Commit Graph

22 Commits

Author SHA1 Message Date
Jeremy Kerr
6c52b12159 mctp: perform route lookups under a RCU read-side lock
[ Upstream commit 5093bbfc10 ]

Our current route lookups (mctp_route_lookup and mctp_route_lookup_null)
traverse the net's route list without the RCU read lock held. This means
the route lookup is subject to preemption, resulting in an potential
grace period expiry, and so an eventual kfree() while we still have the
route pointer.

Add the proper read-side critical section locks around the route
lookups, preventing premption and a possible parallel kfree.

The remaining net->mctp.routes accesses are already under a
rcu_read_lock, or protected by the RTNL for updates.

Based on an analysis from Sili Luo <rootlab@huawei.com>, where
introducing a delay in the route lookup could cause a UAF on
simultaneous sendmsg() and route deletion.

Reported-by: Sili Luo <rootlab@huawei.com>
Fixes: 889b7da23a ("mctp: Add initial routing framework")
Cc: stable@vger.kernel.org
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/29c4b0e67dc1bf3571df3982de87df90cae9b631.1696837310.git.jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25 11:58:59 +02:00
Jeremy Kerr
db3f17e571 mctp: Allow local delivery to the null EID
[ Upstream commit 1f6c77ac9e ]

We may need to receive packets addressed to the null EID (==0), but
addressed to us at the physical layer.

This change adds a lookup for local routes when we see a packet
addressed to EID 0, and a local phys address.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 5093bbfc10 ("mctp: perform route lookups under a RCU read-side lock")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25 11:58:59 +02:00
Jeremy Kerr
c7caf669b8 net: mctp: purge receive queues on sk destruction
commit 60bd1d9008 upstream.

We may have pending skbs in the receive queue when the sk is being
destroyed; add a destructor to purge the queue.

MCTP doesn't use the error queue, so only the receive_queue is purged.

Fixes: 833ef3b91d ("mctp: Populate socket implementation")
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://lore.kernel.org/r/20230126064551.464468-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06 07:59:02 +01:00
Jeremy Kerr
e69c3a0d9d net: mctp: mark socks as dead on unhash, prevent re-add
[ Upstream commit b98e1a04e2 ]

Once a socket has been unhashed, we want to prevent it from being
re-used in a sk_key entry as part of a routing operation.

This change marks the sk as SOCK_DEAD on unhash, which prevents addition
into the net's key list.

We need to do this during the key add path, rather than key lookup, as
we release the net keys_lock between those operations.

Fixes: 4a992bbd36 ("mctp: Implement message fragmentation & reassembly")
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01 08:27:28 +01:00
Wei Yongjun
49d8a6e24a mctp: Fix an error handling path in mctp_init()
[ Upstream commit d4072058af ]

If mctp_neigh_init() return error, the routes resources should
be released in the error handling path. Otherwise some resources
leak.

Fixes: 4d8b931928 ("mctp: Add neighbour implementation")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Matt Johnston <matt@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20221108095517.620115-1-weiyongjun@huaweicloud.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:22 +01:00
Matt Johnston
71d28e5073 mctp: Fix check for dev_hard_header() result
[ Upstream commit 60be976ac4 ]

dev_hard_header() returns the length of the header, so
we need to test for negative errors rather than non-zero.

Fixes: 889b7da23a ("mctp: Add initial routing framework")
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 20:59:16 +02:00
Matt Johnston
812ed9b712 mctp: Don't let RTM_DELROUTE delete local routes
[ Upstream commit 76d001603c ]

We need to test against the existing route type, not
the rtm_type in the netlink request.

Fixes: 83f0a0b728 ("mctp: Specify route types, require rtm_type in RTM_*ROUTE messages")
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-08 09:04:53 +01:00
Eugene Syromiatnikov
aaf0562f71 mctp: handle the struct sockaddr_mctp padding fields
commit 1e4b50f06d upstream.

