Commit graph

1373 commits

Author SHA1 Message Date
Remi Pommarel
64453d60e6 batman-adv: Fix batadv_v_ogm_aggr_send memory leak
commit 421d467dc2d483175bad4fb76a31b9e5a3d744cf upstream.

When batadv_v_ogm_aggr_send is called for an inactive interface, the skb
is silently dropped by batadv_v_ogm_send_to_if() but never freed causing
the following memory leak:

  unreferenced object 0xffff00000c164800 (size 512):
    comm "kworker/u8:1", pid 2648, jiffies 4295122303 (age 97.656s)
    hex dump (first 32 bytes):
      00 80 af 09 00 00 ff ff e1 09 00 00 75 01 60 83  ............u.`.
      1f 00 00 00 b8 00 00 00 15 00 05 00 da e3 d3 64  ...............d
    backtrace:
      [<0000000007ad20f6>] __kmalloc_track_caller+0x1a8/0x310
      [<00000000d1029e55>] kmalloc_reserve.constprop.0+0x70/0x13c
      [<000000008b9d4183>] __alloc_skb+0xec/0x1fc
      [<00000000c7af5051>] __netdev_alloc_skb+0x48/0x23c
      [<00000000642ee5f5>] batadv_v_ogm_aggr_send+0x50/0x36c
      [<0000000088660bd7>] batadv_v_ogm_aggr_work+0x24/0x40
      [<0000000042fc2606>] process_one_work+0x3b0/0x610
      [<000000002f2a0b1c>] worker_thread+0xa0/0x690
      [<0000000059fae5d4>] kthread+0x1fc/0x210
      [<000000000c587d3a>] ret_from_fork+0x10/0x20

Free the skb in that case to fix this leak.

Cc: stable@vger.kernel.org
Fixes: 0da0035942 ("batman-adv: OGMv2 - add basic infrastructure")
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
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>
2023-08-30 16:31:55 +02:00
Remi Pommarel
6c1ebf799f batman-adv: Fix TT global entry leak when client roamed back
commit d25ddb7e788d34cf27ff1738d11a87cb4b67d446 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-30 16:31:55 +02:00
Remi Pommarel
fa8fa81cb8 batman-adv: Do not get eth header before batadv_check_management_packet
commit eac27a41ab641de074655d2932fc7f8cdb446881 upstream.

If received skb in batadv_v_elp_packet_recv or batadv_v_ogm_packet_recv
is either cloned or non linearized then its data buffer will be
reallocated by batadv_check_management_packet when skb_cow or
skb_linearize get called. Thus geting ethernet header address inside
skb data buffer before batadv_check_management_packet had any chance to
reallocate it could lead to the following kernel panic:

  Unable to handle kernel paging request at virtual address ffffff8020ab069a
  Mem abort info:
    ESR = 0x96000007
    EC = 0x25: DABT (current EL), IL = 32 bits
    SET = 0, FnV = 0
    EA = 0, S1PTW = 0
    FSC = 0x07: level 3 translation fault
  Data abort info:
    ISV = 0, ISS = 0x00000007
    CM = 0, WnR = 0
  swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000040f45000
  [ffffff8020ab069a] pgd=180000007fffa003, p4d=180000007fffa003, pud=180000007fffa003, pmd=180000007fefe003, pte=0068000020ab0706
  Internal error: Oops: 96000007 [#1] SMP
  Modules linked in: ahci_mvebu libahci_platform libahci dvb_usb_af9035 dvb_usb_dib0700 dib0070 dib7000m dibx000_common ath11k_pci ath10k_pci ath10k_core mwl8k_new nf_nat_sip nf_conntrack_sip xhci_plat_hcd xhci_hcd nf_nat_pptp nf_conntrack_pptp at24 sbsa_gwdt
  CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.15.42-00066-g3242268d425c-dirty #550
  Hardware name: A8k (DT)
  pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
  pc : batadv_is_my_mac+0x60/0xc0
  lr : batadv_v_ogm_packet_recv+0x98/0x5d0
  sp : ffffff8000183820
  x29: ffffff8000183820 x28: 0000000000000001 x27: ffffff8014f9af00
  x26: 0000000000000000 x25: 0000000000000543 x24: 0000000000000003
  x23: ffffff8020ab0580 x22: 0000000000000110 x21: ffffff80168ae880
  x20: 0000000000000000 x19: ffffff800b561000 x18: 0000000000000000
  x17: 0000000000000000 x16: 0000000000000000 x15: 00dc098924ae0032
  x14: 0f0405433e0054b0 x13: ffffffff00000080 x12: 0000004000000001
  x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
  x8 : 0000000000000000 x7 : ffffffc076dae000 x6 : ffffff8000183700
  x5 : ffffffc00955e698 x4 : ffffff80168ae000 x3 : ffffff80059cf000
  x2 : ffffff800b561000 x1 : ffffff8020ab0696 x0 : ffffff80168ae880
  Call trace:
   batadv_is_my_mac+0x60/0xc0
   batadv_v_ogm_packet_recv+0x98/0x5d0
   batadv_batman_skb_recv+0x1b8/0x244
   __netif_receive_skb_core.isra.0+0x440/0xc74
   __netif_receive_skb_one_core+0x14/0x20
   netif_receive_skb+0x68/0x140
   br_pass_frame_up+0x70/0x80
   br_handle_frame_finish+0x108/0x284
   br_handle_frame+0x190/0x250
   __netif_receive_skb_core.isra.0+0x240/0xc74
   __netif_receive_skb_list_core+0x6c/0x90
   netif_receive_skb_list_internal+0x1f4/0x310
   napi_complete_done+0x64/0x1d0
   gro_cell_poll+0x7c/0xa0
   __napi_poll+0x34/0x174
   net_rx_action+0xf8/0x2a0
   _stext+0x12c/0x2ac
   run_ksoftirqd+0x4c/0x7c
   smpboot_thread_fn+0x120/0x210
   kthread+0x140/0x150
   ret_from_fork+0x10/0x20
  Code: f9403844 eb03009f 54fffee1 f94

Thus ethernet header address should only be fetched after
batadv_check_management_packet has been called.

