linux-stable.git/net/netfilter, branch v5.4.11

netfilter: nf_tables_offload: return EOPNOTSUPP if rule specifies no actions

2020-01-12T11:21:18+00:00

[ Upstream commit 81ec61074bcf68acfcb2820cda3ff9d9984419c7 ]

If the rule only specifies the matching side, return EOPNOTSUPP.
Otherwise, the front-end relies on the drivers to reject this rule.

Fixes: c9626a2cbdb2 ("netfilter: nf_tables: add hardware offload support")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: skip module reference count bump on object updates

2020-01-12T11:21:18+00:00

[ Upstream commit fd57d0cbe187e93f63777d36e9f49293311d417f ]

Use __nft_obj_type_get() instead, otherwise there is a module reference
counter leak.

Fixes: d62d0ba97b58 ("netfilter: nf_tables: Introduce stateful object update operation")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: validate NFT_DATA_VALUE after nft_data_init()

2020-01-12T11:21:18+00:00

[ Upstream commit 0d2c96af797ba149e559c5875c0151384ab6dd14 ]

Userspace might bogusly sent NFT_DATA_VERDICT in several netlink
attributes that assume NFT_DATA_VALUE. Moreover, make sure that error
path invokes nft_data_release() to decrement the reference count on the
chain object.

Fixes: 96518518cc41 ("netfilter: add nftables")
Fixes: 0f3cd9b36977 ("netfilter: nf_tables: add range expression")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: validate NFT_SET_ELEM_INTERVAL_END

2020-01-12T11:21:18+00:00

[ Upstream commit bffc124b6fe37d0ae9b428d104efb426403bb5c9 ]

Only NFTA_SET_ELEM_KEY and NFTA_SET_ELEM_FLAGS make sense for elements
whose NFT_SET_ELEM_INTERVAL_END flag is set on.

Fixes: 96518518cc41 ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nft_set_rbtree: bogus lookup/get on consecutive elements in named sets

2020-01-12T11:21:18+00:00

[ Upstream commit db3b665dd77b34e34df00e17d7b299c98fcfb2c5 ]

The existing rbtree implementation might store consecutive elements
where the closing element and the opening element might overlap, eg.

	[ a, a+1) [ a+1, a+2)

This patch removes the optimization for non-anonymous sets in the exact
matching case, where it is assumed to stop searching in case that the
closing element is found. Instead, invalidate candidate interval and
keep looking further in the tree.

The lookup/get operation might return false, while there is an element
in the rbtree. Moreover, the get operation returns true as if a+2 would
be in the tree. This happens with named sets after several set updates.

The existing lookup optimization (that only works for the anonymous
sets) might not reach the opening [ a+1,... element if the closing
...,a+1) is found in first place when walking over the rbtree. Hence,
walking the full tree in that case is needed.

This patch fixes the lookup and get operations.

Fixes: e701001e7cbe ("netfilter: nft_rbtree: allow adjacent intervals with dynamic updates")
Fixes: ba0e4d9917b4 ("netfilter: nf_tables: get set elements via netlink")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables_offload: Check for the NETDEV_UNREGISTER event

2020-01-12T11:21:14+00:00

[ Upstream commit d1f4c966475c6dd2545c6625022cb24e878bee11 ]

Check for the NETDEV_UNREGISTER event from the nft_offload_netdev_event
function, which is the event that actually triggers the clean up.

Fixes: 06d392cbe3db ("netfilter: nf_tables_offload: remove rules when the device unregisters")
Signed-off-by: wenxu 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: ctnetlink: netns exit must wait for callbacks

2020-01-12T11:21:13+00:00

[ Upstream commit 18a110b022a5c02e7dc9f6109d0bd93e58ac6ebb ]

Curtis Taylor and Jon Maxwell reported and debugged a crash on 3.10
based kernel.

Crash occurs in ctnetlink_conntrack_events because net->nfnl socket is
NULL.  The nfnl socket was set to NULL by netns destruction running on
another cpu.

The exiting network namespace calls the relevant destructors in the
following order:

1. ctnetlink_net_exit_batch

This nulls out the event callback pointer in struct netns.

2. nfnetlink_net_exit_batch

This nulls net->nfnl socket and frees it.

3. nf_conntrack_cleanup_net_list

This removes all remaining conntrack entries.

This is order is correct. The only explanation for the crash so ar is:

cpu1: conntrack is dying, eviction occurs:
 -> nf_ct_delete()
   -> nf_conntrack_event_report \
     -> nf_conntrack_eventmask_report
       -> notify->fcn() (== ctnetlink_conntrack_events).

cpu1: a. fetches rcu protected pointer to obtain ctnetlink event callback.
      b. gets interrupted.
 cpu2: runs netns exit handlers:
     a runs ctnetlink destructor, event cb pointer set to NULL.
     b runs nfnetlink destructor, nfnl socket is closed and set to NULL.
cpu1: c. resumes and trips over NULL net->nfnl.

Problem appears to be that ctnetlink_net_exit_batch only prevents future
callers of nf_conntrack_eventmask_report() from obtaining the callback.
It doesn't wait of other cpus that might have already obtained the
callbacks address.

I don't see anything in upstream kernels that would prevent similar
crash: We need to wait for all cpus to have exited the event callback.

Fixes: 9592a5c01e79dbc59eb56fa ("netfilter: ctnetlink: netns support")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_queue: enqueue skbs with NULL dst

2020-01-09T09:20:03+00:00

commit 0b9173f4688dfa7c5d723426be1d979c24ce3d51 upstream.

Bridge packets that are forwarded have skb->dst == NULL and get
dropped by the check introduced by
b60a77386b1d4868f72f6353d35dabe5fbe981f2 (net: make skb_dst_force
return true when dst is refcounted).

To fix this we check skb_dst() before skb_dst_force(), so we don't
drop skb packet with dst == NULL. This holds also for skb at the
PRE_ROUTING hook so we remove the second check.

Fixes: b60a77386b1d ("net: make skb_dst_force return true when dst is refcounted")
Signed-off-by: Marco Oliverio 
Signed-off-by: Rocco Folino 
Acked-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: nft_tproxy: Fix port selector on Big Endian

2020-01-09T09:19:54+00:00

[ Upstream commit 8cb4ec44de42b99b92399b4d1daf3dc430ed0186 ]

On Big Endian architectures, u16 port value was extracted from the wrong
parts of u32 sreg_port, just like commit 10596608c4d62 ("netfilter:
nf_tables: fix mismatch in big-endian system") describes.

Fixes: 4ed8eb6570a49 ("netfilter: nf_tables: Add native tproxy support")
Signed-off-by: Phil Sutter 
Acked-by: Florian Westphal 
Acked-by: Máté Eckl 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

net: add bool confirm_neigh parameter for dst_ops.update_pmtu

2020-01-04T18:18:58+00:00

[ 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 
Reviewed-by: Guillaume Nault 
Acked-by: David Ahern 
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman