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commit bd11dc4fb969ec148e50cd87f88a78246dbc4d0b upstream.
SO_KEEPALIVE support has been added a while ago, as part of a series
"adding SOL_SOCKET" support. To have a full control of this keep-alive
feature, it is important to also support TCP_KEEP* socket options at the
SOL_TCP level.
Supporting them on the setsockopt() part is easy, it is just a matter of
remembering each value in the MPTCP sock structure, and calling
tcp_sock_set_keep*() helpers on each subflow. If the value is not
modified (0), calling these helpers will not do anything. For the
getsockopt() part, the corresponding value from the MPTCP sock structure
or the default one is simply returned. All of this is very similar to
other TCP_* socket options supported by MPTCP.
It looks important for kernels supporting SO_KEEPALIVE, to also support
TCP_KEEP* options as well: some apps seem to (wrongly) consider that if
the former is supported, the latter ones will be supported as well. But
also, not having this simple and isolated change is preventing MPTCP
support in some apps, and libraries like GoLang [1]. This is why this
patch is seen as a fix.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/383
Fixes: 1b3e7ede1365 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY")
Link: https://github.com/golang/go/issues/56539 [1]
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20240514011335.176158-3-martineau@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ conflicts in the same context, because commit 29b5e5ef8739 ("mptcp:
implement TCP_NOTSENT_LOWAT support") is not in this version ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b111d8fbd2cbc63e05f3adfbbe0d4df655dfcc5b upstream.
After the blamed commit below, the send buffer auto-tuning can
happen after that the mptcp_propagate_sndbuf() completes - via
the delegated action infrastructure.
We must check for write space even after such change or we risk
missing the wake-up event.
Fixes: 8005184fd1ca ("mptcp: refactor sndbuf auto-tuning")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-6-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a7cfe776637004a4c938fde78be4bd608c32c3ef upstream.
The local address id is accessed lockless by the NL PM, add
all the required ONCE annotation. There is a caveat: the local
id can be initialized late in the subflow life-cycle, and its
validity is controlled by the local_id_valid flag.
Remove such flag and encode the validity in the local_id field
itself with negative value before initialization. That allows
accessing the field consistently with a single read operation.
Fixes: 0ee4261a3681 ("mptcp: implement mptcp_pm_remove_subflow")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e4a0fa47e816e186f6b4c0055d07eeec42d11871 ]
Most MPTCP-level related fields are under the mptcp data lock
protection, but are written one-off without such lock at MPC
complete time, both for the client and the server
Leverage the mptcp_propagate_state() infrastructure to move such
initialization under the proper lock client-wise.
The server side critical init steps are done by
mptcp_subflow_fully_established(): ensure the caller properly held the
relevant lock, and avoid acquiring the same lock in the nested scopes.
There are no real potential races, as write access to such fields
is implicitly serialized by the MPTCP state machine; the primary
goal is consistency.
Fixes: d22f4988ffec ("mptcp: process MP_CAPABLE data option")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d9cd27b8cd191133e287e5de107f971136abe8a2 ]
Add a new MIB counter named MPTCP_MIB_CURRESTAB to count current
established MPTCP connections, similar to TCP_MIB_CURRESTAB. This is
useful to quickly list the number of MPTCP connections without having to
iterate over all of them.
This patch adds a new helper function mptcp_set_state(): if the state
switches from or to ESTABLISHED state, this newly added counter is
incremented. This helper is going to be used in the following patch.
Similar to MPTCP_INC_STATS(), a new helper called MPTCP_DEC_STATS() is
also needed to decrement a MIB counter.
Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e4a0fa47e816 ("mptcp: corner case locking for rx path fields initialization")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 337cebbd850f94147cee05252778f8f78b8c337f upstream.
Fastopen and PM-trigger subflow shutdown can race, as reported by
syzkaller.
In my first attempt to close such race, I missed the fact that
the subflow status can change again before the subflow_state_change
callback is invoked.
Address the issue additionally copying with all the states directly
reachable from TCP_FIN_WAIT1.
Fixes: 1e777f39b4d7 ("mptcp: add MSG_FASTOPEN sendmsg flag support")
Fixes: 4fd19a307016 ("mptcp: fix inconsistent state on fastopen race")
Cc: stable@vger.kernel.org
Reported-by: syzbot+c53d4d3ddb327e80bc51@syzkaller.appspotmail.com
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/458
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 013e3179dbd2bc756ce1dd90354abac62f65b739 upstream.
mptcp_rcv_space_init() is supposed to happen under the msk socket
lock, but active msk socket does that without such protection.
Leverage the existing mptcp_propagate_state() helper to that extent.
We need to ensure mptcp_rcv_space_init will happen before
mptcp_rcv_space_adjust(), and the release_cb does not assure that:
explicitly check for such condition.
While at it, move the wnd_end initialization out of mptcp_rcv_space_init(),
it never belonged there.
Note that the race does not produce ill effect in practice, but
change allows cleaning-up and defying better the locking model.
Fixes: a6b118febbab ("mptcp: add receive buffer auto-tuning")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bdd70eb68913c960acb895b00a8c62eb64715b1f upstream.
Such field is there to avoid acquiring the data lock in a few spots,
but it adds complexity to the already non trivial locking schema.
All the relevant call sites (mptcp-level re-injection, set socket
options), are slow-path, drop such field in favor of 'cb_flags', adding
the relevant locking.
This patch could be seen as an improvement, instead of a fix. But it
simplifies the next patch. The 'Fixes' tag has been added to help having
this series backported to stable.
Fixes: e9d09baca676 ("mptcp: avoid atomic bit manipulation when possible")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4fd19a30701659af5839b7bd19d1f05f05933ebe ]
The netlink PM can race with fastopen self-connect attempts, shutting
down the first subflow via:
MPTCP_PM_CMD_DEL_ADDR -> mptcp_nl_remove_id_zero_address ->
mptcp_pm_nl_rm_subflow_received -> mptcp_close_ssk
and transitioning such subflow to FIN_WAIT1 status before the syn-ack
packet is processed. The MPTCP code does not react to such state change,
leaving the connection in not-fallback status and the subflow handshake
uncompleted, triggering the following splat:
WARNING: CPU: 0 PID: 10630 at net/mptcp/subflow.c:1405 subflow_data_ready+0x39f/0x690 net/mptcp/subflow.c:1405
Modules linked in:
CPU: 0 PID: 10630 Comm: kworker/u4:11 Not tainted 6.6.0-syzkaller-14500-g1c41041124bd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Workqueue: bat_events batadv_nc_worker
RIP: 0010:subflow_data_ready+0x39f/0x690 net/mptcp/subflow.c:1405
Code: 18 89 ee e8 e3 d2 21 f7 40 84 ed 75 1f e8 a9 d7 21 f7 44 89 fe bf 07 00 00 00 e8 0c d3 21 f7 41 83 ff 07 74 07 e8 91 d7 21 f7 <0f> 0b e8 8a d7 21 f7 48 89 df e8 d2 b2 ff ff 31 ff 89 c5 89 c6 e8
RSP: 0018:ffffc90000007448 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888031efc700 RCX: ffffffff8a65baf4
RDX: ffff888043222140 RSI: ffffffff8a65baff RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000007
R10: 000000000000000b R11: 0000000000000000 R12: 1ffff92000000e89
R13: ffff88807a534d80 R14: ffff888021c11a00 R15: 000000000000000b
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa19a0ffc81 CR3: 000000007a2db000 CR4: 00000000003506f0
DR0: 000000000000d8dd DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
tcp_data_ready+0x14c/0x5b0 net/ipv4/tcp_input.c:5128
tcp_data_queue+0x19c3/0x5190 net/ipv4/tcp_input.c:5208
tcp_rcv_state_process+0x11ef/0x4e10 net/ipv4/tcp_input.c:6844
tcp_v4_do_rcv+0x369/0xa10 net/ipv4/tcp_ipv4.c:1929
tcp_v4_rcv+0x3888/0x3b30 net/ipv4/tcp_ipv4.c:2329
ip_protocol_deliver_rcu+0x9f/0x480 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x2e4/0x510 net/ipv4/ip_input.c:233
NF_HOOK include/linux/netfilter.h:314 [inline]
NF_HOOK include/linux/netfilter.h:308 [inline]
ip_local_deliver+0x1b6/0x550 net/ipv4/ip_input.c:254
dst_input include/net/dst.h:461 [inline]
ip_rcv_finish+0x1c4/0x2e0 net/ipv4/ip_input.c:449
NF_HOOK include/linux/netfilter.h:314 [inline]
NF_HOOK include/linux/netfilter.h:308 [inline]
ip_rcv+0xce/0x440 net/ipv4/ip_input.c:569
__netif_receive_skb_one_core+0x115/0x180 net/core/dev.c:5527
__netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5641
process_backlog+0x101/0x6b0 net/core/dev.c:5969
__napi_poll.constprop.0+0xb4/0x540 net/core/dev.c:6531
napi_poll net/core/dev.c:6600 [inline]
net_rx_action+0x956/0xe90 net/core/dev.c:6733
__do_softirq+0x21a/0x968 kernel/softirq.c:553
do_softirq kernel/softirq.c:454 [inline]
do_softirq+0xaa/0xe0 kernel/softirq.c:441
</IRQ>
<TASK>
__local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:381
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_nc_purge_paths+0x1ce/0x3c0 net/batman-adv/network-coding.c:471
batadv_nc_worker+0x9b1/0x10e0 net/batman-adv/network-coding.c:722
process_one_work+0x884/0x15c0 kernel/workqueue.c:2630
process_scheduled_works kernel/workqueue.c:2703 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
kthread+0x33c/0x440 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
</TASK>
To address the issue, catch the racing subflow state change and
use it to cause the MPTCP fallback. Such fallback is also used to
cause the first subflow state propagation to the msk socket via
mptcp_set_connected(). After this change, the first subflow can
additionally propagate the TCP_FIN_WAIT1 state, so rename the
helper accordingly.
Finally, if the state propagation is delayed to the msk release
callback, the first subflow can change to a different state in between.
Cache the relevant target state in a new msk-level field and use
such value to update the msk state at release time.
Fixes: 1e777f39b4d7 ("mptcp: add MSG_FASTOPEN sendmsg flag support")
Cc: stable@vger.kernel.org
Reported-by: <syzbot+c53d4d3ddb327e80bc51@syzkaller.appspotmail.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/458
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8005184fd1ca6aeb3fea36f4eb9463fc1b90c114 ]
The MPTCP protocol account for the data enqueued on all the subflows
to the main socket send buffer, while the send buffer auto-tuning
algorithm set the main socket send buffer size as the max size among
the subflows.
That causes bad performances when at least one subflow is sndbuf
limited, e.g. due to very high latency, as the MPTCP scheduler can't
even fill such buffer.
Change the send-buffer auto-tuning algorithm to compute the main socket
send buffer size as the sum of all the subflows buffer size.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-2-v1-9-9dc60939d371@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 4fd19a307016 ("mptcp: fix inconsistent state on fastopen race")
Signed-off-by: Sasha Levin <sashal@kernel.org>
The delegated action infrastructure is prone to the following
race: different CPUs can try to schedule different delegated
actions on the same subflow at the same time.
Each of them will check different bits via mptcp_subflow_delegate(),
and will try to schedule the action on the related per-cpu napi
instance.
Depending on the timing, both can observe an empty delegated list
node, causing the same entry to be added simultaneously on two different
lists.
The root cause is that the delegated actions infra does not provide
a single synchronization point. Address the issue reserving an additional
bit to mark the subflow as scheduled for delegation. Acquiring such bit
guarantee the caller to own the delegated list node, and being able to
safely schedule the subflow.
Clear such bit only when the subflow scheduling is completed, ensuring
proper barrier in place.
Additionally swap the meaning of the delegated_action bitmask, to allow
the usage of the existing helper to set multiple bit at once.
Fixes: bcd97734318d ("mptcp: use delegate action to schedule 3rd ack retrans")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231004-send-net-20231004-v1-1-28de4ac663ae@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
According to RFC 8684 section 3.3:
A connection is not closed unless [...] or an implementation-specific
connection-level send timeout.
Currently the MPTCP protocol does not implement such timeout, and
connection timing-out at the TCP-level never move to close state.
Introduces a catch-up condition at subflow close time to move the
MPTCP socket to close, too.
That additionally allows removing similar existing inside the worker.
Finally, allow some additional timeout for plain ESTABLISHED mptcp
sockets, as the protocol allows creating new subflows even at that
point and making the connection functional again.
This issue is actually present since the beginning, but it is basically
impossible to solve without a long chain of functional pre-requisites
topped by commit bbd49d114d57 ("mptcp: consolidate transition to
TCP_CLOSE in mptcp_do_fastclose()"). When backporting this current
patch, please also backport this other commit as well.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/430
Fixes: e16163b6e2b7 ("mptcp: refactor shutdown and close")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The msk socket uses to different timeout to track close related
events and retransmissions. The existing helpers do not indicate
clearly which timer they actually touch, making the related code
quite confusing.
Change the existing helpers name to avoid such confusion. No
functional change intended.
This patch is linked to the next one ("mptcp: fix dangling connection
hang-up"). The two patches are supposed to be backported together.
Cc: stable@vger.kernel.org # v5.11+
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch defines the default packet scheduler mptcp_sched_default.
Register it in mptcp_sched_init(), which is invoked in mptcp_proto_init().
Skip deleting this default scheduler in mptcp_unregister_scheduler().
Set msk->sched to the default scheduler when the input parameter of
mptcp_init_sched() is NULL.
Invoke mptcp_sched_default_get_subflow in get_send() and get_retrans()
if the defaut scheduler is set or msk->sched is NULL.
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-10-0c860fb256a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch defines two packet scheduler wrappers mptcp_sched_get_send()
and mptcp_sched_get_retrans(), invoke get_subflow() of msk->sched in
them.
Set data->reinject to true in mptcp_sched_get_retrans(), set it false in
mptcp_sched_get_send().
If msk->sched is NULL, use default functions mptcp_subflow_get_send()
and mptcp_subflow_get_retrans() to send data.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-7-0c860fb256a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch adds a new member scheduled in struct mptcp_subflow_context,
which will be set in the MPTCP scheduler context when the scheduler
picks this subflow to send data.
Add a new helper mptcp_subflow_set_scheduled() to set this flag using
WRITE_ONCE().
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-6-0c860fb256a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch adds a new struct member sched in struct mptcp_sock.
And two helpers mptcp_init_sched() and mptcp_release_sched() to
init and release it.
Init it with the sysctl scheduler in mptcp_init_sock(), copy the
scheduler from the parent in mptcp_sk_clone(), and release it in
__mptcp_destroy_sock().
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-5-0c860fb256a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch adds a new sysctl, named scheduler, to support for selection
of different schedulers. Export mptcp_get_scheduler helper to get this
sysctl.
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-4-0c860fb256a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch defines struct mptcp_sched_ops, which has three struct members,
name, owner and list, and four function pointers: init(), release() and
get_subflow().
The scheduler function get_subflow() have a struct mptcp_sched_data
parameter, which contains a reinject flag for retrans or not, a subflows
number and a mptcp_subflow_context array.
Add the scheduler registering, unregistering and finding functions to add,
delete and find a packet scheduler on the global list mptcp_sched_list.
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-3-0c860fb256a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Since the burst check conditions have moved out of the function
mptcp_subflow_get_send(), it makes all msk->last_snd useless.
This patch drops them as well as the macro MPTCP_RESET_SCHEDULER.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-2-0c860fb256a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Such field is now unused just as a flag to control the first subflow
deletion at close() time. Introduce a new bit flag for that and finally
drop the mentioned field.
As an intended side effect, now the first subflow sock is not freed
before close() even for passive sockets. The msk has no open/active
subflows if the first one is closed and the subflow list is singular,
update accordingly the state check in mptcp_stream_accept().
Among other benefits, the subflow removal, reduces the amount of memory
used on the client side for each mptcp connection, allows passive sockets
to go through successful accept()/disconnect()/connect() and makes return
error code consistent for failing both passive and active sockets.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/290
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the previous patch the __mptcp_nmpc_socket helper is used
only to ensure that the MPTCP socket is a suitable status - that
is, the mptcp capable handshake is not started yet.
Change the return value to the relevant subflow sock, to finally
remove the last references to first subflow socket in the MPTCP stack.
As a bonus, we can get rid of a few local variables in different
functions.
No functional change intended.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Despite commit 0ad529d9fd2b ("mptcp: fix possible divide by zero in
recvmsg()"), the mptcp protocol is still prone to a race between
disconnect() (or shutdown) and accept.
The root cause is that the mentioned commit checks the msk-level
flag, but mptcp_stream_accept() does acquire the msk-level lock,
as it can rely directly on the first subflow lock.
As reported by Christoph than can lead to a race where an msk
socket is accepted after that mptcp_subflow_queue_clean() releases
the listener socket lock and just before it takes destructive
actions leading to the following splat:
BUG: kernel NULL pointer dereference, address: 0000000000000012
PGD 5a4ca067 P4D 5a4ca067 PUD 37d4c067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 2 PID: 10955 Comm: syz-executor.5 Not tainted 6.5.0-rc1-gdc7b257ee5dd #37
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
RIP: 0010:mptcp_stream_accept+0x1ee/0x2f0 include/net/inet_sock.h:330
Code: 0a 09 00 48 8b 1b 4c 39 e3 74 07 e8 bc 7c 7f fe eb a1 e8 b5 7c 7f fe 4c 8b 6c 24 08 eb 05 e8 a9 7c 7f fe 49 8b 85 d8 09 00 00 <0f> b6 40 12 88 44 24 07 0f b6 6c 24 07 bf 07 00 00 00 89 ee e8 89
RSP: 0018:ffffc90000d07dc0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888037e8d020 RCX: ffff88803b093300
RDX: 0000000000000000 RSI: ffffffff833822c5 RDI: ffffffff8333896a
RBP: 0000607f82031520 R08: ffff88803b093300 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000003e83 R12: ffff888037e8d020
R13: ffff888037e8c680 R14: ffff888009af7900 R15: ffff888009af6880
FS: 00007fc26d708640(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000012 CR3: 0000000066bc5001 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
do_accept+0x1ae/0x260 net/socket.c:1872
__sys_accept4+0x9b/0x110 net/socket.c:1913
__do_sys_accept4 net/socket.c:1954 [inline]
__se_sys_accept4 net/socket.c:1951 [inline]
__x64_sys_accept4+0x20/0x30 net/socket.c:1951
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x47/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Address the issue by temporary removing the pending request socket
from the accept queue, so that racing accept() can't touch them.
After depleting the msk - the ssk still exists, as plain TCP sockets,
re-insert them into the accept queue, so that later inet_csk_listen_stop()
will complete the tcp socket disposal.
Fixes: 2a6a870e44dd ("mptcp: stops worker on unaccepted sockets at listener close")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/423
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/20230803-upstream-net-20230803-misc-fixes-6-5-v1-4-6671b1ab11cc@tessares.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The MPTCP code uses the assumption that the tcp_win_from_space() helper
does not use any TCP-specific field, and thus works correctly operating
on an MPTCP socket.
The commit dfa2f0483360 ("tcp: get rid of sysctl_tcp_adv_win_scale")
broke such assumption, and as a consequence most MPTCP connections stall
on zero-window event due to auto-tuning changing the rcv buffer size
quite randomly.
Address the issue syncing again the MPTCP auto-tuning code with the TCP
one. To achieve that, factor out the windows size logic in socket
independent helpers, and reuse them in mptcp_rcv_space_adjust(). The
MPTCP level scaling_ratio is selected as the minimum one from the all
the subflows, as a worst-case estimate.
Fixes: dfa2f0483360 ("tcp: get rid of sysctl_tcp_adv_win_scale")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Link: https://lore.kernel.org/r/20230720-upstream-net-next-20230720-mptcp-fix-rcv-buffer-auto-tuning-v1-1-175ef12b8380@tessares.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pass addr parameter to mptcp_pm_alloc_anno_list() instead of entry. We
can reduce the scope, e.g. in mptcp_pm_alloc_anno_list(), we only access
"entry->addr", we can then restrict to the pointer to "addr" then.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The user-space need to properly account the data received/sent by
individual subflows. When additional subflows are created and/or
closed during the MPTCP socket lifetime, the information currently
exposed via MPTCP_TCPINFO are not enough: subflows are identified only
by the sequential position inside the info dumps, and that will change
with the above mentioned events.
To solve the above problem, this patch introduces a new subflow
identifier that is unique inside the given MPTCP socket scope.
The initial subflow get the id 1 and the other subflows get incremental
values at join time.
Link: https://github.com/multipath-tcp/mptcp_net-next/issues/388
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently there are no data transfer counters accounting for all
the subflows used by a given MPTCP socket. The user-space can compute
such figures aggregating the subflow info, but that is inaccurate
if any subflow is closed before the MPTCP socket itself.
Add the new counters in the MPTCP socket itself and expose them
via the existing diag and sockopt. While touching mptcp_diag_fill_info(),
acquire the relevant locks before fetching the msk data, to ensure
better data consistency
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/385
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Thanks to the previous patch -- "mptcp: consolidate fallback and non
fallback state machine" -- we can finally drop the "temporary hack"
used to detect rx eof.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch unifies the three PM set_flags() interfaces:
mptcp_pm_nl_set_flags() in mptcp/pm_netlink.c for the in-kernel PM and
mptcp_userspace_pm_set_flags() in mptcp/pm_userspace.c for the
userspace PM.
They'll be switched in the common PM infterface mptcp_pm_set_flags() in
mptcp/pm.c based on whether token is NULL or not.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch unifies the three PM get_flags_and_ifindex_by_id() interfaces:
mptcp_pm_nl_get_flags_and_ifindex_by_id() in mptcp/pm_netlink.c for the
in-kernel PM and mptcp_userspace_pm_get_flags_and_ifindex_by_id() in
mptcp/pm_userspace.c for the userspace PM.
They'll be switched in the common PM infterface
mptcp_pm_get_flags_and_ifindex_by_id() in mptcp/pm.c based on whether
mptcp_pm_is_userspace() or not.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch unifies the three PM get_local_id() interfaces:
mptcp_pm_nl_get_local_id() in mptcp/pm_netlink.c for the in-kernel PM and
mptcp_userspace_pm_get_local_id() in mptcp/pm_userspace.c for the
userspace PM.
They'll be switched in the common PM infterface mptcp_pm_get_local_id()
in mptcp/pm.c based on whether mptcp_pm_is_userspace() or not.
Also put together the declarations of these three functions in protocol.h.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Rename local_address() with "mptcp_" prefix and export it in protocol.h.
This function will be re-used in the common PM code (pm.c) in the
following commit.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The specifications from [1] about the "REMOVE" command say:
Announce that an address has been lost to the peer
It was then only supposed to send a RM_ADDR and not trying to delete
associated subflows.
A new helper mptcp_pm_remove_addrs() is then introduced to do just
that, compared to mptcp_pm_remove_addrs_and_subflows() also removing
subflows.
To delete a subflow, the userspace daemon can use the "SUB_DESTROY"
command, see mptcp_nl_cmd_sf_destroy().
Fixes: d9a4594edabf ("mptcp: netlink: Add MPTCP_PM_CMD_REMOVE")
Link: https://github.com/multipath-tcp/mptcp/blob/mptcp_v0.96/include/uapi/linux/mptcp.h [1]
Cc: stable@vger.kernel.org
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the msk socket is cloned at MPC handshake time, a few
fields are initialized in a racy way outside mptcp_sk_clone()
and the msk socket lock.
The above is due historical reasons: before commit a88d0092b24b
("mptcp: simplify subflow_syn_recv_sock()") as the first subflow socket
carrying all the needed date was not available yet at msk creation
time
We can now refactor the code moving the missing initialization bit
under the socket lock, removing the init race and avoiding some
code duplication.
This will also simplify the next patch, as all msk->first write
access are now under the msk socket lock.
Fixes: 0397c6d85f9c ("mptcp: keep unaccepted MPC subflow into join list")
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The MPTCP can access the first subflow socket in a few spots
outside the socket lock scope. That is actually safe, as MPTCP
will delete the socket itself only after the msk sock close().
Still the such accesses causes a few KCSAN splats, as reported
by Christoph. Silence the harmless warning adding a few annotation
around the relevant accesses.
Fixes: 71ba088ce0aa ("mptcp: cleanup accept and poll")
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/402
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Ondrej reported a functional issue WRT timeout handling on connect
with a nice reproducer.
The problem is that the current mptcp connect waits for both the
MPTCP socket level timeout, and the first subflow socket timeout.
The latter is not influenced/touched by the exposed setsockopt().
Overall the above makes the SO_SNDTIMEO a no-op on connect.
Since mptcp_connect is invoked via inet_stream_connect and the
latter properly handle the MPTCP level timeout, we can address the
issue making the nested subflow level connect always unblocking.
This also allow simplifying a bit the code, dropping an ugly hack
to handle the fastopen and custom proto_ops connect.
The issues predates the blamed commit below, but the current resolution
requires the infrastructure introduced there.
Fixes: 54f1944ed6d2 ("mptcp: factor out mptcp_connect()")
Reported-by: Ondrej Mosnacek <omosnace@redhat.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/399
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mptcp_userspace_pm_append_new_local_addr() has always exclusively been
used in pm_userspace.c since its introduction in
commit 4638de5aefe5 ("mptcp: handle local addrs announced by userspace PMs").
So make it static.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the long run this will simplify the mptcp code and will
allow for more consistent behavior. Move the first subflow
allocation out of the sock->init ops into the __mptcp_nmpc_socket()
helper.
Since the first subflow creation can now happen after the first
setsockopt() we additionally need to invoke mptcp_sockopt_sync()
on it.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 3a236aef280e ("mptcp: refactor passive socket initialization"),
every mptcp_pm_fully_established() call is always invoked with a
GFP_ATOMIC argument. We can then drop it.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can change mptcp_sk() to propagate its argument const qualifier,
thanks to container_of_const().
We need to change few things to avoid build errors:
mptcp_set_datafin_timeout() and mptcp_rtx_head() have to accept
non-const sk pointers.
@msk local variable in mptcp_pending_tail() must be const.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Christoph after having refactored the passive
socket initialization, the mptcp listener shutdown path is prone
to an UaF issue.
BUG: KASAN: use-after-free in _raw_spin_lock_bh+0x73/0xe0
Write of size 4 at addr ffff88810cb23098 by task syz-executor731/1266
CPU: 1 PID: 1266 Comm: syz-executor731 Not tainted 6.2.0-rc59af4eaa31c1f6c00c8f1e448ed99a45c66340dd5 #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x6e/0x91
print_report+0x16a/0x46f
kasan_report+0xad/0x130
kasan_check_range+0x14a/0x1a0
_raw_spin_lock_bh+0x73/0xe0
subflow_error_report+0x6d/0x110
sk_error_report+0x3b/0x190
tcp_disconnect+0x138c/0x1aa0
inet_child_forget+0x6f/0x2e0
inet_csk_listen_stop+0x209/0x1060
__mptcp_close_ssk+0x52d/0x610
mptcp_destroy_common+0x165/0x640
mptcp_destroy+0x13/0x80
__mptcp_destroy_sock+0xe7/0x270
__mptcp_close+0x70e/0x9b0
mptcp_close+0x2b/0x150
inet_release+0xe9/0x1f0
__sock_release+0xd2/0x280
sock_close+0x15/0x20
__fput+0x252/0xa20
task_work_run+0x169/0x250
exit_to_user_mode_prepare+0x113/0x120
syscall_exit_to_user_mode+0x1d/0x40
do_syscall_64+0x48/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
The msk grace period can legitly expire in between the last
reference count dropped in mptcp_subflow_queue_clean() and
the later eventual access in inet_csk_listen_stop()
After the previous patch we don't need anymore special-casing
msk listener socket cleanup: the mptcp worker will process each
of the unaccepted msk sockets.
Just drop the now unnecessary code.
Please note this commit depends on the two parent ones:
mptcp: refactor passive socket initialization
mptcp: use the workqueue to destroy unaccepted sockets
Fixes: 6aeed9045071 ("mptcp: fix race on unaccepted mptcp sockets")
Cc: stable@vger.kernel.org
Reported-and-tested-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/346
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Christoph reported a UaF at token lookup time after having
refactored the passive socket initialization part:
BUG: KASAN: use-after-free in __token_bucket_busy+0x253/0x260
Read of size 4 at addr ffff88810698d5b0 by task syz-executor653/3198
CPU: 1 PID: 3198 Comm: syz-executor653 Not tainted 6.2.0-rc59af4eaa31c1f6c00c8f1e448ed99a45c66340dd5 #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x6e/0x91
print_report+0x16a/0x46f
kasan_report+0xad/0x130
__token_bucket_busy+0x253/0x260
mptcp_token_new_connect+0x13d/0x490
mptcp_connect+0x4ed/0x860
__inet_stream_connect+0x80e/0xd90
tcp_sendmsg_fastopen+0x3ce/0x710
mptcp_sendmsg+0xff1/0x1a20
inet_sendmsg+0x11d/0x140
__sys_sendto+0x405/0x490
__x64_sys_sendto+0xdc/0x1b0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
We need to properly clean-up all the paired MPTCP-level
resources and be sure to release the msk last, even when
the unaccepted subflow is destroyed by the TCP internals
via inet_child_forget().
We can re-use the existing MPTCP_WORK_CLOSE_SUBFLOW infra,
explicitly checking that for the critical scenario: the
closed subflow is the MPC one, the msk is not accepted and
eventually going through full cleanup.
With such change, __mptcp_destroy_sock() is always called
on msk sockets, even on accepted ones. We don't need anymore
to transiently drop one sk reference at msk clone time.
Please note this commit depends on the parent one:
mptcp: refactor passive socket initialization
Fixes: 58b09919626b ("mptcp: create msk early")
Cc: stable@vger.kernel.org
Reported-and-tested-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/347
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If an MPTCP socket has been created with AF_INET6 and the IPV6_V6ONLY
option has been set, the userspace PM would allow creating subflows
using IPv4 addresses, e.g. mapped in v6.
The kernel side of userspace PM will also accept creating subflows with
local and remote addresses having different families. Depending on the
subflow socket's family, different behaviours are expected:
- If AF_INET is forced with a v6 address, the kernel will take the last
byte of the IP and try to connect to that: a new subflow is created
but to a non expected address.
- If AF_INET6 is forced with a v4 address, the kernel will try to
connect to a v4 address (v4-mapped-v6). A -EBADF error from the
connect() part is then expected.
It is then required to check the given families can be accepted. This is
done by using a new helper for addresses family matching, taking care of
IPv4 vs IPv4-mapped-IPv6 addresses. This helper will be re-used later by
the in-kernel path-manager to use mixed IPv4 and IPv6 addresses.
While at it, a clear error message is now reported if there are some
conflicts with the families that have been passed by the userspace.
Fixes: 702c2f646d42 ("mptcp: netlink: allow userspace-driven subflow establishment")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Let the caller specify the to-be-created subflow family.
For a given MPTCP socket created with the AF_INET6 family, the current
userspace PM can already ask the kernel to create subflows in v4 and v6.
If "plain" IPv4 addresses are passed to the kernel, they are
automatically mapped in v6 addresses "by accident". This can be
problematic because the userspace will need to pass different addresses,
now the v4-mapped-v6 addresses to destroy this new subflow.
On the other hand, if the MPTCP socket has been created with the AF_INET
family, the command to create a subflow in v6 will be accepted but the
result will not be the one as expected as new subflow will be created in
IPv4 using part of the v6 addresses passed to the kernel: not creating
the expected subflow then.
No functional change intended for the in-kernel PM where an explicit
enforcement is currently in place. This arbitrary enforcement will be
leveraged by other patches in a future version.
Fixes: 702c2f646d42 ("mptcp: netlink: allow userspace-driven subflow establishment")
Cc: stable@vger.kernel.org
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>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