Fixes: 0da0035942 ("batman-adv: OGMv2 - add basic infrastructure")
Cc: stable@vger.kernel.org
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
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>
2023-08-30 16:31:55 +02:00
Sven Eckelmann
90cf70a647 batman-adv: Don't increase MTU when set by user
commit d8e42a2b0addf238be8b3b37dcd9795a5c1be459 upstream.

If the user set an MTU value, it usually means that there are special
requirements for the MTU. But if an interface gots activated, the MTU was
always recalculated and then the user set value was overwritten.

The only reason why this user set value has to be overwritten, is when the
MTU has to be decreased because batman-adv is not able to transfer packets
with the user specified size.

Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Cc: stable@vger.kernel.org
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>
2023-08-30 16:31:55 +02:00
Sven Eckelmann
3035b3f54f batman-adv: Trigger events for auto adjusted MTU
commit c6a953cce8d0438391e6da48c8d0793d3fbfcfa6 upstream.

If an interface changes the MTU, it is expected that an NETDEV_PRECHANGEMTU
and NETDEV_CHANGEMTU notification events is triggered. This worked fine for
.ndo_change_mtu based changes because core networking code took care of it.
But for auto-adjustments after hard-interfaces changes, these events were
simply missing.

Due to this problem, non-batman-adv components weren't aware of MTU changes
and thus couldn't perform their own tasks correctly.

Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Cc: stable@vger.kernel.org
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>
2023-08-30 16:31:54 +02:00
Vladislav Efanov
819c30857d batman-adv: Broken sync while rescheduling delayed work
commit abac3ac97fe8734b620e7322a116450d7f90aa43 upstream.

Syzkaller got a lot of crashes like:
KASAN: use-after-free Write in *_timers*

All of these crashes point to the same memory area:

The buggy address belongs to the object at ffff88801f870000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 5320 bytes inside of
 8192-byte region [ffff88801f870000, ffff88801f872000)

This area belongs to :
        batadv_priv->batadv_priv_dat->delayed_work->timer_list

The reason for these issues is the lack of synchronization. Delayed
work (batadv_dat_purge) schedules new timer/work while the device
is being deleted. As the result new timer/delayed work is set after
cancel_delayed_work_sync() was called. So after the device is freed
the timer list contains pointer to already freed memory.

Found by Linux Verification Center (linuxtesting.org) with syzkaller.

Cc: stable@kernel.org
Fixes: 2f1dfbe185 ("batman-adv: Distributed ARP Table - implement local storage")
Signed-off-by: Vladislav Efanov <VEfanov@ispras.ru>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-14 10:57:13 +02:00
Sven Eckelmann
5853618b02 batman-adv: Don't skb_split skbuffs with frag_list
[ Upstream commit a063f2fba3fa633a599253b62561051ac185fa99 ]

The receiving interface might have used GRO to receive more fragments than
MAX_SKB_FRAGS fragments. In this case, these will not be stored in
skb_shinfo(skb)->frags but merged into the frag list.

batman-adv relies on the function skb_split to split packets up into
multiple smaller packets which are not larger than the MTU on the outgoing
interface. But this function cannot handle frag_list entries and is only
operating on skb_shinfo(skb)->frags. If it is still trying to split such an
skb and xmit'ing it on an interface without support for NETIF_F_FRAGLIST,
then validate_xmit_skb() will try to linearize it. But this fails due to
inconsistent information. And __pskb_pull_tail will trigger a BUG_ON after
skb_copy_bits() returns an error.

In case of entries in frag_list, just linearize the skb before operating on
it with skb_split().

Reported-by: Felix Kaechele <felix@kaechele.ca>
Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Tested-by: Felix Kaechele <felix@kaechele.ca>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 09:42:47 +02:00
Sven Eckelmann
92a556ef51 batman-adv: Don't expect inter-netns unique iflink indices
commit 6c1f41afc1dbe59d9d3c8bb0d80b749c119aa334 upstream.

The ifindex doesn't have to be unique for multiple network namespaces on
the same machine.

  $ ip netns add test1
  $ ip -net test1 link add dummy1 type dummy
  $ ip netns add test2
  $ ip -net test2 link add dummy2 type dummy

  $ ip -net test1 link show dev dummy1
  6: dummy1: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 96:81:55:1e:dd:85 brd ff:ff:ff:ff:ff:ff
  $ ip -net test2 link show dev dummy2
  6: dummy2: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 5a:3c:af:35:07:c3 brd ff:ff:ff:ff:ff:ff

But the batman-adv code to walk through the various layers of virtual
interfaces uses this assumption because dev_get_iflink handles it
internally and doesn't return the actual netns of the iflink. And
dev_get_iflink only documents the situation where ifindex == iflink for
physical devices.

But only checking for dev->netdev_ops->ndo_get_iflink is also not an option
because ipoib_get_iflink implements it even when it sometimes returns an
iflink != ifindex and sometimes iflink == ifindex. The caller must
therefore make sure itself to check both netns and iflink + ifindex for
equality. Only when they are equal, a "physical" interface was detected
which should stop the traversal. On the other hand, vxcan_get_iflink can
also return 0 in case there was currently no valid peer. In this case, it
is still necessary to stop.

