or not. To + achieve this, you need to set skb_shinfo(skb)->frag_list to the + compat skb before sending the skb, the netlink code will sort out + which message to actually pass to the task. + + Newly written code should NEVER need this option but do + compat-independent messages instead! + menu "Networking options" source "net/packet/Kconfig" diff --git a/net/compat.c b/net/compat.c index 8d73905..12728b1 100644 --- a/net/compat.c +++ b/net/compat.c @@ -743,6 +743,18 @@ asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, uns return sys_recvmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT); } +asmlinkage long compat_sys_recv(int fd, void __user *buf, size_t len, unsigned flags) +{ + return sys_recv(fd, buf, len, flags | MSG_CMSG_COMPAT); +} + +asmlinkage long compat_sys_recvfrom(int fd, void __user *buf, size_t len, + unsigned flags, struct sockaddr __user *addr, + int __user *addrlen) +{ + return sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, addrlen); +} + asmlinkage long compat_sys_socketcall(int call, u32 __user *args) { int ret; @@ -788,10 +800,11 @@ asmlinkage long compat_sys_socketcall(int call, u32 __user *args) 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]); + ret = compat_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])); + 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); diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index d46da6c..da3163d 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1361,7 +1361,7 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, struct netlink_sock *nlk = nlk_sk(sk); int noblock = flags&MSG_DONTWAIT; size_t copied; - struct sk_buff *skb; + struct sk_buff *skb, *frag __maybe_unused = NULL; int err; if (flags&MSG_OOB) @@ -1373,6 +1373,35 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, if (skb == NULL) goto out; +#ifdef CONFIG_COMPAT_NETLINK_MESSAGES + if (unlikely(skb_shinfo(skb)->frag_list)) { + bool need_compat = !!(flags & MSG_CMSG_COMPAT); + + /* + * If this skb has a frag_list, then here that means that + * we will have to use the frag_list skb for compat tasks + * and the regular skb for non-compat tasks. + * + * The skb might (and likely will) be cloned, so we can't + * just reset frag_list and go on with things -- we need to + * keep that. For the compat case that's easy -- simply get + * a reference to the compat skb and free the regular one + * including the frag. For the non-compat case, we need to + * avoid sending the frag to the user -- so assign NULL but + * restore it below before freeing the skb. + */ + if (need_compat) { + struct sk_buff *compskb = skb_shinfo(skb)->frag_list; + skb_get(compskb); + kfree_skb(skb); + skb = compskb; + } else { + frag = skb_shinfo(skb)->frag_list; + skb_shinfo(skb)->frag_list = NULL; + } + } +#endif + msg->msg_namelen = 0; copied = skb->len; @@ -1403,6 +1432,11 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, siocb->scm->creds = *NETLINK_CREDS(skb); if (flags & MSG_TRUNC) copied = skb->len; + +#ifdef CONFIG_COMPAT_NETLINK_MESSAGES + skb_shinfo(skb)->frag_list = frag; +#endif + skb_free_datagram(sk, skb); if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) diff --git a/net/wireless/wext.c b/net/wireless/wext.c index ee35e64..3fe3c2c 100644 --- a/net/wireless/wext.c +++ b/net/wireless/wext.c @@ -417,6 +417,21 @@ static const int event_type_size[] = { IW_EV_QUAL_LEN, /* IW_HEADER_TYPE_QUAL */ }; +#ifdef CONFIG_COMPAT +static const int compat_event_type_size[] = { + IW_EV_COMPAT_LCP_LEN, /* IW_HEADER_TYPE_NULL */ + 0, + IW_EV_COMPAT_CHAR_LEN, /* IW_HEADER_TYPE_CHAR */ + 0, + IW_EV_COMPAT_UINT_LEN, /* IW_HEADER_TYPE_UINT */ + IW_EV_COMPAT_FREQ_LEN, /* IW_HEADER_TYPE_FREQ */ + IW_EV_COMPAT_ADDR_LEN, /* IW_HEADER_TYPE_ADDR */ + 0, + IW_EV_COMPAT_POINT_LEN, /* Without variable payload */ + IW_EV_COMPAT_PARAM_LEN, /* IW_HEADER_TYPE_PARAM */ + IW_EV_COMPAT_QUAL_LEN, /* IW_HEADER_TYPE_QUAL */ +}; +#endif /************************ COMMON SUBROUTINES ************************/ /* @@ -1348,6 +1363,22 @@ void wireless_send_event(struct net_device * dev, struct sk_buff *skb; struct nlmsghdr *nlh; struct nlattr *nla; +#ifdef CONFIG_COMPAT + struct __compat_iw_event *compat_event; + struct compat_iw_point compat_wrqu; + struct sk_buff *compskb; +#endif + + /* + * Nothing in the kernel sends scan events with data, be safe. + * This is necessary because we cannot fix up scan event data + * for compat, due to being contained in 'extra', but normally + * applications are required to retrieve the scan data anyway + * and no data is included in the event, this codifies that + * practice. + */ + if (WARN_ON(cmd == SIOCGIWSCAN && extra)) + extra = NULL; /* Get the description of the Event */ if (cmd <= SIOCIWLAST) { @@ -1446,7 +1477,54 @@ void wireless_send_event(struct net_device * dev, memcpy(((char *) event) + hdr_len, extra, extra_len); nlmsg_end(skb, nlh); +#ifdef CONFIG_COMPAT + hdr_len = compat_event_type_size[descr->header_type]; + event_len = hdr_len + extra_len; + compskb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); + if (!compskb) { + kfree_skb(skb); + return; + } + + /* Send via the RtNetlink event channel */ + nlh = rtnetlink_ifinfo_prep(dev, compskb); + if (WARN_ON(!nlh)) { + kfree_skb(skb); + kfree_skb(compskb); + return; + } + + /* Add the wireless events in the netlink packet */ + nla = nla_reserve(compskb, IFLA_WIRELESS, event_len); + if (!nla) { + kfree_skb(skb); + kfree_skb(compskb); + return; + } + compat_event = nla_data(nla); + + compat_event->len = event_len; + compat_event->cmd = cmd; + if (descr->header_type == IW_HEADER_TYPE_POINT) { + compat_wrqu.length = wrqu->data.length; + compat_wrqu.flags = wrqu->data.flags; + memcpy(&compat_event->pointer, + ((char *) &compat_wrqu) + IW_EV_COMPAT_POINT_OFF, + hdr_len - IW_EV_COMPAT_LCP_LEN); + if (extra_len) + memcpy(((char *) compat_event) + hdr_len, + extra, extra_len); + } else { + /* extra_len must be zero, so no if (extra) needed */ + memcpy(&compat_event->pointer, wrqu, + hdr_len - IW_EV_COMPAT_LCP_LEN); + } + + nlmsg_end(compskb, nlh); + + skb_shinfo(skb)->frag_list = compskb; +#endif skb_queue_tail(&dev_net(dev)->wext_nlevents, skb); schedule_work(&wireless_nlevent_work); } |