linux.git/net/netfilter, branch v5.9-rc4

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-09-04T01:50:48+00:00

Pull networking fixes from David Miller:

 1) Use netif_rx_ni() when necessary in batman-adv stack, from Jussi
    Kivilinna.

 2) Fix loss of RTT samples in rxrpc, from David Howells.

 3) Memory leak in hns_nic_dev_probe(), from Dignhao Liu.

 4) ravb module cannot be unloaded, fix from Yuusuke Ashizuka.

 5) We disable BH for too lokng in sctp_get_port_local(), add a
    cond_resched() here as well, from Xin Long.

 6) Fix memory leak in st95hf_in_send_cmd, from Dinghao Liu.

 7) Out of bound access in bpf_raw_tp_link_fill_link_info(), from
    Yonghong Song.

 8) Missing of_node_put() in mt7530 DSA driver, from Sumera
    Priyadarsini.

 9) Fix crash in bnxt_fw_reset_task(), from Michael Chan.

10) Fix geneve tunnel checksumming bug in hns3, from Yi Li.

11) Memory leak in rxkad_verify_response, from Dinghao Liu.

12) In tipc, don't use smp_processor_id() in preemptible context. From
    Tuong Lien.

13) Fix signedness issue in mlx4 memory allocation, from Shung-Hsi Yu.

14) Missing clk_disable_prepare() in gemini driver, from Dan Carpenter.

15) Fix ABI mismatch between driver and firmware in nfp, from Louis
    Peens.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (110 commits)
  net/smc: fix sock refcounting in case of termination
  net/smc: reset sndbuf_desc if freed
  net/smc: set rx_off for SMCR explicitly
  net/smc: fix toleration of fake add_link messages
  tg3: Fix soft lockup when tg3_reset_task() fails.
  doc: net: dsa: Fix typo in config code sample
  net: dp83867: Fix WoL SecureOn password
  nfp: flower: fix ABI mismatch between driver and firmware
  tipc: fix shutdown() of connectionless socket
  ipv6: Fix sysctl max for fib_multipath_hash_policy
  drivers/net/wan/hdlc: Change the default of hard_header_len to 0
  net: gemini: Fix another missing clk_disable_unprepare() in probe
  net: bcmgenet: fix mask check in bcmgenet_validate_flow()
  amd-xgbe: Add support for new port mode
  net: usb: dm9601: Add USB ID of Keenetic Plus DSL
  vhost: fix typo in error message
  net: ethernet: mlx4: Fix memory allocation in mlx4_buddy_init()
  pktgen: fix error message with wrong function name
  net: ethernet: ti: am65-cpsw: fix rmii 100Mbit link mode
  cxgb4: fix thermal zone device registration
  ...

netfilter: conntrack: do not auto-delete clash entries on reply

2020-08-29T11:03:06+00:00

Its possible that we have more than one packet with the same ct tuple
simultaneously, e.g. when an application emits n packets on same UDP
socket from multiple threads.

NAT rules might be applied to those packets. With the right set of rules,
n packets will be mapped to m destinations, where at least two packets end
up with the same destination.

When this happens, the existing clash resolution may merge the skb that
is processed after the first has been received with the identical tuple
already in hash table.

However, its possible that this identical tuple is a NAT_CLASH tuple.
In that case the second skb will be sent, but no reply can be received
since the reply that is processed first removes the NAT_CLASH tuple.

Do not auto-delete, this gives a 1 second window for replies to be passed
back to originator.

Packets that are coming later (udp stream case) will not be affected:
they match the original ct entry, not a NAT_CLASH one.

Also prevent NAT_CLASH entries from getting offloaded.

Fixes: 6a757c07e51f ("netfilter: conntrack: allow insertion of clashing entries")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: nfnetlink: nfnetlink_unicast() reports EAGAIN instead of ENOBUFS

2020-08-28T18:11:58+00:00

Frontend callback reports EAGAIN to nfnetlink to retry a command, this
is used to signal that module autoloading is required. Unfortunately,
nlmsg_unicast() reports EAGAIN in case the receiver socket buffer gets
full, so it enters a busy-loop.

This patch updates nfnetlink_unicast() to turn EAGAIN into ENOBUFS and
to use nlmsg_unicast(). Remove the flags field in nfnetlink_unicast()
since this is always MSG_DONTWAIT in the existing code which is exactly
what nlmsg_unicast() passes to netlink_unicast() as parameter.

Fixes: 96518518cc41 ("netfilter: add nftables")
Reported-by: Phil Sutter 
Signed-off-by: Pablo Neira Ayuso

netfilter: delete repeated words

2020-08-28T18:11:38+00:00

Drop duplicated words in net/netfilter/ and net/ipv4/netfilter/.

Signed-off-by: Randy Dunlap 
Reviewed-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva

netfilter: nf_tables: fix destination register zeroing

2020-08-21T17:00:33+00:00

Following bug was reported via irc:
nft list ruleset
   set knock_candidates_ipv4 {
      type ipv4_addr . inet_service
      size 65535
      elements = { 127.0.0.1 . 123,
                   127.0.0.1 . 123 }
      }
 ..
   udp dport 123 add @knock_candidates_ipv4 { ip saddr . 123 }
   udp dport 123 add @knock_candidates_ipv4 { ip saddr . udp dport }

It should not have been possible to add a duplicate set entry.

