Commit Graph

366 Commits

Author SHA1 Message Date
Torsten Hilbrich
cdd14f25b1 vti6: Fix memory leak of skb if input policy check fails
commit 2a9de3af21aa8c31cd68b0b39330d69f8c1e59df upstream.

The vti6_rcv function performs some tests on the retrieved tunnel
including checking the IP protocol, the XFRM input policy, the
source and destination address.

In all but one places the skb is released in the error case. When
the input policy check fails the network packet is leaked.

Using the same goto-label discard in this case to fix this problem.

Fixes: ed1efb2aefbb ("ipv6: Add support for IPsec virtual tunnel interfaces")
Signed-off-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:24:31 +02:00
YueHaibing
7e36f70664 xfrm: policy: Fix doulbe free in xfrm_policy_timer
commit 4c59406ed00379c8663f8663d82b2537467ce9d7 upstream.

After xfrm_add_policy add a policy, its ref is 2, then

                             xfrm_policy_timer
                               read_lock
                               xp->walk.dead is 0
                               ....
                               mod_timer()
xfrm_policy_kill
  policy->walk.dead = 1
  ....
  del_timer(&policy->timer)
    xfrm_pol_put //ref is 1
  xfrm_pol_put  //ref is 0
    xfrm_policy_destroy
      call_rcu
                                 xfrm_pol_hold //ref is 1
                               read_unlock
                               xfrm_pol_put //ref is 0
                                 xfrm_policy_destroy
                                  call_rcu

xfrm_policy_destroy is called twice, which may leads to
double free.

Call Trace:
RIP: 0010:refcount_warn_saturate+0x161/0x210
...
 xfrm_policy_timer+0x522/0x600
 call_timer_fn+0x1b3/0x5e0
 ? __xfrm_decode_session+0x2990/0x2990
 ? msleep+0xb0/0xb0
 ? _raw_spin_unlock_irq+0x24/0x40
 ? __xfrm_decode_session+0x2990/0x2990
 ? __xfrm_decode_session+0x2990/0x2990
 run_timer_softirq+0x5c5/0x10e0

Fix this by use write_lock_bh in xfrm_policy_kill.

Fixes: ea2dea9dacc2 ("xfrm: remove policy lock when accessing policy->walk.dead")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Timo Teräs <timo.teras@iki.fi>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:24:29 +02:00
Xin Long
f5a3d5c320 xfrm: add the missing verify_sec_ctx_len check in xfrm_add_acquire
commit a1a7e3a36e01ca6e67014f8cf673cb8e47be5550 upstream.

Without doing verify_sec_ctx_len() check in xfrm_add_acquire(), it may be
out-of-bounds to access uctx->ctx_str with uctx->ctx_len, as noticed by
syz:

  BUG: KASAN: slab-out-of-bounds in selinux_xfrm_alloc_user+0x237/0x430
  Read of size 768 at addr ffff8880123be9b4 by task syz-executor.1/11650

  Call Trace:
   dump_stack+0xe8/0x16e
   print_address_description.cold.3+0x9/0x23b
   kasan_report.cold.4+0x64/0x95
   memcpy+0x1f/0x50
   selinux_xfrm_alloc_user+0x237/0x430
   security_xfrm_policy_alloc+0x5c/0xb0
   xfrm_policy_construct+0x2b1/0x650
   xfrm_add_acquire+0x21d/0xa10
   xfrm_user_rcv_msg+0x431/0x6f0
   netlink_rcv_skb+0x15a/0x410
   xfrm_netlink_rcv+0x6d/0x90
   netlink_unicast+0x50e/0x6a0
   netlink_sendmsg+0x8ae/0xd40
   sock_sendmsg+0x133/0x170
   ___sys_sendmsg+0x834/0x9a0
   __sys_sendmsg+0x100/0x1e0
   do_syscall_64+0xe5/0x660
   entry_SYSCALL_64_after_hwframe+0x6a/0xdf

So fix it by adding the missing verify_sec_ctx_len check there.

Fixes: 980ebd25794f ("[IPSEC]: Sync series - acquire insert")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:24:27 +02:00
Xin Long
8aea1c534e xfrm: fix uctx len check in verify_sec_ctx_len
commit 171d449a028573b2f0acdc7f31ecbb045391b320 upstream.

It's not sufficient to do 'uctx->len != (sizeof(struct xfrm_user_sec_ctx) +
uctx->ctx_len)' check only, as uctx->len may be greater than nla_len(rt),
in which case it will cause slab-out-of-bounds when accessing uctx->ctx_str
later.

This patch is to fix it by return -EINVAL when uctx->len > nla_len(rt).

Fixes: df71837d5024 ("[LSM-IPSec]: Security association restriction.")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:24:25 +02:00
Nicolas Dichtel
4b359d77b7 vti[6]: fix packet tx through bpf_redirect() in XinY cases
commit f1ed10264ed6b66b9cd5e8461cffce69be482356 upstream.

I forgot the 4in6/6in4 cases in my previous patch. Let's fix them.

Fixes: 95224166a903 ("vti[6]: fix packet tx through bpf_redirect()")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:24:23 +02:00
Johannes Berg
e23fad62e0 mac80211: mark station unauthorized before key removal
commit b16798f5b907733966fd1a558fca823b3c67e4a1 upstream.

If a station is still marked as authorized, mark it as no longer
so before removing its keys. This allows frames transmitted to it
to be rejected, providing additional protection against leaking
plain text data during the disconnection flow.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200326155133.ccb4fb0bb356.If48f0f0504efdcf16b8921f48c6d3bb2cb763c99@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:24:18 +02:00
Nicolas Cavallari
6e588a5806 mac80211: Do not send mesh HWMP PREQ if HWMP is disabled
[ Upstream commit ba32679cac50c38fdf488296f96b1f3175532b8e ]

When trying to transmit to an unknown destination, the mesh code would
unconditionally transmit a HWMP PREQ even if HWMP is not the current
path selection algorithm.

Signed-off-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>
Link: https://lore.kernel.org/r/20200305140409.12204-1-cavallar@lri.fr
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-07 14:24:03 +02:00
Sabrina Dubroca
8891c536ce net: ipv4: don't let PMTU updates increase route MTU
[ Upstream commit 28d35bcdd3925e7293408cdb8aa5f2aac5f0d6e3 ]

When an MTU update with PMTU smaller than net.ipv4.route.min_pmtu is
received, we must clamp its value. However, we can receive a PMTU
exception with PMTU < old_mtu < ip_rt_min_pmtu, which would lead to an
increase in PMTU.

To fix this, take the smallest of the old MTU and ip_rt_min_pmtu.

Before this patch, in case of an update, the exception's MTU would
always change. Now, an exception can have only its lock flag updated,
but not the MTU, so we need to add a check on locking to the following
"is this exception getting updated, or close to expiring?" test.

Fixes: d52e5a7e7ca4 ("ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmtu")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-07 14:23:55 +02:00
Taehee Yoo
b7c6627960 hsr: set .netnsok flag
[ Upstream commit 09e91dbea0aa32be02d8877bd50490813de56b9a ]

The hsr module has been supporting the list and status command.
(HSR_C_GET_NODE_LIST and HSR_C_GET_NODE_STATUS)
These commands send node information to the user-space via generic netlink.
But, in the non-init_net namespace, these commands are not allowed
because .netnsok flag is false.
So, there is no way to get node information in the non-init_net namespace.

Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:23:42 +02:00
Taehee Yoo
6770f4208f hsr: add restart routine into hsr_get_node_list()
[ Upstream commit ca19c70f5225771c05bcdcb832b4eb84d7271c5e ]

The hsr_get_node_list() is to send node addresses to the userspace.
If there are so many nodes, it could fail because of buffer size.
In order to avoid this failure, the restart routine is added.

Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:23:40 +02:00
Taehee Yoo
76479d6758 hsr: use rcu_read_lock() in hsr_get_node_{list/status}()
[ Upstream commit 173756b86803655d70af7732079b3aa935e6ab68 ]

hsr_get_node_{list/status}() are not under rtnl_lock() because
they are callback functions of generic netlink.
But they use __dev_get_by_index() without rtnl_lock().
So, it would use unsafe data.
In order to fix it, rcu_read_lock() and dev_get_by_index_rcu()
are used instead of __dev_get_by_index().

Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:23:38 +02:00
Cong Wang
6eb7abd02e net_sched: keep alloc_hash updated after hash allocation
[ Upstream commit 0d1c3530e1bd38382edef72591b78e877e0edcd3 ]

In commit 599be01ee567 ("net_sched: fix an OOB access in cls_tcindex")
I moved cp->hash calculation before the first
tcindex_alloc_perfect_hash(), but cp->alloc_hash is left untouched.
This difference could lead to another out of bound access.

cp->alloc_hash should always be the size allocated, we should
update it after this tcindex_alloc_perfect_hash().

