The returned net_namespace of batadv_getlink_net may be used with functions
that potentially modify the struct. Thus it must return the pointer as
non-const like rtnl_link_ops::get_link_net does.
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
An unicast batman-adv packet cannot be transmitted to a multicast or zero
mac address. So reject incoming packets which still have these classes of
addresses as destination mac address in the outer ethernet header.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The routing check for management frames is validating the source mac
address in the outer ethernet header. It rejects every source mac address
which is a broadcast address. But it also has to reject the zero-mac
address and multicast mac addresses.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The routing checks are validating the source mac address of the outer
ethernet header. They reject every source mac address which is a broadcast
address. But they also have to reject any multicast mac addresses.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
[sw@simonwunderlich.de: fix commit message typo]
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
No caller of batadv_send_skb_to_orig is expecting the results to be -1
(-EPERM) anymore when the skbuff was not consumed. They will instead expect
that the skbuff is always consumed. Having such return code filter is
therefore not needed anymore.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Receiving functions in Linux consume the supplied skbuff. Doing the same in
the batadv_rx_handler functions makes the behavior more similar to the rest
of the Linux network code.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Sending functions in Linux consume the supplied skbuff. Doing the same in
batadv_send_skb_to_orig avoids the hack of returning -1 (-EPERM) to signal
the caller that he is responsible for cleaning up the skb.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Sending functions in Linux consume the supplied skbuff. Doing the same in
batadv_frag_send_packet avoids the hack of returning -1 (-EPERM) to signal
the caller that he is responsible for cleaning up the skb.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
A failure during the submission also causes dropped packets.
batadv_interface_tx should therefore also increase the DROPPED counter for
these returns.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
kfree_skb assumes that an skb is dropped after an failure and notes that.
consume_skb should be used in non-failure situations. Such information is
important for dropmonitor netlink which tells how many packets were dropped
and where this drop happened.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
With this patch, (re)broadcasting on a specific interfaces is avoided:
* No neighbor: There is no need to broadcast on an interface if there
is no node behind it.
* Single neighbor is source: If there is just one neighbor on an
interface and if this neighbor is the one we actually got this
broadcast packet from, then we do not need to echo it back.
* Single neighbor is originator: If there is just one neighbor on
an interface and if this neighbor is the originator of this
broadcast packet, then we do not need to echo it back.
Goodies for BATMAN V:
("Upgrade your BATMAN IV network to V now to get these for free!")
Thanks to the split of OGMv1 into two packet types, OGMv2 and ELP
that is, we can now apply the same optimizations stated above to OGMv2
packets, too.
Furthermore, with BATMAN V, rebroadcasts can be reduced in certain
multi interface cases, too, where BATMAN IV cannot. This is thanks to
the removal of the "secondary interface originator" concept in BATMAN V.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Instead of latching onto the OGM period, this patch introduces a worker
dedicated to multicast TT and TVLV updates.
The reasoning is, that upon roaming especially the translation table
should be updated timely to minimize connectivity issues.
With BATMAN V, the idea is to greatly increase the OGM interval to
reduce overhead. Unfortunately, right now this could lead to
a bad user experience if multicast traffic is involved.
Therefore this patch introduces a fixed 500ms update interval for
multicast TT entries and the multicast TVLV.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
During broadcast queueing, the skb_reset_mac_header() sets the skb
to a place invalid for a MAC header, pointing right into the
batman-adv broadcast packet. Luckily, no one seems to actually use
eth_hdr(skb) afterwards until batadv_send_skb_packet() resets the
header to a valid position again.
Therefore removing this unnecessary, weird skb_reset_mac_header()
call.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
batadv_mcast_mla_list_free() just frees some leftovers of a local feast
in batadv_mcast_mla_update(). No lockdep needed as it has nothing to do
with bat_priv->mcast.mla_list.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The genl_ops don't need to be written by anyone and thus can be moved in a
ro memory range.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Fixes: 56989f6d85 ("genetlink: mark families as __ro_after_init")
Fixes: 2ae0f17df1 ("genetlink: use idr to track families")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
order):
- bump version strings, by Simon Wunderlich
- README updates/clean up, by Sven Eckelmann (4 patches)
- Code clean up and restructuring by Sven Eckelmann (2 patches)
- Kerneldoc fix in forw_packet structure, by Linus Luessing
- Remove unused argument in dbg_arp, by Antonio Quartulli
- Add support to build batman-adv without wireless, by Linus Luessing
- Restructure error handling for is_ap_isolated, by Markus Elfring
- Remove unused initialization in various functions, by Sven Eckelmann
- Use better names for fragment and gateway list heads, by Sven
Eckelmann (2 patches)
- Convert to octal permissions for files, by Sven Eckelmann
- Avoid precedence issues for some macros, by Sven Eckelmann
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Merge tag 'batadv-next-for-davem-20161027' of git://git.open-mesh.org/linux-merge
Simon Wunderlich says:
====================
This code cleanup patchset includes the following changes (chronological
order):
- bump version strings, by Simon Wunderlich
- README updates/clean up, by Sven Eckelmann (4 patches)
- Code clean up and restructuring by Sven Eckelmann (2 patches)
- Kerneldoc fix in forw_packet structure, by Linus Luessing
- Remove unused argument in dbg_arp, by Antonio Quartulli
- Add support to build batman-adv without wireless, by Linus Luessing
- Restructure error handling for is_ap_isolated, by Markus Elfring
- Remove unused initialization in various functions, by Sven Eckelmann
- Use better names for fragment and gateway list heads, by Sven
Eckelmann (2 patches)
- Convert to octal permissions for files, by Sven Eckelmann
- Avoid precedence issues for some macros, by Sven Eckelmann
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Now genl_register_family() is the only thing (other than the
users themselves, perhaps, but I didn't find any doing that)
writing to the family struct.