After some debugging it turned out that the problem is the immediate
value (123) in the second-to-last rule.

Concatenations use 32bit registers, i.e. the elements are 8 bytes each,
not 6 and it turns out the kernel inserted

inet firewall @knock_candidates_ipv4
        element 0100007f ffff7b00  : 0 [end]
        element 0100007f 00007b00  : 0 [end]

Note the non-zero upper bits of the first element.  It turns out that
nft_immediate doesn't zero the destination register, but this is needed
when the length isn't a multiple of 4.

Furthermore, the zeroing in nft_payload is broken.  We can't use
[len / 4] = 0 -- if len is a multiple of 4, index is off by one.

Skip zeroing in this case and use a conditional instead of (len -1) / 4.

Fixes: 49499c3e6e18 ("netfilter: nf_tables: switch registers to 32 bit addressing")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: add NFTA_SET_USERDATA if not null

2020-08-21T17:00:14+00:00

Kernel sends an empty NFTA_SET_USERDATA attribute with no value if
userspace adds a set with no NFTA_SET_USERDATA attribute.

Fixes: e6d8ecac9e68 ("netfilter: nf_tables: Add new attributes into nft_set to store user data.")
Signed-off-by: Pablo Neira Ayuso

netfilter: nft_set_rbtree: Detect partial overlap with start endpoint match

2020-08-21T15:37:36+00:00

Getting creative with nft and omitting the interval_overlap()
check from the set_overlap() function, without omitting
set_overlap() altogether, led to the observation of a partial
overlap that wasn't detected, and would actually result in
replacement of the end element of an existing interval.

This is due to the fact that we'll return -EEXIST on a matching,
pre-existing start element, instead of -ENOTEMPTY, and the error
is cleared by API if NLM_F_EXCL is not given. At this point, we
can insert a matching start, and duplicate the end element as long
as we don't end up into other intervals.

For instance, inserting interval 0 - 2 with an existing 0 - 3
interval would result in a single 0 - 2 interval, and a dangling
'3' end element. This is because nft will proceed after inserting
the '0' start element as no error is reported, and no further
conflicting intervals are detected on insertion of the end element.

This needs a different approach as it's a local condition that can
be detected by looking for duplicate ends coming from left and
right, separately. Track those and directly report -ENOTEMPTY on
duplicated end elements for a matching start.

Signed-off-by: Stefano Brivio 
Signed-off-by: Pablo Neira Ayuso

netfilter: nft_set_rbtree: Handle outcomes of tree rotations in overlap detection

2020-08-21T15:36:52+00:00

Checks for partial overlaps on insertion assume that end elements
are always descendant nodes of their corresponding start, because
they are inserted later. However, this is not the case if a
previous delete operation caused a tree rotation as part of
rebalancing.

Taking the issue reported by Andreas Fischer as an example, if we
omit delete operations, the existing procedure works because,
equivalently, we are inserting a start item with value 40 in the
this region of the red-black tree with single-sized intervals:

                                  overlap flag
                   10 (start)
                  /  \            false
                      20 (start)
                     /  \         false
                         30 (start)
                        /  \      false
                            60 (start)
                           /  \   false
                         50 (end)
                        /  \      false
                      20 (end)
                     /  \         false
                         40 (start)

if we now delete interval 30 - 30, the tree can be rearranged in
a way similar to this (note the rotation involving 50 - 50):

                                  overlap flag
                   10 (start)
                  /  \            false
                      20 (start)
                     /  \         false
                         25 (start)
                        /  \      false
                            70 (start)
                           /  \   false
                         50 (end)
                        /  \      true (from rule a1.)
                      50 (start)
                     /  \         true
                   40 (start)

and we traverse interval 50 - 50 from the opposite direction
compared to what was expected.

To deal with those cases, add a start-before-start rule, b4.,
that covers traversal of existing intervals from the right.

We now need to restrict start-after-end rule b3. to cases
where there are no occurring nodes between existing start and
end elements, because addition of rule b4. isn't sufficient to
ensure that the pre-existing end element we encounter while
descending the tree corresponds to a start element of an
interval that we already traversed entirely.

Different types of overlap detection on trees with rotations
resulting from re-balancing will be covered by nft test case
sets/0044interval_overlap_1.

Reported-by: Andreas Fischer 
Bugzilla: https://bugzilla.netfilter.org/show_bug.cgi?id=1449
Cc:  # 5.6.x
Fixes: 7c84d41416d8 ("netfilter: nft_set_rbtree: Detect partial overlaps on insertion")
Signed-off-by: Stefano Brivio 
Signed-off-by: Pablo Neira Ayuso

netfilter: conntrack: allow sctp hearbeat after connection re-use

2020-08-20T12:13:49+00:00

If an sctp connection gets re-used, heartbeats are flagged as invalid
because their vtag doesn't match.

Handle this in a similar way as TCP conntrack when it suspects that the
endpoints and conntrack are out-of-sync.

When a HEARTBEAT request fails its vtag validation, flag this in the
conntrack state and accept the packet.

When a HEARTBEAT_ACK is received with an invalid vtag in the reverse
direction after we allowed such a HEARTBEAT through, assume we are
out-of-sync and re-set the vtag info.

v2: remove left-over snippet from an older incarnation that moved
    new_state/old_state assignments, thats not needed so keep that
    as-is.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso