linux-stable.git/net/openvswitch, branch linux-5.17.y

net: openvswitch: fix misuse of the cached connection on tuple changes

2022-06-14T16:41:47+00:00

commit 2061ecfdf2350994e5b61c43e50e98a7a70e95ee upstream.

If packet headers changed, the cached nfct is no longer relevant
for the packet and attempt to re-use it leads to the incorrect packet
classification.

This issue is causing broken connectivity in OpenStack deployments
with OVS/OVN due to hairpin traffic being unexpectedly dropped.

The setup has datapath flows with several conntrack actions and tuple
changes between them:

  actions:ct(commit,zone=8,mark=0/0x1,nat(src)),
          set(eth(src=00:00:00:00:00:01,dst=00:00:00:00:00:06)),
          set(ipv4(src=172.18.2.10,dst=192.168.100.6,ttl=62)),
          ct(zone=8),recirc(0x4)

After the first ct() action the packet headers are almost fully
re-written.  The next ct() tries to re-use the existing nfct entry
and marks the packet as invalid, so it gets dropped later in the
pipeline.

Clearing the cached conntrack entry whenever packet tuple is changed
to avoid the issue.

The flow key should not be cleared though, because we should still
be able to match on the ct_state if the recirculation happens after
the tuple change but before the next ct() action.

Cc: stable@vger.kernel.org
Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action")
Reported-by: Frode Nordahl 
Link: https://mail.openvswitch.org/pipermail/ovs-discuss/2022-May/051829.html
Link: https://bugs.launchpad.net/ubuntu/+source/ovn/+bug/1967856
Signed-off-by: Ilya Maximets 
Link: https://lore.kernel.org/r/20220606221140.488984-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

openvswitch: fix OOB access in reserve_sfa_size()

2022-04-27T12:41:14+00:00

commit cefa91b2332d7009bc0be5d951d6cbbf349f90f8 upstream.

Given a sufficiently large number of actions, while copying and
reserving memory for a new action of a new flow, if next_offset is
greater than MAX_ACTIONS_BUFSIZE, the function reserve_sfa_size() does
not return -EMSGSIZE as expected, but it allocates MAX_ACTIONS_BUFSIZE
bytes increasing actions_len by req_size. This can then lead to an OOB
write access, especially when further actions need to be copied.

Fix it by rearranging the flow action size check.

KASAN splat below:

==================================================================
BUG: KASAN: slab-out-of-bounds in reserve_sfa_size+0x1ba/0x380 [openvswitch]
Write of size 65360 at addr ffff888147e4001c by task handler15/836

CPU: 1 PID: 836 Comm: handler15 Not tainted 5.18.0-rc1+ #27
...
Call Trace:
 
 dump_stack_lvl+0x45/0x5a
 print_report.cold+0x5e/0x5db
 ? __lock_text_start+0x8/0x8
 ? reserve_sfa_size+0x1ba/0x380 [openvswitch]
 kasan_report+0xb5/0x130
 ? reserve_sfa_size+0x1ba/0x380 [openvswitch]
 kasan_check_range+0xf5/0x1d0
 memcpy+0x39/0x60
 reserve_sfa_size+0x1ba/0x380 [openvswitch]
 __add_action+0x24/0x120 [openvswitch]
 ovs_nla_add_action+0xe/0x20 [openvswitch]
 ovs_ct_copy_action+0x29d/0x1130 [openvswitch]
 ? __kernel_text_address+0xe/0x30
 ? unwind_get_return_address+0x56/0xa0
 ? create_prof_cpu_mask+0x20/0x20
 ? ovs_ct_verify+0xf0/0xf0 [openvswitch]
 ? prep_compound_page+0x198/0x2a0
 ? __kasan_check_byte+0x10/0x40
 ? kasan_unpoison+0x40/0x70
 ? ksize+0x44/0x60
 ? reserve_sfa_size+0x75/0x380 [openvswitch]
 __ovs_nla_copy_actions+0xc26/0x2070 [openvswitch]
 ? __zone_watermark_ok+0x420/0x420
 ? validate_set.constprop.0+0xc90/0xc90 [openvswitch]
 ? __alloc_pages+0x1a9/0x3e0
 ? __alloc_pages_slowpath.constprop.0+0x1da0/0x1da0
 ? unwind_next_frame+0x991/0x1e40
 ? __mod_node_page_state+0x99/0x120
 ? __mod_lruvec_page_state+0x2e3/0x470
 ? __kasan_kmalloc_large+0x90/0xe0
 ovs_nla_copy_actions+0x1b4/0x2c0 [openvswitch]
 ovs_flow_cmd_new+0x3cd/0xb10 [openvswitch]
 ...

Cc: stable@vger.kernel.org
Fixes: f28cd2af22a0 ("openvswitch: fix flow actions reallocation")
Signed-off-by: Paolo Valerio 
Acked-by: Eelco Chaudron 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: openvswitch: fix leak of nested actions

2022-04-13T17:27:32+00:00

[ Upstream commit 1f30fb9166d4f15a1aa19449b9da871fe0ed4796 ]

While parsing user-provided actions, openvswitch module may dynamically
allocate memory and store pointers in the internal copy of the actions.
So this memory has to be freed while destroying the actions.

Currently there are only two such actions: ct() and set().  However,
there are many actions that can hold nested lists of actions and
ovs_nla_free_flow_actions() just jumps over them leaking the memory.

For example, removal of the flow with the following actions will lead
to a leak of the memory allocated by nf_ct_tmpl_alloc():

  actions:clone(ct(commit),0)

Non-freed set() action may also leak the 'dst' structure for the
tunnel info including device references.

Under certain conditions with a high rate of flow rotation that may
cause significant memory leak problem (2MB per second in reporter's
case).  The problem is also hard to mitigate, because the user doesn't
have direct control over the datapath flows generated by OVS.

Fix that by iterating over all the nested actions and freeing
everything that needs to be freed recursively.

New build time assertion should protect us from this problem if new
actions will be added in the future.

Unfortunately, openvswitch module doesn't use NLA_F_NESTED, so all
attributes has to be explicitly checked.  sample() and clone() actions
are mixing extra attributes into the user-provided action list.  That
prevents some code generalization too.

Fixes: 34ae932a4036 ("openvswitch: Make tunnel set action attach a metadata dst")
Link: https://mail.openvswitch.org/pipermail/ovs-dev/2022-March/392922.html
Reported-by: Stéphane Graber 
Signed-off-by: Ilya Maximets 
Acked-by: Aaron Conole 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: openvswitch: don't send internal clone attribute to the userspace.

2022-04-13T17:27:32+00:00

[ Upstream commit 3f2a3050b4a3e7f32fc0ea3c9b0183090ae00522 ]

'OVS_CLONE_ATTR_EXEC' is an internal attribute that is used for
performance optimization inside the kernel.  It's added by the kernel
while parsing user-provided actions and should not be sent during the
flow dump as it's not part of the uAPI.

The issue doesn't cause any significant problems to the ovs-vswitchd
process, because reported actions are not really used in the
application lifecycle and only supposed to be shown to a human via
ovs-dpctl flow dump.  However, the action list is still incorrect
and causes the following error if the user wants to look at the
datapath flows:

  # ovs-dpctl add-dp system@ovs-system
  # ovs-dpctl add-flow "" "clone(ct(commit),0)"
  # ovs-dpctl dump-flows
  , packets:0, bytes:0, used:never,
    actions:clone(bad length 4, expected -1 for: action0(01 00 00 00),
                  ct(commit),0)

With the fix:

  # ovs-dpctl dump-flows
  , packets:0, bytes:0, used:never,
    actions:clone(ct(commit),0)

Additionally fixed an incorrect attribute name in the comment.

Fixes: b233504033db ("openvswitch: kernel datapath clone action")
Signed-off-by: Ilya Maximets 
Acked-by: Aaron Conole 
Link: https://lore.kernel.org/r/20220404104150.2865736-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

openvswitch: Fixed nd target mask field in the flow dump.

2022-04-08T11:59:03+00:00

commit f19c44452b58a84d95e209b847f5495d91c9983a upstream.

IPv6 nd target mask was not getting populated in flow dump.

In the function __ovs_nla_put_key the icmp code mask field was checked
instead of icmp code key field to classify the flow as neighbour discovery.

ufid:bdfbe3e5-60c2-43b0-a5ff-dfcac1c37328, recirc_id(0),dp_hash(0/0),
skb_priority(0/0),in_port(ovs-nm1),skb_mark(0/0),ct_state(0/0),
ct_zone(0/0),ct_mark(0/0),ct_label(0/0),
eth(src=00:00:00:00:00:00/00:00:00:00:00:00,
dst=00:00:00:00:00:00/00:00:00:00:00:00),
eth_type(0x86dd),
ipv6(src=::/::,dst=::/::,label=0/0,proto=58,tclass=0/0,hlimit=0/0,frag=no),
icmpv6(type=135,code=0),
nd(target=2001::2/::,
sll=00:00:00:00:00:00/00:00:00:00:00:00,
tll=00:00:00:00:00:00/00:00:00:00:00:00),
packets:10, bytes:860, used:0.504s, dp:ovs, actions:ovs-nm2

