When we are allocating an array, using kmemdup_array() to take care about
multiplication and possible overflows.
Also it makes auditing the code easier.
Signed-off-by: Yan Zhen <yanzhen@vivo.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
mono_delivery_time was added to check if skb->tstamp has delivery
time in mono clock base (i.e. EDT) otherwise skb->tstamp has
timestamp in ingress and delivery_time at egress.
Renaming the bitfield from mono_delivery_time to tstamp_type is for
extensibilty for other timestamps such as userspace timestamp
(i.e. SO_TXTIME) set via sock opts.
As we are renaming the mono_delivery_time to tstamp_type, it makes
sense to start assigning tstamp_type based on enum defined
in this commit.
Earlier we used bool arg flag to check if the tstamp is mono in
function skb_set_delivery_time, Now the signature of the functions
accepts tstamp_type to distinguish between mono and real time.
Also skb_set_delivery_type_by_clockid is a new function which accepts
clockid to determine the tstamp_type.
In future tstamp_type:1 can be extended to support userspace timestamp
by increasing the bitfield.
Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240509211834.3235191-2-quic_abchauha@quicinc.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
conntrack nf_confirm logic cannot handle cloned skbs referencing
the same nf_conn entry, which will happen for multicast (broadcast)
frames on bridges.
Example:
macvlan0
|
br0
/ \
ethX ethY
ethX (or Y) receives a L2 multicast or broadcast packet containing
an IP packet, flow is not yet in conntrack table.
1. skb passes through bridge and fake-ip (br_netfilter)Prerouting.
-> skb->_nfct now references a unconfirmed entry
2. skb is broad/mcast packet. bridge now passes clones out on each bridge
interface.
3. skb gets passed up the stack.
4. In macvlan case, macvlan driver retains clone(s) of the mcast skb
and schedules a work queue to send them out on the lower devices.
The clone skb->_nfct is not a copy, it is the same entry as the
original skb. The macvlan rx handler then returns RX_HANDLER_PASS.
5. Normal conntrack hooks (in NF_INET_LOCAL_IN) confirm the orig skb.
The Macvlan broadcast worker and normal confirm path will race.
This race will not happen if step 2 already confirmed a clone. In that
case later steps perform skb_clone() with skb->_nfct already confirmed (in
hash table). This works fine.
But such confirmation won't happen when eb/ip/nftables rules dropped the
packets before they reached the nf_confirm step in postrouting.
Pablo points out that nf_conntrack_bridge doesn't allow use of stateful
nat, so we can safely discard the nf_conn entry and let inet call
conntrack again.
This doesn't work for bridge netfilter: skb could have a nat
transformation. Also bridge nf prevents re-invocation of inet prerouting
via 'sabotage_in' hook.
Work around this problem by explicit confirmation of the entry at LOCAL_IN
time, before upper layer has a chance to clone the unconfirmed entry.
The downside is that this disables NAT and conntrack helpers.
Alternative fix would be to add locking to all code parts that deal with
unconfirmed packets, but even if that could be done in a sane way this
opens up other problems, for example:
-m physdev --physdev-out eth0 -j SNAT --snat-to 1.2.3.4
-m physdev --physdev-out eth1 -j SNAT --snat-to 1.2.3.5
For multicast case, only one of such conflicting mappings will be
created, conntrack only handles 1:1 NAT mappings.
Users should set create a setup that explicitly marks such traffic
NOTRACK (conntrack bypass) to avoid this, but we cannot auto-bypass
them, ruleset might have accept rules for untracked traffic already,
so user-visible behaviour would change.
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217777
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Same patch as previous one, but for ebtables.
To build a kernel that only supports ebtables-nft, the builtin tables
need to be disabled, i.e.:
CONFIG_BRIDGE_EBT_BROUTE=n
CONFIG_BRIDGE_EBT_T_FILTER=n
CONFIG_BRIDGE_EBT_T_NAT=n
The ebtables specific extensions can then be used nftables'
NFT_COMPAT interface.
Signed-off-by: Florian Westphal <fw@strlen.de>
When compiling with gcc 13 and CONFIG_FORTIFY_SOURCE=y, the following
warning appears:
In function ‘fortify_memcpy_chk’,
inlined from ‘size_entry_mwt’ at net/bridge/netfilter/ebtables.c:2118:2:
./include/linux/fortify-string.h:592:25: error: call to ‘__read_overflow2_field’
declared with attribute warning: detected read beyond size of field (2nd parameter);
maybe use struct_group()? [-Werror=attribute-warning]
592 | __read_overflow2_field(q_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The compiler is complaining:
memcpy(&offsets[1], &entry->watchers_offset,
sizeof(offsets) - sizeof(offsets[0]));
where memcpy reads beyong &entry->watchers_offset to copy
{watchers,target,next}_offset altogether into offsets[]. Silence the
warning by wrapping these three up via struct_group().
Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
nftables equivalent for ebtables -t broute.
Implement broute meta statement to set br_netfilter_broute flag
in skb to force a packet to be routed instead of being bridged.
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Signed-off-by: Florian Westphal <fw@strlen.de>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
1) Fix broken listing of set elements when table has an owner.
2) Fix conntrack refcount leak in ctnetlink with related conntrack
entries, from Hangyu Hua.
3) Fix use-after-free/double-free in ctnetlink conntrack insert path,
from Florian Westphal.
4) Fix ip6t_rpfilter with VRF, from Phil Sutter.
5) Fix use-after-free in ebtables reported by syzbot, also from Florian.
6) Use skb->len in xt_length to deal with IPv6 jumbo packets,
from Xin Long.
7) Fix NETLINK_LISTEN_ALL_NSID with ctnetlink, from Florian Westphal.
8) Fix memleak in {ip_,ip6_,arp_}tables in ENOMEM error case,
from Pavel Tikhomirov.
* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: x_tables: fix percpu counter block leak on error path when creating new netns
netfilter: ctnetlink: make event listener tracking global
netfilter: xt_length: use skb len to match in length_mt6
netfilter: ebtables: fix table blob use-after-free
netfilter: ip6t_rpfilter: Fix regression with VRF interfaces
netfilter: conntrack: fix rmmod double-free race
netfilter: ctnetlink: fix possible refcount leak in ctnetlink_create_conntrack()
netfilter: nf_tables: allow to fetch set elements when table has an owner
====================
Link: https://lore.kernel.org/r/20230222092137.88637-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We are not allowed to return an error at this point.
Looking at the code it looks like ret is always 0 at this
point, but its not.
t = find_table_lock(net, repl->name, &ret, &ebt_mutex);
... this can return a valid table, with ret != 0.
This bug causes update of table->private with the new
blob, but then frees the blob right away in the caller.
Syzbot report:
BUG: KASAN: vmalloc-out-of-bounds in __ebt_unregister_table+0xc00/0xcd0 net/bridge/netfilter/ebtables.c:1168
Read of size 4 at addr ffffc90005425000 by task kworker/u4:4/74
Workqueue: netns cleanup_net
Call Trace:
kasan_report+0xbf/0x1f0 mm/kasan/report.c:517
__ebt_unregister_table+0xc00/0xcd0 net/bridge/netfilter/ebtables.c:1168
ebt_unregister_table+0x35/0x40 net/bridge/netfilter/ebtables.c:1372
ops_exit_list+0xb0/0x170 net/core/net_namespace.c:169
cleanup_net+0x4ee/0xb10 net/core/net_namespace.c:613
...
ip(6)tables appears to be ok (ret should be 0 at this point) but make
this more obvious.
Fixes: c58dd2dd44 ("netfilter: Can't fail and free after table replacement")
Reported-by: syzbot+f61594de72d6705aea03@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These 3 places in bridge netfilter are called on RX path after GRO
and IPv4 TCP GSO packets may come through, so replace iph tot_len
accessing with skb_ip_totlen() in there.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
No need to have distinct functions. After merge, ipv6 can avoid
protooff computation if the connection neither needs sequence adjustment
nor helper invocation -- this is the normal case.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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: 7997eff828 ("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>
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: 1da177e4c3 ("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>
Same as the existing ones, no conversions. This is just for sparse sake
only so that we no longer mix be16/u16 and be32/u32 types.
Alternative is to add __force __beX in various places, but this
seems nicer.
objdiff shows no changes.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
its enough to export the meta get reduce helper and then call it
from nft_meta_bridge too.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Output of expressions might be larger than one single register, this might
clobber existing data. Reset tracking for all destination registers that
required to store the expression output.
