linux.git/net/mctp, branch v6.6

mctp: perform route lookups under a RCU read-side lock

2023-10-11T02:43:22+00:00

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 , where
introducing a delay in the route lookup could cause a UAF on
simultaneous sendmsg() and route deletion.

Reported-by: Sili Luo 
Fixes: 889b7da23abf ("mctp: Add initial routing framework")
Cc: stable@vger.kernel.org
Signed-off-by: Jeremy Kerr 
Reviewed-by: Eric Dumazet 
Link: https://lore.kernel.org/r/29c4b0e67dc1bf3571df3982de87df90cae9b631.1696837310.git.jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski

sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)

2023-06-24T22:50:13+00:00

Remove ->sendpage() and ->sendpage_locked().  sendmsg() with
MSG_SPLICE_PAGES should be used instead.  This allows multiple pages and
multipage folios to be passed through.

Signed-off-by: David Howells 
Acked-by: Marc Kleine-Budde  # for net/can
cc: Jens Axboe 
cc: Matthew Wilcox 
cc: linux-afs@lists.infradead.org
cc: mptcp@lists.linux.dev
cc: rds-devel@oss.oracle.com
cc: tipc-discussion@lists.sourceforge.net
cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski

net: mctp: remove redundant RTN_UNICAST check

2023-06-17T07:25:24+00:00

Current mctp_newroute() contains two exactly same check against
rtm->rtm_type

static int mctp_newroute(...)
{
...
    if (rtm->rtm_type != RTN_UNICAST) { // (1)
        NL_SET_ERR_MSG(extack, "rtm_type must be RTN_UNICAST");
        return -EINVAL;
    }
...
    if (rtm->rtm_type != RTN_UNICAST) // (2)
        return -EINVAL;
...
}

This commits removes the (2) check as it is redundant.

Signed-off-by: Lin Ma 
Reviewed-by: Pavan Chebbi 
Acked-by: Jeremy Kerr 
Link: https://lore.kernel.org/r/20230615152240.1749428-1-linma@zju.edu.cn
Signed-off-by: Jakub Kicinski

mctp: remove MODULE_LICENSE in non-modules

2023-03-10T07:06:21+00:00

Since commit 8b41fc4454e ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.

So remove it in the files in this commit, none of which can be built as
modules.

Signed-off-by: Nick Alcock 
Suggested-by: Luis Chamberlain 
Cc: Hitomi Hasegawa 
Cc: Jeremy Kerr 
Cc: Matt Johnston 
Link: https://lore.kernel.org/r/20230308121230.5354-2-nick.alcock@oracle.com
Signed-off-by: Jakub Kicinski

net: mctp: purge receive queues on sk destruction

2023-01-28T08:26:09+00:00

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: 833ef3b91de6 ("mctp: Populate socket implementation")
Signed-off-by: Jeremy Kerr 
Reviewed-by: Pavan Chebbi 
Link: https://lore.kernel.org/r/20230126064551.464468-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski

net: mctp: mark socks as dead on unhash, prevent re-add

2023-01-25T13:07:37+00:00

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: 4a992bbd3650 ("mctp: Implement message fragmentation & reassembly")
Signed-off-by: Jeremy Kerr 
Signed-off-by: David S. Miller

net: mctp: hold key reference when looking up a general key

2023-01-25T13:07:37+00:00

Currently, we have a race where we look up a sock through a "general"
(ie, not directly associated with the (src,dest,tag) tuple) key, then
drop the key reference while still holding the key's sock.

This change expands the key reference until we've finished using the
sock, and hence the sock reference too.

Commit message changes from Jeremy Kerr .

Reported-by: Noam Rathaus 
Fixes: 73c618456dc5 ("mctp: locking, lifetime and validity changes for sk_keys")
Signed-off-by: Paolo Abeni 
Signed-off-by: Jeremy Kerr 
Signed-off-by: David S. Miller

net: mctp: move expiry timer delete to unhash

2023-01-25T13:07:37+00:00

Currently, we delete the key expiry timer (in sk->close) before
unhashing the sk. This means that another thread may find the sk through
its presence on the key list, and re-queue the timer.

This change moves the timer deletion to the unhash, after we have made
the key no longer observable, so the timer cannot be re-queued.

Fixes: 7b14e15ae6f4 ("mctp: Implement a timeout for tags")
Signed-off-by: Jeremy Kerr 
Signed-off-by: David S. Miller

net: mctp: add an explicit reference from a mctp_sk_key to sock

2023-01-25T13:07:37+00:00

Currently, we correlate the mctp_sk_key lifetime to the sock lifetime
through the sock hash/unhash operations, but this is pretty tenuous, and
there are cases where we may have a temporary reference to an unhashed
sk.

This change makes the reference more explicit, by adding a hold on the
sock when it's associated with a mctp_sk_key, released on final key
unref.

Fixes: 73c618456dc5 ("mctp: locking, lifetime and validity changes for sk_keys")
Signed-off-by: Jeremy Kerr 
Signed-off-by: David S. Miller

mctp: Remove device type check at unregister

2022-12-20T01:20:22+00:00

The unregister check could be incorrectly triggered if a netdev
changes its type after register. That is possible for a tun device
using TUNSETLINK ioctl, resulting in mctp unregister failing
and the netdev unregister waiting forever.

This was encountered by https://github.com/openthread/openthread/issues/8523

Neither check at register or unregister is required. They were added in
an attempt to track down mctp_ptr being set unexpectedly, which should
not happen in normal operation.

Fixes: 7b1871af75f3 ("mctp: Warn if pointer is set for a wrong dev type")
Signed-off-by: Matt Johnston 
Link: https://lore.kernel.org/r/20221215054933.2403401-1-matt@codeconstruct.com.au
Signed-off-by: Jakub Kicinski