Commit Graph

304 Commits

Author SHA1 Message Date
Dmitry Antipov
537db05da2 batman-adv: prefer kfree_rcu() over call_rcu() with free-only callbacks
Drop 'batadv_tt_local_entry_free_rcu()', 'batadv_tt_global_entry_free_rcu()'
and 'batadv_tt_orig_list_entry_free_rcu()' in favor of 'kfree_rcu()' in
'batadv_tt_local_entry_release()', 'batadv_tt_global_entry_release()' and
'batadv_tt_orig_list_entry_release()', respectively.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2024-03-29 20:18:21 +01:00
Remi Pommarel
d25ddb7e78 batman-adv: Fix TT global entry leak when client roamed back
When a client roamed back to a node before it got time to destroy the
pending local entry (i.e. within the same originator interval) the old
global one is directly removed from hash table and left as such.

But because this entry had an extra reference taken at lookup (i.e using
batadv_tt_global_hash_find) there is no way its memory will be reclaimed
at any time causing the following memory leak:

  unreferenced object 0xffff0000073c8000 (size 18560):
    comm "softirq", pid 0, jiffies 4294907738 (age 228.644s)
    hex dump (first 32 bytes):
      06 31 ac 12 c7 7a 05 00 01 00 00 00 00 00 00 00  .1...z..........
      2c ad be 08 00 80 ff ff 6c b6 be 08 00 80 ff ff  ,.......l.......
    backtrace:
      [<00000000ee6e0ffa>] kmem_cache_alloc+0x1b4/0x300
      [<000000000ff2fdbc>] batadv_tt_global_add+0x700/0xe20
      [<00000000443897c7>] _batadv_tt_update_changes+0x21c/0x790
      [<000000005dd90463>] batadv_tt_update_changes+0x3c/0x110
      [<00000000a2d7fc57>] batadv_tt_tvlv_unicast_handler_v1+0xafc/0xe10
      [<0000000011793f2a>] batadv_tvlv_containers_process+0x168/0x2b0
      [<00000000b7cbe2ef>] batadv_recv_unicast_tvlv+0xec/0x1f4
      [<0000000042aef1d8>] batadv_batman_skb_recv+0x25c/0x3a0
      [<00000000bbd8b0a2>] __netif_receive_skb_core.isra.0+0x7a8/0xe90
      [<000000004033d428>] __netif_receive_skb_one_core+0x64/0x74
      [<000000000f39a009>] __netif_receive_skb+0x48/0xe0
      [<00000000f2cd8888>] process_backlog+0x174/0x344
      [<00000000507d6564>] __napi_poll+0x58/0x1f4
      [<00000000b64ef9eb>] net_rx_action+0x504/0x590
      [<00000000056fa5e4>] _stext+0x1b8/0x418
      [<00000000878879d6>] run_ksoftirqd+0x74/0xa4
  unreferenced object 0xffff00000bae1a80 (size 56):
    comm "softirq", pid 0, jiffies 4294910888 (age 216.092s)
    hex dump (first 32 bytes):
      00 78 b1 0b 00 00 ff ff 0d 50 00 00 00 00 00 00  .x.......P......
      00 00 00 00 00 00 00 00 50 c8 3c 07 00 00 ff ff  ........P.<.....
    backtrace:
      [<00000000ee6e0ffa>] kmem_cache_alloc+0x1b4/0x300
      [<00000000d9aaa49e>] batadv_tt_global_add+0x53c/0xe20
      [<00000000443897c7>] _batadv_tt_update_changes+0x21c/0x790
      [<000000005dd90463>] batadv_tt_update_changes+0x3c/0x110
      [<00000000a2d7fc57>] batadv_tt_tvlv_unicast_handler_v1+0xafc/0xe10
      [<0000000011793f2a>] batadv_tvlv_containers_process+0x168/0x2b0
      [<00000000b7cbe2ef>] batadv_recv_unicast_tvlv+0xec/0x1f4
      [<0000000042aef1d8>] batadv_batman_skb_recv+0x25c/0x3a0
      [<00000000bbd8b0a2>] __netif_receive_skb_core.isra.0+0x7a8/0xe90
      [<000000004033d428>] __netif_receive_skb_one_core+0x64/0x74
      [<000000000f39a009>] __netif_receive_skb+0x48/0xe0
      [<00000000f2cd8888>] process_backlog+0x174/0x344
      [<00000000507d6564>] __napi_poll+0x58/0x1f4
      [<00000000b64ef9eb>] net_rx_action+0x504/0x590
      [<00000000056fa5e4>] _stext+0x1b8/0x418
      [<00000000878879d6>] run_ksoftirqd+0x74/0xa4

Releasing the extra reference from batadv_tt_global_hash_find even at
roam back when batadv_tt_global_free is called fixes this memory leak.

Cc: stable@vger.kernel.org
Fixes: 068ee6e204 ("batman-adv: roaming handling mechanism redesign")
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Signed-off-by; Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2023-08-05 08:02:01 +02:00
Linus Lüssing
0c4061c0d0 batman-adv: tvlv: prepare for tvlv enabled multicast packet type
Prepare TVLV infrastructure for more packet types, in particular the
upcoming batman-adv multicast packet type.

For that swap the OGM vs. unicast-tvlv packet boolean indicator to an
explicit unsigned integer packet type variable. And provide the skb
to a call to batadv_tvlv_containers_process(), as later the multicast
packet's TVLV handler will need to have access not only to the TVLV but
the full skb for forwarding. Forwarding will be invoked from the
multicast packet's TVLVs' contents later.

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>
2023-01-21 19:01:59 +01:00
Yu Zhe
8864d2fcf0 batman-adv: remove unnecessary type castings
remove unnecessary void* type castings.

Signed-off-by: Yu Zhe <yuzhe@nfschina.com>
[sven@narfation.org: Fix missing const in batadv_choose* functions]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2022-04-22 11:23:46 +02:00
Sven Eckelmann
eb7da4f17d batman-adv: Migrate to linux/container_of.h
The commit d2a8ebbf81 ("kernel.h: split out container_of() and
typeof_member() macros")  introduced a new header for the container_of
related macros from (previously) linux/kernel.h.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2022-03-02 09:00:13 +01:00
Pavel Skripkin
6f68cd6348 net: batman-adv: fix error handling
Syzbot reported ODEBUG warning in batadv_nc_mesh_free(). The problem was
in wrong error handling in batadv_mesh_init().

Before this patch batadv_mesh_init() was calling batadv_mesh_free() in case
of any batadv_*_init() calls failure. This approach may work well, when
there is some kind of indicator, which can tell which parts of batadv are
initialized; but there isn't any.

All written above lead to cleaning up uninitialized fields. Even if we hide
ODEBUG warning by initializing bat_priv->nc.work, syzbot was able to hit
GPF in batadv_nc_purge_paths(), because hash pointer in still NULL. [1]

To fix these bugs we can unwind batadv_*_init() calls one by one.
It is good approach for 2 reasons: 1) It fixes bugs on error handling
path 2) It improves the performance, since we won't call unneeded
batadv_*_free() functions.

So, this patch makes all batadv_*_init() clean up all allocated memory
before returning with an error to no call correspoing batadv_*_free()
and open-codes batadv_mesh_free() with proper order to avoid touching
uninitialized fields.

Link: https://lore.kernel.org/netdev/000000000000c87fbd05cef6bcb0@google.com/ [1]
Reported-and-tested-by: syzbot+28b0702ada0bf7381f58@syzkaller.appspotmail.com
Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-26 14:47:12 +01:00
Sven Eckelmann
79a0bffb83 batman-adv: Drop NULL check before dropping references
The check if a batman-adv related object is NULL or not is now directly in
the batadv_*_put functions. It is not needed anymore to perform this check
outside these function:

The changes were generated using a coccinelle semantic patch:

  @@
  expression E;
  @@
  - if (likely(E != NULL))
  (
  batadv_backbone_gw_put
  |
  batadv_claim_put
  |
  batadv_dat_entry_put
  |
  batadv_gw_node_put
  |
  batadv_hardif_neigh_put
  |
  batadv_hardif_put
  |
  batadv_nc_node_put
  |
  batadv_nc_path_put
  |
  batadv_neigh_ifinfo_put
  |
  batadv_neigh_node_put
  |
  batadv_orig_ifinfo_put
  |
  batadv_orig_node_put
  |
  batadv_orig_node_vlan_put
  |
  batadv_softif_vlan_put
  |
  batadv_tp_vars_put
  |
  batadv_tt_global_entry_put
  |
  batadv_tt_local_entry_put
  |
  batadv_tt_orig_list_entry_put
  |
  batadv_tt_req_node_put
  |
  batadv_tvlv_container_put
  |
  batadv_tvlv_handler_put
  )(E);

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2021-08-08 20:21:40 +02:00
Sven Eckelmann
6340dcbd61 batman-adv: Check ptr for NULL before reducing its refcnt
The commit b37a466837 ("netdevice: add the case if dev is NULL") changed
the way how the NULL check for net_devices have to be handled when trying
to reduce its reference counter. Before this commit, it was the
responsibility of the caller to check whether the object is NULL or not.
But it was changed to behave more like kfree. Now the callee has to handle
the NULL-case.

The batman-adv code was scanned via cocinelle for similar places. These
were changed to use the paradigm

  @@
  identifier E, T, R, C;
  identifier put;
  @@
   void put(struct T *E)
   {
  +	if (!E)
  +		return;
  	kref_put(&E->C, R);
   }

Functions which were used in other sources files were moved to the header
to allow the compiler to inline the NULL check and the kref_put call.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2021-08-08 20:21:40 +02:00
Yajun Deng
1160dfa178 net: Remove redundant if statements
The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05 13:27:50 +01:00
Tetsuo Handa
08c27f3322 batman-adv: initialize "struct batadv_tvlv_tt_vlan_data"->reserved field
KMSAN found uninitialized value at batadv_tt_prepare_tvlv_local_data()
[1], for commit ced72933a5 ("batman-adv: use CRC32C instead of CRC16
in TT code") inserted 'reserved' field into "struct batadv_tvlv_tt_data"
and commit 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN
specific") moved that field to "struct batadv_tvlv_tt_vlan_data" but left
that field uninitialized.

[1] https://syzkaller.appspot.com/bug?id=07f3e6dba96f0eb3cabab986adcd8a58b9bdbe9d

Reported-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com>
Tested-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: ced72933a5 ("batman-adv: use CRC32C instead of CRC16 in TT code")
Fixes: 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN specific")
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-05 15:06:03 -07:00
Sven Eckelmann
cfa55c6d47 batman-adv: Drop publication years from copyright info
The batman-adv source code was using the year of publication (to net-next)
as "last" year for the copyright statement. The whole source code mentioned
in the MAINTAINERS "BATMAN ADVANCED" section was handled as a single entity
regarding the publishing year.

This avoided having outdated (in sense of year information - not copyright
holder) publishing information inside several files. But since the simple
"update copyright year" commit (without other changes) in the file was not
well received in the upstream kernel, the option to not have a copyright
year (for initial and last publication) in the files are chosen instead.
More detailed information about the years can still be retrieved from the
SCM system.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2021-02-06 09:22:10 +01:00
Sven Eckelmann
aff6f5a68b batman-adv: Drop deprecated debugfs support
The debugfs support in batman-adv was marked as deprecated by the commit
00caf6a2b3 ("batman-adv: Mark debugfs functionality as deprecated") and
scheduled for removal in 2021.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-12-04 08:40:52 +01:00
Sven Eckelmann
bccb48c89f batman-adv: Fix typos and grammar in documentation
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-06-26 10:36:30 +02:00
Sven Eckelmann
3b2582c7af batman-adv: Avoid RCU list-traversal in spinlock
The new CONFIG_PROVE_RCU_LIST requires a condition statement in
(h)list_for_each_entry_rcu when the code might be executed in a non RCU
non-reader section with the writer lock. Otherwise lockdep might cause a
false positive warning like

  =============================
  WARNING: suspicious RCU usage
  -----------------------------
  translation-table.c:940 RCU-list traversed in non-reader section!!

batman-adv is (mostly) following the examples from the RCU documentation
and is using the normal list-traversal primitives instead of the RCU
list-traversal primitives when the writer (spin)lock is held.

The remaining users of RCU list-traversal primitives with writer spinlock
have to be converted to the same style as the rest of the code.

Reported-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-02-17 16:07:50 +01:00
Sven Eckelmann
68e039f966 batman-adv: Update copyright years for 2020
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-01-01 00:00:33 +01:00
Jeremy Sowden
17f78dd1bd batman-adv: fix for leaked TVLV handler.
A handler for BATADV_TVLV_ROAM was being registered when the
translation-table was initialized, but not unregistered when the
translation-table was freed.  Unregister it.

Fixes: 122edaa059 ("batman-adv: tvlv - convert roaming adv packet to use tvlv unicast packets")
Reported-by: syzbot+d454a826e670502484b8@syzkaller.appspotmail.com
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2019-05-21 23:01:24 +02:00
David S. Miller
f83f715195 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor comment merge conflict in mlx5.

Staging driver has a fixup due to the skb->xmit_more changes
in 'net-next', but was removed in 'net'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-05 14:14:19 -07:00
Linus Lüssing
32e727449c batman-adv: Add multicast-to-unicast support for multiple targets
With this patch multicast packets with a limited number of destinations
(current default: 16) will be split and transmitted by the originator as
individual unicast transmissions.

Wifi broadcasts with their low bitrate are still a costly undertaking.
In a mesh network this cost multiplies with the overall size of the mesh
network. Therefore using multiple unicast transmissions instead of
broadcast flooding is almost always less burdensome for the mesh
network.

The maximum amount of unicast packets can be configured via the newly
introduced multicast_fanout parameter. If this limit is exceeded
distribution will fall back to classic broadcast flooding.

The multicast-to-unicast conversion is performed on the initial
multicast sender node and counts on a final destination node, mesh-wide
basis (and not next hop, neighbor node basis).

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>
2019-03-25 10:01:13 +01:00
Sven Eckelmann
0d5f20c42b batman-adv: Drop license boilerplate
All files got a SPDX-License-Identifier with commit 7db7d9f369
("batman-adv: Add SPDX license identifier above copyright header"). All the
required information about the license conditions can be found in
LICENSES/.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2019-03-25 09:31:35 +01:00
Sven Eckelmann
f131a56880 batman-adv: Reduce tt_global hash refcnt only for removed entry
The batadv_hash_remove is a function which searches the hashtable for an
entry using a needle, a hashtable bucket selection function and a compare
function. It will lock the bucket list and delete an entry when the compare
function matches it with the needle. It returns the pointer to the
hlist_node which matches or NULL when no entry matches the needle.

The batadv_tt_global_free is not itself protected in anyway to avoid that
any other function is modifying the hashtable between the search for the
entry and the call to batadv_hash_remove. It can therefore happen that the
entry either doesn't exist anymore or an entry was deleted which is not the
same object as the needle. In such an situation, the reference counter (for
the reference stored in the hashtable) must not be reduced for the needle.
Instead the reference counter of the actually removed entry has to be
reduced.

Otherwise the reference counter will underflow and the object might be
freed before all its references were dropped. The kref helpers reported
this problem as:

  refcount_t: underflow; use-after-free.

Fixes: 7683fdc1e8 ("batman-adv: protect the local and the global trans-tables with rcu")
Reported-by: Martin Weinelt <martin@linuxlounge.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2019-03-25 09:31:19 +01:00
Sven Eckelmann
3d65b9acca batman-adv: Reduce tt_local hash refcnt only for removed entry
The batadv_hash_remove is a function which searches the hashtable for an
entry using a needle, a hashtable bucket selection function and a compare
function. It will lock the bucket list and delete an entry when the compare
function matches it with the needle. It returns the pointer to the
hlist_node which matches or NULL when no entry matches the needle.

The batadv_tt_local_remove is not itself protected in anyway to avoid that
any other function is modifying the hashtable between the search for the
entry and the call to batadv_hash_remove. It can therefore happen that the
entry either doesn't exist anymore or an entry was deleted which is not the
same object as the needle. In such an situation, the reference counter (for
the reference stored in the hashtable) must not be reduced for the needle.
Instead the reference counter of the actually removed entry has to be
reduced.

Otherwise the reference counter will underflow and the object might be
freed before all its references were dropped. The kref helpers reported
this problem as:

  refcount_t: underflow; use-after-free.

Fixes: ef72706a05 ("batman-adv: protect tt_local_entry from concurrent delete events")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2019-03-25 09:31:19 +01:00
Sven Eckelmann
7a79d717e0 batman-adv: Update copyright years for 2019
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2019-01-04 11:04:24 +01:00
Sven Eckelmann
6b7b40aad5 batman-adv: Add inconsistent local TT netlink dump detection
The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.

Commit 670dc2833d ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.

The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. The already existing
generation sequence counter from the hash helper can be used for this
simple hash.

Reported-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-11-12 10:41:51 +01:00
Sven Eckelmann
e7136e48ff batman-adv: Prevent duplicated global TT entry
The function batadv_tt_global_orig_entry_add is responsible for adding new
tt_orig_list_entry to the orig_list. It first checks whether the entry
already is in the list or not. If it is, then the creation of a new entry
is aborted.

But the lock for the list is only held when the list is really modified.
This could lead to duplicated entries because another context could create
an entry with the same key between the check and the list manipulation.

The check and the manipulation of the list must therefore be in the same
locked code section.

Fixes: d657e621a0 ("batman-adv: add reference counting for type batadv_tt_orig_list_entry")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-09-06 14:37:12 +02:00
Linus Lüssing
a44ebeff6b batman-adv: Fix multicast TT issues with bogus ROAM flags
When a (broken) node wrongly sends multicast TT entries with a ROAM
flag then this causes any receiving node to drop all entries for the
same multicast MAC address announced by other nodes, leading to
packet loss.

Fix this DoS vector by only storing TT sync flags. For multicast TT
non-sync'ing flag bits like ROAM are unused so far anyway.

Fixes: 1d8ab8d3c1 ("batman-adv: Modified forwarding behaviour for multicast packets")
Reported-by: Leonardo Mörlein <me@irrelefant.net>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-06-23 10:29:33 +02:00
Linus Lüssing
4a519b83da batman-adv: Avoid storing non-TT-sync flags on singular entries too
Since commit 54e22f265e ("batman-adv: fix TT sync flag inconsistencies")
TT sync flags and TT non-sync'd flags are supposed to be stored
separately.

The previous patch missed to apply this separation on a TT entry with
only a single TT orig entry.

This is a minor fix because with only a single TT orig entry the DDoS
issue the former patch solves does not apply.

Fixes: 54e22f265e ("batman-adv: fix TT sync flag inconsistencies")
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>
2018-06-23 10:29:33 +02:00
Marek Lindner
16116dac23 batman-adv: prevent TT request storms by not sending inconsistent TT TLVLs
A translation table TVLV changset sent with an OGM consists
of a number of headers (one per VLAN) plus the changeset
itself (addition and/or deletion of entries).

The per-VLAN headers are used by OGM recipients for consistency
checks. Said consistency check might determine that a full
translation table request is needed to restore consistency. If
the TT sender adds per-VLAN headers of empty VLANs into the OGM,
recipients are led to believe to have reached an inconsistent
state and thus request a full table update. The full table does
not contain empty VLANs (due to missing entries) the cycle
restarts when the next OGM is issued.

Consequently, when the translation table TVLV headers are
composed, empty VLANs are to be excluded.

Fixes: 21a57f6e7a3b ("batman-adv: make the TT CRC logic VLAN specific")
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-05-12 18:53:08 +02:00
Linus Lüssing
7072337e52 batman-adv: Fix TT sync flags for intermediate TT responses
The previous TT sync fix so far only fixed TT responses issued by the
target node directly. So far, TT responses issued by intermediate nodes
still lead to the wrong flags being added, leading to CRC mismatches.

This behaviour was observed at Freifunk Hannover in a 800 nodes setup
where a considerable amount of nodes were still infected with 'WI'
TT flags even with (most) nodes having the previous TT sync fix applied.

I was able to reproduce the issue with intermediate TT responses in a
four node test setup and this patch fixes this issue by ensuring to
use the per originator instead of the summarized, OR'd ones.

Fixes: e9c00136a4 ("batman-adv: fix tt_global_entries flags update")
Reported-by: Leonardo Mörlein <me@irrelefant.net>
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>
2018-05-12 18:52:19 +02:00
Sven Eckelmann
8ba0f9bd3b batman-adv: Avoid race in TT TVLV allocator helper
The functions batadv_tt_prepare_tvlv_local_data and
batadv_tt_prepare_tvlv_global_data are responsible for preparing a buffer
which can be used to store the TVLV container for TT and add the VLAN
information to it.

This will be done in three phases:

1. count the number of VLANs and their entries
2. allocate the buffer using the counters from the previous step and limits
   from the caller (parameter tt_len)
3. insert the VLAN information to the buffer

The step 1 and 3 operate on a list which contains the VLANs. The access to
these lists must be protected with an appropriate lock or otherwise they
might operate on on different entries. This could for example happen when
another context is adding VLAN entries to this list.

This could lead to a buffer overflow in these functions when enough entries
were added between step 1 and 3 to the VLAN lists that the buffer room for
the entries (*tt_change) is smaller then the now required extra buffer for
new VLAN entries.

Fixes: 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN specific")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-05-10 16:08:54 +02:00
Sven Eckelmann
6b1aea8cf2 batman-adv: Update copyright years for 2018
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-02-26 17:57:39 +01:00
Sven Eckelmann
fec149f5d3 batman-adv: Convert packet.h to uapi header
The header file is used by different userspace programs to inject packets
or to decode sniffed packets. It should therefore be available to them as
userspace header.

Also other components in the kernel (like the flow dissector) require
access to the packet definitions to be able to decode ETH_P_BATMAN ethernet
packets.

Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 15:35:53 -05:00
Sven Eckelmann
ff15c27c97 batman-adv: Add kernel-doc to externally visible functions
According to the kernel-doc documentation, externally visible functions
should be documented. This refers to all all non-static function which can
(and will) be used by functions in other sources files.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15 17:29:24 +01:00
Sven Eckelmann
7e9a8c2ce7 batman-adv: Use parentheses in function kernel-doc
The documentation describing kernel-doc comments for functions ("How to
format kernel-doc comments") uses parentheses at the end of the function
name. Using this format allows to use a consistent style when adding
documentation to a function and when referencing this function in a
different kernel-doc section.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15 17:29:20 +01:00
Sven Eckelmann
3a64469e4f batman-adv: Include net.h for net_ratelimited_function
The linux/net.h provides the net_ratelimited_function. It should
therefore be included directly before it is used.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15 17:29:17 +01:00
Sven Eckelmann
ecc36f5ee6 batman-adv: include build_bug.h for BUILD_BUG_ON define
commit bc6245e5ef ("bug: split BUILD_BUG stuff out into
<linux/build_bug.h>") added a new header for BUILD_BUG_ON. It should
therefore be included instead of linux/bug.h

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15 17:29:15 +01:00
Sven Eckelmann
b92b94ac73 batman-adv: include gfp.h for GFP_* defines
The linux/gfp.h provides the GFP_ATOMIC and GFP_KERNEL define. It should
therefore be included instead of linux/fs.h.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15 17:24:10 +01:00
Sven Eckelmann
7db7d9f369 batman-adv: Add SPDX license identifier above copyright header
The "Linux kernel licensing rules" require that each file has a SPDX
license identifier as first line (and sometimes as second line).

The FSFE REUSE practices [1] would also require the same tags but have no
restrictions on the placement in the source file. Using the "Linux kernel
licensing rules" is therefore also fulfilling the FSFE REUSE practices
requirements at the same time.

[1] https://reuse.software/practices/

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15 17:22:45 +01:00
Linus Lüssing
54e22f265e batman-adv: fix TT sync flag inconsistencies
This patch fixes an issue in the translation table code potentially
leading to a TT Request + Response storm. The issue may occur for nodes
involving BLA and an inconsistent configuration of the batman-adv AP
isolation feature. However, since the new multicast optimizations, a
single, malformed packet may lead to a mesh-wide, persistent
Denial-of-Service, too.

The issue occurs because nodes are currently OR-ing the TT sync flags of
all originators announcing a specific MAC address via the
translation table. When an intermediate node now receives a TT Request
and wants to answer this on behalf of the destination node, then this
intermediate node now responds with an altered flag field and broken
CRC. The next OGM of the real destination will lead to a CRC mismatch
and triggering a TT Request and Response again.

Furthermore, the OR-ing is currently never undone as long as at least
one originator announcing the according MAC address remains, leading to
the potential persistency of this issue.

This patch fixes this issue by storing the flags used in the CRC
calculation on a a per TT orig entry basis to be able to respond with
the correct, original flags in an intermediate TT Response for one
thing. And to be able to correctly unset sync flags once all nodes
announcing a sync flag vanish for another.

Fixes: e9c00136a4 ("batman-adv: fix tt_global_entries flags update")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Acked-by: Antonio Quartulli <a@unstable.cc>
[sw: typo in commit message]
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-07-31 11:17:38 +02:00
Simon Wunderlich
75ae84a4fe batman-adv: simplify return handling in some TT functions
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2017-06-09 15:57:00 +02:00
Simon Wunderlich
1227c9ae01 batman-adv: do not add loop detection mac addresses to global tt
This change has been made for local TT already, add another one for
global TT - but only for temporary entries (aka speedy join), to prevent
inconsistencies between local and global tables in case an older
batman-adv version is still announcing those entries from its local
table.

Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2017-06-09 15:56:59 +02:00
Sven Eckelmann
f7a2bd6544 batman-adv: Convert BATADV_PRINT_VID macro to function
The BATADV_PRINT_VID is not free of of possible side-effects. This can be
avoided when the the macro is converted to a simple inline function.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-03-16 21:14:53 +01:00
Sven Eckelmann
1fda4c0ac0 batman-adv: Fix unbalanced braces around else statement
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-03-16 21:14:51 +01:00
Sven Eckelmann
269cee6218 batman-adv: Remove unused variable in batadv_tt_local_set_flags
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-01-26 08:34:20 +01:00
Sven Eckelmann
ac79cbb96b batman-adv: update copyright years for 2017
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-01-26 08:34:19 +01:00
David S. Miller
c63d352f05 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-12-06 21:33:19 -05:00
Sven Eckelmann
c2d0f48a13 batman-adv: Check for alloc errors when preparing TT local data
batadv_tt_prepare_tvlv_local_data can fail to allocate the memory for the
new TVLV block. The caller is informed about this problem with the returned
length of 0. Not checking this value results in an invalid memory access
when either tt_data or tt_change is accessed.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN specific")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-12-02 10:46:59 +01:00
Sven Eckelmann
10b1bbb46c batman-adv: Cache the type of wifi device for each hardif
batman-adv is requiring the type of wifi device in different contexts. Some
of them can take the rtnl semaphore and some of them already have the
semaphore taken. But even others don't allow that the semaphore will be
taken.

The data has to be retrieved when the hardif is added to batman-adv because
some of the wifi information for an hardif will only be available with rtnl
lock. It can then be cached in the batadv_hard_iface and the functions
is_wifi_netdev and is_cfg80211_netdev can just compare the correct bits
without imposing extra locking requirements.

Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-11-08 19:02:37 +01:00
Linus Lüssing
cbebd363b2 batman-adv: Use own timer for multicast TT and TVLV updates
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>
2016-10-30 11:11:35 +01:00
Markus Elfring
393b299d2c batman-adv: Less function calls in batadv_is_ap_isolated() after error detection
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>
2016-10-18 15:02:43 +02:00
Sven Eckelmann
dc1cbd145e batman-adv: Allow to disable debugfs support
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>
2016-08-09 07:54:54 +02:00