This patch adds three new helper functions:
- nft_reg_track_update: cancel previous register tracking and update it.
- nft_reg_track_cancel: cancel any previous register tracking info.
- __nft_reg_track_cancel: cancel only one single register tracking info.
Partial register clobbering detection is also supported by checking the
.num_reg field which describes the number of register that are used.
This patch updates the following expressions:
- meta_bridge
- bitwise
- byteorder
- meta
- payload
to use these helper functions.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Skip register tracking for expressions that perform read-only operations
on the registers. Define and use a cookie pointer NFT_REDUCE_READONLY to
avoid defining stubs for these expressions.
This patch re-enables register tracking which was disabled in ed5f85d422
("netfilter: nf_tables: disable register tracking"). Follow up patches
add remaining register tracking for existing expressions.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
1) Revert CHECKSUM_UNNECESSARY for UDP packet from conntrack.
2) Reject unsupported families when creating tables, from Phil Sutter.
3) GRE support for the flowtable, from Toshiaki Makita.
4) Add GRE offload support for act_ct, also from Toshiaki.
5) Update mlx5 driver to support for GRE flowtable offload,
from Toshiaki Makita.
6) Oneliner to clean up incorrect indentation in nf_conntrack_bridge,
from Jiapeng Chong.
* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
netfilter: bridge: clean up some inconsistent indenting
net/mlx5: Support GRE conntrack offload
act_ct: Support GRE offload
netfilter: flowtable: Support GRE
netfilter: nf_tables: Reject tables of unsupported family
Revert "netfilter: conntrack: mark UDP zero checksum as CHECKSUM_UNNECESSARY"
====================
Link: https://lore.kernel.org/r/20220315091513.66544-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
skb->tstamp was first used as the (rcv) timestamp.
The major usage is to report it to the user (e.g. SO_TIMESTAMP).
Later, skb->tstamp is also set as the (future) delivery_time (e.g. EDT in TCP)
during egress and used by the qdisc (e.g. sch_fq) to make decision on when
the skb can be passed to the dev.
Currently, there is no way to tell skb->tstamp having the (rcv) timestamp
or the delivery_time, so it is always reset to 0 whenever forwarded
between egress and ingress.
While it makes sense to always clear the (rcv) timestamp in skb->tstamp
to avoid confusing sch_fq that expects the delivery_time, it is a
performance issue [0] to clear the delivery_time if the skb finally
egress to a fq@phy-dev. For example, when forwarding from egress to
ingress and then finally back to egress:
tcp-sender => veth@netns => veth@hostns => fq@eth0@hostns
^ ^
reset rest
This patch adds one bit skb->mono_delivery_time to flag the skb->tstamp
is storing the mono delivery_time (EDT) instead of the (rcv) timestamp.
The current use case is to keep the TCP mono delivery_time (EDT) and
to be used with sch_fq. A latter patch will also allow tc-bpf@ingress
to read and change the mono delivery_time.
In the future, another bit (e.g. skb->user_delivery_time) can be added
for the SCM_TXTIME where the clock base is tracked by sk->sk_clockid.
[ This patch is a prep work. The following patches will
get the other parts of the stack ready first. Then another patch
after that will finally set the skb->mono_delivery_time. ]
skb_set_delivery_time() function is added. It is used by the tcp_output.c
and during ip[6] fragmentation to assign the delivery_time to
the skb->tstamp and also set the skb->mono_delivery_time.
A note on the change in ip_send_unicast_reply() in ip_output.c.
It is only used by TCP to send reset/ack out of a ctl_sk.
Like the new skb_set_delivery_time(), this patch sets
the skb->mono_delivery_time to 0 for now as a place
holder. It will be enabled in a latter patch.
A similar case in tcp_ipv6 can be done with
skb_set_delivery_time() in tcp_v6_send_response().
[0] (slide 22): https://linuxplumbersconf.org/event/11/contributions/953/attachments/867/1658/LPC_2021_BPF_Datapath_Extensions.pdf
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prior to commit fa538f7cf0 ("netfilter: nf_reject: add reject skbuff
creation helpers"), nft_reject_bridge did not assign to nskb->dev before
passing nskb on to br_forward(). The shared skbuff creation helpers
introduced in above commit do which seems to confuse br_forward() as
reject statements in prerouting hook won't emit a packet anymore.
Fix this by simply passing NULL instead of 'dev' to the helpers - they
use the pointer for just that assignment, nothing else.
Fixes: fa538f7cf0 ("netfilter: nf_reject: add reject skbuff creation helpers")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The meta expression might mangle the packet metadata, cancel register
tracking since any metadata in the registers is stale.
Finer grain register tracking cancellation by inspecting the meta type
on the register is also possible.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next:
1) Use array_size() in ebtables, from Gustavo A. R. Silva.
2) Attach IPS_ASSURED to internal UDP stream state, reported by
Maciej Zenczykowski.
3) Add NFT_META_IFTYPE to match on the interface type either
from ingress or egress.
4) Generalize pktinfo->tprot_set to flags field.
5) Allow to match on inner headers / payload data.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use array_size() helper instead of the open-coded version in
copy_{from,to}_user(). These sorts of multiplication factors
need to be wrapped in array_size().
Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This is possible now that the xt_table structure is passed via *priv.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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: 3c171f496e ("netfilter: bridge: add connection tracking system")
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If any of these modules is loaded, hooks get registered in all netns:
Before: 'unshare -n nft list hooks' shows:
family bridge hook prerouting {
-2147483648 ebt_broute
-0000000300 ebt_nat_hook
}
family bridge hook input {
-0000000200 ebt_filter_hook
}
family bridge hook forward {
-0000000200 ebt_filter_hook
}
family bridge hook output {
+0000000100 ebt_nat_hook
+0000000200 ebt_filter_hook
}
family bridge hook postrouting {
+0000000300 ebt_nat_hook
}
This adds 'template 'tables' for ebtables.
Each ebtable_foo registers the table as a template, with an init function
that gets called once the first get/setsockopt call is made.
ebtables core then searches the (per netns) list of tables.
If no table is found, it searches the list of templates instead.
If a template entry exists, the init function is called which will
enable the table and register the hooks (so packets are diverted
to the table).
If no entry is found in the template list, request_module is called.
After this, hook registration is delayed until the 'ebtables'
(set/getsockopt) request is made for a given table and will only
happen in the specific namespace.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The compat layer needs to parse untrusted input (the ruleset)
to translate it to a 64bit compatible format.
We had a number of bugs in this department in the past, so allow users
to turn this feature off.
Add CONFIG_NETFILTER_XTABLES_COMPAT kconfig knob and make it default to y
to keep existing behaviour.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ebtables stores the table internal data (what gets passed to the
ebt_do_table() interpreter) in struct net.
nftables keeps the internal interpreter format in pernet lists
and passes it via the netfilter core infrastructure (priv pointer).
Do the same for ebtables: the nf_hook_ops are duplicated via kmemdup,
then the ops->priv pointer is set to the table that is being registered.
After that, the netfilter core passes this table info to the hookfn.
This allows to remove the pointers from struct net.
Same pattern can be applied to ip/ip6/arptables.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
- keep the ZC code, drop the code related to reinit
net/bridge/netfilter/ebtables.c
- fix build after move to net_generic
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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: aee12a0a37 ("ebtables: remove nf_hook_register usage")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ebtables currently uses net->xt.tables[BRIDGE], but upcoming
patch will move net->xt.tables away from struct net.
To avoid exposing x_tables internals to ebtables, use a private list
instead.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Provide bridge log support from nf_log_syslog.
After the merge there is no need to load the "real packet loggers",
all of them now reside in the same module.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
Bridge family is using the same static init and dump function as inet.
This patch removes duplicate code unifying these functions body into
nft_reject.c so they can be reused in the rest of families supporting
reject verdict.
Signed-off-by: Jose M. Guisado Gomez <guigom@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Adds reject skbuff creation helper functions to ipv4/6 nf_reject
infrastructure. Use these functions for reject verdict in bridge
family.
Can be reused by all different families that support reject and
will not inject the reject packet through ip local out.
Signed-off-by: Jose M. Guisado Gomez <guigom@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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: c1a8311679 ("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>