Fixes: b7eddd0b39 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface")
Fixes: 5ed4a460a1 ("batman-adv: additional checks for virtual interfaces on top of WiFi")
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
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>
2022-03-08 19:04:08 +01:00
Sven Eckelmann
130ec90cb3 batman-adv: Request iflink once in batadv_get_real_netdevice
commit 6116ba09423f7d140f0460be6a1644dceaad00da upstream.

There is no need to call dev_get_iflink multiple times for the same
net_device in batadv_get_real_netdevice. And since some of the
ndo_get_iflink callbacks are dynamic (for example via RCUs like in
vxcan_get_iflink), it could easily happen that the returned values are not
stable. The pre-checks before __dev_get_by_index are then of course bogus.

Fixes: 5ed4a460a1 ("batman-adv: additional checks for virtual interfaces on top of WiFi")
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>
2022-03-08 19:04:07 +01:00
Sven Eckelmann
86b66abce8 batman-adv: Request iflink once in batadv-on-batadv check
commit 690bb6fb64f5dc7437317153902573ecad67593d upstream.

There is no need to call dev_get_iflink multiple times for the same
net_device in batadv_is_on_batman_iface. And since some of the
.ndo_get_iflink callbacks are dynamic (for example via RCUs like in
vxcan_get_iflink), it could easily happen that the returned values are not
stable. The pre-checks before __dev_get_by_index are then of course bogus.

Fixes: b7eddd0b39 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface")
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>
2022-03-08 19:04:07 +01:00
Sven Eckelmann
d6d73a8c00 batman-adv: Don't always reallocate the fragmentation skb head
commit 992b03b88e36254e26e9a4977ab948683e21bd9f upstream.

When a packet is fragmented by batman-adv, the original batman-adv header
is not modified. Only a new fragmentation is inserted between the original
one and the ethernet header. The code must therefore make sure that it has
a writable region of this size in the skbuff head.

But it is not useful to always reallocate the skbuff by this size even when
there would be more than enough headroom still in the skb. The reallocation
is just to costly during in this codepath.

Fixes: ee75ed8887 ("batman-adv: Fragment and send skbs larger than mtu")
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>
2021-11-26 11:36:24 +01:00
Sven Eckelmann
aef9f5fca2 batman-adv: Reserve needed_*room for fragments
commit c5cbfc87558168ef4c3c27ce36eba6b83391db19 upstream.

The batadv net_device is trying to propagate the needed_headroom and
needed_tailroom from the lower devices. This is needed to avoid cost
intensive reallocations using pskb_expand_head during the transmission.

But the fragmentation code split the skb's without adding extra room at the
end/beginning of the various fragments. This reduced the performance of
transmissions over complex scenarios (batadv on vxlan on wireguard) because
the lower devices had to perform the reallocations at least once.

Fixes: ee75ed8887 ("batman-adv: Fragment and send skbs larger than mtu")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
[ bp: 4.19 backported: adjust context. ]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-26 11:36:24 +01:00
Sven Eckelmann
069e51e9a4 batman-adv: Consider fragmentation for needed_headroom
commit 4ca23e2c2074465bff55ea14221175fecdf63c5f upstream.

If a batman-adv packets has to be fragmented, then the original batman-adv
packet header is not stripped away. Instead, only a new header is added in
front of the packet after it was split.

This size must be considered to avoid cost intensive reallocations during
the transmission through the various device layers.

Fixes: 7bca68c784 ("batman-adv: Add lower layer needed_(head|tail)room to own ones")
Reported-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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-26 11:36:24 +01:00
Linus Lüssing
68d6695c50 batman-adv: mcast: fix duplicate mcast packets in BLA backbone from LAN
commit 3236d215ad38a3f5372e65cd1e0a52cf93d3c6a2 upstream.

Scenario:
* Multicast frame send from a BLA backbone (multiple nodes with
  their bat0 bridged together, with BLA enabled)

Issue:
* BLA backbone nodes receive the frame multiple times on bat0

For multicast frames received via batman-adv broadcast packets the
originator of the broadcast packet is checked before decapsulating and
forwarding the frame to bat0 (batadv_bla_is_backbone_gw()->
batadv_recv_bcast_packet()). If it came from a node which shares the
same BLA backbone with us then it is not forwarded to bat0 to avoid a
loop.

When sending a multicast frame in a non-4-address batman-adv unicast
packet we are currently missing this check - and cannot do so because
the batman-adv unicast packet has no originator address field.

However, we can simply fix this on the sender side by only sending the
multicast frame via unicasts to interested nodes which do not share the
same BLA backbone with us. This also nicely avoids some unnecessary
transmissions on mesh side.

Note that no infinite loop was observed, probably because of dropping
via batadv_interface_tx()->batadv_bla_tx(). However the duplicates still
utterly confuse switches/bridges, ICMPv6 duplicate address detection and
neighbor discovery and therefore leads to long delays before being able
to establish TCP connections, for instance. And it also leads to the Linux
bridge printing messages like:
"br-lan: received packet on eth1 with own address as source address ..."

Fixes: 1d8ab8d3c1 ("batman-adv: Modified forwarding behaviour for multicast packets")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
[ bp: 4.19 backport: drop usage in non-existing batadv_mcast_forw*, correct
  fixes line ]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-26 11:36:24 +01:00
Pavel Skripkin
fbf150b16a net: batman-adv: fix error handling
commit 6f68cd634856f8ca93bafd623ba5357e0f648c68 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-02 18:26:45 +01:00
Sven Eckelmann
e8e9d2968a batman-adv: Avoid WARN_ON timing related checks
[ Upstream commit 9f460ae31c4435fd022c443a6029352217a16ac1 ]

The soft/batadv interface for a queued OGM can be changed during the time
the OGM was queued for transmission and when the OGM is actually
transmitted by the worker.

