14 Commits

Author SHA1 Message Date
Matt Johnston
f62457df5c mctp: Avoid warning if unregister notifies twice
Previously if an unregister notify handler ran twice (waiting for
netdev to be released) it would print a warning in mctp_unregister()
every subsequent time the unregister notify occured.

Instead we only need to worry about the case where a mctp_ptr is
set on an unknown device type.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-25 22:23:23 -08:00
Matt Johnston
8d783197f0 mctp: Fix warnings reported by clang-analyzer
net/mctp/device.c:140:11: warning: Assigned value is garbage or undefined
[clang-analyzer-core.uninitialized.Assign]
        mcb->idx = idx;

- Not a real problem due to how the callback runs, fix the warning.

net/mctp/route.c:458:4: warning: Value stored to 'msk' is never read
[clang-analyzer-deadcode.DeadStores]
        msk = container_of(key->sk, struct mctp_sock, sk);

- 'msk' dead assignment can be removed here.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-23 12:31:39 +00:00
Matt Johnston
dc121c0084 mctp: make __mctp_dev_get() take a refcount hold
Previously there was a race that could allow the mctp_dev refcount
to hit zero:

rcu_read_lock();
mdev = __mctp_dev_get(dev);
// mctp_unregister() happens here, mdev->refs hits zero
mctp_dev_hold(dev);
rcu_read_unlock();

Now we make __mctp_dev_get() take the hold itself. It is safe to test
against the zero refcount because __mctp_dev_get() is called holding
rcu_read_lock and mctp_dev uses kfree_rcu().

Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-23 12:29:15 +00:00
Jeremy Kerr
cb196b7259 mctp: replace mctp_address_ok with more fine-grained helpers
Currently, we have mctp_address_ok(), which checks if an EID is in the
"valid" range of 8-254 inclusive. However, 0 and 255 may also be valid
addresses, depending on context. 0 is the NULL EID, which may be set
when physical addressing is used. 255 is valid as a destination address
for broadcasts.

This change renames mctp_address_ok to mctp_address_unicast, and adds
similar helpers for broadcast and null EIDs, which will be used in an
upcoming commit.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-18 21:24:28 -08:00
Jakub Kicinski
c78b8b20e3 net: don't include ndisc.h from ipv6.h
Nothing in ipv6.h needs ndisc.h, drop it.

Link: https://lore.kernel.org/r/20220203043457.2222388-1-kuba@kernel.org
Acked-by: Jeremy Kerr <jk@codeconstruct.com.au>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Link: https://lore.kernel.org/r/20220203231240.2297588-1-kuba@kernel.org
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-04 14:15:11 -08:00
Matt Johnston
dbcefdeb2a mctp: emit RTM_NEWADDR and RTM_DELADDR
Userspace can receive notification of MCTP address changes via
RTNLGRP_MCTP_IFADDR rtnetlink multicast group.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20211220023104.1965509-1-matt@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-20 18:40:48 -08:00
Jeremy Kerr
67737c4572 mctp: Pass flow data & flow release events to drivers
Now that we have an extension for MCTP data in skbs, populate the flow
when a key has been created for the packet, and add a device driver
operation to inform of flow destruction.

Includes a fix for a warning with test builds:
Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-29 13:23:51 +01:00
Matt Johnston
7b1871af75 mctp: Warn if pointer is set for a wrong dev type
Should not occur but is a sanity check.

May help tracking down Trinity reported issue
https://lore.kernel.org/lkml/20210913030701.GA5926@xsang-OptiPlex-9020/

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:12 +01:00
Jeremy Kerr
43f55f23f7 mctp: Add refcounts to mctp_dev
Currently, we tie the struct mctp_dev lifetime to the underlying struct
net_device, and hold/put that device as a proxy for a separate mctp_dev
refcount. This works because we're not holding any references to the
mctp_dev that are different from the netdev lifetime.

In a future change we'll break that assumption though, as we'll need to
hold mctp_dev references in a workqueue, which might live past the
netdev unregister notification.

In order to support that, this change introduces a refcount on the
mctp_dev, currently taken by the net_device->mctp_ptr reference, and
released on netdev unregister events. We can then use this for future
references that might outlast the net device.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Matt Johnston
f364dd71d9 mctp: Allow MCTP on tun devices
Allowing TUN is useful for testing, to route packets to userspace or to
tunnel between machines.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:00:11 +01:00
Matt Johnston
03f2bbc4ee mctp: Allow per-netns default networks
Currently we have a compile-time default network
(MCTP_INITIAL_DEFAULT_NET). This change introduces a default_net field
on the net namespace, allowing future configuration for new interfaces.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Matt Johnston
4d8b931928 mctp: Add neighbour implementation
Add an initial neighbour table implementation, to be used in the route
output path.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
889b7da23a mctp: Add initial routing framework
Add a simple routing table, and a couple of route output handlers, and
the mctp packet_type & handler.

Includes changes from Matt Johnston <matt@codeconstruct.com.au>.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
583be982d9 mctp: Add device handling and netlink interface
This change adds the infrastructure for managing MCTP netdevices; we add
a pointer to the AF_MCTP-specific data to struct netdevice, and hook up
the rtnetlink operations for adding and removing addresses.

Includes changes from Matt Johnston <matt@codeconstruct.com.au>.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00