linux-stable.git/net/openvswitch, branch v6.9.3

net: openvswitch: fix overwriting ct original tuple for ICMPv6

2024-05-30T07:44:37+00:00

[ Upstream commit 7c988176b6c16c516474f6fceebe0f055af5eb56 ]

OVS_PACKET_CMD_EXECUTE has 3 main attributes:
- OVS_PACKET_ATTR_KEY - Packet metadata in a netlink format.
- OVS_PACKET_ATTR_PACKET - Binary packet content.
- OVS_PACKET_ATTR_ACTIONS - Actions to execute on the packet.

OVS_PACKET_ATTR_KEY is parsed first to populate sw_flow_key structure
with the metadata like conntrack state, input port, recirculation id,
etc. Then the packet itself gets parsed to populate the rest of the
keys from the packet headers.

Whenever the packet parsing code starts parsing the ICMPv6 header, it
first zeroes out fields in the key corresponding to Neighbor Discovery
information even if it is not an ND packet.

It is an 'ipv6.nd' field. However, the 'ipv6' is a union that shares
the space between 'nd' and 'ct_orig' that holds the original tuple
conntrack metadata parsed from the OVS_PACKET_ATTR_KEY.

ND packets should not normally have conntrack state, so it's fine to
share the space, but normal ICMPv6 Echo packets or maybe other types of
ICMPv6 can have the state attached and it should not be overwritten.

The issue results in all but the last 4 bytes of the destination
address being wiped from the original conntrack tuple leading to
incorrect packet matching and potentially executing wrong actions
in case this packet recirculates within the datapath or goes back
to userspace.

ND fields should not be accessed in non-ND packets, so not clearing
them should be fine. Executing memset() only for actual ND packets to
avoid the issue.

Initializing the whole thing before parsing is needed because ND packet
may not contain all the options.

The issue only affects the OVS_PACKET_CMD_EXECUTE path and doesn't
affect packets entering OVS datapath from network interfaces, because
in this case CT metadata is populated from skb after the packet is
already parsed.

Fixes: 9dd7f8907c37 ("openvswitch: Add original direction conntrack tuple to sw_flow_key.")
Reported-by: Antonin Bas
Closes: https://github.com/openvswitch/ovs-issues/issues/327
Signed-off-by: Ilya Maximets
Acked-by: Aaron Conole
Acked-by: Eelco Chaudron
Link: https://lore.kernel.org/r/20240509094228.1035477-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski
Signed-off-by: Sasha Levin

net: openvswitch: Fix Use-After-Free in ovs_ct_exit

2024-04-25T00:14:24+00:00

Since kfree_rcu, which is called in the hlist_for_each_entry_rcu traversal
of ovs_ct_limit_exit, is not part of the RCU read critical section, it
is possible that the RCU grace period will pass during the traversal and
the key will be free.

To prevent this, it should be changed to hlist_for_each_entry_safe.

Fixes: 11efd5cb04a1 ("openvswitch: Support conntrack zone limit")
Signed-off-by: Hyunwoo Kim 
Reviewed-by: Eric Dumazet 
Reviewed-by: Aaron Conole 
Link: https://lore.kernel.org/r/ZiYvzQN/Ry5oeFQW@v4bel-B760M-AORUS-ELITE-AX
Signed-off-by: Jakub Kicinski

net: openvswitch: fix unwanted error log on timeout policy probing

2024-04-06T05:16:06+00:00

On startup, ovs-vswitchd probes different datapath features including
support for timeout policies.  While probing, it tries to execute
certain operations with OVS_PACKET_ATTR_PROBE or OVS_FLOW_ATTR_PROBE
attributes set.  These attributes tell the openvswitch module to not
log any errors when they occur as it is expected that some of the
probes will fail.

For some reason, setting the timeout policy ignores the PROBE attribute
and logs a failure anyway.  This is causing the following kernel log
on each re-start of ovs-vswitchd:

  kernel: Failed to associated timeout policy `ovs_test_tp'

Fix that by using the same logging macro that all other messages are
using.  The message will still be printed at info level when needed
and will be rate limited, but with a net rate limiter instead of
generic printk one.

The nf_ct_set_timeout() itself will still print some info messages,
but at least this change makes logging in openvswitch module more
consistent.

Fixes: 06bd2bdf19d2 ("openvswitch: Add timeout support to ct action")
Signed-off-by: Ilya Maximets 
Acked-by: Eelco Chaudron 
Link: https://lore.kernel.org/r/20240403203803.2137962-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski

net: openvswitch: limit the number of recursions from action sets

2024-02-09T20:54:38+00:00

The ovs module allows for some actions to recursively contain an action
list for complex scenarios, such as sampling, checking lengths, etc.
When these actions are copied into the internal flow table, they are
evaluated to validate that such actions make sense, and these calls
happen recursively.

The ovs-vswitchd userspace won't emit more than 16 recursion levels
deep.  However, the module has no such limit and will happily accept
limits larger than 16 levels nested.  Prevent this by tracking the
number of recursions happening and manually limiting it to 16 levels
nested.

The initial implementation of the sample action would track this depth
and prevent more than 3 levels of recursion, but this was removed to
support the clone use case, rather than limited at the current userspace
limit.

Fixes: 798c166173ff ("openvswitch: Optimize sample action for the clone use cases")
Signed-off-by: Aaron Conole 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/20240207132416.1488485-2-aconole@redhat.com
Signed-off-by: Jakub Kicinski

net/sched: act_ct: Always fill offloading tuple iifidx

2023-11-09T01:47:08+00:00

Referenced commit doesn't always set iifidx when offloading the flow to
hardware. Fix the following cases:

- nf_conn_act_ct_ext_fill() is called before extension is created with
nf_conn_act_ct_ext_add() in tcf_ct_act(). This can cause rule offload with
unspecified iifidx when connection is offloaded after only single
original-direction packet has been processed by tc data path. Always fill
the new nf_conn_act_ct_ext instance after creating it in
nf_conn_act_ct_ext_add().

- Offloading of unidirectional UDP NEW connections is now supported, but ct
flow iifidx field is not updated when connection is promoted to
bidirectional which can result reply-direction iifidx to be zero when
refreshing the connection. Fill in the extension and update flow iifidx
before calling flow_offload_refresh().

Fixes: 9795ded7f924 ("net/sched: act_ct: Fill offloading tuple iifidx")
Reviewed-by: Paul Blakey 
Signed-off-by: Vlad Buslov 
Reviewed-by: Simon Horman 
Fixes: 6a9bad0069cf ("net/sched: act_ct: offload UDP NEW connections")
Link: https://lore.kernel.org/r/20231103151410.764271-1-vladbu@nvidia.com
Signed-off-by: Jakub Kicinski

net: openvswitch: Annotate struct mask_array with __counted_by

2023-10-17T11:56:03+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

Signed-off-by: Christophe JAILLET 
Reviewed-by: Kees Cook 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/ca5c8049f58bb933f231afd0816e30a5aaa0eddd.1697264974.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Paolo Abeni

net: openvswitch: Use struct_size()

2023-10-17T11:56:03+00:00

Use struct_size() instead of hand writing it.
This is less verbose and more robust.

Signed-off-by: Christophe JAILLET 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/e5122b4ff878cbf3ed72653a395ad5c4da04dc1e.1697264974.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Paolo Abeni

net: openvswitch: Annotate struct dp_meter with __counted_by

2023-10-02T18:24:55+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct dp_meter.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Pravin B Shelar 
Cc: dev@openvswitch.org
Signed-off-by: Kees Cook 
Reviewed-by: Gustavo A. R. Silva 
Link: https://lore.kernel.org/r/20230922172858.3822653-12-keescook@chromium.org
Signed-off-by: Jakub Kicinski

net: openvswitch: Annotate struct dp_meter_instance with __counted_by

2023-10-02T18:24:54+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct dp_meter_instance.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Pravin B Shelar 
Cc: dev@openvswitch.org
Signed-off-by: Kees Cook 
Reviewed-by: Gustavo A. R. Silva 
Link: https://lore.kernel.org/r/20230922172858.3822653-10-keescook@chromium.org
Signed-off-by: Jakub Kicinski

openvswitch: reduce stack usage in do_execute_actions

2023-10-01T18:07:22+00:00

do_execute_actions() function can be called recursively multiple
times while executing actions that require pipeline forking or
recirculations.  It may also be re-entered multiple times if the packet
leaves openvswitch module and re-enters it through a different port.

Currently, there is a 256-byte array allocated on stack in this
function that is supposed to hold NSH header.  Compilers tend to
pre-allocate that space right at the beginning of the function:

     a88:       48 81 ec b0 01 00 00    sub    $0x1b0,%rsp

NSH is not a very common protocol, but the space is allocated on every
recursive call or re-entry multiplying the wasted stack space.

Move the stack allocation to push_nsh() function that is only used
if NSH actions are actually present.  push_nsh() is also a simple
function without a possibility for re-entry, so the stack is returned
right away.

With this change the preallocated space is reduced by 256 B per call:

     b18:       48 81 ec b0 00 00 00    sub    $0xb0,%rsp

Signed-off-by: Ilya Maximets 
Reviewed-by: Eric Dumazet 
Reviewed-by: Eelco Chaudron echaudro@redhat.com
Reviewed-by: Aaron Conole 
Signed-off-by: David S. Miller