In all families that I found, genl_register_family() is only
called from __init functions (some indirectly, in which case
I've add __init annotations to clarifly things), so all can
actually be marked __ro_after_init.
This protects the data structure from accidental corruption.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of providing macros/inline functions to initialize
the families, make all users initialize them statically and
get rid of the macros.
This reduces the kernel code size by about 1.6k on x86-64
(with allyesconfig).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Static family IDs have never really been used, the only
use case was the workaround I introduced for those users
that assumed their family ID was also their multicast
group ID.
Additionally, because static family IDs would never be
reserved by the generic netlink code, using a relatively
low ID would only work for built-in families that can be
registered immediately after generic netlink is started,
which is basically only the control family (apart from
the workaround code, which I also had to add code for so
it would reserve those IDs)
Thus, anything other than GENL_ID_GENERATE is flawed and
luckily not used except in the cases I mentioned. Move
those workarounds into a few lines of code, and then get
rid of GENL_ID_GENERATE entirely, making it more robust.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The maximum MTU is defined via the slave devices of an batman-adv
interface. Thus it is not possible to calculate the max_mtu during the
creation of the batman-adv device when no slave devices are attached. Doing
so would for example break non-fragmentation setups which then
(incorrectly) allow an MTU of 1500 even when underlying device cannot
transport 1500 bytes + batman-adv headers.
Checking the dynamically calculated max_mtu via the minimum of the slave
devices MTU during .ndo_change_mtu is also used by the bridge interface.
Cc: Jarod Wilson <jarod@redhat.com>
Fixes: b3e3893e12 ("net: use core MTU range checking in misc drivers")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
firewire-net:
- set min/max_mtu
- remove fwnet_change_mtu
nes:
- set max_mtu
- clean up nes_netdev_change_mtu
xpnet:
- set min/max_mtu
- remove xpnet_dev_change_mtu
hippi:
- set min/max_mtu
- remove hippi_change_mtu
batman-adv:
- set max_mtu
- remove batadv_interface_change_mtu
- initialization is a little async, not 100% certain that max_mtu is set
in the optimal place, don't have hardware to test with
rionet:
- set min/max_mtu
- remove rionet_change_mtu
slip:
- set min/max_mtu
- streamline sl_change_mtu
um/net_kern:
- remove pointless ndo_change_mtu
hsi/clients/ssi_protocol:
- use core MTU range checking
- remove now redundant ssip_pn_set_mtu
ipoib:
- set a default max MTU value
- Note: ipoib's actual max MTU can vary, depending on if the device is in
connected mode or not, so we'll just set the max_mtu value to the max
possible, and let the ndo_change_mtu function continue to validate any new
MTU change requests with checks for CM or not. Note that ipoib has no
min_mtu set, and thus, the network core's mtu > 0 check is the only lower
bounds here.
