linux.git/net/core, branch v3.13-rc5

neigh: Netlink notification for administrative NUD state change

2013-12-17T21:14:35+00:00

The neighbour code sends up an RTM_NEWNEIGH netlink notification if
the NUD state of a neighbour cache entry is changed by a timer (e.g.
from REACHABLE to STALE), even if the lladdr of the entry has not
changed.

But an administrative change to the the NUD state of a neighbour cache
entry that does not change the lladdr (e.g. via "ip -4 neigh change
...  nud ...") does not trigger a netlink notification.  This means
that netlink listeners will not hear about administrative NUD state
changes such as from a resolved state to PERMANENT.

This patch changes the neighbor code to generate an RTM_NEWNEIGH
message when the NUD state of an entry is changed administratively.

Signed-off-by: Bob Gilligan 
Acked-by: Nicolas Dichtel 
Signed-off-by: David S. Miller

net: unix: allow set_peek_off to fail

2013-12-11T02:45:15+00:00

unix_dgram_recvmsg() will hold the readlock of the socket until recv
is complete.

In the same time, we may try to setsockopt(SO_PEEK_OFF) which will hang until
unix_dgram_recvmsg() will complete (which can take a while) without allowing
us to break out of it, triggering a hung task spew.

Instead, allow set_peek_off to fail, this way userspace will not hang.

Signed-off-by: Sasha Levin 
Acked-by: Pavel Emelyanov 
Signed-off-by: David S. Miller

net: drop_monitor: fix the value of maxattr

2013-12-10T02:10:38+00:00

maxattr in genl_family should be used to save the max attribute
type, but not the max command type. Drop monitor doesn't support
any attributes, so we should leave it as zero.

Signed-off-by: David S. Miller

net: clear local_df when passing skb between namespaces

2013-12-06T04:42:38+00:00

We must clear local_df when passing the skb between namespaces as the
packet is not local to the new namespace any more and thus may not get
fragmented by local rules. Fred Templin noticed that other namespaces
do fragment IPv6 packets while forwarding. Instead they should have send
back a PTB.

The same problem should be present when forwarding DF-IPv4 packets
between namespaces.

Reported-by: Templin, Fred L 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

{pktgen, xfrm} Update IPv4 header total len and checksum after tranformation

2013-12-02T01:33:52+00:00

commit a553e4a6317b2cfc7659542c10fe43184ffe53da ("[PKTGEN]: IPSEC support")
tried to support IPsec ESP transport transformation for pktgen, but acctually
this doesn't work at all for two reasons(The orignal transformed packet has
bad IPv4 checksum value, as well as wrong auth value, reported by wireshark)

- After transpormation, IPv4 header total length needs update,
  because encrypted payload's length is NOT same as that of plain text.

- After transformation, IPv4 checksum needs re-caculate because of payload
  has been changed.

With this patch, armmed pktgen with below cofiguration, Wireshark is able to
decrypted ESP packet generated by pktgen without any IPv4 checksum error or
auth value error.

pgset "flag IPSEC"
pgset "flows 1"

Signed-off-by: Fan Du 
Signed-off-by: David S. Miller

gso: handle new frag_list of frags GRO packets

2013-11-21T19:11:50+00:00

Recently GRO started generating packets with frag_lists of frags.
This was not handled by GSO, thus leading to a crash.

Thankfully these packets are of a regular form and are easy to
handle.  This patch handles them in two ways.  For completely
non-linear frag_list entries, we simply continue to iterate over
the frag_list frags once we exhaust the normal frags.  For frag_list
entries with linear parts, we call pskb_trim on the first part
of the frag_list skb, and then process the rest of the frags in
the usual way.

This patch also kills a chunk of dead frag_list code that has
obviously never ever been run since it ends up generating a bogus
GSO-segmented packet with a frag_list entry.

Future work is planned to split super big packets into TSO
ones.

Fixes: 8a29111c7ca6 ("net: gro: allow to build full sized skb")
Reported-by: Christoph Paasch 
Reported-by: Jerry Chu 
Reported-by: Sander Eikelenboom 
Signed-off-by: Herbert Xu 
Signed-off-by: Eric Dumazet 
Tested-by: Sander Eikelenboom 
Tested-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: rework recvmsg handler msg_name and msg_namelen logic

2013-11-21T02:52:30+00:00

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller 
Suggested-by: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

net: core: Always propagate flag changes to interfaces

2013-11-20T20:29:56+00:00

The following commit:
    b6c40d68ff6498b7f63ddf97cf0aa818d748dee7
    net: only invoke dev->change_rx_flags when device is UP

tried to fix a problem with VLAN devices and promiscuouse flag setting.
The issue was that VLAN device was setting a flag on an interface that
was down, thus resulting in bad promiscuity count.
This commit blocked flag propagation to any device that is currently
down.

A later commit:
    deede2fabe24e00bd7e246eb81cd5767dc6fcfc7
    vlan: Don't propagate flag changes on down interfaces

fixed VLAN code to only propagate flags when the VLAN interface is up,
thus fixing the same issue as above, only localized to VLAN.

The problem we have now is that if we have create a complex stack
involving multiple software devices like bridges, bonds, and vlans,
then it is possible that the flags would not propagate properly to
the physical devices.  A simple examle of the scenario is the
following:

  eth0----> bond0 ----> bridge0 ---> vlan50

If bond0 or eth0 happen to be down at the time bond0 is added to
the bridge, then eth0 will never have promisc mode set which is
currently required for operation as part of the bridge.  As a
result, packets with vlan50 will be dropped by the interface.

The only 2 devices that implement the special flag handling are
VLAN and DSA and they both have required code to prevent incorrect
flag propagation.  As a result we can remove the generic solution
introduced in b6c40d68ff6498b7f63ddf97cf0aa818d748dee7 and leave
it to the individual devices to decide whether they will block
flag propagation or not.

Reported-by: Stefan Priebe 
Suggested-by: Veaceslav Falico 
Signed-off-by: Vlad Yasevich 
Signed-off-by: David S. Miller

genetlink: make multicast groups const, prevent abuse

2013-11-19T21:39:06+00:00

Register generic netlink multicast groups as an array with
the family and give them contiguous group IDs. Then instead
of passing the global group ID to the various functions that
send messages, pass the ID relative to the family - for most
families that's just 0 because the only have one group.

This avoids the list_head and ID in each group, adding a new
field for the mcast group ID offset to the family.

At the same time, this allows us to prevent abusing groups
again like the quota and dropmon code did, since we can now
check that a family only uses a group it owns.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

genetlink: pass family to functions using groups

2013-11-19T21:39:06+00:00

This doesn't really change anything, but prepares for the
next patch that will change the APIs to pass the group ID
within the family, rather than the global group ID.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller