31 Mar, 2020
12 commits
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Signed-off-by: David S. Miller
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Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-nextThe following patchset contains Netfilter/IPVS updates for net-next:
1) Add support to specify a stateful expression in set definitions,
this allows users to specify e.g. counters per set elements.2) Flowtable software counter support.
3) Flowtable hardware offload counter support, from wenxu.
3) Parallelize flowtable hardware offload requests, from Paul Blakey.
This includes a patch to add one work entry per offload command.4) Several patches to rework nf_queue refcount handling, from Florian
Westphal.4) A few fixes for the flowtable tunnel offload: Fix crash if tunneling
information is missing and set up indirect flow block as TC_SETUP_FT,
patch from wenxu.5) Stricter netlink attribute sanity check on filters, from Romain Bellan
and Florent Fourcot.5) Annotations to make sparse happy, from Jules Irenge.
6) Improve icmp errors in debugging information, from Haishuang Yan.
7) Fix warning in IPVS icmp error debugging, from Haishuang Yan.
8) Fix endianess issue in tcp extension header, from Sergey Marinkevich.
====================Signed-off-by: David S. Miller
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The previous patch allowed device drivers to publish their default
binding between packet trap policers and packet trap groups. However,
some users might not be content with this binding and would like to
change it.In case user space passed a packet trap policer identifier when setting
a packet trap group, invoke the appropriate device driver callback and
pass the new policer identifier.v2:
* Check for presence of 'DEVLINK_ATTR_TRAP_POLICER_ID' in
devlink_trap_group_set() and bail if not present
* Add extack error message in case trap group was partially modifiedSigned-off-by: Ido Schimmel
Reviewed-by: Jiri Pirko
Acked-by: Jakub Kicinski
Signed-off-by: David S. Miller -
Packet trap groups are used to aggregate logically related packet traps.
Currently, these groups allow user space to batch operations such as
setting the trap action of all member traps.In order to prevent the CPU from being overwhelmed by too many trapped
packets, it is desirable to bind a packet trap policer to these groups.
For example, to limit all the packets that encountered an exception
during routing to 10Kpps.Allow device drivers to bind default packet trap policers to packet trap
groups when the latter are registered with devlink.The next patch will enable user space to change this default binding.
Signed-off-by: Ido Schimmel
Reviewed-by: Jiri Pirko
Reviewed-by: Jakub Kicinski
Signed-off-by: David S. Miller -
Devices capable of offloading the kernel's datapath and perform
functions such as bridging and routing must also be able to send (trap)
specific packets to the kernel (i.e., the CPU) for processing.For example, a device acting as a multicast-aware bridge must be able to
trap IGMP membership reports to the kernel for processing by the bridge
module.In most cases, the underlying device is capable of handling packet rates
that are several orders of magnitude higher compared to those that can
be handled by the CPU.Therefore, in order to prevent the underlying device from overwhelming
the CPU, devices usually include packet trap policers that are able to
police the trapped packets to rates that can be handled by the CPU.This patch allows capable device drivers to register their supported
packet trap policers with devlink. User space can then tune the
parameters of these policer (currently, rate and burst size) and read
from the device the number of packets that were dropped by the policer,
if supported.Subsequent patches in the series will allow device drivers to create
default binding between these policers and packet trap groups and allow
user space to change the binding.v2:
* Add 'strict_start_type' in devlink policy
* Have device drivers provide max/min rate/burst size for each policer.
Use them to check validity of user provided parametersSigned-off-by: Ido Schimmel
Reviewed-by: Jiri Pirko
Reviewed-by: Jakub Kicinski
Signed-off-by: David S. Miller -
Avoid taking a reference on listen sockets by checking the socket type
in the sk_assign and in the corresponding skb_steal_sock() code in the
the transport layer, and by ensuring that the prefetch free (sock_pfree)
function uses the same logic to check whether the socket is refcounted.Suggested-by: Martin KaFai Lau
Signed-off-by: Joe Stringer
Signed-off-by: Alexei Starovoitov
Acked-by: Martin KaFai Lau
Link: https://lore.kernel.org/bpf/20200329225342.16317-4-joe@wand.net.nz -
Add support for TPROXY via a new bpf helper, bpf_sk_assign().
