linux_dsm_epyc7002/net/bridge
Johannes Berg 053c095a82 netlink: make nlmsg_end() and genlmsg_end() void
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18 01:03:45 -05:00
..
netfilter net: rename vlan_tx_* helpers since "tx" is misleading there 2015-01-13 17:51:08 -05:00
br_device.c bridge: Add filtering support for default_pvid 2014-10-05 21:21:37 -04:00
br_fdb.c netlink: make nlmsg_end() and genlmsg_end() void 2015-01-18 01:03:45 -05:00
br_forward.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-11-01 14:53:27 -04:00
br_if.c bridge: Add ability to enable TSO 2015-01-12 16:18:09 -05:00
br_input.c bridge: only provide proxy ARP when CONFIG_INET is enabled 2015-01-14 15:08:02 -05:00
br_ioctl.c bridge: add space before '(/{', after ',', etc. 2013-12-19 19:27:26 -05:00
br_mdb.c netlink: make nlmsg_end() and genlmsg_end() void 2015-01-18 01:03:45 -05:00
br_multicast.c bridge: fix netfilter/NF_BR_LOCAL_OUT for own, locally generated queries 2014-11-17 12:38:02 +01:00
br_netfilter.c net: rename vlan_tx_* helpers since "tx" is misleading there 2015-01-13 17:51:08 -05:00
br_netlink.c netlink: make nlmsg_end() and genlmsg_end() void 2015-01-18 01:03:45 -05:00
br_nf_core.c netfilter: bridge: move br_netfilter out of the core 2014-09-26 18:42:31 +02:00
br_private_stp.h net: 8021q/bluetooth/bridge/can/ceph: Remove extern from function prototypes 2013-10-19 19:12:11 -04:00
br_private.h net: replace br_fdb_external_learn_* calls with switchdev notifier events 2015-01-18 00:23:57 -05:00
br_stp_bpdu.c br: fix use of ->rx_handler_data in code executed on non-rx_handler path 2013-12-06 15:41:40 -05:00
br_stp_if.c net: bridge: add a br_set_state helper function 2014-10-01 22:03:50 -04:00
br_stp_timer.c net: bridge: add a br_set_state helper function 2014-10-01 22:03:50 -04:00
br_stp.c bridge: call netdev_sw_port_stp_update when bridge port STP status changes 2014-12-02 20:01:22 -08:00
br_sysfs_br.c bridge: Add a default_pvid sysfs attribute 2014-10-05 21:21:36 -04:00
br_sysfs_if.c bridge: Add support for IEEE 802.11 Proxy ARP 2014-10-27 19:02:04 -04:00
br_vlan.c net: rename vlan_tx_* helpers since "tx" is misleading there 2015-01-13 17:51:08 -05:00
br.c net: replace br_fdb_external_learn_* calls with switchdev notifier events 2015-01-18 00:23:57 -05:00
Kconfig bridge: Add vlan filtering infrastructure 2013-02-13 19:41:46 -05:00
Makefile netfilter: bridge: build br_nf_core only if required 2014-09-30 14:07:51 -04:00