The retransmit head will be NULL in case there is no in-flight data
(meaning all data injected into network has been acked).
In that case the retransmit timer is stopped.
This is only correct if there is no more pending, not-yet-sent data.
If there is, the retransmit timer needs to set the PENDING bit again so
that mptcp tries to send the remaining (new) data once a subflow can accept
more data.
Also, mptcp_subflow_get_retrans() has to be called unconditionally.
This function checks for subflows that have become unresponsive and marks
them as stale, so in the case where the rtx queue is empty, subflows
will never be marked stale which prevents available backup subflows from
becoming eligible for transmit.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/226
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>
The update on recovery is not correct.
msk->tx_pending_data += msk->snd_nxt - rtx_head->data_seq;
will update tx_pending_data multiple times when a subflow is declared
stale while earlier recovery is still in progress.
This means that tx_pending_data will still be positive even after
all data as has been transmitted.
Rather than fix it, remove this field: there are no consumers.
The outstanding data byte count can be computed either via
"msk->write_seq - rtx_head->data_seq" or
"msk->write_seq - msk->snd_una".
The latter is more recent/accurate estimate as rtx_head adjustment
is deferred until mptcp lock can be acquired.
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>
We have a few more places where the mptcp code duplicates
lockdep_assert_held_once(). Let's use the existing macro and
avoid a bunch of compiler's conditional.
Reviewed-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>
When recovering after a link failure, snd_nxt should not be set to a
lower value. Else, update of snd_nxt is broken because:
msk->snd_nxt += ret; (where ret is number of bytes sent)
assumes that snd_nxt always moves forward.
After reduction, its possible that snd_nxt update gets out of sync:
dfrag we just sent might have had a data sequence number even past
recovery_snd_nxt.
This change factors the common msk state update to a helper
and updates snd_nxt based on the current dfrag data sequence number.
The conditional is required for the recovery phase where we may
re-transmit old dfrags that are before current snd_nxt.
After this change, snd_nxt only moves forward and covers all in-sequence
data that was transmitted.
recovery_snd_nxt is retained to detect when recovery has completed.
Fixes: 1e1d9d6f11 ("mptcp: handle pending data on closed subflow")
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>
We want to revert the skb TX cache, but MPTCP is currently
using it unconditionally.
Rework the MPTCP tx code, so that tcp_tx_skb_cache is not
needed anymore: do the whole coalescing check, skb allocation
skb initialization/update inside mptcp_sendmsg_frag(), quite
alike the current TCP code.
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian noted that if mptcp_alloc_tx_skb() allocation fails
in __mptcp_push_pending(), we can end-up invoking
mptcp_push_release()/tcp_push() with a zero mss, causing
a divide by 0 error.
This change addresses the issue refactoring the skb allocation
code checking if skb collapsing will happen for sure and doing
the skb allocation only after such check. Skb allocation will
now happen only after the call to tcp_send_mss() which
correctly initializes mss_now.
As side bonuses we now fill the skb tx cache only when needed,
and this also clean-up a bit the output path.
v1 -> v2:
- use lockdep_assert_held_once() - Jakub
- fix indentation - Jakub
Reported-by: Florian Westphal <fw@strlen.de>
Fixes: 724cfd2ee8 ("mptcp: allocate TX skbs in msk context")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Florian noted the locking schema used by __mptcp_push_pending()
is hard to follow, let's add some more descriptive comments
and drop an unneeded and confusing check.
Suggested-by: Florian Westphal <fw@strlen.de>
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>
This makes input options processing more consistent with
output ones and will simplify the next patch.
Also avoid clearing the suboption field after processing
it, since it's not needed.
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>
This allows monitoring exceptional events like
active backup scenarios.
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>
The msk can use backup subflows to transmit in-sequence data
only if there are no other active subflow. On active backup
scenario, the MPTCP connection can do forward progress only
due to MPTCP retransmissions - rtx can pick backup subflows.
This patch introduces a new flag flow MPTCP subflows: if the
underlying TCP connection made no progresses for long time,
and there are other less problematic subflows available, the
given subflow become stale.
Stale subflows are not considered active: if all non backup
subflows become stale, the MPTCP scheduler can pick backup
subflows for plain transmissions.
Stale subflows can return in active state, as soon as any reply
from the peer is observed.
Active backup scenarios can now leverage the available b/w
with no restrinction.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/207
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>
The PM can close active subflow, e.g. due to ingress RM_ADDR
option. Such subflow could carry data still unacked at the
MPTCP-level, both in the write and the rtx_queue, which has
never reached the other peer.
Currently the mptcp-level retransmission will deliver such data,
but at a very low rate (at most 1 DSM for each MPTCP rtx interval).
We can speed-up the recovery a lot, moving all the unacked in the
tcp write_queue, so that it will be pushed again via other
subflows, at the speed allowed by them.
Also make available the new helper for later patches.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/207
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>
The current mptcp re-inject strategy is very aggressive,
we have mptcp-level retransmissions even on single subflow
connection, if the link in-use is lossy.
Let's be a little more conservative: we do retransmit
only if at least a subflow has write and rtx queue empty.
Additionally use the backup subflows only if the active
subflows are stale - no progresses in at least an rtx period
and ignore stale subflows for rtx timeout update
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/207
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>
As reported by Maxim, we have a lot of MPTCP-level
retransmissions when multilple links with different latencies
are in use.
This patch refactor the mptcp-level timeout accounting so that
the maximum of all the active subflow timeout is used. To avoid
traversing the subflow list multiple times, the update is
performed inside the packet scheduler.
Additionally clean-up a bit timeout handling.
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>
After commit 879526030c ("mptcp: protect the rx path with
the msk socket spinlock") the rmem currently used by a given
msk is really sk_rmem_alloc - rmem_released.
The safety check in mptcp_data_ready() does not take the above
in due account, as a result legit incoming data is kept in
subflow receive queue with no reason, delaying or blocking
MPTCP-level ack generation.
This change addresses the issue introducing a new helper to fetch
the rmem memory and using it as needed. Additionally add a MIB
counter for the exceptional event described above - the peer is
misbehaving.
Finally, introduce the required annotation when rmem_released is
updated.
Fixes: 879526030c ("mptcp: protect the rx path with the msk socket spinlock")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/211
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>
Trivial conflict in net/netfilter/nf_tables_api.c.
Duplicate fix in tools/testing/selftests/net/devlink_port_split.py
- take the net-next version.
skmsg, and L4 bpf - keep the bpf code but remove the flags
and err params.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Dan Carpenter reported an issue introduced in
commit fde56eea01 ("mptcp: refine mptcp_cleanup_rbuf") where a new
boolean (ack_pending) is masked with 0x9.
This is not the intention to ignore values by using a boolean. This
variable should not have a 'bool' type: we should keep the 'u8' to allow
this comparison.
Fixes: fde56eea01 ("mptcp: refine mptcp_cleanup_rbuf")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current cleanup rbuf tries a bit too hard to avoid acquiring
the subflow socket lock. We may end-up delaying the needed ack,
or skip acking a blocked subflow.
Address the above extending the conditions used to trigger the cleanup
to reflect more closely what TCP does and invoking tcp_cleanup_rbuf()
on all the active subflows.
Note that we can't replicate the exact tests implemented in
tcp_cleanup_rbuf(), as MPTCP lacks some of the required info - e.g.
ping-pong mode.
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>
The msk socket state is currently updated in a few spots without
owning the msk socket lock itself.
Some of such operations are safe, as they happens before exposing
the msk socket to user-space and can't race with other changes.
A couple of them, at connect time, can actually race with close()
or shutdown(), leaving breaking the socket state machine.
This change addresses the issue moving such update under the msk
socket lock with the usual:
<acquire spinlock>
<check sk lock onwers>
<ev defer to release_cb>
scheme.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/56
Fixes: 8fd738049a ("mptcp: fallback in case of simultaneous connect")
Fixes: c3c123d16c ("net: mptcp: don't hang in mptcp_sendmsg() after TCP fallback")
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>
Currently we check the msk state to avoid enqueuing new
skbs at msk shutdown time.
