path: root/net/wimax
diff options
authorPablo Neira Ayuso <pablo@netfilter.org>2009-02-05 23:56:36 -0800
committerDavid S. Miller <davem@davemloft.net>2009-02-05 23:56:36 -0800
commitff491a7334acfd74e515c896632e37e401f52676 (patch)
tree0e3663706a706029d6fc749ef7f66cdd03925231 /net/wimax
parent612e244c12215f6f74973ea3b89bff96450dc530 (diff)
netlink: change return-value logic of netlink_broadcast()
Currently, netlink_broadcast() reports errors to the caller if no messages at all were delivered: 1) If, at least, one message has been delivered correctly, returns 0. 2) Otherwise, if no messages at all were delivered due to skb_clone() failure, return -ENOBUFS. 3) Otherwise, if there are no listeners, return -ESRCH. With this patch, the caller knows if the delivery of any of the messages to the listeners have failed: 1) If it fails to deliver any message (for whatever reason), return -ENOBUFS. 2) Otherwise, if all messages were delivered OK, returns 0. 3) Otherwise, if no listeners, return -ESRCH. In the current ctnetlink code and in Netfilter in general, we can add reliable logging and connection tracking event delivery by dropping the packets whose events were not successfully delivered over Netlink. Of course, this option would be settable via /proc as this approach reduces performance (in terms of filtered connections per seconds by a stateful firewall) but providing reliable logging and event delivery (for conntrackd) in return. This patch also changes some clients of netlink_broadcast() that may report ENOBUFS errors via printk. This error handling is not of any help. Instead, the userspace daemons that are listening to those netlink messages should resync themselves with the kernel-side if they hit ENOBUFS. BTW, netlink_broadcast() clients include those that call cn_netlink_send(), nlmsg_multicast() and genlmsg_multicast() since they internally call netlink_broadcast() and return its error value. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/wimax')
2 files changed, 7 insertions, 14 deletions
diff --git a/net/wimax/op-msg.c b/net/wimax/op-msg.c
index cb3b4ad5368..5d149c1b5f0 100644
--- a/net/wimax/op-msg.c
+++ b/net/wimax/op-msg.c
@@ -258,7 +258,6 @@ EXPORT_SYMBOL_GPL(wimax_msg_len);
int wimax_msg_send(struct wimax_dev *wimax_dev, struct sk_buff *skb)
- int result;
struct device *dev = wimax_dev->net_dev->dev.parent;
void *msg = skb->data;
size_t size = skb->len;
@@ -266,11 +265,9 @@ int wimax_msg_send(struct wimax_dev *wimax_dev, struct sk_buff *skb)
d_printf(1, dev, "CTX: wimax msg, %zu bytes\n", size);
d_dump(2, dev, msg, size);
- result = genlmsg_multicast(skb, 0, wimax_gnl_mcg.id, GFP_KERNEL);
- d_printf(1, dev, "CTX: genl multicast result %d\n", result);
- if (result == -ESRCH) /* Nobody connected, ignore it */
- result = 0; /* btw, the skb is freed already */
- return result;
+ genlmsg_multicast(skb, 0, wimax_gnl_mcg.id, GFP_KERNEL);
+ d_printf(1, dev, "CTX: genl multicast done\n");
+ return 0;
diff --git a/net/wimax/stack.c b/net/wimax/stack.c
index 3869c032788..a0ee76b5251 100644
--- a/net/wimax/stack.c
+++ b/net/wimax/stack.c
@@ -163,16 +163,12 @@ int wimax_gnl_re_state_change_send(
struct device *dev = wimax_dev_to_dev(wimax_dev);
d_fnstart(3, dev, "(wimax_dev %p report_skb %p)\n",
wimax_dev, report_skb);
- if (report_skb == NULL)
+ if (report_skb == NULL) {
+ result = -ENOMEM;
goto out;
- genlmsg_end(report_skb, header);
- result = genlmsg_multicast(report_skb, 0, wimax_gnl_mcg.id, GFP_KERNEL);
- if (result == -ESRCH) /* Nobody connected, ignore it */
- result = 0; /* btw, the skb is freed already */
- if (result < 0) {
- dev_err(dev, "RE_STCH: Error sending: %d\n", result);
- nlmsg_free(report_skb);
+ genlmsg_end(report_skb, header);
+ genlmsg_multicast(report_skb, 0, wimax_gnl_mcg.id, GFP_KERNEL);
d_fnend(3, dev, "(wimax_dev %p report_skb %p) = %d\n",
wimax_dev, report_skb, result);