Fixes: e64457191a25 (openvswitch: Restructure datapath.c and flow.c)
Signed-off-by: Martin Varghese 
Link: https://lore.kernel.org/r/20220328054148.3057-1-martinvarghesenokia@gmail.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

openvswitch: always update flow key after nat

2022-04-08T11:58:22+00:00

[ Upstream commit 60b44ca6bd7518dd38fa2719bc9240378b6172c3 ]

During NAT, a tuple collision may occur.  When this happens, openvswitch
will make a second pass through NAT which will perform additional packet
modification.  This will update the skb data, but not the flow key that
OVS uses.  This means that future flow lookups, and packet matches will
have incorrect data.  This has been supported since
5d50aa83e2c8 ("openvswitch: support asymmetric conntrack").

That commit failed to properly update the sw_flow_key attributes, since
it only called the ovs_ct_nat_update_key once, rather than each time
ovs_ct_nat_execute was called.  As these two operations are linked, the
ovs_ct_nat_execute() function should always make sure that the
sw_flow_key is updated after a successful call through NAT infrastructure.

Fixes: 5d50aa83e2c8 ("openvswitch: support asymmetric conntrack")
Cc: Dumitru Ceara 
Cc: Numan Siddique 
Signed-off-by: Aaron Conole 
Acked-by: Eelco Chaudron 
Link: https://lore.kernel.org/r/20220318124319.3056455-1-aconole@redhat.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

openvswitch: Fix setting ipv6 fields causing hw csum failure

2022-02-24T17:16:21+00:00

Ipv6 ttl, label and tos fields are modified without first
pulling/pushing the ipv6 header, which would have updated
the hw csum (if available). This might cause csum validation
when sending the packet to the stack, as can be seen in
the trace below.

Fix this by updating skb->csum if available.

Trace resulted by ipv6 ttl dec and then sending packet
to conntrack [actions: set(ipv6(hlimit=63)),ct(zone=99)]:
[295241.900063] s_pf0vf2: hw csum failure
[295241.923191] Call Trace:
[295241.925728]  
[295241.927836]  dump_stack+0x5c/0x80
[295241.931240]  __skb_checksum_complete+0xac/0xc0
[295241.935778]  nf_conntrack_tcp_packet+0x398/0xba0 [nf_conntrack]
[295241.953030]  nf_conntrack_in+0x498/0x5e0 [nf_conntrack]
[295241.958344]  __ovs_ct_lookup+0xac/0x860 [openvswitch]
[295241.968532]  ovs_ct_execute+0x4a7/0x7c0 [openvswitch]
[295241.979167]  do_execute_actions+0x54a/0xaa0 [openvswitch]
[295242.001482]  ovs_execute_actions+0x48/0x100 [openvswitch]
[295242.006966]  ovs_dp_process_packet+0x96/0x1d0 [openvswitch]
[295242.012626]  ovs_vport_receive+0x6c/0xc0 [openvswitch]
[295242.028763]  netdev_frame_hook+0xc0/0x180 [openvswitch]
[295242.034074]  __netif_receive_skb_core+0x2ca/0xcb0
[295242.047498]  netif_receive_skb_internal+0x3e/0xc0
[295242.052291]  napi_gro_receive+0xba/0xe0
[295242.056231]  mlx5e_handle_rx_cqe_mpwrq_rep+0x12b/0x250 [mlx5_core]
[295242.062513]  mlx5e_poll_rx_cq+0xa0f/0xa30 [mlx5_core]
[295242.067669]  mlx5e_napi_poll+0xe1/0x6b0 [mlx5_core]
[295242.077958]  net_rx_action+0x149/0x3b0
[295242.086762]  __do_softirq+0xd7/0x2d6
[295242.090427]  irq_exit+0xf7/0x100
[295242.093748]  do_IRQ+0x7f/0xd0
[295242.096806]  common_interrupt+0xf/0xf
[295242.100559]  
[295242.102750] RIP: 0033:0x7f9022e88cbd
[295242.125246] RSP: 002b:00007f9022282b20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffda
[295242.132900] RAX: 0000000000000005 RBX: 0000000000000010 RCX: 0000000000000000
[295242.140120] RDX: 00007f9022282ba8 RSI: 00007f9022282a30 RDI: 00007f9014005c30
[295242.147337] RBP: 00007f9014014d60 R08: 0000000000000020 R09: 00007f90254a8340
[295242.154557] R10: 00007f9022282a28 R11: 0000000000000246 R12: 0000000000000000
[295242.161775] R13: 00007f902308c000 R14: 000000000000002b R15: 00007f9022b71f40

Fixes: 3fdbd1ce11e5 ("openvswitch: add ipv6 'set' action")
Signed-off-by: Paul Blakey 
Link: https://lore.kernel.org/r/20220223163416.24096-1-paulb@nvidia.com
Signed-off-by: Jakub Kicinski

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

2022-01-10T01:00:17+00:00

Merge in fixes directly in prep for the 5.17 merge window.
No conflicts.

