1954 Commits

Author SHA1 Message Date
Felix Fietkau
2c110b4520 net: bridge: fix corrupted ethernet header on multicast-to-unicast
[ Upstream commit 86b29d830ad69eecff25b22dc96c14c6573718e6 ]

The change from skb_copy to pskb_copy unfortunately changed the data
copying to omit the ethernet header, since it was pulled before reaching
this point. Fix this by calling __skb_push/pull around pskb_copy.

Fixes: 59c878cbcdd8 ("net: bridge: fix multicast-to-unicast with fraglist GSO")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:43:54 +02:00
Felix Fietkau
4945c046ae net: bridge: fix multicast-to-unicast with fraglist GSO
[ Upstream commit 59c878cbcdd80ed39315573b3511d0acfd3501b5 ]

Calling skb_copy on a SKB_GSO_FRAGLIST skb is not valid, since it returns
an invalid linearized skb. This code only needs to change the ethernet
header, so pskb_copy is the right function to call here.

Fixes: 6db6f0eae605 ("bridge: multicast to unicast")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:43:49 +02:00
Nikolay Aleksandrov
81e03f638d net: bridge: clear bridge's private skb space on xmit
[ Upstream commit fd65e5a95d08389444e8591a20538b3edece0e15 ]

We need to clear all of the bridge private skb variables as they can be
stale due to the packet being recirculated through the stack and then
transmitted through the bridge device. Similar memset is already done on
bridge's input. We've seen cases where proxyarp_replied was 1 on routed
multicast packets transmitted through the bridge to ports with neigh
suppress which were getting dropped. Same thing can in theory happen with
the port isolation bit as well.

Fixes: 821f1b21cabb ("bridge: add new BR_NEIGH_SUPPRESS port flag to suppress arp and nd flood")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:13:35 +01:00
Linkui Xiao
b2762d13df netfilter: nf_conntrack_bridge: initialize err to 0
[ Upstream commit a44af08e3d4d7566eeea98d7a29fe06e7b9de944 ]

K2CI reported a problem:

	consume_skb(skb);
	return err;
[nf_br_ip_fragment() error]  uninitialized symbol 'err'.

err is not initialized, because returning 0 is expected, initialize err
to 0.

Fixes: 3c171f496ef5 ("netfilter: bridge: add connection tracking system")
Reported-by: k2ci <kernel-bot@kylinos.cn>
Signed-off-by: Linkui Xiao <xiaolinkui@kylinos.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 16:50:17 +00:00
Eric Dumazet
ad8d39c7b4 net: bridge: use DEV_STATS_INC()
[ Upstream commit 44bdb313da57322c9b3c108eb66981c6ec6509f4 ]

syzbot/KCSAN reported data-races in br_handle_frame_finish() [1]
This function can run from multiple cpus without mutual exclusion.

Adopt SMP safe DEV_STATS_INC() to update dev->stats fields.

Handles updates to dev->stats.tx_dropped while we are at it.

[1]
BUG: KCSAN: data-race in br_handle_frame_finish / br_handle_frame_finish

read-write to 0xffff8881374b2178 of 8 bytes by interrupt on cpu 1:
br_handle_frame_finish+0xd4f/0xef0 net/bridge/br_input.c:189
br_nf_hook_thresh+0x1ed/0x220
br_nf_pre_routing_finish_ipv6+0x50f/0x540
NF_HOOK include/linux/netfilter.h:304 [inline]
br_nf_pre_routing_ipv6+0x1e3/0x2a0 net/bridge/br_netfilter_ipv6.c:178
br_nf_pre_routing+0x526/0xba0 net/bridge/br_netfilter_hooks.c:508
nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:272 [inline]
br_handle_frame+0x4c9/0x940 net/bridge/br_input.c:417
__netif_receive_skb_core+0xa8a/0x21e0 net/core/dev.c:5417
__netif_receive_skb_one_core net/core/dev.c:5521 [inline]
__netif_receive_skb+0x57/0x1b0 net/core/dev.c:5637
process_backlog+0x21f/0x380 net/core/dev.c:5965
__napi_poll+0x60/0x3b0 net/core/dev.c:6527
napi_poll net/core/dev.c:6594 [inline]
net_rx_action+0x32b/0x750 net/core/dev.c:6727
__do_softirq+0xc1/0x265 kernel/softirq.c:553
run_ksoftirqd+0x17/0x20 kernel/softirq.c:921
smpboot_thread_fn+0x30a/0x4a0 kernel/smpboot.c:164
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

read-write to 0xffff8881374b2178 of 8 bytes by interrupt on cpu 0:
br_handle_frame_finish+0xd4f/0xef0 net/bridge/br_input.c:189
br_nf_hook_thresh+0x1ed/0x220
br_nf_pre_routing_finish_ipv6+0x50f/0x540
NF_HOOK include/linux/netfilter.h:304 [inline]
br_nf_pre_routing_ipv6+0x1e3/0x2a0 net/bridge/br_netfilter_ipv6.c:178
br_nf_pre_routing+0x526/0xba0 net/bridge/br_netfilter_hooks.c:508
nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:272 [inline]
br_handle_frame+0x4c9/0x940 net/bridge/br_input.c:417
__netif_receive_skb_core+0xa8a/0x21e0 net/core/dev.c:5417
__netif_receive_skb_one_core net/core/dev.c:5521 [inline]
__netif_receive_skb+0x57/0x1b0 net/core/dev.c:5637
process_backlog+0x21f/0x380 net/core/dev.c:5965
__napi_poll+0x60/0x3b0 net/core/dev.c:6527
napi_poll net/core/dev.c:6594 [inline]
net_rx_action+0x32b/0x750 net/core/dev.c:6727
__do_softirq+0xc1/0x265 kernel/softirq.c:553
do_softirq+0x5e/0x90 kernel/softirq.c:454
__local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_local_purge+0x1a8/0x1f0 net/batman-adv/translation-table.c:1356
batadv_tt_purge+0x2b/0x630 net/batman-adv/translation-table.c:3560
process_one_work kernel/workqueue.c:2630 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
worker_thread+0x525/0x730 kernel/workqueue.c:2784
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

value changed: 0x00000000000d7190 -> 0x00000000000d7191

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14848 Comm: kworker/u4:11 Not tainted 6.6.0-rc1-syzkaller-00236-gad8a69f361b9 #0

Fixes: 1c29fc4989bc ("[BRIDGE]: keep track of received multicast packets")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: bridge@lists.linux-foundation.org
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230918091351.1356153-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 21:46:37 +02:00
Vladimir Oltean
e9c2687988 net: bridge: keep ports without IFF_UNICAST_FLT in BR_PROMISC mode
[ Upstream commit 6ca3c005d0604e8d2b439366e3923ea58db99641 ]

According to the synchronization rules for .ndo_get_stats() as seen in
Documentation/networking/netdevices.rst, acquiring a plain spin_lock()
should not be illegal, but the bridge driver implementation makes it so.

After running these commands, I am being faced with the following
lockdep splat:

$ ip link add link swp0 name macsec0 type macsec encrypt on && ip link set swp0 up
$ ip link add dev br0 type bridge vlan_filtering 1 && ip link set br0 up
$ ip link set macsec0 master br0 && ip link set macsec0 up

  ========================================================
  WARNING: possible irq lock inversion dependency detected
  6.4.0-04295-g31b577b4bd4a #603 Not tainted
  --------------------------------------------------------
  swapper/1/0 just changed the state of lock:
  ffff6bd348724cd8 (&br->lock){+.-.}-{3:3}, at: br_forward_delay_timer_expired+0x34/0x198
  but this lock took another, SOFTIRQ-unsafe lock in the past:
   (&ocelot->stats_lock){+.+.}-{3:3}

  and interrupts could create inverse lock ordering between them.

  other info that might help us debug this:
  Chain exists of:
    &br->lock --> &br->hash_lock --> &ocelot->stats_lock

   Possible interrupt unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&ocelot->stats_lock);
                                 local_irq_disable();
                                 lock(&br->lock);
                                 lock(&br->hash_lock);
    <Interrupt>
      lock(&br->lock);

   *** DEADLOCK ***

(details about the 3 locks skipped)

swp0 is instantiated by drivers/net/dsa/ocelot/felix.c, and this
only matters to the extent that its .ndo_get_stats64() method calls
spin_lock(&ocelot->stats_lock).

Documentation/locking/lockdep-design.rst says:

| A lock is irq-safe means it was ever used in an irq context, while a lock
| is irq-unsafe means it was ever acquired with irq enabled.

(...)

| Furthermore, the following usage based lock dependencies are not allowed
| between any two lock-classes::
|
|    <hardirq-safe>   ->  <hardirq-unsafe>
|    <softirq-safe>   ->  <softirq-unsafe>

Lockdep marks br->hash_lock as softirq-safe, because it is sometimes
taken in softirq context (for example br_fdb_update() which runs in
NET_RX softirq), and when it's not in softirq context it blocks softirqs
by using spin_lock_bh().

Lockdep marks ocelot->stats_lock as softirq-unsafe, because it never
blocks softirqs from running, and it is never taken from softirq
context. So it can always be interrupted by softirqs.

There is a call path through which a function that holds br->hash_lock:
fdb_add_hw_addr() will call a function that acquires ocelot->stats_lock:
ocelot_port_get_stats64(). This can be seen below:

ocelot_port_get_stats64+0x3c/0x1e0
felix_get_stats64+0x20/0x38
dsa_slave_get_stats64+0x3c/0x60
dev_get_stats+0x74/0x2c8
rtnl_fill_stats+0x4c/0x150
rtnl_fill_ifinfo+0x5cc/0x7b8
rtmsg_ifinfo_build_skb+0xe4/0x150
rtmsg_ifinfo+0x5c/0xb0
__dev_notify_flags+0x58/0x200
__dev_set_promiscuity+0xa0/0x1f8
dev_set_promiscuity+0x30/0x70
macsec_dev_change_rx_flags+0x68/0x88
__dev_set_promiscuity+0x1a8/0x1f8
__dev_set_rx_mode+0x74/0xa8
dev_uc_add+0x74/0xa0
fdb_add_hw_addr+0x68/0xd8
fdb_add_local+0xc4/0x110
br_fdb_add_local+0x54/0x88
br_add_if+0x338/0x4a0
br_add_slave+0x20/0x38
do_setlink+0x3a4/0xcb8
rtnl_newlink+0x758/0x9d0
rtnetlink_rcv_msg+0x2f0/0x550
netlink_rcv_skb+0x128/0x148
rtnetlink_rcv+0x24/0x38

the plain English explanation for it is:

The macsec0 bridge port is created without p->flags & BR_PROMISC,
because it is what br_manage_promisc() decides for a VLAN filtering
bridge with a single auto port.

As part of the br_add_if() procedure, br_fdb_add_local() is called for
the MAC address of the device, and this results in a call to
dev_uc_add() for macsec0 while the softirq-safe br->hash_lock is taken.

Because macsec0 does not have IFF_UNICAST_FLT, dev_uc_add() ends up
calling __dev_set_promiscuity() for macsec0, which is propagated by its
implementation, macsec_dev_change_rx_flags(), to the lower device: swp0.
This triggers the call path:

dev_set_promiscuity(swp0)
-> rtmsg_ifinfo()
   -> dev_get_stats()
      -> ocelot_port_get_stats64()

with a calling context that lockdep doesn't like (br->hash_lock held).

Normally we don't see this, because even though many drivers that can be
bridge ports don't support IFF_UNICAST_FLT, we need a driver that

(a) doesn't support IFF_UNICAST_FLT, *and*
(b) it forwards the IFF_PROMISC flag to another driver, and
(c) *that* driver implements ndo_get_stats64() using a softirq-unsafe
    spinlock.

Condition (b) is necessary because the first __dev_set_rx_mode() calls
__dev_set_promiscuity() with "bool notify=false", and thus, the
rtmsg_ifinfo() code path won't be entered.

The same criteria also hold true for DSA switches which don't report
IFF_UNICAST_FLT. When the DSA master uses a spin_lock() in its
ndo_get_stats64() method, the same lockdep splat can be seen.

I think the deadlock possibility is real, even though I didn't reproduce
it, and I'm thinking of the following situation to support that claim:

fdb_add_hw_addr() runs on a CPU A, in a context with softirqs locally
disabled and br->hash_lock held, and may end up attempting to acquire
ocelot->stats_lock.

In parallel, ocelot->stats_lock is currently held by a thread B (say,
ocelot_check_stats_work()), which is interrupted while holding it by a
softirq which attempts to lock br->hash_lock.

Thread B cannot make progress because br->hash_lock is held by A. Whereas
thread A cannot make progress because ocelot->stats_lock is held by B.

When taking the issue at face value, the bridge can avoid that problem
by simply making the ports promiscuous from a code path with a saner
calling context (br->hash_lock not held). A bridge port without
IFF_UNICAST_FLT is going to become promiscuous as soon as we call
dev_uc_add() on it (which we do unconditionally), so why not be
preemptive and make it promiscuous right from the beginning, so as to
not be taken by surprise.

With this, we've broken the links between code that holds br->hash_lock
or br->lock and code that calls into the ndo_change_rx_flags() or
ndo_get_stats64() ops of the bridge port.

Fixes: 2796d0c648c9 ("bridge: Automatically manage port promiscuous mode.")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:37:23 +02:00
Pablo Neira Ayuso
7c788393d4 netfilter: nftables: add nft_parse_register_store() and use it
[ 345023b0db315648ccc3c1a36aee88304a8b4d91 ]

This new function combines the netlink register attribute parser
and the store validation function.

This update requires to replace:

        enum nft_registers      dreg:8;

in many of the expression private areas otherwise compiler complains
with:

        error: cannot take address of bit-field ‘dreg’

when passing the register field as reference.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-30 12:44:07 +01:00
Eric Dumazet
4188c52694 net: add vlan_get_protocol_and_depth() helper
[ Upstream commit 4063384ef762cc5946fc7a3f89879e76c6ec51e2 ]

Before blamed commit, pskb_may_pull() was used instead
of skb_header_pointer() in __vlan_get_protocol() and friends.

Few callers depended on skb->head being populated with MAC header,
syzbot caught one of them (skb_mac_gso_segment())

Add vlan_get_protocol_and_depth() to make the intent clearer
and use it where sensible.

This is a more generic fix than commit e9d3f80935b6
("net/af_packet: make sure to pull mac header") which was
dealing with a similar issue.

kernel BUG at include/linux/skbuff.h:2655 !
invalid opcode: 0000 [#1] SMP KASAN
CPU: 0 PID: 1441 Comm: syz-executor199 Not tainted 6.1.24-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
RIP: 0010:__skb_pull include/linux/skbuff.h:2655 [inline]
RIP: 0010:skb_mac_gso_segment+0x68f/0x6a0 net/core/gro.c:136
Code: fd 48 8b 5c 24 10 44 89 6b 70 48 c7 c7 c0 ae 0d 86 44 89 e6 e8 a1 91 d0 00 48 c7 c7 00 af 0d 86 48 89 de 31 d2 e8 d1 4a e9 ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
RSP: 0018:ffffc90001bd7520 EFLAGS: 00010286
RAX: ffffffff8469736a RBX: ffff88810f31dac0 RCX: ffff888115a18b00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90001bd75e8 R08: ffffffff84697183 R09: fffff5200037adf9
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000012
R13: 000000000000fee5 R14: 0000000000005865 R15: 000000000000fed7
FS: 000055555633f300(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 0000000116fea000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
[<ffffffff847018dd>] __skb_gso_segment+0x32d/0x4c0 net/core/dev.c:3419
[<ffffffff8470398a>] skb_gso_segment include/linux/netdevice.h:4819 [inline]
[<ffffffff8470398a>] validate_xmit_skb+0x3aa/0xee0 net/core/dev.c:3725
[<ffffffff84707042>] __dev_queue_xmit+0x1332/0x3300 net/core/dev.c:4313
[<ffffffff851a9ec7>] dev_queue_xmit+0x17/0x20 include/linux/netdevice.h:3029
[<ffffffff851b4a82>] packet_snd net/packet/af_packet.c:3111 [inline]
[<ffffffff851b4a82>] packet_sendmsg+0x49d2/0x6470 net/packet/af_packet.c:3142
[<ffffffff84669a12>] sock_sendmsg_nosec net/socket.c:716 [inline]
[<ffffffff84669a12>] sock_sendmsg net/socket.c:736 [inline]
[<ffffffff84669a12>] __sys_sendto+0x472/0x5f0 net/socket.c:2139
[<ffffffff84669c75>] __do_sys_sendto net/socket.c:2151 [inline]
[<ffffffff84669c75>] __se_sys_sendto net/socket.c:2147 [inline]
[<ffffffff84669c75>] __x64_sys_sendto+0xe5/0x100 net/socket.c:2147
[<ffffffff8551d40f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff8551d40f>] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80
[<ffffffff85600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 469aceddfa3e ("vlan: consolidate VLAN parsing code and limit max parsing depth")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Cc: Willem de Bruijn <willemb@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-30 12:44:01 +01:00
Florian Westphal
36f098e1e4 netfilter: br_netfilter: fix recent physdev match breakage
[ Upstream commit 94623f579ce338b5fa61b5acaa5beb8aa657fb9e ]

Recent attempt to ensure PREROUTING hook is executed again when a
decrypted ipsec packet received on a bridge passes through the network
stack a second time broke the physdev match in INPUT hook.

We can't discard the nf_bridge info strct from sabotage_in hook, as
this is needed by the physdev match.

Keep the struct around and handle this with another conditional instead.

Fixes: 2b272bb558f1 ("netfilter: br_netfilter: disable sabotage_in hook after first suppression")
Reported-and-tested-by: Farid BENAMROUCHE <fariouche@yahoo.fr>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-26 11:24:01 +02:00
Florian Westphal
dffe83a198 netfilter: br_netfilter: disable sabotage_in hook after first suppression
[ Upstream commit 2b272bb558f1d3a5aa95ed8a82253786fd1a48ba ]

When using a xfrm interface in a bridged setup (the outgoing device is
bridged), the incoming packets in the xfrm interface are only tracked
in the outgoing direction.

$ brctl show
bridge name     interfaces
br_eth1         eth1

$ conntrack -L
tcp 115 SYN_SENT src=192... dst=192... [UNREPLIED] ...

If br_netfilter is enabled, the first (encrypted) packet is received onR
eth1, conntrack hooks are called from br_netfilter emulation which
allocates nf_bridge info for this skb.

If the packet is for local machine, skb gets passed up the ip stack.
The skb passes through ip prerouting a second time. br_netfilter
ip_sabotage_in supresses the re-invocation of the hooks.

After this, skb gets decrypted in xfrm layer and appears in
network stack a second time (after decryption).

Then, ip_sabotage_in is called again and suppresses netfilter
hook invocation, even though the bridge layer never called them
for the plaintext incarnation of the packet.

Free the bridge info after the first suppression to avoid this.

I was unable to figure out where the regression comes from, as far as i
can see br_netfilter always had this problem; i did not expect that skb
is looped again with different headers.

Fixes: c4b0e771f906 ("netfilter: avoid using skb->nf_bridge directly")
Reported-and-tested-by: Wolfgang Nothdurft <wolfgang@linogate.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-22 12:50:24 +01:00
Florian Westphal
11ebf32fde netfilter: ebtables: fix memory leak when blob is malformed
[ Upstream commit 62ce44c4fff947eebdf10bb582267e686e6835c9 ]

The bug fix was incomplete, it "replaced" crash with a memory leak.
The old code had an assignment to "ret" embedded into the conditional,
restore this.

Fixes: 7997eff82828 ("netfilter: ebtables: reject blobs that don't provide all entry points")
Reported-and-tested-by: syzbot+a24c5252f3e3ab733464@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:04:07 +02:00
Harsh Modi
323b6847e5 netfilter: br_netfilter: Drop dst references before setting.
[ Upstream commit d047283a7034140ea5da759a494fd2274affdd46 ]

The IPv6 path already drops dst in the daddr changed case, but the IPv4
path does not. This change makes the two code paths consistent.

Further, it is possible that there is already a metadata_dst allocated from
ingress that might already be attached to skbuff->dst while following
the bridge path. If it is not released before setting a new
metadata_dst, it will be leaked. This is similar to what is done in
bpf_set_tunnel_key() or ip6_route_input().

It is important to note that the memory being leaked is not the dst
being set in the bridge code, but rather memory allocated from some
other code path that is not being freed correctly before the skb dst is
overwritten.

An example of the leakage fixed by this commit found using kmemleak:

unreferenced object 0xffff888010112b00 (size 256):
  comm "softirq", pid 0, jiffies 4294762496 (age 32.012s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 80 16 f1 83 ff ff ff ff  ................
    e1 4e f6 82 ff ff ff ff 00 00 00 00 00 00 00 00  .N..............
  backtrace:
    [<00000000d79567ea>] metadata_dst_alloc+0x1b/0xe0
    [<00000000be113e13>] udp_tun_rx_dst+0x174/0x1f0
    [<00000000a36848f4>] geneve_udp_encap_recv+0x350/0x7b0
    [<00000000d4afb476>] udp_queue_rcv_one_skb+0x380/0x560
    [<00000000ac064aea>] udp_unicast_rcv_skb+0x75/0x90
    [<000000009a8ee8c5>] ip_protocol_deliver_rcu+0xd8/0x230
    [<00000000ef4980bb>] ip_local_deliver_finish+0x7a/0xa0
    [<00000000d7533c8c>] __netif_receive_skb_one_core+0x89/0xa0
    [<00000000a879497d>] process_backlog+0x93/0x190
    [<00000000e41ade9f>] __napi_poll+0x28/0x170
    [<00000000b4c0906b>] net_rx_action+0x14f/0x2a0
    [<00000000b20dd5d4>] __do_softirq+0xf4/0x305
    [<000000003a7d7e15>] __irq_exit_rcu+0xc3/0x140
    [<00000000968d39a2>] sysvec_apic_timer_interrupt+0x9e/0xc0
    [<000000009e920794>] asm_sysvec_apic_timer_interrupt+0x16/0x20
    [<000000008942add0>] native_safe_halt+0x13/0x20

Florian Westphal says: "Original code was likely fine because nothing
ever did set a skb->dst entry earlier than bridge in those days."

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Harsh Modi <harshmodi@google.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 12:04:55 +02:00
Florian Westphal
160c4eb47d netfilter: ebtables: reject blobs that don't provide all entry points
[ Upstream commit 7997eff82828304b780dc0a39707e1946d6f1ebf ]

Harshit Mogalapalli says:
 In ebt_do_table() function dereferencing 'private->hook_entry[hook]'
 can lead to NULL pointer dereference. [..] Kernel panic:

general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
[..]
RIP: 0010:ebt_do_table+0x1dc/0x1ce0
Code: 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 5c 16 00 00 48 b8 00 00 00 00 00 fc ff df 49 8b 6c df 08 48 8d 7d 2c 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 88
[..]
Call Trace:
 nf_hook_slow+0xb1/0x170
 __br_forward+0x289/0x730
 maybe_deliver+0x24b/0x380
 br_flood+0xc6/0x390
 br_dev_xmit+0xa2e/0x12c0

For some reason ebtables rejects blobs that provide entry points that are
not supported by the table, but what it should instead reject is the
opposite: blobs that DO NOT provide an entry point supported by the table.

t->valid_hooks is the bitmask of hooks (input, forward ...) that will see
packets.  Providing an entry point that is not support is harmless
(never called/used), but the inverse isn't: it results in a crash
because the ebtables traverser doesn't expect a NULL blob for a location
its receiving packets for.

Instead of fixing all the individual checks, do what iptables is doing and
reject all blobs that differ from the expected hooks.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-05 10:27:41 +02:00
Florian Westphal
b749af1b8f netfilter: br_netfilter: do not skip all hooks with 0 priority
[ Upstream commit c2577862eeb0be94f151f2f1fff662b028061b00 ]

When br_netfilter module is loaded, skbs may be diverted to the
ipv4/ipv6 hooks, just like as if we were routing.

Unfortunately, bridge filter hooks with priority 0 may be skipped
in this case.

Example:
1. an nftables bridge ruleset is loaded, with a prerouting
   hook that has priority 0.
2. interface is added to the bridge.
3. no tcp packet is ever seen by the bridge prerouting hook.
4. flush the ruleset
5. load the bridge ruleset again.
6. tcp packets are processed as expected.

After 1) the only registered hook is the bridge prerouting hook, but its
not called yet because the bridge hasn't been brought up yet.

After 2), hook order is:
   0 br_nf_pre_routing // br_netfilter internal hook
   0 chain bridge f prerouting // nftables bridge ruleset

The packet is diverted to br_nf_pre_routing.
If call-iptables is off, the nftables bridge ruleset is called as expected.

But if its enabled, br_nf_hook_thresh() will skip it because it assumes
that all 0-priority hooks had been called previously in bridge context.

To avoid this, check for the br_nf_pre_routing hook itself, we need to
resume directly after it, even if this hook has a priority of 0.

Unfortunately, this still results in different packet flow.
With this fix, the eval order after in 3) is:
1. br_nf_pre_routing
2. ip(6)tables (if enabled)
3. nftables bridge

but after 5 its the much saner:
1. nftables bridge
2. br_nf_pre_routing
3. ip(6)tables (if enabled)

Unfortunately I don't see a solution here:
It would be possible to move br_nf_pre_routing to a higher priority
so that it will be called later in the pipeline, but this also impacts
ebtables evaluation order, and would still result in this very ordering
problem for all nftables-bridge hooks with the same priority as the
br_nf_pre_routing one.

Searching back through the git history I don't think this has
ever behaved in any other way, hence, no fixes-tag.

Reported-by: Radim Hrazdil <rhrazdil@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21 20:59:24 +02:00
Andrew Lunn
1fe6dc5f5d net: bridge: Clear offload_fwd_mark when passing frame up bridge interface.
[ Upstream commit fbb3abdf2223cd0dfc07de85fe5a43ba7f435bdf ]

It is possible to stack bridges on top of each other. Consider the
following which makes use of an Ethernet switch:

       br1
     /    \
    /      \
   /        \
 br0.11    wlan0
   |
   br0
 /  |  \
p1  p2  p3

br0 is offloaded to the switch. Above br0 is a vlan interface, for
vlan 11. This vlan interface is then a slave of br1. br1 also has a
wireless interface as a slave. This setup trunks wireless lan traffic
over the copper network inside a VLAN.

A frame received on p1 which is passed up to the bridge has the
skb->offload_fwd_mark flag set to true, indicating that the switch has
dealt with forwarding the frame out ports p2 and p3 as needed. This
flag instructs the software bridge it does not need to pass the frame
back down again. However, the flag is not getting reset when the frame
is passed upwards. As a result br1 sees the flag, wrongly interprets
it, and fails to forward the frame to wlan0.

When passing a frame upwards, clear the flag. This is the Rx
equivalent of br_switchdev_frame_unmark() in br_dev_xmit().

Fixes: f1c2eddf4cb6 ("bridge: switchdev: Use an helper to clear forward mark")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20220518005840.771575-1-andrew@lunn.ch
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:14:36 +02:00
Nikolay Aleksandrov
b4a59eafcb net: bridge: fix stale eth hdr pointer in br_dev_xmit
commit 823d81b0fa2cd83a640734e74caee338b5d3c093 upstream.

In br_dev_xmit() we perform vlan filtering in br_allowed_ingress() but
if the packet has the vlan header inside (e.g. bridge with disabled
tx-vlan-offload) then the vlan filtering code will use skb_vlan_untag()
to extract the vid before filtering which in turn calls pskb_may_pull()
and we may end up with a stale eth pointer. Moreover the cached eth header
pointer will generally be wrong after that operation. Remove the eth header
caching and just use eth_hdr() directly, the compiler does the right thing
and calculates it only once so we don't lose anything.

Fixes: 057658cb33fb ("bridge: suppress arp pkts on BR_NEIGH_SUPPRESS ports")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Eduardo Vela <Nava> <evn@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-16 12:52:50 +01:00
Florian Westphal
54b5ab456e netfilter: bridge: add support for pppoe filtering
[ Upstream commit 28b78ecffea8078d81466b2e01bb5a154509f1ba ]

This makes 'bridge-nf-filter-pppoe-tagged' sysctl work for
bridged traffic.

Looking at the original commit it doesn't appear this ever worked:

 static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
[..]
        if (skb->protocol == htons(ETH_P_8021Q)) {
                skb_pull(skb, VLAN_HLEN);
                skb->network_header += VLAN_HLEN;
+       } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
+               skb_pull(skb, PPPOE_SES_HLEN);
+               skb->network_header += PPPOE_SES_HLEN;
        }
 [..]
	NF_HOOK(... POST_ROUTING, ...)

... but the adjusted offsets are never restored.

The alternative would be to rip this code out for good,
but otoh we'd have to keep this anyway for the vlan handling
(which works because vlan tag info is in the skb, not the packet
 payload).

Reported-and-tested-by: Amish Chana <amish@3g.co.za>
Fixes: 516299d2f5b6f97 ("[NETFILTER]: bridge-nf: filter bridged IPv4/IPv6 encapsulated in pppoe traffic")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 09:19:31 +01:00
Eric Dumazet
c2c45102ae net: bridge: use nla_total_size_64bit() in br_get_linkxstats_size()
[ Upstream commit dbe0b88064494b7bb6a9b2aa7e085b14a3112d44 ]

bridge_fill_linkxstats() is using nla_reserve_64bit().

We must use nla_total_size_64bit() instead of nla_total_size()
for corresponding data structure.

Fixes: 1080ab95e3c7 ("net: bridge: add support for IGMP/MLD stats and export them via netlink")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Nikolay Aleksandrov <nikolay@nvidia.com>
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-10-13 10:08:19 +02:00
Yang Yingliang
33597972a2 net: bridge: fix memleak in br_add_if()
[ Upstream commit 519133debcc19f5c834e7e28480b60bdc234fe02 ]

I got a memleak report:

BUG: memory leak
unreferenced object 0x607ee521a658 (size 240):
comm "syz-executor.0", pid 955, jiffies 4294780569 (age 16.449s)
hex dump (first 32 bytes, cpu 1):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000d830ea5a>] br_multicast_add_port+0x1c2/0x300 net/bridge/br_multicast.c:1693
[<00000000274d9a71>] new_nbp net/bridge/br_if.c:435 [inline]
[<00000000274d9a71>] br_add_if+0x670/0x1740 net/bridge/br_if.c:611
[<0000000012ce888e>] do_set_master net/core/rtnetlink.c:2513 [inline]
[<0000000012ce888e>] do_set_master+0x1aa/0x210 net/core/rtnetlink.c:2487
[<0000000099d1cafc>] __rtnl_newlink+0x1095/0x13e0 net/core/rtnetlink.c:3457
[<00000000a01facc0>] rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3488
[<00000000acc9186c>] rtnetlink_rcv_msg+0x369/0xa10 net/core/rtnetlink.c:5550
[<00000000d4aabb9c>] netlink_rcv_skb+0x134/0x3d0 net/netlink/af_netlink.c:2504
[<00000000bc2e12a3>] netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
[<00000000bc2e12a3>] netlink_unicast+0x4a0/0x6a0 net/netlink/af_netlink.c:1340
[<00000000e4dc2d0e>] netlink_sendmsg+0x789/0xc70 net/netlink/af_netlink.c:1929
[<000000000d22c8b3>] sock_sendmsg_nosec net/socket.c:654 [inline]
[<000000000d22c8b3>] sock_sendmsg+0x139/0x170 net/socket.c:674
[<00000000e281417a>] ____sys_sendmsg+0x658/0x7d0 net/socket.c:2350
[<00000000237aa2ab>] ___sys_sendmsg+0xf8/0x170 net/socket.c:2404
[<000000004f2dc381>] __sys_sendmsg+0xd3/0x190 net/socket.c:2433
[<0000000005feca6c>] do_syscall_64+0x37/0x90 arch/x86/entry/common.c:47
[<000000007304477d>] entry_SYSCALL_64_after_hwframe+0x44/0xae

On error path of br_add_if(), p->mcast_stats allocated in
new_nbp() need be freed, or it will be leaked.

Fixes: 1080ab95e3c7 ("net: bridge: add support for IGMP/MLD stats and export them via netlink")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Link: https://lore.kernel.org/r/20210809132023.978546-1-yangyingliang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-18 08:57:00 +02:00
Yajun Deng
b036452082 netfilter: nf_conntrack_bridge: Fix memory leak when error
[ Upstream commit 38ea9def5b62f9193f6bad96c5d108e2830ecbde ]

It should be added kfree_skb_list() when err is not equal to zero
in nf_br_ip_fragment().

v2: keep this aligned with IPv6.
v3: modify iter.frag_list to iter.frag.

Fixes: 3c171f496ef5 ("netfilter: bridge: add connection tracking system")
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-18 08:56:58 +02:00
Wolfgang Bumiller
7ecd40801e net: bridge: sync fdb to new unicast-filtering ports
commit a019abd8022061b917da767cd1a66ed823724eab upstream.

Since commit 2796d0c648c9 ("bridge: Automatically manage
port promiscuous mode.")
bridges with `vlan_filtering 1` and only 1 auto-port don't
set IFF_PROMISC for unicast-filtering-capable ports.

Normally on port changes `br_manage_promisc` is called to
update the promisc flags and unicast filters if necessary,
but it cannot distinguish between *new* ports and ones
losing their promisc flag, and new ports end up not
receiving the MAC address list.

Fix this by calling `br_fdb_sync_static` in `br_add_if`
after the port promisc flags are updated and the unicast
filter was supposed to have been filled.

Fixes: 2796d0c648c9 ("bridge: Automatically manage port promiscuous mode.")
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-25 14:35:14 +02:00
Nikolay Aleksandrov
79855be644 net: bridge: fix vlan tunnel dst refcnt when egressing
commit cfc579f9d89af4ada58c69b03bcaa4887840f3b3 upstream.

The egress tunnel code uses dst_clone() and directly sets the result
which is wrong because the entry might have 0 refcnt or be already deleted,
causing number of problems. It also triggers the WARN_ON() in dst_hold()[1]
when a refcnt couldn't be taken. Fix it by using dst_hold_safe() and
checking if a reference was actually taken before setting the dst.

[1] dmesg WARN_ON log and following refcnt errors
 WARNING: CPU: 5 PID: 38 at include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]
 Modules linked in: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net
 CPU: 5 PID: 38 Comm: ksoftirqd/5 Kdump: loaded Tainted: G        W         5.13.0-rc3+ #360
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
 RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]
 Code: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 89 f6 e8 64 bc 01 e1 85 db 75 02 <0f> 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49
 RSP: 0018:ffff8881003d39e8 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0
 RBP: ffff8881040c6700 R08: 0000000000000000 R09: 0000000000000001
 R10: 2ce93d0054fe0d00 R11: 54fe0d00000e0000 R12: ffff888109515000
 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000401
 FS:  0000000000000000(0000) GS:ffff88822bf40000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0
 Call Trace:
  br_handle_vlan+0xbc/0xca [bridge]
  __br_forward+0x23/0x164 [bridge]
  deliver_clone+0x41/0x48 [bridge]
  br_handle_frame_finish+0x36f/0x3aa [bridge]
  ? skb_dst+0x2e/0x38 [bridge]
  ? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [bridge]
  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]
  br_handle_frame+0x2c3/0x377 [bridge]
  ? __skb_pull+0x33/0x51
  ? vlan_do_receive+0x4f/0x36a
  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]
  __netif_receive_skb_core+0x539/0x7c6
  ? __list_del_entry_valid+0x16e/0x1c2
  __netif_receive_skb_list_core+0x6d/0xd6
  netif_receive_skb_list_internal+0x1d9/0x1fa
  gro_normal_list+0x22/0x3e
  dev_gro_receive+0x55b/0x600
  ? detach_buf_split+0x58/0x140
  napi_gro_receive+0x94/0x12e
  virtnet_poll+0x15d/0x315 [virtio_net]
  __napi_poll+0x2c/0x1c9
  net_rx_action+0xe6/0x1fb
  __do_softirq+0x115/0x2d8
  run_ksoftirqd+0x18/0x20
  smpboot_thread_fn+0x183/0x19c
  ? smpboot_unregister_percpu_thread+0x66/0x66
  kthread+0x10a/0x10f
  ? kthread_mod_delayed_work+0xb6/0xb6
  ret_from_fork+0x22/0x30
 ---[ end trace 49f61b07f775fd2b ]---
 dst_release: dst:00000000c02d677a refcnt:-1
 dst_release underflow

Cc: stable@vger.kernel.org
Fixes: 11538d039ac6 ("bridge: vlan dst_metadata hooks in ingress and egress paths")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-23 14:41:30 +02:00
Nikolay Aleksandrov
a2241e62f6 net: bridge: fix vlan tunnel dst null pointer dereference
commit 58e2071742e38f29f051b709a5cca014ba51166f upstream.

This patch fixes a tunnel_dst null pointer dereference due to lockless
access in the tunnel egress path. When deleting a vlan tunnel the
tunnel_dst pointer is set to NULL without waiting a grace period (i.e.
while it's still usable) and packets egressing are dereferencing it
without checking. Use READ/WRITE_ONCE to annotate the lockless use of
tunnel_id, use RCU for accessing tunnel_dst and make sure it is read
only once and checked in the egress path. The dst is already properly RCU
protected so we don't need to do anything fancy than to make sure
tunnel_id and tunnel_dst are read only once and checked in the egress path.

Cc: stable@vger.kernel.org
Fixes: 11538d039ac6 ("bridge: vlan dst_metadata hooks in ingress and egress paths")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-23 14:41:30 +02:00
Zhang Zhengming
6cc777c6ac bridge: Fix possible races between assigning rx_handler_data and setting IFF_BRIDGE_PORT bit
[ Upstream commit 59259ff7a81b9eb6213891c6451221e567f8f22f ]

There is a crash in the function br_get_link_af_size_filtered,
as the port_exists(dev) is true and the rx_handler_data of dev is NULL.
But the rx_handler_data of dev is correct saved in vmcore.

The oops looks something like:
 ...
 pc : br_get_link_af_size_filtered+0x28/0x1c8 [bridge]
 ...
 Call trace:
  br_get_link_af_size_filtered+0x28/0x1c8 [bridge]
  if_nlmsg_size+0x180/0x1b0
  rtnl_calcit.isra.12+0xf8/0x148
  rtnetlink_rcv_msg+0x334/0x370
  netlink_rcv_skb+0x64/0x130
  rtnetlink_rcv+0x28/0x38
  netlink_unicast+0x1f0/0x250
  netlink_sendmsg+0x310/0x378
  sock_sendmsg+0x4c/0x70
  __sys_sendto+0x120/0x150
  __arm64_sys_sendto+0x30/0x40
  el0_svc_common+0x78/0x130
  el0_svc_handler+0x38/0x78
  el0_svc+0x8/0xc

In br_add_if(), we found there is no guarantee that
assigning rx_handler_data to dev->rx_handler_data
will before setting the IFF_BRIDGE_PORT bit of priv_flags.
So there is a possible data competition:

CPU 0:                                                        CPU 1:
(RCU read lock)                                               (RTNL lock)
rtnl_calcit()                                                 br_add_slave()
  if_nlmsg_size()                                               br_add_if()
    br_get_link_af_size_filtered()                              -> netdev_rx_handler_register
                                                                    ...
                                                                    // The order is not guaranteed
      ...                                                           -> dev->priv_flags |= IFF_BRIDGE_PORT;
      // The IFF_BRIDGE_PORT bit of priv_flags has been set
      -> if (br_port_exists(dev)) {
        // The dev->rx_handler_data has NOT been assigned
        -> p = br_port_get_rcu(dev);
        ....
                                                                    -> rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
                                                                     ...

Fix it in br_get_link_af_size_filtered, using br_port_get_check_rcu() and checking the return value.

Signed-off-by: Zhang Zhengming <zhangzhengming@huawei.com>
Reviewed-by: Zhao Lei <zhaolei69@huawei.com>
Reviewed-by: Wang Xiaogang <wangxiaogang3@huawei.com>
Suggested-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-22 11:38:29 +02:00
Nikolay Aleksandrov
29e498ff18 net: bridge: when suppression is enabled exclude RARP packets
[ Upstream commit 0353b4a96b7a9f60fe20d1b3ebd4931a4085f91c ]

Recently we had an interop issue where RARP packets got suppressed with
bridge neigh suppression enabled, but the check in the code was meant to
suppress GARP. Exclude RARP packets from it which would allow some VMWare
setups to work, to quote the report:
"Those RARP packets usually get generated by vMware to notify physical
switches when vMotion occurs. vMware may use random sip/tip or just use
sip=tip=0. So the RARP packet sometimes get properly flooded by the vtep
and other times get dropped by the logic"

Reported-by: Amer Abdalamer <amer@nvidia.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:08:21 +02:00
Linus Lüssing
07ef3f7bc5 net: bridge: mcast: fix broken length + header check for MRDv6 Adv.
[ Upstream commit 99014088156cd78867d19514a0bc771c4b86b93b ]

The IPv6 Multicast Router Advertisements parsing has the following two
issues:

For one thing, ICMPv6 MRD Advertisements are smaller than ICMPv6 MLD
messages (ICMPv6 MRD Adv.: 8 bytes vs. ICMPv6 MLDv1/2: >= 24 bytes,
assuming MLDv2 Reports with at least one multicast address entry).
When ipv6_mc_check_mld_msg() tries to parse an Multicast Router
Advertisement its MLD length check will fail - and it will wrongly
return -EINVAL, even if we have a valid MRD Advertisement. With the
returned -EINVAL the bridge code will assume a broken packet and will
wrongly discard it, potentially leading to multicast packet loss towards
multicast routers.

The second issue is the MRD header parsing in
br_ip6_multicast_mrd_rcv(): It wrongly checks for an ICMPv6 header
immediately after the IPv6 header (IPv6 next header type). However
according to RFC4286, section 2 all MRD messages contain a Router Alert
option (just like MLD). So instead there is an IPv6 Hop-by-Hop option
for the Router Alert between the IPv6 and ICMPv6 header, again leading
to the bridge wrongly discarding Multicast Router Advertisements.

To fix these two issues, introduce a new return value -ENODATA to
ipv6_mc_check_mld() to indicate a valid ICMPv6 packet with a hop-by-hop
option which is not an MLD but potentially an MRD packet. This also
simplifies further parsing in the bridge code, as ipv6_mc_check_mld()
already fully checks the ICMPv6 header and hop-by-hop option.

These issues were found and fixed with the help of the mrdisc tool
(https://github.com/troglobit/mrdisc).

Fixes: 4b3087c7e37f ("bridge: Snoop Multicast Router Advertisements")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:44:32 +02:00
Florian Westphal
ce23be37ec netfilter: bridge: add pre_exit hooks for ebtable unregistration
commit 7ee3c61dcd28bf6e290e06ad382f13511dc790e9 upstream.

Just like ip/ip6/arptables, the hooks have to be removed, then
synchronize_rcu() has to be called to make sure no more packets are being
processed before the ruleset data is released.

Place the hook unregistration in the pre_exit hook, then call the new
ebtables pre_exit function from there.

Years ago, when first netns support got added for netfilter+ebtables,
this used an older (now removed) netfilter hook unregister API, that did
a unconditional synchronize_rcu().

Now that all is done with call_rcu, ebtable_{filter,nat,broute} pernet exit
handlers may free the ebtable ruleset while packets are still in flight.

This can only happens on module removal, not during netns exit.

The new function expects the table name, not the table struct.

This is because upcoming patch set (targeting -next) will remove all
net->xt.{nat,filter,broute}_table instances, this makes it necessary
to avoid external references to those member variables.

The existing APIs will be converted, so follow the upcoming scheme of
passing name + hook type instead.

Fixes: aee12a0a3727e ("ebtables: remove nf_hook_register usage")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-21 12:56:16 +02:00
Vladimir Oltean
ad112654e2 net: bridge: use switchdev for port flags set through sysfs too
commit 8043c845b63a2dd88daf2d2d268a33e1872800f0 upstream.

Looking through patchwork I don't see that there was any consensus to
use switchdev notifiers only in case of netlink provided port flags but
not sysfs (as a sort of deprecation, punishment or anything like that),
so we should probably keep the user interface consistent in terms of
functionality.

http://patchwork.ozlabs.org/project/netdev/patch/20170605092043.3523-3-jiri@resnulli.us/
http://patchwork.ozlabs.org/project/netdev/patch/20170608064428.4785-3-jiri@resnulli.us/

Fixes: 3922285d96e7 ("net: bridge: Add support for offloading port attributes")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07 12:20:43 +01:00
Wang Hai
49de0a17e6 net: bridge: Fix a warning when del bridge sysfs
[ Upstream commit 989a1db06eb18ff605377eec87e18d795e0ec74b ]

I got a warining report:

br_sysfs_addbr: can't create group bridge4/bridge
------------[ cut here ]------------
sysfs group 'bridge' not found for kobject 'bridge4'
WARNING: CPU: 2 PID: 9004 at fs/sysfs/group.c:279 sysfs_remove_group fs/sysfs/group.c:279 [inline]
WARNING: CPU: 2 PID: 9004 at fs/sysfs/group.c:279 sysfs_remove_group+0x153/0x1b0 fs/sysfs/group.c:270
Modules linked in: iptable_nat
...
Call Trace:
  br_dev_delete+0x112/0x190 net/bridge/br_if.c:384
  br_dev_newlink net/bridge/br_netlink.c:1381 [inline]
  br_dev_newlink+0xdb/0x100 net/bridge/br_netlink.c:1362
  __rtnl_newlink+0xe11/0x13f0 net/core/rtnetlink.c:3441
  rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3500
  rtnetlink_rcv_msg+0x385/0x980 net/core/rtnetlink.c:5562
  netlink_rcv_skb+0x134/0x3d0 net/netlink/af_netlink.c:2494
  netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
  netlink_unicast+0x4a0/0x6a0 net/netlink/af_netlink.c:1330
  netlink_sendmsg+0x793/0xc80 net/netlink/af_netlink.c:1919
  sock_sendmsg_nosec net/socket.c:651 [inline]
  sock_sendmsg+0x139/0x170 net/socket.c:671
  ____sys_sendmsg+0x658/0x7d0 net/socket.c:2353
  ___sys_sendmsg+0xf8/0x170 net/socket.c:2407
  __sys_sendmsg+0xd3/0x190 net/socket.c:2440
  do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

In br_device_event(), if the bridge sysfs fails to be added,
br_device_event() should return error. This can prevent warining
when removing bridge sysfs that do not exist.

Fixes: bb900b27a2f4 ("bridge: allow creating bridge devices with netlink")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Tested-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Link: https://lore.kernel.org/r/20201211122921.40386-1-wanghai38@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-23 15:02:25 +01:00
Joseph Huang
d8d39e1366 bridge: Fix a deadlock when enabling multicast snooping
[ Upstream commit 851d0a73c90e6c8c63fef106c6c1e73df7e05d9d ]

When enabling multicast snooping, bridge module deadlocks on multicast_lock
if 1) IPv6 is enabled, and 2) there is an existing querier on the same L2
network.

The deadlock was caused by the following sequence: While holding the lock,
br_multicast_open calls br_multicast_join_snoopers, which eventually causes
IP stack to (attempt to) send out a Listener Report (in igmp6_join_group).
Since the destination Ethernet address is a multicast address, br_dev_xmit
feeds the packet back to the bridge via br_multicast_rcv, which in turn
calls br_multicast_add_group, which then deadlocks on multicast_lock.

The fix is to move the call br_multicast_join_snoopers outside of the
critical section. This works since br_multicast_join_snoopers only deals
with IP and does not modify any multicast data structures of the bridge,
so there's no need to hold the lock.

Steps to reproduce:
1. sysctl net.ipv6.conf.all.force_mld_version=1
2. have another querier
3. ip link set dev bridge type bridge mcast_snooping 0 && \
   ip link set dev bridge type bridge mcast_snooping 1 < deadlock >

A typical call trace looks like the following:

[  936.251495]  _raw_spin_lock+0x5c/0x68
[  936.255221]  br_multicast_add_group+0x40/0x170 [bridge]
[  936.260491]  br_multicast_rcv+0x7ac/0xe30 [bridge]
[  936.265322]  br_dev_xmit+0x140/0x368 [bridge]
[  936.269689]  dev_hard_start_xmit+0x94/0x158
[  936.273876]  __dev_queue_xmit+0x5ac/0x7f8
[  936.277890]  dev_queue_xmit+0x10/0x18
[  936.281563]  neigh_resolve_output+0xec/0x198
[  936.285845]  ip6_finish_output2+0x240/0x710
[  936.290039]  __ip6_finish_output+0x130/0x170
[  936.294318]  ip6_output+0x6c/0x1c8
[  936.297731]  NF_HOOK.constprop.0+0xd8/0xe8
[  936.301834]  igmp6_send+0x358/0x558
[  936.305326]  igmp6_join_group.part.0+0x30/0xf0
[  936.309774]  igmp6_group_added+0xfc/0x110
[  936.313787]  __ipv6_dev_mc_inc+0x1a4/0x290
[  936.317885]  ipv6_dev_mc_inc+0x10/0x18
[  936.321677]  br_multicast_open+0xbc/0x110 [bridge]
[  936.326506]  br_multicast_toggle+0xec/0x140 [bridge]

Fixes: 4effd28c1245 ("bridge: join all-snoopers multicast address")
Signed-off-by: Joseph Huang <Joseph.Huang@garmin.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Link: https://lore.kernel.org/r/20201204235628.50653-1-Joseph.Huang@garmin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-21 13:27:04 +01:00
Zhang Changzhong
cae90bd22c net: bridge: vlan: fix error return code in __vlan_add()
[ Upstream commit ee4f52a8de2c6f78b01f10b4c330867d88c1653a ]

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: f8ed289fab84 ("bridge: vlan: use br_vlan_(get|put)_master to deal with refcounts")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Link: https://lore.kernel.org/r/1607071737-33875-1-git-send-email-zhangchangzhong@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-21 13:27:03 +01:00
Antoine Tenart
4615228a50 netfilter: bridge: reset skb->pkt_type after NF_INET_POST_ROUTING traversal
[ Upstream commit 44f64f23bae2f0fad25503bc7ab86cd08d04cd47 ]

Netfilter changes PACKET_OTHERHOST to PACKET_HOST before invoking the
hooks as, while it's an expected value for a bridge, routing expects
PACKET_HOST. The change is undone later on after hook traversal. This
can be seen with pairs of functions updating skb>pkt_type and then
reverting it to its original value:

For hook NF_INET_PRE_ROUTING:
  setup_pre_routing / br_nf_pre_routing_finish

For hook NF_INET_FORWARD:
  br_nf_forward_ip / br_nf_forward_finish

But the third case where netfilter does this, for hook
NF_INET_POST_ROUTING, the packet type is changed in br_nf_post_routing
but never reverted. A comment says:

  /* We assume any code from br_dev_queue_push_xmit onwards doesn't care
   * about the value of skb->pkt_type. */

But when having a tunnel (say vxlan) attached to a bridge we have the
following call trace:

  br_nf_pre_routing
  br_nf_pre_routing_ipv6
     br_nf_pre_routing_finish
  br_nf_forward_ip
     br_nf_forward_finish
  br_nf_post_routing           <- pkt_type is updated to PACKET_HOST
     br_nf_dev_queue_xmit      <- but not reverted to its original value
  vxlan_xmit
     vxlan_xmit_one
        skb_tunnel_check_pmtu  <- a check on pkt_type is performed

In this specific case, this creates issues such as when an ICMPv6 PTB
should be sent back. When CONFIG_BRIDGE_NETFILTER is enabled, the PTB
isn't sent (as skb_tunnel_check_pmtu checks if pkt_type is PACKET_HOST
and returns early).

If the comment is right and no one cares about the value of
skb->pkt_type after br_dev_queue_push_xmit (which isn't true), resetting
it to its original value should be safe.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20201123174902.622102-1-atenart@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-08 10:40:24 +01:00
Heiner Kallweit
805dfdb26e net: bridge: add missing counters to ndo_get_stats64 callback
[ Upstream commit 7a30ecc9237681bb125cbd30eee92bef7e86293d ]

In br_forward.c and br_input.c fields dev->stats.tx_dropped and
dev->stats.multicast are populated, but they are ignored in
ndo_get_stats64.

Fixes: 28172739f0a2 ("net: fix 64 bit counters on 32 bit arches")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/58ea9963-77ad-a7cf-8dfd-fc95ab95f606@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-24 13:28:57 +01:00
Timothée COCAULT
2f3839075a netfilter: ebtables: Fixes dropping of small packets in bridge nat
[ Upstream commit 63137bc5882a1882c553d389fdeeeace86ee1741 ]

Fixes an error causing small packets to get dropped. skb_ensure_writable
expects the second parameter to be a length in the ethernet payload.=20
If we want to write the ethernet header (src, dst), we should pass 0.
Otherwise, packets with small payloads (< ETH_ALEN) will get dropped.

Fixes: c1a831167901 ("netfilter: bridge: convert skb_make_writable to skb_ensure_writable")
Signed-off-by: Timothée COCAULT <timothee.cocault@orange.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29 09:57:57 +01:00
Vladimir Oltean
450c0c00a5 net: bridge: br_vlan_get_pvid_rcu() should dereference the VLAN group under RCU
[ Upstream commit 99f62a746066fa436aa15d4606a538569540db08 ]

When calling the RCU brother of br_vlan_get_pvid(), lockdep warns:

=============================
WARNING: suspicious RCU usage
5.9.0-rc3-01631-g13c17acb8e38-dirty #814 Not tainted
-----------------------------
net/bridge/br_private.h:1054 suspicious rcu_dereference_protected() usage!

