Commit Graph

8 Commits

Author SHA1 Message Date
Florian Westphal 36704413db mptcp: setsockopt: add SO_MARK support
Value is synced to all subflows.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:10 -07:00
Florian Westphal 268b123874 mptcp: setsockopt: support SO_LINGER
Similar to PRIORITY/KEEPALIVE: needs to be mirrored to all subflows.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:10 -07:00
Florian Westphal 5d0a6bc82d mptcp: setsockopt: handle receive/send buffer and device bind
Similar to previous patch: needs to be mirrored to all subflows.

Device bind is simpler: it is only done on the initial (listener) sk.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:10 -07:00
Florian Westphal 1b3e7ede13 mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY
start with something simple: both take an integer value, both
need to be mirrored to all subflows.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:10 -07:00
Florian Westphal df00b087da mptcp: tag sequence_seq with socket state
Paolo Abeni suggested to avoid re-syncing new subflows because
they inherit options from listener. In case options were set on
listener but are not set on mptcp-socket there is no need to
do any synchronisation for new subflows.

This change sets sockopt_seq of new mptcp sockets to the seq of
the mptcp listener sock.

Subflow sequence is set to the embedded tcp listener sk.
Add a comment explaing why sk_state is involved in sockopt_seq
generation.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:10 -07:00
Florian Westphal 7896248983 mptcp: add skeleton to sync msk socket options to subflows
Handle following cases:
1. setsockopt is called with multiple subflows.
   Change might have to be mirrored to all of them.
   This is done directly in process context/setsockopt call.
2. Outgoing subflow is created after one or several setsockopt()
   calls have been made.  Old setsockopt changes should be
   synced to the new socket.
3. Incoming subflow, after setsockopt call(s).

Cases 2 and 3 are handled right after the join list is spliced to the conn
list.

Not all sockopt values can be just be copied by value, some require
helper calls.  Those can acquire socket lock (which can sleep).

If the join->conn list splicing is done from preemptible context,
synchronization can be done right away, otherwise its deferred to work
queue.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:10 -07:00
Paolo Abeni d9e4c12918 mptcp: only admit explicitly supported sockopt
Unrolling mcast state at msk dismantel time is bug prone, as
syzkaller reported:

======================================================
WARNING: possible circular locking dependency detected
5.11.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor905/8822 is trying to acquire lock:
ffffffff8d678fe8 (rtnl_mutex){+.+.}-{3:3}, at: ipv6_sock_mc_close+0xd7/0x110 net/ipv6/mcast.c:323

but task is already holding lock:
ffff888024390120 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1600 [inline]
ffff888024390120 (sk_lock-AF_INET6){+.+.}-{0:0}, at: mptcp6_release+0x57/0x130 net/mptcp/protocol.c:3507

which lock already depends on the new lock.

Instead we can simply forbid any mcast-related setsockopt.
Let's do the same with all other non supported sockopts.

Fixes: 717e79c867 ("mptcp: Add setsockopt()/getsockopt() socket operations")
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:09 -07:00
Paolo Abeni 0abdde82b1 mptcp: move sockopt function into a new file
The MPTCP sockopt implementation is going to be much
more big and complex soon. Let's move it to a different
source file.

No functional change intended.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16 15:23:09 -07:00