But WARN_ON must be used to denote kernel bugs and not to print simple
warnings. A warning can simply be printed using pr_warn.

Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: syzbot+c0b807de416427ff3dd1@syzkaller.appspotmail.com
Fixes: ef0a937f7a ("batman-adv: consider outgoing interface in OGM sending")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-30 08:48:15 -04:00
Tetsuo Handa
086d27b51d batman-adv: initialize "struct batadv_tvlv_tt_vlan_data"->reserved field
commit 08c27f3322fec11950b8f1384aa0f3b11d028528 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-14 08:22:33 +02:00
Taehee Yoo
fbcca50fd5 batman-adv: set .owner to THIS_MODULE
[ Upstream commit 14a2e551faea53d45bc11629a9dac88f88950ca7 ]

If THIS_MODULE is not set, the module would be removed while debugfs is
being used.
It eventually makes kernel panic.

Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-02 08:48:10 +01:00
Linus Lüssing
41f5e62866 batman-adv: mcast: fix duplicate mcast packets from BLA backbone to mesh
[ Upstream commit 2369e827046920ef0599e6a36b975ac5c0a359c2 ]

Scenario:
* Multicast frame send from BLA backbone gateways (multiple nodes
  with their bat0 bridged together, with BLA enabled) sharing the same
  LAN to nodes in the mesh

Issue:
* Nodes receive the frame multiple times on bat0 from the mesh,
  once from each foreign BLA backbone gateway which shares the same LAN
  with another

For multicast frames via batman-adv broadcast packets coming from the
same BLA backbone but from different backbone gateways duplicates are
currently detected via a CRC history of previously received packets.

However this CRC so far was not performed for multicast frames received
via batman-adv unicast packets. Fixing this by appyling the same check
for such packets, too.

Room for improvements in the future: Ideally we would introduce the
possibility to not only claim a client, but a complete originator, too.
This would allow us to only send a multicast-in-unicast packet from a BLA
backbone gateway claiming the node and by that avoid potential redundant
transmissions in the first place.

Fixes: 279e89b2281a ("batman-adv: add broadcast duplicate check")
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: Sasha Levin <sashal@kernel.org>
2020-10-01 13:14:52 +02:00
Linus Lüssing
5ccdc27806 batman-adv: mcast: fix duplicate mcast packets in BLA backbone from mesh
[ Upstream commit 74c09b7275126da1b642b90c9cdc3ae8b729ad4b ]

Scenario:
* Multicast frame send from mesh to a BLA backbone (multiple nodes
  with their bat0 bridged together, with BLA enabled)

Issue:
* BLA backbone nodes receive the frame multiple times on bat0,
  once from mesh->bat0 and once from each backbone_gw from LAN

For unicast, a node will send only to the best backbone gateway
according to the TQ. However for multicast we currently cannot determine
if multiple destination nodes share the same backbone if they don't share
the same backbone with us. So we need to keep sending the unicasts to
all backbone gateways and let the backbone gateways decide which one
will forward the frame. We can use the CLAIM mechanism to make this
decision.

One catch: The batman-adv gateway feature for DHCP packets potentially
sends multicast packets in the same batman-adv unicast header as the
multicast optimizations code. And we are not allowed to drop those even
if we did not claim the source address of the sender, as for such
packets there is only this one multicast-in-unicast packet.

How can we distinguish the two cases?

The gateway feature uses a batman-adv unicast 4 address header. While
the multicast-to-unicasts feature uses a simple, 3 address batman-adv
unicast header. So let's use this to distinguish.

Fixes: fe2da6ff27 ("batman-adv: check incoming packet type for bla")
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: Sasha Levin <sashal@kernel.org>
2020-10-01 13:14:52 +02:00
Sven Eckelmann
14d60e8488 batman-adv: Add missing include for in_interrupt()
[ Upstream commit 4bba9dab86b6ac15ca560ef1f2b5aa4529cbf784 ]

The fix for receiving (internally generated) bla packets outside the
interrupt context introduced the usage of in_interrupt(). But this
functionality is only defined in linux/preempt.h which was not included
with the same patch.

Fixes: 279e89b2281a ("batman-adv: bla: use netif_rx_ni when not in interrupt context")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:14:52 +02:00
Linus Lüssing
e63e927da2 batman-adv: mcast/TT: fix wrongly dropped or rerouted packets
[ Upstream commit 7dda5b3384121181c4e79f6eaeac2b94c0622c8d ]

The unicast packet rerouting code makes several assumptions. For
instance it assumes that there is always exactly one destination in the
TT. This breaks for multicast frames in a unicast packets in several ways:

For one thing if there is actually no TT entry and the destination node
was selected due to the multicast tvlv flags it announced. Then an
intermediate node will wrongly drop the packet.

For another thing if there is a TT entry but the TTVN of this entry is
newer than the originally addressed destination node: Then the
intermediate node will wrongly redirect the packet, leading to
duplicated multicast packets at a multicast listener and missing
packets at other multicast listeners or multicast routers.

Fixing this by not applying the unicast packet rerouting to batman-adv
unicast packets with a multicast payload. We are not able to detect a
roaming multicast listener at the moment and will just continue to send
the multicast frame to both the new and old destination for a while in
case of such a roaming multicast listener.

Fixes: a73105b8d4 ("batman-adv: improved client announcement mechanism")
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: Sasha Levin <sashal@kernel.org>
2020-10-01 13:14:51 +02:00
Linus Lüssing
8d6cd74552 batman-adv: bla: fix type misuse for backbone_gw hash indexing
[ Upstream commit 097930e85f90f252c44dc0d084598265dd44ca48 ]

It seems that due to a copy & paste error the void pointer
in batadv_choose_backbone_gw() is cast to the wrong type.

Fixing this by using "struct batadv_bla_backbone_gw" instead of "struct
batadv_bla_claim" which better matches the caller's side.

For now it seems that we were lucky because the two structs both have
their orig/vid and addr/vid in the beginning. However I stumbled over
this issue when I was trying to add some debug variables in front of
"orig" in batadv_backbone_gw, which caused hash lookups to fail.

Fixes: 07568d0369 ("batman-adv: don't rely on positions in struct for hashing")
Signed-off-by: Linus Lüssing <ll@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:14:51 +02:00
Jussi Kivilinna
3eabc73c4a batman-adv: bla: use netif_rx_ni when not in interrupt context
[ Upstream commit 279e89b2281af3b1a9f04906e157992c19c9f163 ]

batadv_bla_send_claim() gets called from worker thread context through
batadv_bla_periodic_work(), thus netif_rx_ni needs to be used in that
case. This fixes "NOHZ: local_softirq_pending 08" log messages seen
when batman-adv is enabled.

Fixes: 23721387c4 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@haltian.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-09 19:04:24 +02:00
Linus Lüssing
e6723a869a batman-adv: Fix own OGM check in aggregated OGMs
[ Upstream commit d8bf0c01642275c7dca1e5d02c34e4199c200b1f ]

The own OGM check is currently misplaced and can lead to the following
issues:

For one thing we might receive an aggregated OGM from a neighbor node
which has our own OGM in the first place. We would then not only skip
our own OGM but erroneously also any other, following OGM in the
aggregate.

For another, we might receive an OGM aggregate which has our own OGM in
a place other then the first one. Then we would wrongly not skip this
OGM, leading to populating the orginator and gateway table with ourself.

Fixes: 9323158ef9 ("batman-adv: OGMv2 - implement originators logic")
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: Sasha Levin <sashal@kernel.org>
2020-09-09 19:04:24 +02:00
Sven Eckelmann
1046c9a356 batman-adv: Avoid uninitialized chaddr when handling DHCP
[ Upstream commit 303216e76dcab6049c9d42390b1032f0649a8206 ]

The gateway client code can try to optimize the delivery of DHCP packets to
avoid broadcasting them through the whole mesh. But also transmissions to
the client can be optimized by looking up the destination via the chaddr of
the DHCP packet.

But the chaddr is currently only done when chaddr is fully inside the
non-paged area of the skbuff. Otherwise it will not be initialized and the
unoptimized path should have been taken.

But the implementation didn't handle this correctly. It didn't retrieve the
correct chaddr but still tried to perform the TT lookup with this
uninitialized memory.

Reported-by: syzbot+ab16e463b903f5a37036@syzkaller.appspotmail.com
Fixes: 6c413b1c22 ("batman-adv: send every DHCP packet as bat-unicast")
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: Sasha Levin <sashal@kernel.org>
2020-09-09 19:04:24 +02:00
Sven Eckelmann
f5dfbbee5d batman-adv: Revert "disable ethtool link speed detection when auto negotiation off"
[ Upstream commit 9ad346c90509ebd983f60da7d082f261ad329507 ]

The commit 8c46fcd783 ("batman-adv: disable ethtool link speed detection
when auto negotiation off") disabled the usage of ethtool's link_ksetting
when auto negotation was enabled due to invalid values when used with
tun/tap virtual net_devices. According to the patch, automatic measurements
should be used for these kind of interfaces.

But there are major flaws with this argumentation:

* automatic measurements are not implemented
* auto negotiation has nothing to do with the validity of the retrieved
  values

The first point has to be fixed by a longer patch series. The "validity"
part of the second point must be addressed in the same patch series by
dropping the usage of ethtool's link_ksetting (thus always doing automatic
measurements over ethernet).

Drop the patch again to have more default values for various net_device
types/configurations. The user can still overwrite them using the
batadv_hardif's BATADV_ATTR_THROUGHPUT_OVERRIDE.

Reported-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-22 09:05:12 +02:00
Xiyu Yang
529fab2033 batman-adv: Fix refcnt leak in batadv_v_ogm_process
commit 6f91a3f7af4186099dd10fa530dd7e0d9c29747d upstream.

batadv_v_ogm_process() invokes batadv_hardif_neigh_get(), which returns
a reference of the neighbor object to "hardif_neigh" with increased
refcount.

When batadv_v_ogm_process() returns, "hardif_neigh" becomes invalid, so
the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling paths of
batadv_v_ogm_process(). When batadv_v_ogm_orig_get() fails to get the
orig node and returns NULL, the refcnt increased by
batadv_hardif_neigh_get() is not decreased, causing a refcnt leak.

Fix this issue by jumping to "out" label when batadv_v_ogm_orig_get()
fails to get the orig node.

Fixes: 9323158ef9 ("batman-adv: OGMv2 - implement originators logic")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
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>
2020-05-14 07:57:22 +02:00
Xiyu Yang
b50dee7547 batman-adv: Fix refcnt leak in batadv_store_throughput_override
commit 6107c5da0fca8b50b4d3215e94d619d38cc4a18c upstream.

batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(),
which gets a batadv_hard_iface object from net_dev with increased refcnt
and its reference is assigned to a local pointer 'hard_iface'.

When batadv_store_throughput_override() returns, "hard_iface" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The issue happens in one error path of
batadv_store_throughput_override(). When batadv_parse_throughput()
returns NULL, the refcnt increased by batadv_hardif_get_by_netdev() is
not decreased, causing a refcnt leak.

Fix this issue by jumping to "out" label when batadv_parse_throughput()
returns NULL.

Fixes: 0b5ecc6811 ("batman-adv: add throughput override attribute to hard_ifaces")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
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>
2020-05-14 07:57:22 +02:00
Xiyu Yang
2668caa9c5 batman-adv: Fix refcnt leak in batadv_show_throughput_override
commit f872de8185acf1b48b954ba5bd8f9bc0a0d14016 upstream.

batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(),
which gets a batadv_hard_iface object from net_dev with increased refcnt
and its reference is assigned to a local pointer 'hard_iface'.

When batadv_show_throughput_override() returns, "hard_iface" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The issue happens in the normal path of
batadv_show_throughput_override(), which forgets to decrease the refcnt
increased by batadv_hardif_get_by_netdev() before the function returns,
causing a refcnt leak.

Fix this issue by calling batadv_hardif_put() before the
batadv_show_throughput_override() returns in the normal path.

Fixes: 0b5ecc6811 ("batman-adv: add throughput override attribute to hard_ifaces")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
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>
2020-05-14 07:57:21 +02:00
George Spelvin
ba47355d79 batman-adv: fix batadv_nc_random_weight_tq
commit fd0c42c4dea54335967c5a86f15fc064235a2797 upstream.

and change to pseudorandom numbers, as this is a traffic dithering
operation that doesn't need crypto-grade.

The previous code operated in 4 steps:

1. Generate a random byte 0 <= rand_tq <= 255
2. Multiply it by BATADV_TQ_MAX_VALUE - tq
3. Divide by 255 (= BATADV_TQ_MAX_VALUE)
4. Return BATADV_TQ_MAX_VALUE - rand_tq

This would apperar to scale (BATADV_TQ_MAX_VALUE - tq) by a random
value between 0/255 and 255/255.

But!  The intermediate value between steps 3 and 4 is stored in a u8
variable.  So it's truncated, and most of the time, is less than 255, after
which the division produces 0.  Specifically, if tq is odd, the product is
always even, and can never be 255.  If tq is even, there's exactly one
random byte value that will produce a product byte of 255.

Thus, the return value is 255 (511/512 of the time) or 254 (1/512
of the time).

If we assume that the truncation is a bug, and the code is meant to scale
the input, a simpler way of looking at it is that it's returning a random
value between tq and BATADV_TQ_MAX_VALUE, inclusive.

Well, we have an optimized function for doing just that.

Fixes: 3c12de9a5c ("batman-adv: network coding - code and transmit packets if possible")
Signed-off-by: George Spelvin <lkml@sdf.org>
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>
2020-05-14 07:57:21 +02:00
Sven Eckelmann
8562759c8f batman-adv: Avoid free/alloc race when handling OGM2 buffer
commit a8d23cbbf6c9f515ed678204ad2962be7c336344 upstream.

A B.A.T.M.A.N. V virtual interface has an OGM2 packet buffer which is
initialized using data from the 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 data is sent out or the functions modifying the
OGM2 buffer try to access already freed memory regions.

Fixes: 0da0035942 ("batman-adv: OGMv2 - add 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>
2020-03-18 07:14:25 +01:00
Sven Eckelmann
bf0ef794e1 batman-adv: Don't schedule OGM for disabled interface
commit 8e8ce08198de193e3d21d42e96945216e3d9ac7f upstream.

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: c6c8fea297 ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 07:14:22 +01:00
Sven Eckelmann
da319f060b batman-adv: Fix DAT candidate selection on little endian systems
commit 4cc4a1708903f404d2ca0dfde30e71e052c6cbc9 upstream.

The distributed arp table is using a DHT to store and retrieve MAC address
information for an IP address. This is done using unicast messages to
selected peers. The potential peers are looked up using the IP address and
the VID.

While the IP address is always stored in big endian byte order, this is not
the case of the VID. It can (depending on the host system) either be big
endian or little endian. The host must therefore always convert it to big
endian to ensure that all devices calculate the same peers for the same
lookup data.

Fixes: be1db4f661 ("batman-adv: make the Distributed ARP Table vlan aware")
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>
2020-01-23 08:21:34 +01:00
Sven Eckelmann
948e8eba65 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: c6c8fea297 ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06 13:06:22 +01:00
Sven Eckelmann
7d4201ff9f batman-adv: Only read OGM2 tvlv_len after buffer len check
[ Upstream commit 0ff0f15a32c093381ad1abc06abe85afb561ab28 ]

Multiple batadv_ogm2_packet can be stored in an skbuff. The functions
batadv_v_ogm_send_to_if() uses batadv_v_ogm_aggr_packet() to check if there
is another additional batadv_ogm2_packet in the skb or not before they
continue processing the packet.

