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2021-07-10mptcp: properly account bulk freed memoryPaolo Abeni1-5/+7
After commit 879526030c8b ("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: 879526030c8b ("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>
2021-06-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+5
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>
2021-06-28mptcp: fix 'masking a bool' warningMatthieu Baerts1-1/+1
Dan Carpenter reported an issue introduced in commit fde56eea01f9 ("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: fde56eea01f9 ("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>
2021-06-23mptcp: refine mptcp_cleanup_rbufPaolo Abeni1-33/+23
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>
2021-06-22mptcp: avoid race on msk state changesPaolo Abeni1-0/+5
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: 8fd738049ac3 ("mptcp: fallback in case of simultaneous connect") Fixes: c3c123d16c0e ("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>
2021-06-22mptcp: drop redundant test in move_skbs_to_msk()Paolo Abeni1-3/+0
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>
2021-06-22mptcp: don't clear MPTCP_DATA_READY in sk_wait_event()Paolo Abeni1-4/+2
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>
2021-06-22mptcp: use fast lock for subflows when possiblePaolo Abeni1-6/+9
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>
2021-06-22mptcp: drop tx skb cachePaolo Abeni1-85/+4
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>
2021-06-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-25/+27
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>
2021-06-18mptcp: tune re-injections for csum enabled modePaolo Abeni1-3/+5
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>
2021-06-18mptcp: add csum_reqd in mptcp_options_receivedGeliang Tang1-0/+2
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>
2021-06-18mptcp: generate the data checksumGeliang Tang1-1/+17
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>
2021-06-18mptcp: add csum_enabled in mptcp_sockGeliang Tang1-0/+1
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>
2021-06-11mptcp: fix soft lookup in subflow_error_report()Paolo Abeni1-0/+9
Maxim reported a soft lookup in subflow_error_report(): watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:0] RIP: 0010:native_queued_spin_lock_slowpath RSP: 0018:ffffa859c0003bc0 EFLAGS: 00000202 RAX: 0000000000000101 RBX: 0000000000000001 RCX: 0000000000000000 RDX: ffff9195c2772d88 RSI: 0000000000000000 RDI: ffff9195c2772d88 RBP: ffff9195c2772d00 R08: 00000000000067b0 R09: c6e31da9eb1e44f4 R10: ffff9195ef379700 R11: ffff9195edb50710 R12: ffff9195c2772d88 R13: ffff9195f500e3d0 R14: ffff9195ef379700 R15: ffff9195ef379700 FS: 0000000000000000(0000) GS:ffff91961f400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c000407000 CR3: 0000000002988000 CR4: 00000000000006f0 Call Trace: <IRQ> _raw_spin_lock_bh subflow_error_report mptcp_subflow_data_available __mptcp_move_skbs_from_subflow mptcp_data_ready tcp_data_queue tcp_rcv_established tcp_v4_do_rcv tcp_v4_rcv ip_protocol_deliver_rcu ip_local_deliver_finish __netif_receive_skb_one_core netif_receive_skb rtl8139_poll 8139too __napi_poll net_rx_action __do_softirq __irq_exit_rcu common_interrupt </IRQ> The calling function - mptcp_subflow_data_available() - can be invoked from different contexts: - plain ssk socket lock - ssk socket lock + mptcp_data_lock - ssk socket lock + mptcp_data_lock + msk socket lock. Since subflow_error_report() tries to acquire the mptcp_data_lock, the latter two call chains will cause soft lookup. This change addresses the issue moving the error reporting call to outer functions, where the held locks list is known and the we can acquire only the needed one. Reported-by: Maxim Galaganov <max@internet.ru> Fixes: 15cc10453398 ("mptcp: deliver ssk errors to msk") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/199 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11mptcp: wake-up readers only for in sequence dataPaolo Abeni1-21/+12
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: 648ef4b88673 ("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>
2021-06-11mptcp: try harder to borrow memory from subflow under pressurePaolo Abeni1-4/+6
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: 9c3f94e1681b ("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>
2021-06-07Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-1/+15
Bug fixes overlapping feature additions and refactoring, mostly. Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-05mptcp: receive path cmsg supportFlorian Westphal1-3/+25
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>
2021-05-28mptcp: fix sk_forward_memory corruption on retransmissionPaolo Abeni1-1/+15
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: 64b9cea7a0af ("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>
2021-05-26mptcp: avoid OOB access in setsockopt()Paolo Abeni1-3/+11
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: aa1fbd94e5c7 ("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>
2021-05-12mptcp: fix data stream corruptionPaolo Abeni1-0/+6
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: 18b683bff89d ("mptcp: queue data for mptcp level retransmission") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-2/+23
2021-04-24mptcp: add MSG_PEEK supportYonglong Li1-9/+13
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>
2021-04-24mptcp: ignore unsupported msg flagsPaolo Abeni1-4/+5
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>
2021-04-24mptcp: implement MSG_TRUNC supportPaolo Abeni1-7/+9
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>
2021-04-24mptcp: implement dummy MSG_ERRQUEUE supportPaolo Abeni1-0/+4
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>
2021-04-24mptcp: Retransmit DATA_FINMat Martineau1-2/+23
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: 43b54c6ee382 ("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>
2021-04-17mptcp: use mptcp_for_each_subflow in mptcp_closeGeliang Tang1-1/+1
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>
2021-04-17mptcp: add tracepoint in mptcp_subflow_get_sendGeliang Tang1-4/+4
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>
2021-04-17mptcp: export mptcp_subflow_activeGeliang Tang1-12/+0
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>
2021-04-17mptcp: fix format specifiers for unsigned intGeliang Tang1-2/+2
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: d9ca1de8c0cd ("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>
2021-04-17mptcp: sockopt: add TCP_CONGESTION and TCP_INFOFlorian Westphal1-0/+5
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>
2021-04-17mptcp: tag sequence_seq with socket stateFlorian Westphal1-3/+9
Paolo Abeni suggested to avoid re-syncing new subflows because they inherit options from listener. In case options were set on listener but are not set on mptcp-socket there is no need to do any synchronisation for new subflows. This change sets sockopt_seq of new mptcp sockets to the seq of the mptcp listener sock. Subflow sequence is set to the embedded tcp listener sk. Add a comment explaing why sk_state is involved in sockopt_seq generation. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-17mptcp: add skeleton to sync msk socket options to subflowsFlorian Westphal1-8/+33
Handle following cases: 1. setsockopt is called with multiple subflows. Change might have to be mirrored to all of them. This is done directly in process context/setsockopt call. 2. Outgoing subflow is created after one or several setsockopt() calls have been made. Old setsockopt changes should be synced to the new socket. 3. Incoming subflow, after setsockopt call(s). Cases 2 and 3 are handled right after the join list is spliced to the conn list. Not all sockopt values can be just be copied by value, some require helper calls. Those can acquire socket lock (which can sleep). If the join->conn list splicing is done from preemptible context, synchronization can be done right away, otherwise its deferred to work queue. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-17mptcp: move sockopt function into a new filePaolo Abeni1-120/+0
The MPTCP sockopt implementation is going to be much more big and complex soon. Let's move it to a different source file. No functional change intended. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-17mptcp: revert "mptcp: forbit mcast-related sockopt on MPTCP sockets"Matthieu Baerts1-45/+0
This change reverts commit 86581852d771 ("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>
2021-04-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-53/+47
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>
2021-04-03mptcp: add mptcp reset option supportFlorian Westphal1-3/+9
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>
2021-04-03mptcp: remove unneeded check on first subflowPaolo Abeni1-1/+1
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>
2021-04-03mptcp: add active MPC mibsPaolo Abeni1-0/+2
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>
2021-04-03mptcp: add mib for token creation fallbackPaolo Abeni1-1/+3
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>
2021-04-02mptcp: revert "mptcp: provide subflow aware release function"Paolo Abeni1-53/+2
This change reverts commit ad98dd37051e ("mptcp: provide subflow aware release function"). The latter introduced a deadlock spotted by syzkaller and is not needed anymore after the previous commit. Fixes: ad98dd37051e ("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>
2021-04-02mptcp: forbit mcast-related sockopt on MPTCP socketsPaolo Abeni1-0/+45
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: 717e79c867ca5 ("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>
2021-03-27mptcp: clean-up the rtx pathPaolo Abeni1-31/+11
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>
2021-03-13mptcp: fix bit MPTCP_PUSH_PENDING testsDan Carpenter1-2/+2
The MPTCP_PUSH_PENDING define is 6 and these tests should be testing if BIT(6) is set. Fixes: c2e6048fa1cf ("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>
2021-03-05mptcp: fix missing wakeupPaolo Abeni1-2/+8
__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: 6e628cd3a8f7 ("mptcp: use mptcp release_cb for delayed tasks") Fixes: 64b9cea7a0af ("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>
2021-03-05mptcp: fix race in release_cbPaolo Abeni1-12/+21
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: 6e628cd3a8f7 ("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>
2021-03-05mptcp: factor out __mptcp_retrans helper()Paolo Abeni1-43/+50
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>
2021-03-05mptcp: reset 'first' and ack_hint on subflow closeFlorian Westphal1-0/+9
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>