linux-toradex.git/net/decnet/dn_route.c, branch v4.0-rc1

netlink: Fix bugs in nlmsg_end() conversions.

2015-01-19T04:36:08+00:00

Commit 053c095a82cf ("netlink: make nlmsg_end() and genlmsg_end()
void") didn't catch all of the cases where callers were breaking out
on the return value being equal to zero, which they no longer should
when zero means success.

Fix all such cases.

Reported-by: Marcel Holtmann 
Reported-by: Scott Feldman 
Signed-off-by: David S. Miller

netlink: make nlmsg_end() and genlmsg_end() void

2015-01-18T06:03:45+00:00

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 
Signed-off-by: David S. Miller

ipv4: add a sock pointer to dst->output() path.

2014-04-15T17:47:15+00:00

In the dst->output() path for ipv4, the code assumes the skb it has to
transmit is attached to an inet socket, specifically via
ip_mc_output() : The sk_mc_loop() test triggers a WARN_ON() when the
provider of the packet is an AF_PACKET socket.

The dst->output() method gets an additional 'struct sock *sk'
parameter. This needs a cascade of changes so that this parameter can
be propagated from vxlan to final consumer.

Fixes: 8f646c922d55 ("vxlan: keep original skb ownership")
Reported-by: lucien xin 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

decnet: use __dev_get_by_index instead of dev_get_by_index to find interface

2014-01-15T02:50:46+00:00

The following call chain we can identify that dn_cache_getroute() is
protected under rtnl_lock. So if we use __dev_get_by_index() instead
of dev_get_by_index() to find interface handlers in it, this would help
us avoid to change interface reference counter.

rtnetlink_rcv()
  rtnl_lock()
    netlink_rcv_skb()
      dn_cache_getroute()
  rtnl_unlock()

Signed-off-by: Ying Xue 
Signed-off-by: David S. Miller

net: Remove FLOWI_FLAG_CAN_SLEEP

2013-12-06T06:24:39+00:00

FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility
to sleep until the needed states are resolved. This code is gone,
so FLOWI_FLAG_CAN_SLEEP is not needed anymore.

Signed-off-by: Steffen Klassert

decnet: Move rtm_dn_policy to dn_route to make it available if !CONFIG_DECNET_ROUTER

2013-03-22T16:51:59+00:00

Otherwise build fails with CONFIG_DECNET && !CONFIG_DECNET_ROUTER

Reported-by: kbuild test robot 
Signed-off-by: Thomas Graf 
Signed-off-by: David S. Miller

rtnetlink: Remove passing of attributes into rtnl_doit functions

2013-03-22T14:31:16+00:00

With decnet converted, we can finally get rid of rta_buf and its
computations around it. It also gets rid of the minimal header
length verification since all message handlers do that explicitly
anyway.

Signed-off-by: Thomas Graf 
Signed-off-by: David S. Miller

decnet: Parse netlink attributes on our own

2013-03-22T14:31:16+00:00

decnet is the only subsystem left that is relying on the global
netlink attribute buffer rta_buf. It's horrible design and we
want to get rid of it.

This converts all of decnet to do implicit attribute parsing. It
also gets rid of the error prone struct dn_kern_rta.

Yes, the fib_magic() stuff is not pretty.

It's compiled tested but I need someone with appropriate hardware
to test the patch since I don't have access to it.

Cc: linux-decnet-user@lists.sourceforge.net
Signed-off-by: Thomas Graf 
Signed-off-by: David S. Miller

net: proc: change proc_net_remove to remove_proc_entry

2013-02-18T19:53:08+00:00

proc_net_remove is only used to remove proc entries
that under /proc/net,it's not a general function for
removing proc entries of netns. if we want to remove
some proc entries which under /proc/net/stat/, we still
need to call remove_proc_entry.

this patch use remove_proc_entry to replace proc_net_remove.
we can remove proc_net_remove after this patch.

Signed-off-by: Gao feng 
Signed-off-by: David S. Miller

net: proc: change proc_net_fops_create to proc_create

2013-02-18T19:53:08+00:00

Right now, some modules such as bonding use proc_create
to create proc entries under /proc/net/, and other modules
such as ipv4 use proc_net_fops_create.

It looks a little chaos.this patch changes all of
proc_net_fops_create to proc_create. we can remove
proc_net_fops_create after this patch.

Signed-off-by: Gao feng 
Signed-off-by: David S. Miller