In order to have the padding fields actually usable in the future,
there have to be checks that user space doesn't supply non-zero garbage
there.  It is also worth setting these padding fields to zero, unless
it is known that they have been already zeroed.

Cc: stable@vger.kernel.org # v5.15
Fixes: 5a20dd46b8 ("mctp: Be explicit about struct sockaddr_mctp padding")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Acked-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-18 19:16:02 +01:00
Jeremy Kerr
581edcd0c8 mctp: perform route destruction under RCU read lock
The kernel test robot reports:

  [  843.509974][  T345] =============================
  [  843.524220][  T345] WARNING: suspicious RCU usage
  [  843.538791][  T345] 5.14.0-rc2-00606-g889b7da23abf #1 Not tainted
  [  843.553617][  T345] -----------------------------
  [  843.567412][  T345] net/mctp/route.c:310 RCU-list traversed in non-reader section!!

- we're missing the rcu read lock acquire around the destruction path.

This change adds the acquire/release - the path is already atomic, and
we're using the _rcu list iterators.

Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-08 11:29:16 +01:00
Jeremy Kerr
83f0a0b728 mctp: Specify route types, require rtm_type in RTM_*ROUTE messages
This change adds a 'type' attribute to routes, which can be parsed from
a RTM_NEWROUTE message. This will help to distinguish local vs. peer
routes in a future change.

This means userspace will need to set a correct rtm_type in RTM_NEWROUTE
and RTM_DELROUTE messages; we currently only accept RTN_UNICAST.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20210810023834.2231088-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-11 16:01:17 -07:00
Colin Ian King
df7ba0eb25 mctp: remove duplicated assignment of pointer hdr
The pointer hdr is being initialized and also re-assigned with the
same value from the call to function mctp_hdr. Static analysis reports
that the initializated value is unused. The second assignment is
duplicated and can be removed.

Addresses-Coverity: ("Unused value").
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05 10:56:01 +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
26ab3fcaf2 mctp: Add dest neighbour lladdr to route output
Now that we have a neighbour implementation, hook it up to the output
path to set the dest hardware address for outgoing packets.

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
4a992bbd36 mctp: Implement message fragmentation & reassembly
This change implements MCTP fragmentation (based on route & device MTU),
and corresponding reassembly.

The MCTP specification only allows for fragmentation on the originating
message endpoint, and reassembly on the destination endpoint -
intermediate nodes do not need to reassemble/refragment.  Consequently,
we only fragment in the local transmit path, and reassemble
locally-bound packets. Messages are required to be in-order, so we
simply cancel reassembly on out-of-order or missing packets.

In the fragmentation path, we just break up the message into MTU-sized
fragments; the skb structure is a simple copy for now, which we can later
improve with a shared data implementation.

For reassembly, we keep track of incoming message fragments using the
existing tag infrastructure, allocating a key on the (src,dest,tag)
tuple, and reassembles matching fragments into a skb->frag_list.

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
833ef3b91d mctp: Populate socket implementation
Start filling-out the socket syscalls: bind, sendmsg & recvmsg.

This requires an input route implementation, so we add to
mctp_route_input, allowing lookups on binds & message tags. This just
handles single-packet messages at present, we will add fragmentation in
a future change.

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
Matt Johnston
831119f887 mctp: Add neighbour netlink interface
This change adds the netlink interfaces for manipulating the MCTP
neighbour table.

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
Matt Johnston
06d2f4c583 mctp: Add netlink route management
This change adds RTM_GETROUTE, RTM_NEWROUTE & RTM_DELROUTE handlers,
allowing management of the MCTP route table.

Includes changes from Jeremy Kerr <jk@codeconstruct.com.au>.

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
Jeremy Kerr
8f601a1e4f mctp: Add base socket/protocol definitions
Add an empty socket implementation, plus initialisation/destruction
handlers.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:49 +01:00
Jeremy Kerr
bc49d8169a mctp: Add MCTP base
Add basic Kconfig, an initial (empty) af_mctp source object, and
{AF,PF}_MCTP definitions, and the required definitions for a new
protocol type.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:49 +01:00