Call trace:
 lockdep_rcu_suspicious+0xd4/0xf8
 __br_vlan_get_pvid+0xc0/0x100
 br_vlan_get_pvid_rcu+0x78/0x108

The warning is because br_vlan_get_pvid_rcu() calls nbp_vlan_group()
which calls rtnl_dereference() instead of rcu_dereference(). In turn,
rtnl_dereference() calls rcu_dereference_protected() which assumes
operation under an RCU write-side critical section, which obviously is
not the case here. So, when the incorrect primitive is used to access
the RCU-protected VLAN group pointer, READ_ONCE() is not used, which may
cause various unexpected problems.

I'm sad to say that br_vlan_get_pvid() and br_vlan_get_pvid_rcu() cannot
share the same implementation. So fix the bug by splitting the 2
functions, and making br_vlan_get_pvid_rcu() retrieve the VLAN groups
under proper locking annotations.

Fixes: 7582f5b70f9a ("bridge: add br_vlan_get_pvid_rcu()")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-26 18:03:12 +02:00
Florian Westphal
3803312a3c netfilter: avoid ipv6 -> nf_defrag_ipv6 module dependency
[ Upstream commit 2404b73c3f1a5f15726c6ecd226b56f6f992767f ]

nf_ct_frag6_gather is part of nf_defrag_ipv6.ko, not ipv6 core.

The current use of the netfilter ipv6 stub indirections  causes a module
dependency between ipv6 and nf_defrag_ipv6.

This prevents nf_defrag_ipv6 module from being removed because ipv6 can't
be unloaded.

Remove the indirection and always use a direct call.  This creates a
depency from nf_conntrack_bridge to nf_defrag_ipv6 instead:

modinfo nf_conntrack
depends:        nf_conntrack,nf_defrag_ipv6,bridge

.. and nf_conntrack already depends on nf_defrag_ipv6 anyway.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-03 11:26:58 +02:00
Linus Lüssing
aef7a9e21a bridge: mcast: Fix MLD2 Report IPv6 payload length check
[ Upstream commit 5fc6266af7b427243da24f3443a50cd4584aac06 ]

Commit e57f61858b7c ("net: bridge: mcast: fix stale nsrcs pointer in
igmp3/mld2 report handling") introduced a bug in the IPv6 header payload
length check which would potentially lead to rejecting a valid MLD2 Report:

The check needs to take into account the 2 bytes for the "Number of
Sources" field in the "Multicast Address Record" before reading it.
And not the size of a pointer to this field.

Fixes: e57f61858b7c ("net: bridge: mcast: fix stale nsrcs pointer in igmp3/mld2 report handling")
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-22 09:32:46 +02:00
Thomas Martitz
f32325b100 net: bridge: enfore alignment for ethernet address
[ Upstream commit db7202dec92e6caa2706c21d6fc359af318bde2e ]

The eth_addr member is passed to ether_addr functions that require
2-byte alignment, therefore the member must be properly aligned
to avoid unaligned accesses.

The problem is in place since the initial merge of multicast to unicast:
commit 6db6f0eae6052b70885562e1733896647ec1d807 bridge: multicast to unicast

Fixes: 6db6f0eae605 ("bridge: multicast to unicast")
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Felix Fietkau <nbd@nbd.name>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Martitz <t.martitz@avm.de>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:36:44 -04:00
Ido Schimmel
de9d1010b9 bridge: Avoid infinite loop when suppressing NS messages with invalid options
[ Upstream commit 53fc685243bd6fb90d90305cea54598b78d3cbfc ]

When neighbor suppression is enabled the bridge device might reply to
Neighbor Solicitation (NS) messages on behalf of remote hosts.

In case the NS message includes the "Source link-layer address" option
[1], the bridge device will use the specified address as the link-layer
destination address in its reply.

To avoid an infinite loop, break out of the options parsing loop when
encountering an option with length zero and disregard the NS message.

This is consistent with the IPv6 ndisc code and RFC 4886 which states
that "Nodes MUST silently discard an ND packet that contains an option
with length zero" [2].

[1] https://tools.ietf.org/html/rfc4861#section-4.3
[2] https://tools.ietf.org/html/rfc4861#section-4.6

Fixes: ed842faeb2bd ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Alla Segal <allas@mellanox.com>
Tested-by: Alla Segal <allas@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-17 16:40:20 +02:00
Michael Braun
25f629a706 netfilter: nft_reject_bridge: enable reject with bridge vlan
commit e9c284ec4b41c827f4369973d2792992849e4fa5 upstream.

Currently, using the bridge reject target with tagged packets
results in untagged packets being sent back.

Fix this by mirroring the vlan id as well.

Fixes: 85f5b3086a04 ("netfilter: bridge: add reject support")
Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:21:34 +02:00
Hangbin Liu
d49ce85cad net: add bool confirm_neigh parameter for dst_ops.update_pmtu
[ Upstream commit bd085ef678b2cc8c38c105673dfe8ff8f5ec0c57 ]

The MTU update code is supposed to be invoked in response to real
networking events that update the PMTU. In IPv6 PMTU update function
__ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor
confirmed time.

But for tunnel code, it will call pmtu before xmit, like:
  - tnl_update_pmtu()
    - skb_dst_update_pmtu()
      - ip6_rt_update_pmtu()
        - __ip6_rt_update_pmtu()
          - dst_confirm_neigh()

If the tunnel remote dst mac address changed and we still do the neigh
confirm, we will not be able to update neigh cache and ping6 remote
will failed.

So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we
should not be invoking dst_confirm_neigh() as we have no evidence
of successful two-way communication at this point.

On the other hand it is also important to keep the neigh reachability fresh
for TCP flows, so we cannot remove this dst_confirm_neigh() call.

To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu
to choose whether we should do neigh update or not. I will add the parameter
in this patch and set all the callers to true to comply with the previous
way, and fix the tunnel code one by one on later patches.

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Suggested-by: David Miller <davem@davemloft.net>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04 19:18:58 +01:00
Eric Dumazet
b0fc9cf57f netfilter: bridge: make sure to pull arp header in br_nf_forward_arp()
commit 5604285839aaedfb23ebe297799c6e558939334d upstream.

syzbot is kind enough to remind us we need to call skb_may_pull()

BUG: KMSAN: uninit-value in br_nf_forward_arp+0xe61/0x1230 net/bridge/br_netfilter_hooks.c:665
CPU: 1 PID: 11631 Comm: syz-executor.1 Not tainted 5.4.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108
 __msan_warning+0x64/0xc0 mm/kmsan/kmsan_instr.c:245
 br_nf_forward_arp+0xe61/0x1230 net/bridge/br_netfilter_hooks.c:665
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x18b/0x3f0 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 __br_forward+0x78f/0xe30 net/bridge/br_forward.c:109
 br_flood+0xef0/0xfe0 net/bridge/br_forward.c:234
 br_handle_frame_finish+0x1a77/0x1c20 net/bridge/br_input.c:162
 nf_hook_bridge_pre net/bridge/br_input.c:245 [inline]
 br_handle_frame+0xfb6/0x1eb0 net/bridge/br_input.c:348
 __netif_receive_skb_core+0x20b9/0x51a0 net/core/dev.c:4830
 __netif_receive_skb_one_core net/core/dev.c:4927 [inline]
 __netif_receive_skb net/core/dev.c:5043 [inline]
 process_backlog+0x610/0x13c0 net/core/dev.c:5874
 napi_poll net/core/dev.c:6311 [inline]
 net_rx_action+0x7a6/0x1aa0 net/core/dev.c:6379
 __do_softirq+0x4a1/0x83a kernel/softirq.c:293
 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1091
 </IRQ>
 do_softirq kernel/softirq.c:338 [inline]
 __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 rcu_read_unlock_bh include/linux/rcupdate.h:688 [inline]
 __dev_queue_xmit+0x38e8/0x4200 net/core/dev.c:3819
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3825
 packet_snd net/packet/af_packet.c:2959 [inline]
 packet_sendmsg+0x8234/0x9100 net/packet/af_packet.c:2984
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 __sys_sendto+0xc44/0xc70 net/socket.c:1952
 __do_sys_sendto net/socket.c:1964 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1960
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1960
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45a679
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f0a3c9e5c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045a679
RDX: 000000000000000e RSI: 0000000020000200 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 00000000200000c0 R09: 0000000000000014
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0a3c9e66d4
R13: 00000000004c8ec1 R14: 00000000004dfe28 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:149 [inline]
 kmsan_internal_poison_shadow+0x5c/0x110 mm/kmsan/kmsan.c:132
 kmsan_slab_alloc+0x97/0x100 mm/kmsan/kmsan_hooks.c:86
 slab_alloc_node mm/slub.c:2773 [inline]
 __kmalloc_node_track_caller+0xe27/0x11a0 mm/slub.c:4381
 __kmalloc_reserve net/core/skbuff.c:141 [inline]
 __alloc_skb+0x306/0xa10 net/core/skbuff.c:209
 alloc_skb include/linux/skbuff.h:1049 [inline]
 alloc_skb_with_frags+0x18c/0xa80 net/core/skbuff.c:5662
 sock_alloc_send_pskb+0xafd/0x10a0 net/core/sock.c:2244
 packet_alloc_skb net/packet/af_packet.c:2807 [inline]
 packet_snd net/packet/af_packet.c:2902 [inline]
 packet_sendmsg+0x63a6/0x9100 net/packet/af_packet.c:2984
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 __sys_sendto+0xc44/0xc70 net/socket.c:1952
 __do_sys_sendto net/socket.c:1964 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1960
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1960
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: c4e70a87d975 ("netfilter: bridge: rename br_netfilter.c to br_netfilter_hooks.c")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04 19:18:38 +01:00
Florian Westphal
b54ba0dc0d netfilter: ebtables: compat: reject all padding in matches/watchers
commit e608f631f0ba5f1fc5ee2e260a3a35d13107cbfe upstream.

