To capture TX packets during a test, we are currently intercepting the
dst->output with an implementation that adds the transmitted packet to
a skb queue attached to the test-specific mock dst. The netdev itself is
not involved in the test TX path.
Instead, we can just use our test device to stash TXed packets for later
inspection by the test. This means we can include the actual
mctp_dst_output() implementation in the test (by setting dst.output in
the test case), and don't need to be creating fake dst objects, or their
corresponding skb queues.
We need to ensure that the netdev is up to allow delivery to
ndo_start_xmit, but the tests assume active devices at present anyway.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20251126-dev-mctp-test-tx-queue-v2-1-4e5bbd1d6c57@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On transmit, we are currently relying on skb->dev being set by
mctp_local_output() when we first set up the skb destination fields.
However, forwarded skbs do not use the local_output path, so will retain
their incoming netdev as their ->dev on tx. This does not work when
we're forwarding between interfaces.
Set skb->dev unconditionally in the transmit path, to allow for proper
forwarding.
We keep the skb->dev initialisation in mctp_local_output(), as we use it
for fragmentation.
Fixes: 269936db5e ("net: mctp: separate routing database from routing operations")
Suggested-by: Vince Chang <vince_chang@aspeedtech.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20251125-dev-forward-v1-1-54ecffcd0616@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Update all struct proto_ops connect() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Update all struct proto_ops bind() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-2-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In mctp_getsockopt(), unrecognized options currently return -EINVAL.
In contrast, mctp_setsockopt() returns -ENOPROTOOPT for unknown
options.
Update mctp_getsockopt() to also return -ENOPROTOOPT for unknown
options. This aligns the behavior of getsockopt() and setsockopt(),
and matches the standard kernel socket API convention for handling
unsupported options.
Fixes: 99ce45d5e7 ("mctp: Implement extended addressing")
Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Link: https://patch.msgid.link/20250902102059.1370008-1-alok.a.tiwari@oracle.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Prior to calling bind() a program may call connect() on a socket to
restrict to a remote peer address.
Using connect() is the normal mechanism to specify a remote network
peer, so we use that here. In MCTP connect() is only used for bound
sockets - send() is not available for MCTP since a tag must be provided
for each message.
The smctp_type must match between connect() and bind() calls.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Link: https://patch.msgid.link/20250710-mctp-bind-v4-6-8ec2f6460c56@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When a specific EID is passed as a bind address, it only makes sense to
interpret with an actual network ID, so resolve that to the default
network at bind time.
For bind address of MCTP_ADDR_ANY, we want to be able to capture traffic
to any network and address, so keep the current behaviour of matching
traffic from any network interface (don't interpret MCTP_NET_ANY as
the default network ID).
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Link: https://patch.msgid.link/20250710-mctp-bind-v4-3-8ec2f6460c56@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Disallow bind() calls that have the same arguments as existing bound
sockets. Previously multiple sockets could bind() to the same
type/local address, with an arbitrary socket receiving matched messages.
This is only a partial fix, a future commit will define precedence order
for MCTP_ADDR_ANY versus specific EID bind(), which are allowed to exist
together.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Link: https://patch.msgid.link/20250710-mctp-bind-v4-2-8ec2f6460c56@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This change allows for gateway routing, where a route table entry
may reference a routable endpoint (by network and EID), instead of
routing directly to a netdevice.
We add support for a RTM_GATEWAY attribute for netlink route updates,
with an attribute format of:
struct mctp_fq_addr {
unsigned int net;
mctp_eid_t eid;
}
- we need the net here to uniquely identify the target EID, as we no
longer have the device reference directly (which would provide the net
id in the case of direct routes).
This makes route lookups recursive, as a route lookup that returns a
gateway route must be resolved into a direct route (ie, to a device)
eventually. We provide a limit to the route lookups, to prevent infinite
loop routing.
The route lookup populates a new 'nexthop' field in the dst structure,
which now specifies the key for the neighbour table lookup on device
output, rather than using the packet destination address directly.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20250702-dev-forwarding-v5-13-1468191da8a4@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The netlink route parsing functions end up setting a bunch of output
variables from the rt attributes. This will get messy when the routes
become more complex.
So, split the rt parsing into two types: a lookup (returning route
target data suitable for a route lookup, like when deleting a route) and
a populate (setting fields of a struct mctp_route).
In doing this, we need to separate the route allocation from
mctp_route_add, so add some comments on the lifetime semantics for the
latter.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20250702-dev-forwarding-v5-12-1468191da8a4@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This change adds a struct mctp_dst, representing the result of a routing
lookup. This decouples the struct mctp_route from the actual
implementation of a routing operation.
This will allow for future routing changes which may require more
involved lookup logic, such as gateway routing - which may require
multiple traversals of the routing table.
Since we only use the struct mctp_route at lookup time, we no longer
hold routes over a routing operation, as we only need it to populate the
dst. However, we do hold the dev while the dst is active.
This requires some changes to the route test infrastructure, as we no
longer have a mock route to handle the route output operation, and
transient dsts are created by the routing code, so we can't override
them as easily.
Instead, we use kunit->priv to stash a packet queue, and a custom
dst_output function queues into that packet queue, which we can use for
later expectations.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20250702-dev-forwarding-v5-3-1468191da8a4@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
In our input_cloned_frag test, we currently allocate our test buffers
arbitrarily-sized at 100 bytes.
We only expect to receive a max of 15 bytes from the socket, so reduce
to a more appropriate size. There are some upcoming changes to the
routing code which hit a frame-size limit on s390, so reduce the usage
before that lands.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20250702-dev-forwarding-v5-2-1468191da8a4@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Jakub suggests:
> I have a different request :) Matt, once this ends up in net-next
> (end of this week) could you refactor it to use nlmsg_payload() ?
> It doesn't exist in net but this is exactly why it was added.
This refactors the additions to both mctp_dump_addrinfo(), and
mctp_rtm_getneigh() - two cases where we're calling nlh_data() on an
an incoming netlink message, without a prior nlmsg_parse().
For the neigh.c case, we cannot hit the failure where the nlh does not
contain a full ndmsg at present, as the core handler
(net/core/neighbour.c, neigh_get()) has already validated the size
through neigh_valid_req_get(), and would have failed the get operation
before the MCTP hander is called.
However, relying on that is a bit fragile, so apply the nlmsg_payload
refector here too.
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20250521-mctp-nlmsg-payload-v2-1-e85df160c405@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
mctp_flow_prepare_output() is called in mctp_route_output(), which
places outbound packets onto a given interface. The packet may represent
a message fragment, in which case we provoke an unbalanced reference
count to the underlying device. This causes trouble if we ever attempt
to remove the interface:
[ 48.702195] usb 1-1: USB disconnect, device number 2
[ 58.883056] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2
[ 69.022548] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2
[ 79.172568] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2
...
Predicate the invocation of mctp_dev_set_key() in
mctp_flow_prepare_output() on not already having associated the device
with the key. It's not yet realistic to uphold the property that the key
maintains only one device reference earlier in the transmission sequence
as the route (and therefore the device) may not be known at the time the
key is associated with the socket.
Fixes: 67737c4572 ("mctp: Pass flow data & flow release events to drivers")
Acked-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>
Link: https://patch.msgid.link/20250508-mctp-dev-refcount-v1-1-d4f965c67bb5@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.
Conversion was done with coccinelle plus manual fixups where necessary.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ensure that the frag_list used for reassembly isn't shared with other
packets. This avoids incorrect reassembly when packets are cloned, and
prevents a memory leak due to circular references between fragments and
their skb_shared_info.
The upcoming MCTP-over-USB driver uses skb_clone which can trigger the
problem - other MCTP drivers don't share SKBs.
A kunit test is added to reproduce the issue.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Fixes: 4a992bbd36 ("mctp: Implement message fragmentation & reassembly")
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250306-matt-mctp-usb-v1-1-085502b3dd28@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Currently, we don't use the return value from sock_queue_rcv_skb, which
means we may leak skbs if a message is not successfully queued to a
socket.
Instead, ensure that we're freeing the skb where the sock hasn't
otherwise taken ownership of the skb by adding checks on the
sock_queue_rcv_skb() to invoke a kfree on failure.
In doing so, rather than using the 'rc' value to trigger the
kfree_skb(), use the skb pointer itself, which is more explicit.
Also, add a kunit test for the sock delivery failure cases.
Fixes: 4a992bbd36 ("mctp: Implement message fragmentation & reassembly")
Cc: stable@vger.kernel.org
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20241218-mctp-next-v2-1-1c1729645eaa@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
MCTP control protocol implementations are transport binding dependent.
Endpoint discovery is mandatory based on transport binding.
Message timing requirements are specified in each respective transport
binding specification.
However, we currently have no means to get this information from MCTP
links.
Add a IFLA_MCTP_PHYS_BINDING netlink link attribute, which represents
the transport type using the DMTF DSP0239-defined type numbers, returned
as part of RTM_GETLINK data.
We get an IFLA_MCTP_PHYS_BINDING attribute for each MCTP link, for
example:
- 0x00 (unspec) for loopback interface;
- 0x01 (SMBus/I2C) for mctpi2c%d interfaces; and
- 0x05 (serial) for mctpserial%d interfaces.
Signed-off-by: Khang Nguyen <khangng@os.amperecomputing.com>
Reviewed-by: Matt Johnston <matt@codeconstruct.com.au>
Link: https://patch.msgid.link/20241105071915.821871-1-khangng@os.amperecomputing.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The next patch will add init_srcu_struct() in rtnl_af_register(),
then we need to handle its error.
Let's add the error handling in advance to make the following
patch cleaner.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Since introduced, mctp has been ignoring the returned value of
rtnl_register_module(), which could fail silently.
Handling the error allows users to view a module as an all-or-nothing
thing in terms of the rtnetlink functionality. This prevents syzkaller
from reporting spurious errors from its tests, where OOM often occurs
and module is automatically loaded.
Let's handle the errors by rtnl_register_many().
Fixes: 583be982d9 ("mctp: Add device handling and netlink interface")
Fixes: 831119f887 ("mctp: Add neighbour netlink interface")
Fixes: 06d2f4c583 ("mctp: Add netlink route management")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Currently, mctp_local_output only takes ownership of skb on success, and
we may leak an skb if mctp_local_output fails in specific states; the
skb ownership isn't transferred until the actual output routing occurs.
Instead, make mctp_local_output free the skb on all error paths up to
the route action, so it always consumes the passed skb.
Fixes: 833ef3b91d ("mctp: Populate socket implementation")
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240220081053.1439104-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Ensure we have the correct key parameters on sending a message.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