This helper requires the BPF program to discover the socket via a call
to bpf_sk*_lookup_*(), then pass this socket to the new helper. The
helper takes its own reference to the socket in addition to any existing
reference that may or may not currently be obtained for the duration of
BPF processing. For the destination socket to receive the traffic, the
traffic must be routed towards that socket via local route. The
simplest example route is below, but in practice you may want to route
traffic more narrowly (eg by CIDR):$ ip route add local default dev lo
This patch avoids trying to introduce an extra bit into the skb->sk, as
that would require more invasive changes to all code interacting with
the socket to ensure that the bit is handled correctly, such as all
error-handling cases along the path from the helper in BPF through to
the orphan path in the input. Instead, we opt to use the destructor
variable to switch on the prefetch of the socket.Signed-off-by: Joe Stringer
Signed-off-by: Alexei Starovoitov
Acked-by: Martin KaFai Lau
Link: https://lore.kernel.org/bpf/20200329225342.16317-2-joe@wand.net.nz -
On low memory system, run time dumps can consume too much memory. Add
administrator ability to disable auto dumps per reporter as part of the
error flow handle routine.This attribute is not relevant while executing
DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET.By default, auto dump is activated for any reporter that has a dump method,
as part of the reporter registration to devlink.Signed-off-by: Eran Ben Elisha
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
When health reporter is registered to devlink, devlink will implicitly set
auto recover if and only if the reporter has a recover method. No reason
to explicitly get the auto recover flag from the driver.Remove this flag from all drivers that called
devlink_health_reporter_create.All existing health reporters set auto recovery to true if they have a
recover method.Yet, administrator can unset auto recover via netlink command as prior to
this patch.Signed-off-by: Eran Ben Elisha
Reviewed-by: Jiri Pirko
Reviewed-by: Jakub Kicinski
Signed-off-by: David S. Miller -
The rest of the devlink code sets the extack message using
NL_SET_ERR_MSG_MOD. Change the existing appearances of NL_SET_ERR_MSG
to NL_SET_ERR_MSG_MOD.Signed-off-by: Jiri Pirko
Signed-off-by: David S. Miller -
Xin Long says:
On udp rx path udp_rcv_segment() may do segment where the frag skbs
will get the header copied from the head skb in skb_segment_list()
by calling __copy_skb_header(), which could overwrite the frag skbs'
extensions by __skb_ext_copy() and cause a leak.This issue was found after loading esp_offload where a sec path ext
is set in the skb.Fix this by discarding head state of the fraglist skb before replacing
its contents.Fixes: 3a1296a38d0cf62 ("net: Support GRO/GSO fraglist chaining.")
Cc: Steffen Klassert
Reported-by: Xiumei Mu
Tested-by: Xin Long
Signed-off-by: Florian Westphal
Acked-by: Steffen Klassert
Signed-off-by: David S. Miller
30 Mar, 2020
5 commits
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Add three string sets related to timestamping information:
ETH_SS_SOF_TIMESTAMPING: SOF_TIMESTAMPING_* flags
ETH_SS_TS_TX_TYPES: timestamping Tx types
ETH_SS_TS_RX_FILTERS: timestamping Rx filtersThese will be used for TIMESTAMP_GET request.
v2: avoid compiler warning ("enumeration value not handled in switch")
in net_hwtstamp_validate()v3: omit dash in Tx type names ("one-step-*" -> "onestep-*"), suggested by
Richard CochranSigned-off-by: Michal Kubecek
Acked-by: Richard Cochran
Signed-off-by: David S. Miller -
This patch adds functionality to configure routes for RPL source routing
functionality. There is no IPIP functionality yet implemented which can
be added later when the cases when to use IPv6 encapuslation comes more
clear.Signed-off-by: Alexander Aring
Signed-off-by: David S. Miller -
The build_state callback of lwtunnel doesn't contain the net namespace
structure yet. This patch will add it so we can check on specific
address configuration at creation time of rpl source routes.Signed-off-by: Alexander Aring
Signed-off-by: David S. Miller -
The SKB_SGO_CB_OFFSET should be SKB_GSO_CB_OFFSET which means the
offset of the GSO in skb cb. This patch fixes the typo.Fixes: 9207f9d45b0a ("net: preserve IP control block during GSO segmentation")
Signed-off-by: Cambda Zhu
Signed-off-by: David S. Miller -
page pool API can be useful for non-DMA cases like
xen-netfront driver so let's allow to pass zero flags to
page pool flags.v2: check DMA direction only if PP_FLAG_DMA_MAP is set
Signed-off-by: Denis Kirjanov
Acked-by: Jesper Dangaard Brouer
Signed-off-by: David S. Miller
29 Mar, 2020
1 commit
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While it is currently possible for userspace to specify that an existing
XDP program should not be replaced when attaching to an interface, there is
no mechanism to safely replace a specific XDP program with another.This patch adds a new netlink attribute, IFLA_XDP_EXPECTED_FD, which can be
set along with IFLA_XDP_FD. If set, the kernel will check that the program
currently loaded on the interface matches the expected one, and fail the
operation if it does not. This corresponds to a 'cmpxchg' memory operation.
Setting the new attribute with a negative value means that no program is
expected to be attached, which corresponds to setting the UPDATE_IF_NOEXIST
flag.A new companion flag, XDP_FLAGS_REPLACE, is also added to explicitly
request checking of the EXPECTED_FD attribute. This is needed for userspace
to discover whether the kernel supports the new attribute.Signed-off-by: Toke Høiland-Jørgensen
Signed-off-by: Alexei Starovoitov
Reviewed-by: Jakub Kicinski
Link: https://lore.kernel.org/bpf/158515700640.92963.3551295145441017022.stgit@toke.dk
28 Mar, 2020
7 commits
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We already have the bpf_get_current_uid_gid() helper enabled, and
given we now have perf event RB output available for connect(),
sendmsg(), recvmsg() and bind-related hooks, add a trivial change
to enable bpf_get_current_pid_tgid() and bpf_get_current_comm()
as well.Signed-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov
Acked-by: Andrii Nakryiko
Link: https://lore.kernel.org/bpf/18744744ed93c06343be8b41edcfd858706f39d7.1585323121.git.daniel@iogearbox.net -
Enable the bpf_get_current_cgroup_id() helper for connect(), sendmsg(),
recvmsg() and bind-related hooks in order to retrieve the cgroup v2
context which can then be used as part of the key for BPF map lookups,
for example. Given these hooks operate in process context 'current' is
always valid and pointing to the app that is performing mentioned
syscalls if it's subject to a v2 cgroup. Also with same motivation of
commit 7723628101aa ("bpf: Introduce bpf_skb_ancestor_cgroup_id helper")
enable retrieval of ancestor from current so the cgroup id can be used
for policy lookups which can then forbid connect() / bind(), for example.Signed-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov
Link: https://lore.kernel.org/bpf/d2a7ef42530ad299e3cbb245e6c12374b72145ef.1585323121.git.daniel@iogearbox.net -
Today, Kubernetes is still operating on cgroups v1, however, it is
possible to retrieve the task's classid based on 'current' out of
connect(), sendmsg(), recvmsg() and bind-related hooks for orchestrators
which attach to the root cgroup v2 hook in a mixed env like in case
of Cilium, for example, in order to then correlate certain pod traffic
and use it as part of the key for BPF map lookups.Signed-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov
Link: https://lore.kernel.org/bpf/555e1c69db7376c0947007b4951c260e1074efc3.1585323121.git.daniel@iogearbox.net -
In Cilium we're mainly using BPF cgroup hooks today in order to implement
kube-proxy free Kubernetes service translation for ClusterIP, NodePort (*),
ExternalIP, and LoadBalancer as well as HostPort mapping [0] for all traffic
between Cilium managed nodes. While this works in its current shape and avoids
packet-level NAT for inter Cilium managed node traffic, there is one major
limitation we're facing today, that is, lack of netns awareness.In Kubernetes, the concept of Pods (which hold one or multiple containers)
has been built around network namespaces, so while we can use the global scope
of attaching to root BPF cgroup hooks also to our advantage (e.g. for exposing
NodePort ports on loopback addresses), we also have the need to differentiate
between initial network namespaces and non-initial one. For example, ExternalIP
services mandate that non-local service IPs are not to be translated from the
host (initial) network namespace as one example. Right now, we have an ugly
work-around in place where non-local service IPs for ExternalIP services are
not xlated from connect() and friends BPF hooks but instead via less efficient
packet-level NAT on the veth tc ingress hook for Pod traffic.On top of determining whether we're in initial or non-initial network namespace
we also have a need for a socket-cookie like mechanism for network namespaces
scope. Socket cookies have the nice property that they can be combined as part
of the key structure e.g. for BPF LRU maps without having to worry that the
cookie could be recycled. We are planning to use this for our sessionAffinity
implementation for services. Therefore, add a new bpf_get_netns_cookie() helper
which would resolve both use cases at once: bpf_get_netns_cookie(NULL) would
provide the cookie for the initial network namespace while passing the context
instead of NULL would provide the cookie from the application's network namespace.
We're using a hole, so no size increase; the assignment happens only once.
Therefore this allows for a comparison on initial namespace as well as regular
cookie usage as we have today with socket cookies. We could later on enable
this helper for other program types as well as we would see need.(*) Both externalTrafficPolicy={Local|Cluster} types
[0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.cSigned-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov
Link: https://lore.kernel.org/bpf/c47d2346982693a9cf9da0e12690453aded4c788.1585323121.git.daniel@iogearbox.net -
Currently, connect(), sendmsg(), recvmsg() and bind-related hooks
are all lacking perf event rb output in order to push notifications
or monitoring events up to user space. Back in commit a5a3a828cd00
("bpf: add perf event notificaton support for sock_ops"), I've worked
with Sowmini to enable them for sock_ops where the context part is
not used (as opposed to skbs for example where the packet data can
be appended). Make the bpf_sockopt_event_output() helper generic and
enable it for mentioned hooks.Signed-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov
Link: https://lore.kernel.org/bpf/69c39daf87e076b31e52473c902e9bfd37559124.1585323121.git.daniel@iogearbox.net -
We currently make heavy use of the socket cookie in BPF's connect(),
sendmsg() and recvmsg() hooks for load-balancing decisions. However,
it is currently not enabled/implemented in BPF {post-}bind hooks
where it can later be used in combination for correlation in the tc
egress path, for example.Signed-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov
Link: https://lore.kernel.org/bpf/e9d71f310715332f12d238cc650c1edc5be55119.1585323121.git.daniel@iogearbox.net -
The indirect block setup should use TC_SETUP_FT as the type instead of
TC_SETUP_BLOCK. Adjust existing users of the indirect flow block
infrastructure.Fixes: b5140a36da78 ("netfilter: flowtable: add indr block setup support")
Signed-off-by: wenxu
Signed-off-by: Pablo Neira Ayuso
27 Mar, 2020
10 commits
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Implement support for the DEVLINK_CMD_REGION_NEW command for creating
snapshots. This new command parallels the existing
DEVLINK_CMD_REGION_DEL.In order for DEVLINK_CMD_REGION_NEW to work for a region, the new
".snapshot" operation must be implemented in the region's ops structure.The desired snapshot id must be provided. This helps avoid confusion on
the purpose of DEVLINK_CMD_REGION_NEW, and keeps the API simpler.The requested id will be inserted into the xarray tracking the number of
snapshots using each id. If this id is already used by another snapshot
on any region, an error will be returned.Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
Each snapshot created for a devlink region must have an id. These ids
are supposed to be unique per "event" that caused the snapshot to be
created. Drivers call devlink_region_snapshot_id_get to obtain a new id
to use for a new event trigger. The id values are tracked per devlink,
so that the same id number can be used if a triggering event creates
multiple snapshots on different regions.There is no mechanism for snapshot ids to ever be reused. Introduce an
xarray to store the count of how many snapshots are using a given id,
replacing the snapshot_id field previously used for picking the next id.The devlink_region_snapshot_id_get() function will use xa_alloc to
insert an initial value of 1 value at an available slot between 0 and
U32_MAX.The new __devlink_snapshot_id_increment() and
__devlink_snapshot_id_decrement() functions will be used to track how
many snapshots currently use an id.Drivers must now call devlink_snapshot_id_put() in order to release
their reference of the snapshot id after adding region snapshots.By tracking the total number of snapshots using a given id, it is
possible for the decrement() function to erase the id from the xarray
when it is not in use.With this method, a snapshot id can become reused again once all
snapshots that referred to it have been deleted via
DEVLINK_CMD_REGION_DEL, and the driver has finished adding snapshots.This work also paves the way to introduce a mechanism for userspace to
request a snapshot.Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
The devlink_snapshot_id_get() function returns a snapshot id. The
snapshot id is a u32, so there is no way to indicate an error code.A future change is going to possibly add additional cases where this
function could fail. Refactor the function to return the snapshot id in
an argument, so that it can return zero or an error value.This ensures that snapshot ids cannot be confused with error values, and
aids in the future refactor of snapshot id allocation management.Because there is no current way to release previously used snapshot ids,
add a simple check ensuring that an error is reported in case the
snapshot_id would over flow.Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
A future change is going to implement a new devlink command to request
a snapshot on demand. As part of this, the logic for handling the
snapshot ids will be refactored. To simplify the snapshot id allocation
function, move it to a separate function prefixed by `__`. This helper
function will assume the lock is held.While no other callers will exist, it simplifies refactoring the logic
because there is no need to complicate the function with gotos to handle
unlocking on failure.Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
The devlink_region_snapshot_create function returns -ENOMEM when the
maximum number of snapshots has been reached. This is confusing because
it is not an issue of being out of memory. Change this to use -ENOSPC
instead.Reported-by: Jiri Pirko
Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
A future change is going to add a new devlink command to request
a snapshot on demand. This function will want to call the
devlink_region_snapshot_create function while already holding the
devlink instance lock.Extract the logic of this function into a static function prefixed by
`__` to indicate that it is an internal helper function. Modify the
original function to be implemented in terms of the new locked
function.Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Reviewed-by: Jakub Kicinski
Signed-off-by: David S. Miller -
The function documentation comment for devlink_region_snapshot_create
included a literal tab character between 'future analyses' that was
difficult to spot as it happened to only display as one space wide.Fix the comment to use a space here instead of a stray tab appearing in
the middle of a sentence.Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
It does not makes sense that two snapshots for a given region would use
different destructors. Simplify snapshot creation by adding
a .destructor op for regions.This operation will replace the data_destructor for the snapshot
creation, and makes snapshot creation easier.Noticed-by: Jakub Kicinski
Signed-off-by: Jacob Keller
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
Modify the devlink region code in preparation for adding new operations
on regions.Create a devlink_region_ops structure, and move the name pointer from
within the devlink_region structure into the ops structure (similar to
the devlink_health_reporter_ops).This prepares the regions to enable support of additional operations in
the future such as requesting snapshots, or accessing the region
directly without a snapshot.In order to re-use the constant strings in the mlx4 driver their
declaration must be changed to 'const char * const' to ensure the
compiler realizes that both the data and the pointer cannot change.Signed-off-by: Jacob Keller
Reviewed-by: Jakub Kicinski
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller -
Saeed Mahameed says:
====================
mlx5-updates-2020-03-251) Cleanups from Dan Carpenter and wenxu.