Such test is racy - as we can't acquire the msk socket lock -
and useless, as the caller already checked the subflow
field 'disposable', covering the same scenario in a race
free manner - read and updated under the ssk socket lock.
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>
If we don't flush entirely the receive queue, we need set
again such bit later. We can simply avoid clearing it.
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>
There are a bunch of callsite where the ssk socket
lock is acquired using the full-blown version eligible for
the fast variant. Let's move to the latter.
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>
The mentioned cache was introduced to reduce the number of skb
allocation in atomic context, but the required complexity is
excessive.
This change remove the mentioned cache.
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>
Trivial conflicts in net/can/isotp.c and
tools/testing/selftests/net/mptcp/mptcp_connect.sh
scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c
to include/linux/ptp_clock_kernel.h in -next so re-apply
the fix there.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If the MPTCP-level checksum is enabled, on re-injections we
must spool a complete DSS, or the receive side will not be
able to compute the csum and process any data.
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>
This patch added a new flag csum_reqd in struct mptcp_options_received, if
the flag MPTCP_CAP_CHECKSUM_REQD is set in the receiving MP_CAPABLE
suboption, set this flag.
In mptcp_sk_clone and subflow_finish_connect, if the csum_reqd flag is set,
enable the msk->csum_enabled flag.
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch added a new member named csum in struct mptcp_ext, implemented
a new function named mptcp_generate_data_checksum().
Generate the data checksum in mptcp_sendmsg_frag, save it in mpext->csum.
Note that we must generate the csum for zero window probe, too.
Do the csum update incrementally, to avoid multiple csum computation
when the data is appended to existing skb.
Note that in a later patch we will skip unneeded csum related operation.
Changes not included here to keep the delta small.
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch added a new member named csum_enabled in struct mptcp_sock,
used a dummy mptcp_is_checksum_enabled() helper to initialize it.
Also added a new member named mptcpi_csum_enabled in struct mptcp_info
to expose the csum_enabled flag.
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we rely on the subflow->data_avail field, which is subject to
races:
ssk1
skb len = 500 DSS(seq=1, len=1000, off=0)
# data_avail == MPTCP_SUBFLOW_DATA_AVAIL
ssk2
skb len = 500 DSS(seq = 501, len=1000)
# data_avail == MPTCP_SUBFLOW_DATA_AVAIL
ssk1
skb len = 500 DSS(seq = 1, len=1000, off =500)
# still data_avail == MPTCP_SUBFLOW_DATA_AVAIL,
# as the skb is covered by a pre-existing map,
# which was in-sequence at reception time.
Instead we can explicitly check if some has been received in-sequence,
propagating the info from __mptcp_move_skbs_from_subflow().
Additionally add the 'ONCE' annotation to the 'data_avail' memory
access, as msk will read it outside the subflow socket lock.
Fixes: 648ef4b886 ("mptcp: Implement MPTCP receive path")
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>
If the host is under sever memory pressure, and RX forward
memory allocation for the msk fails, we try to borrow the
required memory from the ingress subflow.
The current attempt is a bit flaky: if skb->truesize is less
than SK_MEM_QUANTUM, the ssk will not release any memory, and
the next schedule will fail again.
Instead, directly move the required amount of pages from the
ssk to the msk, if available
Fixes: 9c3f94e168 ("mptcp: add missing memory scheduling in the rx path")
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>
This adds support for SO_TIMESTAMP(NS). Timestamps are passed to
userspace in the same way as for plain tcp sockets.
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>
MPTCP sk_forward_memory handling is a bit special, as such field
is protected by the msk socket spin_lock, instead of the plain
socket lock.
Currently we have a code path updating such field without handling
the relevant lock:
__mptcp_retrans() -> __mptcp_clean_una_wakeup()
Several helpers in __mptcp_clean_una_wakeup() will update
sk_forward_alloc, possibly causing such field corruption, as reported
by Matthieu.
Address the issue providing and using a new variant of blamed function
which explicitly acquires the msk spin lock.
Fixes: 64b9cea7a0 ("mptcp: fix spurious retransmissions")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/172
Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Tested-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: Jakub Kicinski <kuba@kernel.org>
We can't use tcp_set_congestion_control() on an mptcp socket, as
such function can end-up accessing a tcp-specific field -
prior_ssthresh - causing an OOB access.
To allow propagating the correct ca algo on subflow, cache the ca
name at initialization time.
Additionally avoid overriding the user-selected CA (if any) at
clone time.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/182
Fixes: aa1fbd94e5 ("mptcp: sockopt: add TCP_CONGESTION and TCP_INFO")
Acked-by: Florian Westphal <fw@strlen.de>
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>
Maxim reported several issues when forcing a TCP transparent proxy
to use the MPTCP protocol for the inbound connections. He also
provided a clean reproducer.
The problem boils down to 'mptcp_frag_can_collapse_to()' assuming
that only MPTCP will use the given page_frag.
If others - e.g. the plain TCP protocol - allocate page fragments,
we can end-up re-using already allocated memory for mptcp_data_frag.
Fix the issue ensuring that the to-be-expanded data fragment is
located at the current page frag end.
v1 -> v2:
- added missing fixes tag (Mat)
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/178
Reported-and-tested-by: Maxim Galaganov <max@internet.ru>
Fixes: 18b683bff8 ("mptcp: queue data for mptcp level retransmission")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for MSG_PEEK flag. Packets are not removed
from the receive_queue if MSG_PEEK set in recv() system call.
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently mptcp_sendmsg() fails with EOPNOTSUPP if the
user-space provides some unsupported flag. That is unexpected
and may foul existing applications migrated to MPTCP, which
expect a different behavior.
Change the mentioned function to silently ignore the unsupported
flags except MSG_FASTOPEN. This is the only flags currently not
supported by MPTCP with user-space visible side-effects.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/162
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>
The mentioned flag is currently silenlty ignored. This
change implements the TCP-like behaviour, dropping the
pending data up to the specified length.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Sigend-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mptcp_recvmsg() currently silently ignores MSG_ERRQUEUE, returning
input data instead of error cmsg.
This change provides a dummy implementation for MSG_ERRQUEUE - always
returns no data. That is consistent with the current lack of a suitable
IP_RECVERR setsockopt() support.
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>
With this change, the MPTCP-level retransmission timer is used to resend
DATA_FIN. The retranmit timer is not stopped while waiting for a
MPTCP-level ACK of DATA_FIN, and retransmitted DATA_FINs are sent on all
subflows. The retry interval starts at TCP_RTO_MIN and then doubles on
each attempt, up to TCP_RTO_MAX.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/146
Fixes: 43b54c6ee3 ("mptcp: Use full MPTCP-level disconnect state machine")
Acked-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>
This patch used the macro helper mptcp_for_each_subflow() instead of
list_for_each_entry() in mptcp_close.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch added a tracepoint in the packet scheduler function
mptcp_subflow_get_send().
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch moved the static function mptcp_subflow_active to protocol.h
as an inline one.
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some of the sequence numbers are printed as the negative ones in the debug
log:
[ 46.250932] MPTCP: DSS
[ 46.250940] MPTCP: data_fin=0 dsn64=0 use_map=0 ack64=1 use_ack=1
[ 46.250948] MPTCP: data_ack=2344892449471675613
[ 46.251012] MPTCP: msk=000000006e157e3f status=10
[ 46.251023] MPTCP: msk=000000006e157e3f snd_data_fin_enable=0 pending=0 snd_nxt=2344892449471700189 write_seq=2344892449471700189
[ 46.251343] MPTCP: msk=00000000ec44a129 ssk=00000000f7abd481 sending dfrag at seq=-1658937016627538668 len=100 already sent=0
[ 46.251360] MPTCP: data_seq=16787807057082012948 subflow_seq=1 data_len=100 dsn64=1
This patch used the format specifier %u instead of %d for the unsigned int
values to fix it.
Fixes: d9ca1de8c0 ("mptcp: move page frag allocation in mptcp_sendmsg()")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP_CONGESTION is set for all subflows.
The mptcp socket gains icsk_ca_ops too so it can be used to keep the
authoritative state that should be set on new/future subflows.
TCP_INFO will return first subflow only.
The out-of-tree kernel has a MPTCP_INFO getsockopt, this could be added
later on.
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>
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>
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>
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>
This change reverts commit 86581852d7 ("mptcp: forbit mcast-related sockopt on MPTCP sockets").
As announced in the cover letter of the mentioned patch above, the
following commits introduce a larger MPTCP sockopt implementation
refactor.
This time, we switch from a blocklist to an allowlist. This is safer for
the future where new sockoptions could be added while not being fully
supported with MPTCP sockets and thus causing unstabilities.
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
MAINTAINERS
- keep Chandrasekar
drivers/net/ethernet/mellanox/mlx5/core/en_main.c
- simple fix + trust the code re-added to param.c in -next is fine
include/linux/bpf.h
- trivial
include/linux/ethtool.h
- trivial, fix kdoc while at it
include/linux/skmsg.h
- move to relevant place in tcp.c, comment re-wrapped
net/core/skmsg.c
- add the sk = sk // sk = NULL around calls
net/tipc/crypto.c
- trivial
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The MPTCP reset option allows to carry a mptcp-specific error code that
provides more information on the nature of a connection reset.
Reset option data received gets stored in the subflow context so it can
be sent to userspace via the 'subflow closed' netlink event.
When a subflow is closed, the desired error code that should be sent to
the peer is also placed in the subflow context structure.
If a reset is sent before subflow establishment could complete, e.g. on
HMAC failure during an MP_JOIN operation, the mptcp skb extension is
used to store the reset information.
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>
Currently we explicitly check for the first subflow being
NULL in a couple of places, even if we don't need any
special actions in such scenario.
Just drop the unneeded checks, to avoid confusion.
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>
We are not currently tracking the active MPTCP connection
attempts. Let's add the related counters.
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>
If the MPTCP protocol is unable to create a new token,
the socket fallback to plain TCP, let's keep track
of such events via a specific MIB.
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>
This change reverts commit ad98dd3705 ("mptcp: provide subflow aware
release function"). The latter introduced a deadlock spotted by
syzkaller and is not needed anymore after the previous commit.
Fixes: ad98dd3705 ("mptcp: provide subflow aware release function")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 forbit any mcast-related setsockopt
Fixes: 717e79c867 ("mptcp: Add setsockopt()/getsockopt() socket operations")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the previous patch we can easily avoid invoking
the workqueue to perform the retransmission, if the
msk socket lock is held at rtx timer expiration.
This also simplifies the relevant code.
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>
The MPTCP_PUSH_PENDING define is 6 and these tests should be testing if
BIT(6) is set.
Fixes: c2e6048fa1 ("mptcp: fix race in release_cb")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
__mptcp_clean_una() can free write memory and should wake-up
user-space processes when needed.
When such function is invoked by the MPTCP receive path, the wakeup
is not needed, as the TCP stack will later trigger subflow_write_space
which will do the wakeup as needed.
Other __mptcp_clean_una() call sites need an additional wakeup check
Let's bundle the relevant code in a new helper and use it.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/165
Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
Fixes: 64b9cea7a0 ("mptcp: fix spurious retransmissions")
Tested-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>
If we receive a MPTCP_PUSH_PENDING even from a subflow when
mptcp_release_cb() is serving the previous one, the latter
will be delayed up to the next release_sock(msk).
Address the issue implementing a test/serve loop for such
event.
Additionally rename the push helper to __mptcp_push_pending()
to be more consistent with the existing code.
Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
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>
Will simplify the following patch, 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>
Just like with last_snd, we have to NULL 'first' on subflow close.
ack_hint isn't strictly required (its never dereferenced), but better to
clear this explicitly as well instead of making it an exception.
msk->first is dereferenced unconditionally at accept time, but
at that point the ssk is not on the conn_list yet -- this means
worker can't see it when iterating the conn_list.
Reported-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
Christoph Paasch reported following crash:
dst_release underflow
WARNING: CPU: 0 PID: 1319 at net/core/dst.c:175 dst_release+0xc1/0xd0 net/core/dst.c:175
CPU: 0 PID: 1319 Comm: syz-executor217 Not tainted 5.11.0-rc6af8e85128b4d0d24083c5cac646e891227052e0c #70
Call Trace:
rt_cache_route+0x12e/0x140 net/ipv4/route.c:1503
rt_set_nexthop.constprop.0+0x1fc/0x590 net/ipv4/route.c:1612
__mkroute_output net/ipv4/route.c:2484 [inline]
...
The worker leaves msk->subflow alone even when it
happened to close the subflow ssk associated with it.
Fixes: 866f26f2a9 ("mptcp: always graft subflow socket to parent")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/157
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
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>
Send logic caches last active subflow in the msk, so it needs to be
cleared when the cached subflow is closed.
Fixes: d5f49190de ("mptcp: allow picking different xmit subflows")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/155
Reported-by: Christoph Paasch <cpaasch@apple.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
mptcp re-used inet(6)_release, so the subflow sockets are ignored.
Need to invoke ip(v6)_mc_drop_socket function to ensure mcast join
resources get free'd.
Fixes: 717e79c867 ("mptcp: Add setsockopt()/getsockopt() socket operations")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/110
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently we move orphaned msk sockets directly from FIN_WAIT2
state to CLOSE, with the rationale that incoming additional
data could be just dropped by the TCP stack/TW sockets.
Anyhow we miss sending MPTCP-level ack on incoming DATA_FIN,
and that may hang the peers.
Fixes: e16163b6e2 ("mptcp: refactor shutdown and close")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Allow userspace (mptcpd) to subscribe to mptcp genl multicast events.
This implementation reuses the same event API as the mptcp kernel fork
to ease integration of existing tools, e.g. mptcpd.
Supported events include:
1. start and close of an mptcp connection
2. start and close of subflows (joins)
3. announce and withdrawals of addresses
4. subflow priority (backup/non-backup) change.
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
Once event support is added this may need to allocate memory while msk
lock is held with softirqs disabled.
Not using lock_fast also allows to do the allocation with GFP_KERNEL.
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>
Pass the first/initial subflow to the existing functions so they can
pass this on to the notification handler that is added later in the
series.
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>
In case mptcp socket is already dead the entire mptcp socket
will be freed. We can avoid the close check in this case.
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>
When remote side closes a subflow we should schedule the worker to
dispose of the subflow in a timely manner.
Otherwise, SF_CLOSED event won't be generated until the mptcp
socket itself is closing or local side is closing another subflow.
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>
Prepare for subflow close events:
When mptcp connection is torn down its enough to send the mptcp socket
close notification rather than a subflow close event for all of the
subflows followed by the mptcp close event.
This splits the helper: mptcp_close_ssk() will emit the close
notification, __mptcp_close_ssk will not.
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>
Allows to make some functions static and avoids acquire of the pm
spinlock in protocol.c.
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>
Currently we do not schedule the MPTCP retransmission
timer after pushing the data when such action happens
in the subflow context.
This may cause hang-up on active-backup scenarios, or
even when only single subflow msks are involved, if we lost
some peer's ack.
Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
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>
Move mptcp_cleanup_rbuf() related checks inside the mentioned
helper and extend them to mirror TCP checks more closely.
Additionally drop the 'rmem_pending' hack, since commit 879526030c
("mptcp: protect the rx path with the msk socket spinlock") we
can use instead 'rmem_released'.