Reported-and-tested-by: syzbot+dcc34d54d68ef7d2d53d@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+c72da7b9ed57cde6fca2@syzkaller.appspotmail.com
Fixes: 599be01ee567 ("net_sched: fix an OOB access in cls_tcindex")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:23:30 +02:00
Cong Wang
fe6f33384b net_sched: cls_route: remove the right filter from hashtable
[ Upstream commit ef299cc3fa1a9e1288665a9fdc8bff55629fd359 ]

route4_change() allocates a new filter and copies values from
the old one. After the new filter is inserted into the hash
table, the old filter should be removed and freed, as the final
step of the update.

However, the current code mistakenly removes the new one. This
looks apparently wrong to me, and it causes double "free" and
use-after-free too, as reported by syzbot.

Reported-and-tested-by: syzbot+f9b32aaacd60305d9687@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+2f8c233f131943d6056d@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+9c2df9fd5e9445b74e01@syzkaller.appspotmail.com
Fixes: 1109c00547fc ("net: sched: RCU cls_route")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:23:28 +02:00
Florian Fainelli
151611f656 net: dsa: Fix duplicate frames flooded by learning
[ Upstream commit 0e62f543bed03a64495bd2651d4fe1aa4bcb7fe5 ]

When both the switch and the bridge are learning about new addresses,
switch ports attached to the bridge would see duplicate ARP frames
because both entities would attempt to send them.

Fixes: 5037d532b83d ("net: dsa: add Broadcom tag RX/TX handler")
Reported-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:23:26 +02:00
Taehee Yoo
bc33b701bb hsr: fix general protection fault in hsr_addr_is_self()
[ Upstream commit 3a303cfdd28d5f930a307c82e8a9d996394d5ebd ]

The port->hsr is used in the hsr_handle_frame(), which is a
callback of rx_handler.
hsr master and slaves are initialized in hsr_add_port().
This function initializes several pointers, which includes port->hsr after
registering rx_handler.
So, in the rx_handler routine, un-initialized pointer would be used.
In order to fix this, pointers should be initialized before
registering rx_handler.

Test commands:
    ip netns del left
    ip netns del right
    modprobe -rv veth
    modprobe -rv hsr
    killall ping
    modprobe hsr
    ip netns add left
    ip netns add right
    ip link add veth0 type veth peer name veth1
    ip link add veth2 type veth peer name veth3
    ip link add veth4 type veth peer name veth5
    ip link set veth1 netns left
    ip link set veth3 netns right
    ip link set veth4 netns left
    ip link set veth5 netns right
    ip link set veth0 up
    ip link set veth2 up
    ip link set veth0 address fc:00:00:00:00:01
    ip link set veth2 address fc:00:00:00:00:02
    ip netns exec left ip link set veth1 up
    ip netns exec left ip link set veth4 up
    ip netns exec right ip link set veth3 up
    ip netns exec right ip link set veth5 up
    ip link add hsr0 type hsr slave1 veth0 slave2 veth2
    ip a a 192.168.100.1/24 dev hsr0
    ip link set hsr0 up
    ip netns exec left ip link add hsr1 type hsr slave1 veth1 slave2 veth4
    ip netns exec left ip a a 192.168.100.2/24 dev hsr1
    ip netns exec left ip link set hsr1 up
    ip netns exec left ip n a 192.168.100.1 dev hsr1 lladdr \
	    fc:00:00:00:00:01 nud permanent
    ip netns exec left ip n r 192.168.100.1 dev hsr1 lladdr \
	    fc:00:00:00:00:01 nud permanent
    for i in {1..100}
    do
        ip netns exec left ping 192.168.100.1 &
    done
    ip netns exec left hping3 192.168.100.1 -2 --flood &
    ip netns exec right ip link add hsr2 type hsr slave1 veth3 slave2 veth5
    ip netns exec right ip a a 192.168.100.3/24 dev hsr2
    ip netns exec right ip link set hsr2 up
    ip netns exec right ip n a 192.168.100.1 dev hsr2 lladdr \
	    fc:00:00:00:00:02 nud permanent
    ip netns exec right ip n r 192.168.100.1 dev hsr2 lladdr \
	    fc:00:00:00:00:02 nud permanent
    for i in {1..100}
    do
        ip netns exec right ping 192.168.100.1 &
    done
    ip netns exec right hping3 192.168.100.1 -2 --flood &
    while :
    do
        ip link add hsr0 type hsr slave1 veth0 slave2 veth2
	ip a a 192.168.100.1/24 dev hsr0
	ip link set hsr0 up
	ip link del hsr0
    done

Splat looks like:
[  120.954938][    C0] general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1]I
[  120.957761][    C0] KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
[  120.959064][    C0] CPU: 0 PID: 1511 Comm: hping3 Not tainted 5.6.0-rc5+ #460
[  120.960054][    C0] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  120.962261][    C0] RIP: 0010:hsr_addr_is_self+0x65/0x2a0 [hsr]
[  120.963149][    C0] Code: 44 24 18 70 73 2f c0 48 c1 eb 03 48 8d 04 13 c7 00 f1 f1 f1 f1 c7 40 04 00 f2 f2 f2 4
[  120.966277][    C0] RSP: 0018:ffff8880d9c09af0 EFLAGS: 00010206
[  120.967293][    C0] RAX: 0000000000000006 RBX: 1ffff1101b38135f RCX: 0000000000000000
[  120.968516][    C0] RDX: dffffc0000000000 RSI: ffff8880d17cb208 RDI: 0000000000000000
[  120.969718][    C0] RBP: 0000000000000030 R08: ffffed101b3c0e3c R09: 0000000000000001
[  120.972203][    C0] R10: 0000000000000001 R11: ffffed101b3c0e3b R12: 0000000000000000
[  120.973379][    C0] R13: ffff8880aaf80100 R14: ffff8880aaf800f2 R15: ffff8880aaf80040
[  120.974410][    C0] FS:  00007f58e693f740(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000
[  120.979794][    C0] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  120.980773][    C0] CR2: 00007ffcb8b38f29 CR3: 00000000afe8e001 CR4: 00000000000606f0
[  120.981945][    C0] Call Trace:
[  120.982411][    C0]  <IRQ>
[  120.982848][    C0]  ? hsr_add_node+0x8c0/0x8c0 [hsr]
[  120.983522][    C0]  ? rcu_read_lock_held+0x90/0xa0
[  120.984159][    C0]  ? rcu_read_lock_sched_held+0xc0/0xc0
[  120.984944][    C0]  hsr_handle_frame+0x1db/0x4e0 [hsr]
[  120.985597][    C0]  ? hsr_nl_nodedown+0x2b0/0x2b0 [hsr]
[  120.986289][    C0]  __netif_receive_skb_core+0x6bf/0x3170
[  120.992513][    C0]  ? check_chain_key+0x236/0x5d0
[  120.993223][    C0]  ? do_xdp_generic+0x1460/0x1460
[  120.993875][    C0]  ? register_lock_class+0x14d0/0x14d0
[  120.994609][    C0]  ? __netif_receive_skb_one_core+0x8d/0x160
[  120.995377][    C0]  __netif_receive_skb_one_core+0x8d/0x160
[  120.996204][    C0]  ? __netif_receive_skb_core+0x3170/0x3170
[ ... ]

Reported-by: syzbot+fcf5dd39282ceb27108d@syzkaller.appspotmail.com
Fixes: c5a759117210 ("net/hsr: Use list_head (and rcu) instead of array for slave devices.")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:23:24 +02:00
Matteo Croce
0448bfd440 ipv4: ensure rcu_read_lock() in cipso_v4_error()
commit 3e72dfdf8227b052393f71d820ec7599909dddc2 upstream.

Similarly to commit c543cb4a5f07 ("ipv4: ensure rcu_read_lock() in
ipv4_link_failure()"), __ip_options_compile() must be called under rcu
protection.

Fixes: 3da1ed7ac398 ("net: avoid use IPCB in cipso_v4_error")
Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:45 +02:00
Sven Eckelmann
de5c446d49 batman-adv: Don't schedule OGM for disabled interface
A transmission scheduling for an interface which is currently dropped by
batadv_iv_ogm_iface_disable could still be in progress. The B.A.T.M.A.N. V
is simply cancelling the workqueue item in an synchronous way but this is
not possible with B.A.T.M.A.N. IV because the OGM submissions are
intertwined.

Instead it has to stop submitting the OGM when it detect that the buffer
pointer is set to NULL.

Reported-by: syzbot+a98f2016f40b9cd3818a@syzkaller.appspotmail.com
Reported-by: syzbot+ac36b6a33c28a491e929@syzkaller.appspotmail.com
Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Cc: Hillf Danton <hdanton@sina.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:30 +02:00
Sven Eckelmann
d5a4774ceb batman-adv: Avoid free/alloc race when handling OGM buffer
commit 40e220b4218bb3d278e5e8cc04ccdfd1c7ff8307 upstream.

Each slave interface of an B.A.T.M.A.N. IV virtual interface has an OGM
packet buffer which is initialized using data from netdevice notifier and
other rtnetlink related hooks. It is sent regularly via various slave
interfaces of the batadv virtual interface and in this process also
modified (realloced) to integrate additional state information via TVLV
containers.

It must be avoided that the worker item is executed without a common lock
with the netdevice notifier/rtnetlink helpers. Otherwise it can either
happen that half modified/freed data is sent out or functions modifying the
OGM buffer try to access already freed memory regions.

Reported-by: syzbot+0cc629f19ccb8534935b@syzkaller.appspotmail.com
Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:28 +02:00
Sven Eckelmann
9a4cdddfbc batman-adv: Only read OGM tvlv_len after buffer len check
commit a15d56a60760aa9dbe26343b9a0ac5228f35d445 upstream.

Multiple batadv_ogm_packet can be stored in an skbuff. The functions
batadv_iv_ogm_send_to_if()/batadv_iv_ogm_receive() use
batadv_iv_ogm_aggr_packet() to check if there is another additional
batadv_ogm_packet in the skb or not before they continue processing the
packet.

The length for such an OGM is BATADV_OGM_HLEN +
batadv_ogm_packet->tvlv_len. The check must first check that at least
BATADV_OGM_HLEN bytes are available before it accesses tvlv_len (which is
part of the header. Otherwise it might try read outside of the currently
available skbuff to get the content of tvlv_len.

Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure")
Reported-by: syzbot+355cab184197dbbfa384@syzkaller.appspotmail.com
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:26 +02:00
Sven Eckelmann
3c3b7dd776 batman-adv: Reduce tt_global hash refcnt only for removed entry
commit f131a56880d10932931e74773fb8702894a94a75 upstream.

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: 7683fdc1e886 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:24 +02:00
Sven Eckelmann
0496dec5ab batman-adv: Reduce tt_local hash refcnt only for removed entry
commit 3d65b9accab4a7ed5038f6df403fbd5e298398c7 upstream.

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: ef72706a0543 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:23 +02:00
Sven Eckelmann
2b1972a937 batman-adv: Reduce claim hash refcnt only for removed entry
commit 4ba104f468bbfc27362c393815d03aa18fb7a20f upstream.

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_bla_del_claim 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: 23721387c409 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:21 +02:00
Sven Eckelmann
75c6628551 batman-adv: Prevent duplicated tvlv handler
commit ae3cdc97dc10c7a3b31f297dab429bfb774c9ccb upstream.

The function batadv_tvlv_handler_register is responsible for adding new
tvlv_handler to the handler_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: ef26157747d4 ("batman-adv: tvlv - basic infrastructure")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:19 +02:00
Sven Eckelmann
a1d3431327 batman-adv: Prevent duplicated global TT entry
commit e7136e48ffdfb9f37b0820f619380485eb407361 upstream.

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: d657e621a0f5 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:17 +02:00
Sven Eckelmann
56562e5200 batman-adv: Prevent duplicated nc_node entry
commit fa122fec8640eb7186ce5a41b83a4c1744ceef8f upstream.

The function batadv_nc_get_nc_node is responsible for adding new nc_nodes
to the in_coding_list and out_coding_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: d56b1705e28c ("batman-adv: network coding - detect coding nodes and remove these after timeout")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:15 +02:00
Sven Eckelmann
10cec2f4ea batman-adv: Prevent duplicated gateway_node entry
commit dff9bc42ab0b2d38c5e90ddd79b238fed5b4c7ad upstream.

The function batadv_gw_node_add is responsible for adding new gw_node to
the gateway_list. It is expecting that the caller already checked that
there is not already an entry with the same key or not.

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: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:14 +02:00
Linus Lüssing
2546018a8e batman-adv: Avoid storing non-TT-sync flags on singular entries too
commit 4a519b83da16927fb98fd32b0f598e639d1f1859 upstream.

Since commit 54e22f265e87 ("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: 54e22f265e87 ("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>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:12 +02:00
Sven Eckelmann
bb227afa99 batman-adv: Fix debugfs path for renamed softif
commit 6da7be7d24b2921f8215473ba7552796dff05fe1 upstream.

batman-adv is creating special debugfs directories in the init
net_namespace for each created soft-interface (batadv net_device). But it
is possible to rename a net_device to a completely different name then the
original one.

It can therefore happen that a user registers a new batadv net_device with
the name "bat0". batman-adv is then also adding a new directory under
$debugfs/batman-adv/ with the name "wlan0".

The user then decides to rename this device to "bat1" and registers a
different batadv device with the name "bat0". batman-adv will then try to
create a directory with the name "bat0" under $debugfs/batman-adv/ again.
But there already exists one with this name under this path and thus this
fails. batman-adv will detect a problem and rollback the registering of
this device.

batman-adv must therefore take care of renaming the debugfs directories for
soft-interfaces whenever it detects such a net_device rename.

Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:10 +02:00
Sven Eckelmann
3b9d60c648 batman-adv: Fix debugfs path for renamed hardif
commit 36dc621ceca1be3ec885aeade5fdafbbcc452a6d upstream.

batman-adv is creating special debugfs directories in the init
net_namespace for each valid hard-interface (net_device). But it is
possible to rename a net_device to a completely different name then the
original one.

It can therefore happen that a user registers a new net_device which gets
the name "wlan0" assigned by default. batman-adv is also adding a new
directory under $debugfs/batman-adv/ with the name "wlan0".

The user then decides to rename this device to "wl_pri" and registers a
different device. The kernel may now decide to use the name "wlan0" again
for this new device. batman-adv will detect it as a valid net_device and
tries to create a directory with the name "wlan0" under
$debugfs/batman-adv/. But there already exists one with this name under
this path and thus this fails. batman-adv will detect a problem and
rollback the registering of this device.

batman-adv must therefore take care of renaming the debugfs directories
for hard-interfaces whenever it detects such a net_device rename.

Fixes: 5bc7c1eb44f2 ("batman-adv: add debugfs structure for information per interface")
Reported-by: John Soros <sorosj@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:08 +02:00
Marek Lindner
93a64d408c batman-adv: prevent TT request storms by not sending inconsistent TT TLVLs
commit 16116dac23396e73c01eeee97b102e4833a4b205 upstream.

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>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:06 +02:00
Linus Lüssing
334b5a05e7 batman-adv: Fix TT sync flags for intermediate TT responses
commit 7072337e52b3e9d5460500d8dc9cbc1ba2db084c upstream.

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: e9c00136a475 ("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>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:04 +02:00
Sven Eckelmann
423539f68d batman-adv: Avoid race in TT TVLV allocator helper
commit 8ba0f9bd3bdea1058c2b2676bec7905724418e40 upstream.

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: 7ea7b4a14275 ("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>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:02 +02:00
Sven Eckelmann
cb488da495 batman-adv: Fix skbuff rcsum on packet reroute
commit fc04fdb2c8a894283259f5621d31d75610701091 upstream.

batadv_check_unicast_ttvn may redirect a packet to itself or another
originator. This involves rewriting the ttvn and the destination address in
the batadv unicast header. These field were not yet pulled (with skb rcsum
update) and thus any change to them also requires a change in the receive
checksum.

Reported-by: Matthias Schiffer <mschiffer@universe-factory.net>
Fixes: a73105b8d4c7 ("batman-adv: improved client announcement mechanism")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:13:00 +02:00
Matthias Schiffer
b04190583e batman-adv: update data pointers after skb_cow()
commit bc44b78157f621ff2a2618fe287a827bcb094ac4 upstream.

batadv_check_unicast_ttvn() calls skb_cow(), so pointers into the SKB data
must be (re)set after calling it. The ethhdr variable is dropped
altogether.

Fixes: 78fc6bbe0aca ("batman-adv: add UNICAST_4ADDR packet type")
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:58 +02:00
Sven Eckelmann
0d0eed9de8 batman-adv: Fix internal interface indices types
commit f22e08932c2960f29b5e828e745c9f3fb7c1bb86 upstream.

batman-adv uses internal indices for each enabled and active interface.
It is currently used by the B.A.T.M.A.N. IV algorithm to identifify the
correct position in the ogm_cnt bitmaps.

The type for the number of enabled interfaces (which defines the next
interface index) was set to char. This type can be (depending on the
architecture) either signed (limiting batman-adv to 127 active slave
interfaces) or unsigned (limiting batman-adv to 255 active slave
interfaces).

This limit was not correctly checked when an interface was enabled and thus
an overflow happened. This was only catched on systems with the signed char
type when the B.A.T.M.A.N. IV code tried to resize its counter arrays with
a negative size.

The if_num interface index was only a s16 and therefore significantly
smaller than the ifindex (int) used by the code net code.

Both &batadv_hard_iface->if_num and &batadv_priv->num_ifaces must be
(unsigned) int to support the same number of slave interfaces as the net
core code. And the interface activation code must check the number of
active slave interfaces to avoid integer overflows.

Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:56 +02:00
Sven Eckelmann
d5b8133215 batman-adv: Fix lock for ogm cnt access in batadv_iv_ogm_calc_tq
commit 5ba7dcfe77037b67016263ea597a8b431692ecab upstream.

The originator node object orig_neigh_node is used to when accessing the
bcast_own(_sum) and real_packet_count information. The access to them has
to be protected with the spinlock in orig_neigh_node.

But the function uses the lock in orig_node instead. This is incorrect
because they could be two different originator node objects.

Fixes: 0ede9f41b217 ("batman-adv: protect bit operations to count OGMs with spinlock")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:55 +02:00
Linus Lüssing
6b1cdb86c6 batman-adv: fix TT sync flag inconsistencies
commit 54e22f265e872ae140755b3318521d400a094605 upstream.

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: e9c00136a475 ("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>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:53 +02:00
Sven Eckelmann
e556ed1124 batman-adv: Fix rx packet/bytes stats on local ARP reply
commit 36d4d68cd658d914ef73ac845705c4a89e7d9e2f upstream.

The stats are generated by batadv_interface_stats and must not be stored
directly in the net_device stats member variable. The batadv_priv
bat_counters information is assembled when ndo_get_stats is called. The
stats previously stored in net_device::stats is then overwritten.

The batman-adv counters must therefore be increased when an ARP packet is
answered locally via the distributed arp table.

Fixes: c384ea3ec930 ("batman-adv: Distributed ARP Table - add snooping functions for ARP messages")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:51 +02:00
Linus Lüssing
963d766ddd batman-adv: Fix transmission of final, 16th fragment
commit 51c6b429c0c95e67edd1cb0b548c5cf6a6604763 upstream.

Trying to split and transmit a unicast packet in 16 parts will fail for
the final fragment: After having sent the 15th one with a frag_packet.no
index of 14, we will increase the the index to 15 - and return with an
error code immediately, even though one more fragment is due for
transmission and allowed.

Fixing this issue by moving the check before incrementing the index.

While at it, adding an unlikely(), because the check is actually more of
an assertion.

Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu")
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>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:49 +02:00
Sven Eckelmann
3542876660 batman-adv: Fix double free during fragment merge error
commit 248e23b50e2da0753f3b5faa068939cbe9f8a75a upstream.

The function batadv_frag_skb_buffer was supposed not to consume the skbuff
on errors. This was followed in the helper function
batadv_frag_insert_packet when the skb would potentially be inserted in the
fragment queue. But it could happen that the next helper function
batadv_frag_merge_packets would try to merge the fragments and fail. This
results in a kfree_skb of all the enqueued fragments (including the just
inserted one). batadv_recv_frag_packet would detect the error in
batadv_frag_skb_buffer and try to free the skb again.

The behavior of batadv_frag_skb_buffer (and its helper
batadv_frag_insert_packet) must therefore be changed to always consume the
skbuff to have a common behavior and avoid the double kfree_skb.

Fixes: 610bfc6bc99b ("batman-adv: Receive fragmented packets and merge")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:47 +02:00
Sven Eckelmann
5e6cd50447 batman-adv: Add missing refcnt for last_candidate
commit 936523441bb64cdc9a5b263e8fd2782e70313a57 upstream.

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: f3b3d9018975 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:45 +02:00
Sven Eckelmann
77a9fa00c7 batman-adv: Fix speedy join in gateway client mode
commit d1fe176ca51fa3cb35f70c1d876d9a090e9befce upstream.

Speedy join only works when the received packet is either broadcast or an
4addr unicast packet. Thus packets converted from broadcast to unicast via
the gateway handling code have to be converted to 4addr packets to allow
the receiving gateway server to add the sender address as temporary entry
to the translation table.

Not doing it will make the batman-adv gateway server drop the DHCP response
in many situations because it doesn't yet have the TT entry for the
destination of the DHCP response.

Fixes: 371351731e9c ("batman-adv: change interface_rx to get orig node")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:44 +02:00
Sven Eckelmann
69e355c51d batman-adv: Free last_bonding_candidate on release of orig_node
commit cbef1e102003edb236c6b2319ab269ccef963731 upstream.

The orig_ifinfo reference counter for last_bonding_candidate in
batadv_orig_node has to be reduced when an originator node is released.
Otherwise the orig_ifinfo is leaked and the reference counter the netdevice
is not reduced correctly.

Fixes: f3b3d9018975 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:42 +02:00
Sven Eckelmann
c295544443 batman-adv: Fix reference leak in batadv_find_router
commit 15c2ed753cd9e3e746472deab8151337a5b6da56 upstream.

The replacement of last_bonding_candidate in batadv_orig_node has to be an
atomic operation. Otherwise it is possible that the reference counter of a
batadv_orig_ifinfo is reduced which was no longer the
last_bonding_candidate when the new candidate is added. This can either
lead to an invalid memory access or to reference leaks which make it
impossible to an interface which was added to batman-adv.

Fixes: f3b3d9018975 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:40 +02:00
Sven Eckelmann
155d047c62 batman-adv: Fix non-atomic bla_claim::backbone_gw access
commit 3db0decf1185357d6ab2256d0dede1ca9efda03d upstream.

The pointer batadv_bla_claim::backbone_gw can be changed at any time.
Therefore, access to it must be protected to ensure that two function
accessing the same backbone_gw are actually accessing the same. This is
especially important when the crc_lock is used or when the backbone_gw of a
claim is exchanged.

Not doing so leads to invalid memory access and/or reference leaks.

Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code")
Fixes: 5a1dd8a4773d ("batman-adv: lock crc access in bridge loop avoidance")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:38 +02:00
Simon Wunderlich
b5b6bd908f batman-adv: lock crc access in bridge loop avoidance
commit 5a1dd8a4773d4c24e925cc6154826d555a85c370 upstream.

We have found some networks in which nodes were constantly requesting
other nodes BLA claim tables to synchronize, just to ask for that again
once completed. The reason was that the crc checksum of the asked nodes
were out of sync due to missing locking and multiple writes to the same
crc checksum when adding/removing entries. Therefore the asked nodes
constantly reported the wrong crc, which caused repeating requests.

To avoid multiple functions changing a backbone gateways crc entry at
the same time, lock it using a spinlock.

Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Tested-by: Alfons Name <AlfonsName@web.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:36 +02:00
Sven Eckelmann
dbc770a68e batman-adv: Fix orig_node_vlan leak on orig_node_release
commit 33fbb1f3db87ce53da925b3e034b4dd446d483f8 upstream.

batadv_orig_node_new uses batadv_orig_node_vlan_new to allocate a new
batadv_orig_node_vlan and add it to batadv_orig_node::vlan_list. References
to this list have also to be cleaned when the batadv_orig_node is removed.

Fixes: 7ea7b4a14275 ("batman-adv: make the TT CRC logic VLAN specific")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:34 +02:00
Sven Eckelmann
8ccd4a2388 batman-adv: Avoid nullptr dereference in dat after vlan_insert_tag
commit 60154a1e0495ffb8343a95cefe1e874634572fa8 upstream.

vlan_insert_tag can return NULL on errors. The distributed arp table code
therefore has to check the return value of vlan_insert_tag for NULL before
it can safely operate on this pointer.

Fixes: be1db4f6615b ("batman-adv: make the Distributed ARP Table vlan aware")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:33 +02:00
Sven Eckelmann
513d406f1c batman-adv: Avoid nullptr dereference in bla after vlan_insert_tag
commit 10c78f5854d361ded4736c1831948e0a5f67b932 upstream.

vlan_insert_tag can return NULL on errors. The bridge loop avoidance code
therefore has to check the return value of vlan_insert_tag for NULL before
it can safely operate on this pointer.

Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:31 +02:00
Sven Eckelmann
cc2c95507b batman-adv: Clean up untagged vlan when destroying via rtnl-link
commit 420cb1b764f9169c5d2601b4af90e4a1702345ee upstream.

The untagged vlan object is only destroyed when the interface is removed
via the legacy sysfs interface. But it also has to be destroyed when the
standard rtnl-link interface is used.

Fixes: 5d2c05b21337 ("batman-adv: add per VLAN interface attribute framework")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:12:29 +02:00