2) Paul and Roi, Some minor updates and fixes to E-Switch to address
issues introduced in the previous reg_c0 updates series.3) Eli Cohen simplifies and improves flow steering matching group searches
and flow table entries version management.4) Parav Pandit, improves devlink eswitch mode changes thread safety.
By making devlink rely on driver for thread safety and introducing mlx5
eswitch mode change protection.
====================Signed-off-by: David S. Miller
26 Mar, 2020
4 commits
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devlink_nl_cmd_eswitch_set_doit() doesn't hold devlink->lock mutex while
invoking driver callback. This is likely due to eswitch mode setting
involves adding/remove devlink ports, health reporters or
other devlink objects for a devlink device.So it is driver responsiblity to ensure thread safe eswitch state
transition happening via either sriov legacy enablement or via devlink
eswitch set callback.Therefore, get() callback should also be invoked without holding
devlink->lock mutex.
Vendor driver can use same internal lock which it uses during eswitch
mode set() callback.
This makes get() and set() implimentation symmetric in devlink core and
in vendor drivers.Hence, remove holding devlink->lock mutex during eswitch get() callback.
Failing to do so results into below deadlock scenario when mlx5_core
driver is improved to handle eswitch mode set critical section invoked
by devlink and sriov sysfs interface in subsequent patch.devlink_nl_cmd_eswitch_set_doit()
mlx5_eswitch_mode_set()
mutex_lock(esw->mode_lock) lock); lock); mode_lock)
Reviewed-by: Mark Bloch
Signed-off-by: Parav Pandit
Signed-off-by: Saeed Mahameed -
Overlapping header include additions in macsec.c
A bug fix in 'net' overlapping with the removal of 'version'
string in ena_netdev.cOverlapping test additions in selftests Makefile
Overlapping PCI ID table adjustments in iwlwifi driver.
Signed-off-by: David S. Miller
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net/netfilter/nft_fwd_netdev.c: In function ‘nft_fwd_netdev_eval’:
net/netfilter/nft_fwd_netdev.c:32:10: error: ‘struct sk_buff’ has no member named ‘tc_redirected’
pkt->skb->tc_redirected = 1;
^~
net/netfilter/nft_fwd_netdev.c:33:10: error: ‘struct sk_buff’ has no member named ‘tc_from_ingress’
pkt->skb->tc_from_ingress = 1;
^~To avoid a direct dependency with tc actions from netfilter, wrap the
redirect bits around CONFIG_NET_REDIRECT and move helpers to
include/linux/skbuff.h. Turn on this toggle from the ifb driver, the
only existing client of these bits in the tree.This patch adds skb_set_redirected() that sets on the redirected bit
on the skbuff, it specifies if the packet was redirect from ingress
and resets the timestamp (timestamp reset was originally missing in the
netfilter bugfix).Fixes: bcfabee1afd99484 ("netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress")
Reported-by: noreply@ellerman.id.au
Reported-by: Geert Uytterhoeven
Signed-off-by: Pablo Neira Ayuso
Signed-off-by: David S. Miller -
TCP recvmsg() calls skb_copy_datagram_iter(), which
calls an indirect function (cb pointing to simple_copy_to_iter())
for every MSS (fragment) present in the skb.CONFIG_RETPOLINE=y forces a very expensive operation
that we can avoid thanks to indirect call wrappers.This patch gives a 13% increase of performance on
a single flow, if the bottleneck is the thread reading
the TCP socket.Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers")
Signed-off-by: Eric Dumazet
Acked-by: Paolo Abeni
Acked-by: Willem de Bruijn
Signed-off-by: David S. Miller
24 Mar, 2020
1 commit
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Packet trap groups are now explicitly registered by drivers and not
implicitly registered when the packet traps are registered. Therefore,
there is no need to encode entire group structure the trap is associated
with inside the trap structure.Instead, only pass the group identifier. Refer to it as initial group
identifier, as future patches will allow user space to move traps
between groups.Signed-off-by: Ido Schimmel
Reviewed-by: Jiri Pirko
Signed-off-by: David S. Miller