The length for such an OGM2 is BATADV_OGM2_HLEN +
batadv_ogm2_packet->tvlv_len. The check must first check that at least
BATADV_OGM2_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: 9323158ef9 ("batman-adv: OGMv2 - implement originators logic")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-21 07:16:59 +02:00
Sven Eckelmann
86d5ae21d6 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: ef26157747 ("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>
2019-09-16 08:21:41 +02:00
Eric Dumazet
4b5fee4577 batman-adv: fix uninit-value in batadv_netlink_get_ifindex()
commit 3ee1bb7aae97324ec9078da1f00cb2176919563f upstream.

batadv_netlink_get_ifindex() needs to make sure user passed
a correct u32 attribute.

syzbot reported :
BUG: KMSAN: uninit-value in batadv_netlink_dump_hardif+0x70d/0x880 net/batman-adv/netlink.c:968
CPU: 1 PID: 11705 Comm: syz-executor888 Not tainted 5.1.0+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622
 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
 batadv_netlink_dump_hardif+0x70d/0x880 net/batman-adv/netlink.c:968
 genl_lock_dumpit+0xc6/0x130 net/netlink/genetlink.c:482
 netlink_dump+0xa84/0x1ab0 net/netlink/af_netlink.c:2253
 __netlink_dump_start+0xa3a/0xb30 net/netlink/af_netlink.c:2361
 genl_family_rcv_msg net/netlink/genetlink.c:550 [inline]
 genl_rcv_msg+0xfc1/0x1a40 net/netlink/genetlink.c:627
 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2486
 genl_rcv+0x63/0x80 net/netlink/genetlink.c:638
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x127e/0x12f0 net/netlink/af_netlink.c:1926
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:661 [inline]
 ___sys_sendmsg+0xcc6/0x1200 net/socket.c:2260
 __sys_sendmsg net/socket.c:2298 [inline]
 __do_sys_sendmsg net/socket.c:2307 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2305
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2305
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440209

Fixes: b60620cf56 ("batman-adv: netlink: hardif query")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
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>
2019-09-16 08:21:41 +02:00
Sven Eckelmann
909034b8ac batman-adv: Fix duplicated OGMs on NETDEV_UP
[ Upstream commit 9e6b5648bbc4cd48fab62cecbb81e9cc3c6e7e88 ]

The state of slave interfaces are handled differently depending on whether
the interface is up or not. All active interfaces (IFF_UP) will transmit
OGMs. But for B.A.T.M.A.N. IV, also non-active interfaces are scheduling
(low TTL) OGMs on active interfaces. The code which setups and schedules
the OGMs must therefore already be called when the interfaces gets added as
slave interface and the transmit function must then check whether it has to
send out the OGM or not on the specific slave interface.

But the commit f0d97253fb ("batman-adv: remove ogm_emit and ogm_schedule
API calls") moved the setup code from the enable function to the activate
function. The latter is called either when the added slave was already up
when batadv_hardif_enable_interface processed the new interface or when a
NETDEV_UP event was received for this slave interfac. As result, each
NETDEV_UP would schedule a new OGM worker for the interface and thus OGMs
would be send a lot more than expected.

Fixes: f0d97253fb ("batman-adv: remove ogm_emit and ogm_schedule API calls")
Reported-by: Linus Lüssing <linus.luessing@c0d3.blue>
Tested-by: Linus Lüssing <linus.luessing@c0d3.blue>
Acked-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: Sasha Levin <sashal@kernel.org>
2019-07-26 09:14:03 +02:00
Jeremy Sowden
8f855c09e2 batman-adv: fix for leaked TVLV handler.
[ Upstream commit 17f78dd1bd624a4dd78ed5db3284a63ee807fcc3 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-26 09:13:59 +02:00
Linus Lüssing
25204fe6a3 batman-adv: allow updating DAT entry timeouts on incoming ARP Replies
[ Upstream commit 099e6cc1582dc2903fecb898bbeae8f7cf4262c7 ]

Currently incoming ARP Replies, for example via a DHT-PUT message, do
not update the timeout for an already existing DAT entry. These ARP
Replies are dropped instead.

This however defeats the purpose of the DHCPACK snooping, for instance.
Right now, a DAT entry in the DHT will be purged every five minutes,
likely leading to a mesh-wide ARP Request broadcast after this timeout.
Which then recreates the entry. The idea of the DHCPACK snooping is to
be able to update an entry before a timeout happens, to avoid ARP Request
flooding.

This patch fixes this issue by updating a DAT entry on incoming
ARP Replies even if a matching DAT entry already exists. While still
filtering the ARP Reply towards the soft-interface, to avoid duplicate
messages on the client device side.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:31 -07:00
Linus Lüssing
363aa80a51 batman-adv: mcast: fix multicast tt/tvlv worker locking
commit a3c7cd0cdf1107f891aff847ad481e34df727055 upstream.

Syzbot has reported some issues with the locking assumptions made for
the multicast tt/tvlv worker: It was able to trigger the WARN_ON() in
batadv_mcast_mla_tt_retract() and batadv_mcast_mla_tt_add().
While hard/not reproduceable for us so far it seems that the
delayed_work_pending() we use might not be quite safe from reordering.

Therefore this patch adds an explicit, new spinlock to protect the
update of the mla_list and flags in bat_priv and then removes the
WARN_ON(delayed_work_pending()).

Reported-by: syzbot+83f2d54ec6b7e417e13f@syzkaller.appspotmail.com
Reported-by: syzbot+050927a651272b145a5d@syzkaller.appspotmail.com
Reported-by: syzbot+979ffc89b87309b1b94b@syzkaller.appspotmail.com
Reported-by: syzbot+f9f3f388440283da2965@syzkaller.appspotmail.com
Fixes: cbebd363b2 ("batman-adv: Use own timer for multicast TT and TVLV updates")
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31 06:46:05 -07:00
Anders Roxell
894b4fc043 batman-adv: fix warning in function batadv_v_elp_get_throughput
[ Upstream commit ca8c3b922e7032aff6cc3fd05548f4df1f3df90e ]

When CONFIG_CFG80211 isn't enabled the compiler correcly warns about
'sinfo.pertid' may be unused. It can also happen for other error
conditions that it not warn about.

net/batman-adv/bat_v_elp.c: In function ‘batadv_v_elp_get_throughput.isra.0’:
include/net/cfg80211.h:6370:13: warning: ‘sinfo.pertid’ may be used
 uninitialized in this function [-Wmaybe-uninitialized]
  kfree(sinfo->pertid);
        ~~~~~^~~~~~~~

Rework so that we only release '&sinfo' if cfg80211_get_station returns
zero.