mptlan:
- use net core MTU range checking
- remove now redundant mpt_lan_change_mtu
fddi:
- min_mtu = 21, max_mtu = 4470
- remove now redundant fddi_change_mtu (including export)
fjes:
- min_mtu = 8192, max_mtu = 65536
- The max_mtu value is actually one over IP_MAX_MTU here, but the idea is to
get past the core net MTU range checks so fjes_change_mtu can validate a
new MTU against what it supports (see fjes_support_mtu in fjes_hw.c)
hsr:
- min_mtu = 0 (calls ether_setup, max_mtu is 1500)
f_phonet:
- min_mtu = 6, max_mtu = 65541
u_ether:
- min_mtu = 14, max_mtu = 15412
phonet/pep-gprs:
- min_mtu = 576, max_mtu = 65530
- remove redundant gprs_set_mtu
CC: netdev@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: Stefan Richter <stefanr@s5r6.in-berlin.de>
CC: Faisal Latif <faisal.latif@intel.com>
CC: linux-rdma@vger.kernel.org
CC: Cliff Whickman <cpw@sgi.com>
CC: Robin Holt <robinmholt@gmail.com>
CC: Jes Sorensen <jes@trained-monkey.org>
CC: Marek Lindner <mareklindner@neomailbox.ch>
CC: Simon Wunderlich <sw@simonwunderlich.de>
CC: Antonio Quartulli <a@unstable.cc>
CC: Sathya Prakash <sathya.prakash@broadcom.com>
CC: Chaitra P B <chaitra.basappa@broadcom.com>
CC: Suganath Prabu Subramani <suganath-prabu.subramani@broadcom.com>
CC: MPT-FusionLinux.pdl@broadcom.com
CC: Sebastian Reichel <sre@kernel.org>
CC: Felipe Balbi <balbi@kernel.org>
CC: Arvid Brodin <arvid.brodin@alten.se>
CC: Remi Denis-Courmont <courmisch@gmail.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It must be avoided that arguments to a macro are evaluated ungrouped (which
enforces normal operator precendence). Otherwise the result of the macro
is not well defined.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Linus prefers to have octal permission numbers instead of combinations of
macro names ("random line noise"). Also old existing "bad symbolic
permission bit macro use" should be converted to octal numbers.
(http://lkml.kernel.org/r/CA+55aFw5v23T-zvDZp-MmD_EYxF8WbafwwB59934FV7g21uMGQ@mail.gmail.com)
Also remove the S_IFREG bit from the octal representation because it is
filtered out by debugfs_create.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batman-adv codebase is using "list" for the list node (prev/next) and
<list content descriptor>+"_list" for the head of a list. Not using this
naming scheme can up in confusions when reading the code.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batman-adv codebase is using "list" for the list node (prev/next) and
<list content descriptor>+"_list" for the head of a list. Not using this
naming scheme can up in confusions because list_head is used for both the
head of the list and the list node (prev/next) in each item of the list.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Some variables are overwritten immediatelly in a functions. These don't
have to be initialized to a specific value on the stack because the value
will be overwritten before they will be used anywhere.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The variables "tt_local_entry" and "tt_global_entry" were eventually
checked again despite of a corresponding null pointer test before.
* Avoid this double check by reordering a function call sequence
and the better selection of jump targets.
* Omit the initialisation for these variables at the beginning then.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
With the new stub for cfg80211_get_station(), we can now build the
BATMAN V protocol even with a kernel that was built without any
wireless support.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The argument "type" passed to the batadv_dbg_arp() function is
never used. Remove it.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The forw_packet list node is wrongly attributed to the icmp socket code.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The function batadv_sum_counter is only used in soft-interface.c and has no
special relevance for main.h.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Kernel source files need not include <linux/kconfig.h> explicitly
because the top Makefile forces to include it with:
-include $(srctree)/include/linux/kconfig.h
This commit removes explicit includes except the following:
* arch/s390/include/asm/facilities_src.h
* tools/testing/radix-tree/linux/kernel.h
These two are used for host programs.
Link: http://lkml.kernel.org/r/1473656164-11929-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The skb_reserve() call only reserved headroom for the mac header, but
not the elp packet header itself.
Fixing this by using skb_put()'ing towards the skb tail instead of
skb_push()'ing towards the skb head.
Fixes: d6f94d91f7 ("batman-adv: ELP - adding basic infrastructure")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
batadv_find_router dereferences last_bonding_candidate from
orig_node without making sure that it has a valid reference. This reference
has to be retrieved by increasing the reference counter while holding
neigh_list_lock. The lock is required to avoid that
batadv_last_bonding_replace removes the current last_bonding_candidate,
reduces the reference counter and maybe destroys the object in this
process.
Fixes: f3b3d90189 ("batman-adv: add bonding again")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The files provided by batman-adv via debugfs are currently converted to
netlink. Tools which are not yet converted to use the netlink interface may
still rely on the old debugfs files. But systems which already upgraded
their tools can save some space by disabling this feature. The default
configuration of batman-adv on amd64 can reduce the size of the module by
around 11% when this feature is disabled.
$ size net/batman-adv/batman-adv.ko*
text data bss dec hex filename
150507 10395 4160 165062 284c6 net/batman-adv/batman-adv.ko.y
137106 7099 2112 146317 23b8d net/batman-adv/batman-adv.ko.n
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Switch-like virtual interfaces like bridge or openvswitch don't destroy
itself when all their attached netdevices dissappear. Instead they only
remove the link to the unregistered device and keep working until they get
removed manually.
This has the benefit that all configurations for this interfaces are kept
and daemons reacting to rtnl events can just add new slave interfaces
without going through the complete configuration of the switch-like
netdevice.
Handling unregister events of client devices similar in batman-adv allows
users to drop their current workaround of dummy netdevices attached to
batman-adv soft-interfaces.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
