Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6

[safe/jmp/linux-2.6] / net / netlink / af_netlink.c

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 5b33879..b73d4e6 100644 (file)
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -85,6 +85,7 @@ struct netlink_sock {
 
 #define NETLINK_KERNEL_SOCKET  0x1
 #define NETLINK_RECV_PKTINFO   0x2
+#define NETLINK_BROADCAST_SEND_ERROR   0x4
 
 static inline struct netlink_sock *nlk_sk(struct sock *sk)
 {
@@ -995,12 +996,15 @@ static inline int do_one_broadcast(struct sock *sk,
                netlink_overrun(sk);
                /* Clone failed. Notify ALL listeners. */
                p->failure = 1;
+               if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
+                       p->delivery_failure = 1;
        } else if (sk_filter(sk, p->skb2)) {
                kfree_skb(p->skb2);
                p->skb2 = NULL;
        } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) {
                netlink_overrun(sk);
-               p->delivery_failure = 1;
+               if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
+                       p->delivery_failure = 1;
        } else {
                p->congested |= val;
                p->delivered = 1;
@@ -1045,10 +1049,9 @@ int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
 
        netlink_unlock_table();
 
-       if (info.skb2)
-               kfree_skb(info.skb2);
+       kfree_skb(info.skb2);
 
-       if (info.delivery_failure || info.failure)
+       if (info.delivery_failure)
                return -ENOBUFS;
 
        if (info.delivered) {
@@ -1088,6 +1091,13 @@ out:
        return 0;
 }
 
+/**
+ * netlink_set_err - report error to broadcast listeners
+ * @ssk: the kernel netlink socket, as returned by netlink_kernel_create()
+ * @pid: the PID of a process that we want to skip (if any)
+ * @groups: the broadcast group that will notice the error
+ * @code: error code, must be negative (as usual in kernelspace)
+ */
 void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
 {
        struct netlink_set_err_data info;
@@ -1097,7 +1107,8 @@ void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
        info.exclude_sk = ssk;
        info.pid = pid;
        info.group = group;
-       info.code = code;
+       /* sk->sk_err wants a positive error value */
+       info.code = -code;
 
        read_lock(&nl_table_lock);
 
@@ -1164,6 +1175,13 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
                err = 0;
                break;
        }
+       case NETLINK_BROADCAST_ERROR:
+               if (val)
+                       nlk->flags |= NETLINK_BROADCAST_SEND_ERROR;
+               else
+                       nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR;
+               err = 0;
+               break;
        default:
                err = -ENOPROTOOPT;
        }
@@ -1196,6 +1214,16 @@ static int netlink_getsockopt(struct socket *sock, int level, int optname,
                        return -EFAULT;
                err = 0;
                break;
+       case NETLINK_BROADCAST_ERROR:
+               if (len < sizeof(int))
+                       return -EINVAL;
+               len = sizeof(int);
+               val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0;
+               if (put_user(len, optlen) ||
+                   put_user(val, optval))
+                       return -EFAULT;
+               err = 0;
+               break;
        default:
                err = -ENOPROTOOPT;
        }
@@ -1522,8 +1550,7 @@ EXPORT_SYMBOL(netlink_set_nonroot);
 
 static void netlink_destroy_callback(struct netlink_callback *cb)
 {
-       if (cb->skb)
-               kfree_skb(cb->skb);
+       kfree_skb(cb->skb);
        kfree(cb);
 }
 
@@ -1740,12 +1767,18 @@ int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid,
                        exclude_pid = pid;
                }
 
-               /* errors reported via destination sk->sk_err */
-               nlmsg_multicast(sk, skb, exclude_pid, group, flags);
+               /* errors reported via destination sk->sk_err, but propagate
+                * delivery errors if NETLINK_BROADCAST_ERROR flag is set */
+               err = nlmsg_multicast(sk, skb, exclude_pid, group, flags);
        }
 
-       if (report)
-               err = nlmsg_unicast(sk, skb, pid);
+       if (report) {
+               int err2;
+
+               err2 = nlmsg_unicast(sk, skb, pid);
+               if (!err || err == -ESRCH)
+                       err = err2;
+       }
 
        return err;
 }