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>
As reported by Toralf Förster and Randy Dunlap.
- http://linuxwimax.org/pipermail/wimax/2009-January/000460.html
- http://lkml.org/lkml/2009/1/29/279
The definitions needed for the wimax stack and i2400m driver debug
infrastructure was, by mistake, compiled depending on CONFIG_DEBUG_FS
(by them being placed in the debugfs.c files); thus the build broke in
2.6.29-rc3 when debugging was enabled (CONFIG_WIMAX_DEBUG) and
DEBUG_FS was disabled.
These definitions are always needed if debug is enabled at compile
time (independently of DEBUG_FS being or not enabled), so moving them
to a file that is always compiled fixes the issue.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implements the basic life cycles of a 'struct wimax_dev', some common
generic netlink functionality for marshalling calls to user space,
and the device state machine.
For looking up net devices based on their generic netlink family IDs,
use a low overhead method that optimizes for the case where most
systems have a single WiMAX device, or at most, a very low number of
WiMAX adaptors.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