Fixes: 7d652669b61d ("batman-adv: release station info tidstats")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-08 07:21:46 +02:00
Sven Eckelmann
7afe374cc7 batman-adv: Reduce tt_global hash refcnt only for removed entry
[ Upstream commit f131a56880d10932931e74773fb8702894a94a75 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-08 07:21:46 +02:00
Sven Eckelmann
6957021da7 batman-adv: Reduce tt_local hash refcnt only for removed entry
[ Upstream commit 3d65b9accab4a7ed5038f6df403fbd5e298398c7 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-08 07:21:46 +02:00
Sven Eckelmann
be807f9b4f batman-adv: Reduce claim hash refcnt only for removed entry
[ Upstream commit 4ba104f468bbfc27362c393815d03aa18fb7a20f ]

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: 23721387c4 ("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: Sasha Levin <sashal@kernel.org>
2019-05-08 07:21:46 +02:00
Felix Fietkau
f7e3fb0a6f batman-adv: release station info tidstats
[ Upstream commit 7d652669b61d702c6e62a39579d17f6881670ab6 ]

With the addition of TXQ stats in the per-tid statistics the struct
station_info grew significantly. This resulted in stack size warnings
due to the structure itself being above the limit for the warnings.

To work around this, the TID array was allocated dynamically. Also a
function to free this content was introduced with commit 7ea3e110f2
("cfg80211: release station info tidstats where needed") but the necessary
changes were not provided for batman-adv's B.A.T.M.A.N. V implementation.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Fixes: 8689c051a2 ("cfg80211: dynamically allocate per-tid stats for station info")
[sven@narfation.org: add commit message]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:02:34 -07:00
Eric Dumazet
c580bb3120 batman-adv: fix uninit-value in batadv_interface_tx()
[ Upstream commit 4ffcbfac60642f63ae3d80891f573ba7e94a265c ]

KMSAN reported batadv_interface_tx() was possibly using a
garbage value [1]

batadv_get_vid() does have a pskb_may_pull() call
but batadv_interface_tx() does not actually make sure
this did not fail.

[1]
BUG: KMSAN: uninit-value in batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
CPU: 0 PID: 10006 Comm: syz-executor469 Not tainted 4.20.0-rc7+ #5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
 batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
 __netdev_start_xmit include/linux/netdevice.h:4356 [inline]
 netdev_start_xmit include/linux/netdevice.h:4365 [inline]
 xmit_one net/core/dev.c:3257 [inline]
 dev_hard_start_xmit+0x607/0xc40 net/core/dev.c:3273
 __dev_queue_xmit+0x2e42/0x3bc0 net/core/dev.c:3843
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3876
 packet_snd net/packet/af_packet.c:2928 [inline]
 packet_sendmsg+0x8306/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x441889
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdda6fd468 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000441889
RDX: 000000000000000e RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00007ffdda6fd4c0
R13: 00007ffdda6fd4b0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2759 [inline]
 __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383
 __kmalloc_reserve net/core/skbuff.c:137 [inline]
 __alloc_skb+0x309/0xa20 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:998 [inline]
 alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5220
 sock_alloc_send_pskb+0xafd/0x10e0 net/core/sock.c:2083
 packet_alloc_skb net/packet/af_packet.c:2781 [inline]
 packet_snd net/packet/af_packet.c:2872 [inline]
 packet_sendmsg+0x661a/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc:	Marek Lindner <mareklindner@neomailbox.ch>
Cc:	Simon Wunderlich <sw@simonwunderlich.de>
Cc:	Antonio Quartulli <a@unstable.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-27 10:08:58 +01:00
Sven Eckelmann
4dd911f1e3 batman-adv: Force mac header to start of data on xmit
commit 9114daa825fc3f335f9bea3313ce667090187280 upstream.

The caller of ndo_start_xmit may not already have called
skb_reset_mac_header. The returned value of skb_mac_header/eth_hdr
therefore can be in the wrong position and even outside the current skbuff.
This for example happens when the user binds to the device using a
PF_PACKET-SOCK_RAW with enabled qdisc-bypass:

  int opt = 4;
  setsockopt(sock, SOL_PACKET, PACKET_QDISC_BYPASS, &opt, sizeof(opt));

Since eth_hdr is used all over the codebase, the batadv_interface_tx
function must always take care of resetting it.

Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Reported-by: syzbot+9d7405c7faa390e60b4e@syzkaller.appspotmail.com
Reported-by: syzbot+7d20bc3f1ddddc0f9079@syzkaller.appspotmail.com
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>
2019-02-15 08:10:13 +01:00
Sven Eckelmann
a212223050 batman-adv: Avoid WARN on net_device without parent in netns
commit 955d3411a17f590364238bd0d3329b61f20c1cd2 upstream.

It is not allowed to use WARN* helpers on potential incorrect input from
the user or transient problems because systems configured as panic_on_warn
will reboot due to such a problem.

A NULL return value of __dev_get_by_index can be caused by various problems
which can either be related to the system configuration or problems
(incorrectly returned network namespaces) in other (virtual) net_device
drivers. batman-adv should not cause a (harmful) WARN in this situation and
instead only report it via a simple message.

Fixes: b7eddd0b39 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface")
Reported-by: syzbot+c764de0fcfadca9a8595@syzkaller.appspotmail.com
Reported-by: Dmitry Vyukov <dvyukov@google.com>
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>
2019-02-15 08:10:13 +01:00