syzbot reported following splat:

BUG: KASAN: vmalloc-out-of-bounds in size_entry_mwt net/bridge/netfilter/ebtables.c:2063 [inline]
BUG: KASAN: vmalloc-out-of-bounds in compat_copy_entries+0x128b/0x1380 net/bridge/netfilter/ebtables.c:2155
Read of size 4 at addr ffffc900004461f4 by task syz-executor267/7937

CPU: 1 PID: 7937 Comm: syz-executor267 Not tainted 5.5.0-rc1-syzkaller #0
 size_entry_mwt net/bridge/netfilter/ebtables.c:2063 [inline]
 compat_copy_entries+0x128b/0x1380 net/bridge/netfilter/ebtables.c:2155
 compat_do_replace+0x344/0x720 net/bridge/netfilter/ebtables.c:2249
 compat_do_ebt_set_ctl+0x22f/0x27e net/bridge/netfilter/ebtables.c:2333
 [..]

Because padding isn't considered during computation of ->buf_user_offset,
"total" is decremented by fewer bytes than it should.

Therefore, the first part of

if (*total < sizeof(*entry) || entry->next_offset < sizeof(*entry))

will pass, -- it should not have.  This causes oob access:
entry->next_offset is past the vmalloced size.

Reject padding and check that computed user offset (sum of ebt_entry
structure plus all individual matches/watchers/targets) is same
value that userspace gave us as the offset of the next entry.

Reported-by: syzbot+f68108fed972453a0ad4@syzkaller.appspotmail.com
Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04 19:18:36 +01:00
Nikolay Aleksandrov
c1780f088f net: bridge: deny dev_set_mac_address() when unregistering
[ Upstream commit c4b4c421857dc7b1cf0dccbd738472360ff2cd70 ]

We have an interesting memory leak in the bridge when it is being
unregistered and is a slave to a master device which would change the
mac of its slaves on unregister (e.g. bond, team). This is a very
unusual setup but we do end up leaking 1 fdb entry because
dev_set_mac_address() would cause the bridge to insert the new mac address
into its table after all fdbs are flushed, i.e. after dellink() on the
bridge has finished and we call NETDEV_UNREGISTER the bond/team would
release it and will call dev_set_mac_address() to restore its original
address and that in turn will add an fdb in the bridge.
One fix is to check for the bridge dev's reg_state in its
ndo_set_mac_address callback and return an error if the bridge is not in
NETREG_REGISTERED.

Easy steps to reproduce:
 1. add bond in mode != A/B
 2. add any slave to the bond
 3. add bridge dev as a slave to the bond
 4. destroy the bridge device

Trace:
 unreferenced object 0xffff888035c4d080 (size 128):
   comm "ip", pid 4068, jiffies 4296209429 (age 1413.753s)
   hex dump (first 32 bytes):
     41 1d c9 36 80 88 ff ff 00 00 00 00 00 00 00 00  A..6............
     d2 19 c9 5e 3f d7 00 00 00 00 00 00 00 00 00 00  ...^?...........
   backtrace:
     [<00000000ddb525dc>] kmem_cache_alloc+0x155/0x26f
     [<00000000633ff1e0>] fdb_create+0x21/0x486 [bridge]
     [<0000000092b17e9c>] fdb_insert+0x91/0xdc [bridge]
     [<00000000f2a0f0ff>] br_fdb_change_mac_address+0xb3/0x175 [bridge]
     [<000000001de02dbd>] br_stp_change_bridge_id+0xf/0xff [bridge]
     [<00000000ac0e32b1>] br_set_mac_address+0x76/0x99 [bridge]
     [<000000006846a77f>] dev_set_mac_address+0x63/0x9b
     [<00000000d30738fc>] __bond_release_one+0x3f6/0x455 [bonding]
     [<00000000fc7ec01d>] bond_netdev_event+0x2f2/0x400 [bonding]
     [<00000000305d7795>] notifier_call_chain+0x38/0x56
     [<0000000028885d4a>] call_netdevice_notifiers+0x1e/0x23
     [<000000008279477b>] rollback_registered_many+0x353/0x6a4
     [<0000000018ef753a>] unregister_netdevice_many+0x17/0x6f
     [<00000000ba854b7a>] rtnl_delete_link+0x3c/0x43
     [<00000000adf8618d>] rtnl_dellink+0x1dc/0x20a
     [<000000009b6395fd>] rtnetlink_rcv_msg+0x23d/0x268

Fixes: 43598813386f ("bridge: add local MAC address to forwarding table (v2)")
Reported-by: syzbot+2add91c08eb181fea1bf@syzkaller.appspotmail.com
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-18 16:08:19 +01:00
Florian Westphal
b23c0742c2 bridge: ebtables: don't crash when using dnat target in output chains
xt_in() returns NULL in the output hook, skip the pkt_type change for
that case, redirection only makes sense in broute/prerouting hooks.

Reported-by: Tom Yan <tom.ty89@gmail.com>
Cc: Linus Lüssing <linus.luessing@c0d3.blue>
Fixes: cf3cb246e277d ("bridge: ebtables: fix reception of frames DNAT-ed to bridge device/port")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-11-04 20:58:34 +01:00
Taehee Yoo
ab92d68fc2 net: core: add generic lockdep keys
Some interface types could be nested.
(VLAN, BONDING, TEAM, MACSEC, MACVLAN, IPVLAN, VIRT_WIFI, VXLAN, etc..)
These interface types should set lockdep class because, without lockdep
class key, lockdep always warn about unexisting circular locking.

In the current code, these interfaces have their own lockdep class keys and
these manage itself. So that there are so many duplicate code around the
/driver/net and /net/.
This patch adds new generic lockdep keys and some helper functions for it.

This patch does below changes.
a) Add lockdep class keys in struct net_device
   - qdisc_running, xmit, addr_list, qdisc_busylock
   - these keys are used as dynamic lockdep key.
b) When net_device is being allocated, lockdep keys are registered.
   - alloc_netdev_mqs()
c) When net_device is being free'd llockdep keys are unregistered.
   - free_netdev()
d) Add generic lockdep key helper function
   - netdev_register_lockdep_key()
   - netdev_unregister_lockdep_key()
   - netdev_update_lockdep_key()
e) Remove unnecessary generic lockdep macro and functions
f) Remove unnecessary lockdep code of each interfaces.

After this patch, each interface modules don't need to maintain
their lockdep keys.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-24 14:53:48 -07:00
Eric Dumazet
e7a409c3f4 ipv4: fix IPSKB_FRAG_PMTU handling with fragmentation
This patch removes the iph field from the state structure, which is not
properly initialized. Instead, add a new field to make the "do we want
to set DF" be the state bit and move the code to set the DF flag from
ip_frag_next().

Joint work with Pablo and Linus.

Fixes: 19c3401a917b ("net: ipv4: place control buffer handling away from fragmentation iterators")
Reported-by: Patrick Schönthaler <patrick@notvads.ovh>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-21 10:46:42 -07:00
Eric Dumazet
9669fffc14 net: ensure correct skb->tstamp in various fragmenters
Thomas found that some forwarded packets would be stuck
in FQ packet scheduler because their skb->tstamp contained
timestamps far in the future.

We thought we addressed this point in commit 8203e2d844d3
("net: clear skb->tstamp in forwarding paths") but there
is still an issue when/if a packet needs to be fragmented.

In order to meet EDT requirements, we have to make sure all
fragments get the original skb->tstamp.

Note that this original skb->tstamp should be zero in
forwarding path, but might have a non zero value in
output path if user decided so.

Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Thomas Bartschies <Thomas.Bartschies@cvk.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-18 10:02:37 -07:00
David S. Miller
aa2eaa8c27 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor overlapping changes in the btusb and ixgbe drivers.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 14:17:27 +02:00
Jeremy Sowden
46705b070c netfilter: move nf_bridge_frag_data struct definition to a more appropriate header.
There is a struct definition function in nf_conntrack_bridge.h which is
not specific to conntrack and is used elswhere in netfilter.  Move it
into netfilter_bridge.h.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-09-13 12:35:33 +02:00