Fixes: ea4ca586b1 ("mptcp: refine MPTCP-level ack scheduling")
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>
Syzkaller was able to trigger the following splat again:
WARNING: CPU: 1 PID: 12512 at net/mptcp/protocol.c:761 mptcp_reset_timer+0x12a/0x160 net/mptcp/protocol.c:761
Modules linked in:
CPU: 1 PID: 12512 Comm: kworker/1:6 Not tainted 5.10.0-rc6 #52
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: events mptcp_worker
RIP: 0010:mptcp_reset_timer+0x12a/0x160 net/mptcp/protocol.c:761
Code: e8 4b 0c ad ff e8 56 21 88 fe 48 b8 00 00 00 00 00 fc ff df 48 c7 04 03 00 00 00 00 48 83 c4 40 5b 5d 41 5c c3 e8 36 21 88 fe <0f> 0b 41 bc c8 00 00 00 eb 98 e8 e7 b1 af fe e9 30 ff ff ff 48 c7
RSP: 0018:ffffc900018c7c68 EFLAGS: 00010293
RAX: ffff888108cb1c80 RBX: 1ffff92000318f8d RCX: ffffffff82ad0307
RDX: 0000000000000000 RSI: ffffffff82ad036a RDI: 0000000000000007
RBP: ffff888113e2d000 R08: ffff888108cb1c80 R09: ffffed10227c5ab7
R10: ffff888113e2d5b7 R11: ffffed10227c5ab6 R12: 0000000000000000
R13: ffff88801f100000 R14: ffff888113e2d5b0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff88811b500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd76a874ef8 CR3: 000000001689c005 CR4: 0000000000170ee0
Call Trace:
mptcp_worker+0xaa4/0x1560 net/mptcp/protocol.c:2334
process_one_work+0x8d3/0x1200 kernel/workqueue.c:2272
worker_thread+0x9c/0x1090 kernel/workqueue.c:2418
kthread+0x303/0x410 kernel/kthread.c:292
ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:296
The mptcp_worker tries to update the MPTCP retransmission timer
even if such timer is not currently scheduled.
The mptcp_rtx_head() return value is bogus: we can have enqueued
data not yet transmitted. The above may additionally cause spurious,
unneeded MPTCP-level retransmissions.
Fix the issue adding an explicit clearing of the rtx queue before
trying to retransmit and checking for unacked data.
Additionally drop an unneeded timer stop call and the unused
mptcp_rtx_tail() helper.
Reported-by: Christoph Paasch <cpaasch@apple.com>
Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
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>
The current mptcp_poll() implementation gives unexpected
results after shutdown(SEND_SHUTDOWN) and when the msk
status is TCP_CLOSE.
Set the correct mask.
Fixes: 8edf08649e ("mptcp: rework poll+nospace handling")
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>
Currently all errors received on msk subflows are ignored.
We need to catch at least the errors on connect() and
on fallback sockets.
Use a custom sk_error_report callback at subflow level,
and do the real action under the msk socket lock - via
the usual sock_owned_by_user()/release_callback() schema.
Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
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>
Add a few assertions to make sure functions are called with the needed
locks held.
Two functions gain might_sleep annotations because they contain
conditional calls to functions that sleep.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch creates a listening socket when an address with a port-number
is added by PM netlink. Then binds the new port to the socket, and
listens for new connections.
When the address is removed or the addresses are flushed by PM netlink,
release the listening socket.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On MPTCP-level ack reception, the packet scheduler
may select a subflow other then the current one.
Prior to this commit we rely on the workqueue to trigger
action on such subflow.
This changeset introduces an infrastructure that allows
any MPTCP subflow to schedule actions (MPTCP xmit) on
others subflows without resorting to (multiple) process
reschedule.
A dummy NAPI instance is used instead. When MPTCP needs to
trigger action an a different subflow, it enqueues the target
subflow on the NAPI backlog and schedule such instance as needed.
The dummy NAPI poll method walks the sockets backlog and tries
to acquire the (BH) socket lock on each of them. If the socket
is owned by the user space, the action will be completed by
the sock release cb, otherwise push is started.
This change leverages the delegated action infrastructure
to avoid invoking the MPTCP worker to spool the pending data,
when the packet scheduler picks a subflow other then the one
currently processing the incoming MPTCP-level ack.
Additionally we further refine the subflow selection
invoking the packet scheduler for each chunk of data
even inside __mptcp_subflow_push_pending().
v1 -> v2:
- fix possible UaF at shutdown time, resetting sock ops
after removing the ulp context
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Otherwise the packet scheduler policy will not be
enforced when pushing pending data at MPTCP-level
ack reception time.
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The current packet scheduler can enqueue up to sndbuf
data on each subflow. If the send buffer is large and
the subflows are not symmetric, this could lead to
suboptimal aggregate bandwidth utilization.
Limit the amount of queued data to the maximum send
window.
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After commit 6e628cd3a8 ("mptcp: use mptcp release_cb for
delayed tasks"), MPTCP never sets the flag bit SOCK_NOSPACE
on its subflow. As a side effect, autotune never takes place,
as it happens inside tcp_new_space(), which in turn is called
only when the mentioned bit is set.
Let's sendmsg() set the subflows NOSPACE bit when looking for
more memory and use the subflow write_space callback to propagate
the snd buf update and wake-up the user-space.
Additionally, this allows dropping a bunch of duplicate code and
makes the SNDBUF_LIMITED chrono relevant again for MPTCP subflows.
Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently, incoming subflows link to the parent socket,
while outgoing ones link to a per subflow socket. The latter
is not really needed, except at the initial connect() time and
for the first subflow.
Always graft the outgoing subflow to the parent socket and
free the unneeded ones early.
This allows some code cleanup, reduces the amount of memory
used and will simplify the next patch
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tcp_disconnect() expects the caller acquires the sock lock,
but mptcp_disconnect() is not doing that. Add the missing
required lock.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Fixes: 76e2a55d16 ("mptcp: better msk-level shutdown.")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/f818e82b58a556feeb71dcccc8bf1c87aafc6175.1610638176.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Instead of re-implementing most of inet_shutdown, re-use
such helper, and implement the MPTCP-specific bits at the
'proto' level.
The msk-level disconnect() can now be invoked, lets provide a
suitable implementation.
As a side effect, this fixes bad state management for listener
sockets. The latter could lead to division by 0 oops since
commit ea4ca586b1 ("mptcp: refine MPTCP-level ack scheduling").
Fixes: 43b54c6ee3 ("mptcp: Use full MPTCP-level disconnect state machine")
Fixes: ea4ca586b1 ("mptcp: refine MPTCP-level ack scheduling")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Syzkaller found a way to trigger division by zero
in mptcp_subflow_cleanup_rbuf().
The current checks implemented into tcp_can_send_ack()
are too week, let's be more accurate.
Reported-by: Christoph Paasch <cpaasch@apple.com>
Fixes: ea4ca586b1 ("mptcp: refine MPTCP-level ack scheduling")
Fixes: fd8976790a ("mptcp: be careful on MPTCP-level ack.")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When sendmsg() needs to wait for memory, the pending data
is not updated. That causes a drift in forward memory allocation,
leading to stall and/or warnings at socket close time.
This change addresses the above issue moving the pending data
counter update inside the sendmsg() main loop.
Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When multiple subflows are active, we can receive a
window update on subflow with no write space available.
MPTCP will try to push frames on such subflow and will
fail. Pending frames will be pushed only after receiving
a window update on a subflow with some wspace available.
Overall the above could lead to suboptimal aggregate
bandwidth usage.
Instead, we should try to push pending frames as soon as
the subflow reaches both conditions mentioned above.
We can finally enable self-tests with asymmetric links,
as the above makes them finally pass.
Fixes: 6f8a612a33 ("mptcp: keep track of advertised windows right edge")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
MPTCP closes the subflows while holding the msk-level lock.
While acquiring the subflow socket lock we need to use the
correct nested annotation, or we can hit a lockdep splat
at runtime.
Reported-and-tested-by: Geliang Tang <geliangtang@gmail.com>
Fixes: e16163b6e2 ("mptcp: refactor shutdown and close")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