Signed-off-by: Jakub Kicinski

net: openvswitch: Fix ct_state nat flags for conns arriving from tc

2022-01-10T00:24:12+00:00

Netfilter conntrack maintains NAT flags per connection indicating
whether NAT was configured for the connection. Openvswitch maintains
NAT flags on the per packet flow key ct_state field, indicating
whether NAT was actually executed on the packet.

When a packet misses from tc to ovs the conntrack NAT flags are set.
However, NAT was not necessarily executed on the packet because the
connection's state might still be in NEW state. As such, openvswitch
wrongly assumes that NAT was executed and sets an incorrect flow key
NAT flags.

Fix this, by flagging to openvswitch which NAT was actually done in
act_ct via tc_skb_ext and tc_skb_cb to the openvswitch module, so
the packet flow key NAT flags will be correctly set.

Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct")
Signed-off-by: Paul Blakey 
Acked-by: Jamal Hadi Salim 
Link: https://lore.kernel.org/r/20220106153804.26451-1-paulb@nvidia.com
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

2022-01-09T23:59:23+00:00

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next. This
includes one patch to update ovs and act_ct to use nf_ct_put() instead
of nf_conntrack_put().

1) Add netns_tracker to nfnetlink_log and masquerade, from Eric Dumazet.

2) Remove redundant rcu read-size lock in nf_tables packet path.

3) Replace BUG() by WARN_ON_ONCE() in nft_payload.

4) Consolidate rule verdict tracing.

5) Replace WARN_ON() by WARN_ON_ONCE() in nf_tables core.

6) Make counter support built-in in nf_tables.

7) Add new field to conntrack object to identify locally generated
   traffic, from Florian Westphal.

8) Prevent NAT from shadowing well-known ports, from Florian Westphal.

9) Merge nf_flow_table_{ipv4,ipv6} into nf_flow_table_inet, also from
   Florian.

10) Remove redundant pointer in nft_pipapo AVX2 support, from Colin Ian King.

11) Replace opencoded max() in conntrack, from Jiapeng Chong.

12) Update conntrack to use refcount_t API, from Florian Westphal.

13) Move ip_ct_attach indirection into the nf_ct_hook structure.

14) Constify several pointer object in the netfilter codebase,
    from Florian Westphal.

15) Tree-wide replacement of nf_conntrack_put() by nf_ct_put(), also
    from Florian.

16) Fix egress splat due to incorrect rcu notation, from Florian.

17) Move stateful fields of connlimit, last, quota, numgen and limit
    out of the expression data area.

18) Build a blob to represent the ruleset in nf_tables, this is a
    requirement of the new register tracking infrastructure.

19) Add NFT_REG32_NUM to define the maximum number of 32-bit registers.

20) Add register tracking infrastructure to skip redundant
    store-to-register operations, this includes support for payload,
    meta and bitwise expresssions.

* git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next: (32 commits)
  netfilter: nft_meta: cancel register tracking after meta update
  netfilter: nft_payload: cancel register tracking after payload update
  netfilter: nft_bitwise: track register operations
  netfilter: nft_meta: track register operations
  netfilter: nft_payload: track register operations
  netfilter: nf_tables: add register tracking infrastructure
  netfilter: nf_tables: add NFT_REG32_NUM
  netfilter: nf_tables: add rule blob layout
  netfilter: nft_limit: move stateful fields out of expression data
  netfilter: nft_limit: rename stateful structure
  netfilter: nft_numgen: move stateful fields out of expression data
  netfilter: nft_quota: move stateful fields out of expression data
  netfilter: nft_last: move stateful fields out of expression data
  netfilter: nft_connlimit: move stateful fields out of expression data
  netfilter: egress: avoid a lockdep splat
  net: prefer nf_ct_put instead of nf_conntrack_put
  netfilter: conntrack: avoid useless indirection during conntrack destruction
  netfilter: make function op structures const
  netfilter: core: move ip_ct_attach indirection to struct nf_ct_hook
  netfilter: conntrack: convert to refcount_t api
  ...
====================

Link: https://lore.kernel.org/r/20220109231640.104123-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski