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* mptcp: fix bogus sendmsg() return code under pressurePaolo Abeni2020-08-041-2/+1
| | | | | | | | | | | | | | | In case of memory pressure, mptcp_sendmsg() may call sk_stream_wait_memory() after succesfully xmitting some bytes. If the latter fails we currently return to the user-space the error code, ignoring the succeful xmit. Address the issue always checking for the xmitted bytes before mptcp_sendmsg() completes. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* mptcp: use mptcp_for_each_subflow in mptcp_stream_acceptGeliang Tang2020-08-041-1/+1
| | | | | | | | | Use mptcp_for_each_subflow in mptcp_stream_accept instead of open-coding. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller2020-08-021-1/+1
|\ | | | | | | | | | | | | Resolved kernel/bpf/btf.c using instructions from merge commit 69138b34a7248d2396ab85c8652e20c0c39beaba Signed-off-by: David S. Miller <davem@davemloft.net>
| * mptcp: fix joined subflows with unblocking skMatthieu Baerts2020-07-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unblocking sockets used for outgoing connections were not containing inet info about the initial connection due to a typo there: the value of "err" variable is negative in the kernelspace. This fixes the creation of additional subflows where the remote port has to be reused if the other host didn't announce another one. This also fixes inet_diag showing blank info about MPTCP sockets from unblocking sockets doing a connect(). Fixes: 41be81a8d3d0 ("mptcp: fix unblocking connect()") Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Safely store sequence number when sending dataMat Martineau2020-07-291-1/+1
| | | | | | | | | | | | | | | | The MPTCP socket's write_seq member can be read without the msk lock held, so use WRITE_ONCE() to store it. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Safely read sequence number when lock isn't heldMat Martineau2020-07-291-1/+1
| | | | | | | | | | | | | | | | The MPTCP socket's write_seq member should be read with READ_ONCE() when the msk lock is not held. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Use full MPTCP-level disconnect state machineMat Martineau2020-07-291-14/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RFC 8684 appendix D describes the connection state machine for MPTCP. This patch implements the DATA_FIN / DATA_ACK exchanges and MPTCP-level socket state changes described in that appendix, rather than simply sending DATA_FIN along with TCP FIN when disconnecting subflows. DATA_FIN is now sent and acknowledged before shutting down the subflows. Received DATA_FIN information (if not part of a data packet) is written to the MPTCP socket when the incoming DSS option is parsed by the subflow, and the MPTCP worker is scheduled to process the flag. DATA_FIN received as part of a full DSS mapping will be handled when the mapping is processed. The DATA_FIN is acknowledged by the worker if the reader is caught up. If there is still data to be moved to the MPTCP-level queue, ack_seq will be incremented to account for the DATA_FIN when it reaches the end of the stream and a DATA_ACK will be sent to the peer. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Add helper to process acks of DATA_FINMat Martineau2020-07-291-8/+46
| | | | | | | | | | | | | | | | | | After DATA_FIN has been sent, the peer will acknowledge it. An ack of the relevant MPTCP-level sequence number will update the MPTCP connection state appropriately. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Add mptcp_close_state() helperMat Martineau2020-07-291-0/+27
| | | | | | | | | | | | | | | | This will be used to transition to the appropriate state on close and determine if a DATA_FIN needs to be sent for that state transition. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Track received DATA_FIN sequence number and add related helpersMat Martineau2020-07-291-10/+96
| | | | | | | | | | | | | | | | | | | | | | Incoming DATA_FIN headers need to propagate the presence of the DATA_FIN bit and the associated sequence number to the MPTCP layer, even when arriving on a bare ACK that does not get added to the receive queue. Add structure members to store the DATA_FIN information and helpers to set and check those values. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Use MPTCP-level flag for sending DATA_FINMat Martineau2020-07-291-16/+5
| | | | | | | | | | | | | | | | Since DATA_FIN information is the same for every subflow, store it only in the mptcp_sock. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Remove outdated and incorrect commentMat Martineau2020-07-291-1/+0
| | | | | | | | | | | | | | | | mptcp_close() acquires the msk lock, so it clearly should not be held before the function is called. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: Return EPIPE if sending is shut down during a sendmsgMat Martineau2020-07-291-0/+5
| | | | | | | | | | | | | | | | A MPTCP socket where sending has been shut down should not attempt to send additional data, since DATA_FIN has already been sent. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: pass a sockptr_t into ->setsockoptChristoph Hellwig2020-07-251-7/+5
| | | | | | | | | | | | | | | | | | | | | | Rework the remaining setsockopt code to pass a sockptr_t instead of a plain user pointer. This removes the last remaining set_fs(KERNEL_DS) outside of architecture specific code. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154] Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: switch sock_set_timeout to sockptr_tChristoph Hellwig2020-07-251-2/+4
| | | | | | | | | | | | | | | | | | Pass a sockptr_t to prepare for set_fs-less handling of the kernel pointer from bpf-cgroup. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: explicitly track the fully established statusPaolo Abeni2020-07-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently accepted msk sockets become established only after accept() returns the new sk to user-space. As MP_JOIN request are refused as per RFC spec on non fully established socket, the above causes mp_join self-tests instabilities. This change lets the msk entering the established status as soon as it receives the 3rd ack and propagates the first subflow fully established status on the msk socket. Finally we can change the subflow acceptance condition to take in account both the sock state and the msk fully established flag. Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: mark as fallback even early onesPaolo Abeni2020-07-231-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the unlikely event of a failure at connect time, we currently clear the request_mptcp flag - so that the MPC handshake is not started at all, but the msk is not explicitly marked as fallback. This would lead to later insertion of wrong DSS options in the xmitted packets, in violation of RFC specs and possibly fooling the peer. Fixes: e1ff9e82e2ea ("net: mptcp: improve fallback to TCP") Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: avoid data corruption on reinsertPaolo Abeni2020-07-231-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | When updating a partially acked data fragment, we actually corrupt it. This is irrelevant till we send data on a single subflow, as retransmitted data, if any are discarded by the peer as duplicate, but it will cause data corruption as soon as we will start creating non backup subflows. Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | subflow: always init 'rel_write_seq'Paolo Abeni2020-07-231-1/+0
| | | | | | | | | | | | | | | | | | | | | | Currently we do not init the subflow write sequence for MP_JOIN subflows. This will cause bad mapping being generated as soon as we will use non backup subflow. Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: remove compat_sock_common_{get,set}sockoptChristoph Hellwig2020-07-201-6/+0
| | | | | | | | | | | | | | | | | | | | | | Add the compat handling to sock_common_{get,set}sockopt instead, keyed of in_compat_syscall(). This allow to remove the now unused ->compat_{get,set}sockopt methods from struct proto_ops. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: use mptcp worker for path managementFlorian Westphal2020-07-071-1/+26
| | | | | | | | | | | | | | | | | | | | We can re-use the existing work queue to handle path management instead of a dedicated work queue. Just move pm_worker to protocol.c, call it from the mptcp worker and get rid of the msk lock (already held). Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: support IPV6_V6ONLY setsockoptFlorian Westphal2020-07-051-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | Without this, Opensshd fails to open an ipv6 socket listening socket: error: setsockopt IPV6_V6ONLY: Operation not supported error: Bind to port 22 on :: failed: Address already in use. Opensshd opens an ipv4 and and ipv6 listening socket, but because IPV6_V6ONLY setsockopt fails, the port number is already in use. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: add REUSEADDR/REUSEPORT supportFlorian Westphal2020-07-051-1/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This will e.g. make 'sshd restart' work when MPTCP is used, as we will now set this option on the listener socket instead of only the mptcp socket (where it has no effect). We still need to copy the setting to the master socket so that a subsequent getsockopt() returns the expected value. Reported-by: Christoph Paasch <cpaasch@apple.com> Suggested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: use mptcp setsockopt function for SOL_SOCKET on mptcp socketsFlorian Westphal2020-07-051-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | setsockopt(mptcp_fd, SOL_SOCKET, ...)... appears to work (returns 0), but it has no effect -- this is because the MPTCP layer never has a chance to copy the settings to the subflow socket. Skip the generic handling for the mptcp case and instead call the mptcp specific handler instead for SOL_SOCKET too. Next patch adds more specific handling for SOL_SOCKET to mptcp. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: add receive buffer auto-tuningFlorian Westphal2020-07-021-7/+116
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When mptcp is used, userspace doesn't read from the tcp (subflow) socket but from the parent (mptcp) socket receive queue. skbs are moved from the subflow socket to the mptcp rx queue either from 'data_ready' callback (if mptcp socket can be locked), a work queue, or the socket receive function. This means tcp_rcv_space_adjust() is never called and thus no receive buffer size auto-tuning is done. An earlier (not merged) patch added tcp_rcv_space_adjust() calls to the function that moves skbs from subflow to mptcp socket. While this enabled autotuning, it also meant tuning was done even if userspace was reading the mptcp socket very slowly. This adds mptcp_rcv_space_adjust() and calls it after userspace has read data from the mptcp socket rx queue. Its very similar to tcp_rcv_space_adjust, with two differences: 1. The rtt estimate is the largest one observed on a subflow 2. The rcvbuf size and window clamp of all subflows is adjusted to the mptcp-level rcvbuf. Otherwise, we get spurious drops at tcp (subflow) socket level if the skbs are not moved to the mptcp socket fast enough. Before: time mptcp_connect.sh -t -f $((4*1024*1024)) -d 300 -l 0.01% -r 0 -e "" -m mmap [..] ns4 MPTCP -> ns3 (10.0.3.2:10108 ) MPTCP (duration 40823ms) [ OK ] ns4 MPTCP -> ns3 (10.0.3.2:10109 ) TCP (duration 23119ms) [ OK ] ns4 TCP -> ns3 (10.0.3.2:10110 ) MPTCP (duration 5421ms) [ OK ] ns4 MPTCP -> ns3 (dead:beef:3::2:10111) MPTCP (duration 41446ms) [ OK ] ns4 MPTCP -> ns3 (dead:beef:3::2:10112) TCP (duration 23427ms) [ OK ] ns4 TCP -> ns3 (dead:beef:3::2:10113) MPTCP (duration 5426ms) [ OK ] Time: 1396 seconds After: ns4 MPTCP -> ns3 (10.0.3.2:10108 ) MPTCP (duration 5417ms) [ OK ] ns4 MPTCP -> ns3 (10.0.3.2:10109 ) TCP (duration 5427ms) [ OK ] ns4 TCP -> ns3 (10.0.3.2:10110 ) MPTCP (duration 5422ms) [ OK ] ns4 MPTCP -> ns3 (dead:beef:3::2:10111) MPTCP (duration 5415ms) [ OK ] ns4 MPTCP -> ns3 (dead:beef:3::2:10112) TCP (duration 5422ms) [ OK ] ns4 TCP -> ns3 (dead:beef:3::2:10113) MPTCP (duration 5423ms) [ OK ] Time: 296 seconds Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: close poll() racesPaolo Abeni2020-06-301-5/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | mptcp_poll always return POLLOUT for unblocking connect(), ensure that the socket is a suitable state. The MPTCP_DATA_READY bit is never cleared on accept: ensure we don't leave mptcp_accept() with an empty accept queue and such bit set. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: __mptcp_tcp_fallback() returns a struct sockPaolo Abeni2020-06-301-12/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently __mptcp_tcp_fallback() always return NULL on incoming connections, because MPTCP does not create the additional socket for the first subflow. Since the previous commit no __mptcp_tcp_fallback() caller needs a struct socket, so let __mptcp_tcp_fallback() return the first subflow sock and cope correctly even with incoming connections. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: create first subflow at msk creation timePaolo Abeni2020-06-301-33/+20
| | | | | | | | | | | | | | | | | | This cleans the code a bit and makes the behavior more consistent. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: check for plain TCP sock at accept timePaolo Abeni2020-06-301-62/+7
| | | | | | | | | | | | | | | | | | | | This cleanup the code a bit and avoid corrupted states on weird syscall sequence (accept(), connect()). Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: mptcp: improve fallback to TCPDavide Caratti2020-06-301-72/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Keep using MPTCP sockets and a use "dummy mapping" in case of fallback to regular TCP. When fallback is triggered, skip addition of the MPTCP option on send. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/11 Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/22 Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: refactor token containerPaolo Abeni2020-06-271-19/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the radix tree with a hash table allocated at boot time. The radix tree has some shortcoming: a single lock is contented by all the mptcp operation, the lookup currently use such lock, and traversing all the items would require a lock, too. With hash table instead we trade a little memory to address all the above - a per bucket lock is used. To hash the MPTCP sockets, we re-use the msk' sk_node entry: the MPTCP sockets are never hashed by the stack. Replace the existing hash proto callbacks with a dummy implementation, annotating the above constraint. Additionally refactor the token creation to code to: - limit the number of consecutive attempts to a fixed maximum. Hitting a hash bucket with a long chain is considered a failed attempt - accept() no longer can fail to token management. - if token creation fails at connect() time, we do fallback to TCP (before the connection was closed) v1 -> v2: - fix "no newline at end of file" - Jakub 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>
* | mptcp: add __init annotation on setup functionsPaolo Abeni2020-06-271-2/+2
|/ | | | | | | | | Add the missing annotation in some setup-only functions. 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>
* mptcp: fix races between shutdown and recvmsgPaolo Abeni2020-06-101-21/+24
| | | | | | | | | | | | | | | | The msk sk_shutdown flag is set by a workqueue, possibly introducing some delay in user-space notification. If the last subflow carries some data with the fin packet, the user space can wake-up before RCV_SHUTDOWN is set. If it executes unblocking recvmsg(), it may return with an error instead of eof. Address the issue explicitly checking for eof in recvmsg(), when no data is found. Fixes: 59832e246515 ("mptcp: subflow: check parent mptcp socket on subflow state change") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller2020-06-011-19/+48
|\ | | | | | | | | | | | | | | | | | | | | | | | | xdp_umem.c had overlapping changes between the 64-bit math fix for the calculation of npgs and the removal of the zerocopy memory type which got rid of the chunk_size_nohdr member. The mlx5 Kconfig conflict is a case where we just take the net-next copy of the Kconfig entry dependency as it takes on the ESWITCH dependency by one level of indirection which is what the 'net' conflicting change is trying to ensure. Signed-off-by: David S. Miller <davem@davemloft.net>
| * mptcp: remove msk from the token container at destruction time.Paolo Abeni2020-05-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we remote the msk from the token container only via mptcp_close(). The MPTCP master socket can be destroyed also via other paths (e.g. if not yet accepted, when shutting down the listener socket). When we hit the latter scenario, dangling msk references are left into the token container, leading to memory corruption and/or UaF. This change addresses the issue by moving the token removal into the msk destructor. Fixes: 79c0949e9a09 ("mptcp: Add key generation and token tree") 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>
| * mptcp: fix race between MP_JOIN and closePaolo Abeni2020-05-311-15/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a MP_JOIN subflow completes the 3whs while another CPU is closing the master msk, we can hit the following race: CPU1 CPU2 close() mptcp_close subflow_syn_recv_sock mptcp_token_get_sock mptcp_finish_join inet_sk_state_load mptcp_token_destroy inet_sk_state_store(TCP_CLOSE) __mptcp_flush_join_list() mptcp_sock_graft list_add_tail sk_common_release sock_orphan() <socket free> The MP_JOIN socket will be leaked. Additionally we can hit UaF for the msk 'struct socket' referenced via the 'conn' field. This change try to address the issue introducing some synchronization between the MP_JOIN 3whs and mptcp_close via the join_list spinlock. If we detect the msk is closing the MP_JOIN socket is closed, too. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") 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>
| * mptcp: fix unblocking connect()Paolo Abeni2020-05-311-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently unblocking connect() on MPTCP sockets fails frequently. If mptcp_stream_connect() is invoked to complete a previously attempted unblocking connection, it will still try to create the first subflow via __mptcp_socket_create(). If the 3whs is completed and the 'can_ack' flag is already set, the latter will fail with -EINVAL. This change addresses the issue checking for pending connect and delegating the completion to the first subflow. Additionally do msk addresses and sk_state changes only when needed. Fixes: 2303f994b3e1 ("mptcp: Associate MPTCP context with TCP socket") 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>
| * mptcp: avoid NULL-ptr derefence on fallbackPaolo Abeni2020-05-271-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the MPTCP receive path we must cope with TCP fallback on blocking recvmsg(). Currently in such code path we detect the fallback condition, but we don't fetch the struct socket required for fallback. The above allowed syzkaller to trigger a NULL pointer dereference: general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] CPU: 1 PID: 7226 Comm: syz-executor523 Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:sock_recvmsg_nosec net/socket.c:886 [inline] RIP: 0010:sock_recvmsg+0x92/0x110 net/socket.c:904 Code: 5b 41 5c 41 5d 41 5e 41 5f 5d c3 44 89 6c 24 04 e8 53 18 1d fb 4d 8d 6f 20 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 20 12 5b fb bd a0 00 00 00 49 03 6d RSP: 0018:ffffc90001077b98 EFLAGS: 00010202 RAX: 0000000000000004 RBX: ffffc90001077dc0 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff86565e59 R09: ffffed10115afeaa R10: ffffed10115afeaa R11: 0000000000000000 R12: 1ffff9200020efbc R13: 0000000000000020 R14: ffffc90001077de0 R15: 0000000000000000 FS: 00007fc6a3abe700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004d0050 CR3: 00000000969f0000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mptcp_recvmsg+0x18d5/0x19b0 net/mptcp/protocol.c:891 inet_recvmsg+0xf6/0x1d0 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:886 [inline] sock_recvmsg net/socket.c:904 [inline] __sys_recvfrom+0x2f3/0x470 net/socket.c:2057 __do_sys_recvfrom net/socket.c:2075 [inline] __se_sys_recvfrom net/socket.c:2071 [inline] __x64_sys_recvfrom+0xda/0xf0 net/socket.c:2071 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Address the issue initializing the struct socket reference before entering the fallback code. Reported-and-tested-by: syzbot+c6bfc3db991edc918432@syzkaller.appspotmail.com Suggested-by: Ondrej Mosnacek <omosnace@redhat.com> Fixes: 8ab183deb26a ("mptcp: cope with later TCP fallback") 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>
* | mptcp: attempt coalescing when moving skbs to mptcp rx queueFlorian Westphal2020-05-271-2/+19
| | | | | | | | | | | | | | | | | | | | | | | | We can try to coalesce skbs we take from the subflows rx queue with the tail of the mptcp rx queue. If successful, the skb head can be discarded early. We can also free the skb extensions, we do not access them after this. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: move SIOCADDRT and SIOCDELRT handling into ->compat_ioctlChristoph Hellwig2020-05-191-0/+1
| | | | | | | | | | | | | | | | To prepare removing the global routing_ioctl hack start lifting the code into a newly added ipv6 ->compat_ioctl handler. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: allow __skb_ext_alloc to sleepFlorian Westphal2020-05-171-1/+3
| | | | | | | | | | | | | | | | | | mptcp calls this from the transmit side, from process context. Allow a sleeping allocation instead of unconditional GFP_ATOMIC. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: remove inner wait loop from mptcp_sendmsg_fragFlorian Westphal2020-05-171-14/+0
| | | | | | | | | | | | | | | | | | | | | | previous patches made sure we only call into this function when these prerequisites are met, so no need to wait on the subflow socket anymore. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/7 Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: fill skb page frag cache outside of mptcp_sendmsg_fragFlorian Westphal2020-05-171-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The mptcp_sendmsg_frag helper contains a loop that will wait on the subflow sk. It seems preferrable to only wait in mptcp_sendmsg() when blocking io is requested. mptcp_sendmsg already has such a wait loop that is used when no subflow socket is available for transmission. This is another preparation patch that makes sure we call mptcp_sendmsg_frag only if the page frag cache has been refilled. Followup patch will remove the wait loop from mptcp_sendmsg_frag(). The retransmit worker doesn't need to do this refill as it won't transmit new mptcp-level data. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: fill skb extension cache outside of mptcp_sendmsg_fragFlorian Westphal2020-05-171-4/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The mptcp_sendmsg_frag helper contains a loop that will wait on the subflow sk. It seems preferrable to only wait in mptcp_sendmsg() when blocking io is requested. mptcp_sendmsg already has such a wait loop that is used when no subflow socket is available for transmission. This is a preparation patch that makes sure we call mptcp_sendmsg_frag only if a skb extension has been allocated. Moreover, such allocation currently uses GFP_ATOMIC while it could use sleeping allocation instead. Followup patches will remove the wait loop from mptcp_sendmsg_frag() and will allow to do a sleeping allocation for the extension. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: avoid blocking in tcp_sendpagesFlorian Westphal2020-05-171-3/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The transmit loop continues to xmit new data until an error is returned or all data was transmitted. For the blocking i/o case, this means that tcp_sendpages() may block on the subflow until more space becomes available, i.e. we end up sleeping with the mptcp socket lock held. Instead we should check if a different subflow is ready to be used. This restarts the subflow sk lookup when the tx operation succeeded and the tcp subflow can't accept more data or if tcp_sendpages indicates -EAGAIN on a blocking mptcp socket. In that case we also need to set the NOSPACE bit to make sure we get notified once memory becomes available. In case all subflows are busy, the existing logic will wait until a subflow is ready, releasing the mptcp socket lock while doing so. The mptcp worker already sets DONTWAIT, so no need to make changes there. v2: * set NOSPACE bit * add a comment to clarify that mptcp-sk sndbuf limits need to be checked as well. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: break and restart in case mptcp sndbuf is fullFlorian Westphal2020-05-171-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Its not enough to check for available tcp send space. We also hold on to transmitted data for mptcp-level retransmits. Right now we will send more and more data if the peer can ack data at the tcp level fast enough, since that frees up tcp send buffer space. But we also need to check that data was acked and reclaimed at the mptcp level. Therefore add needed check in mptcp_sendmsg, flush tcp data and wait until more mptcp snd space becomes available if we are over the limit. Before we wait for more data, also make sure we start the retransmit timer if we ran out of sndbuf space. Otherwise there is a very small chance that we wait forever: * receiver is waiting for data * sender is blocked because mptcp socket buffer is full * at tcp level, all data was acked * mptcp-level snd_una was not updated, because last ack that acknowledged the last data packet carried an older MPTCP-ack. Restarting the retransmit timer avoids this problem: if TCP subflow is idle, data is retransmitted from the RTX queue. New data will make the peer send a new, updated MPTCP-Ack. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: move common nospace-pattern to a helperFlorian Westphal2020-05-171-14/+13
| | | | | | | | | | | | | | | | | | Paolo noticed that ssk_check_wmem() has same pattern, so add/use common helper for both places. Suggested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller2020-05-151-0/+2
|\| | | | | | | | | | | | | | | | | | | Move the bpf verifier trace check into the new switch statement in HEAD. Resolve the overlapping changes in hinic, where bug fixes overlap the addition of VF support. Signed-off-by: David S. Miller <davem@davemloft.net>
| * mptcp: Initialize map_seq upon subflow establishmentChristoph Paasch2020-05-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the other MPTCP-peer uses 32-bit data-sequence numbers, we rely on map_seq to indicate how to expand to a 64-bit data-sequence number in expand_seq() when receiving data. For new subflows, this field is not initialized, thus results in an "invalid" mapping being discarded. Fix this by initializing map_seq upon subflow establishment time. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | mptcp: add new sock flag to deal with join subflowsPaolo Abeni2020-05-151-7/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MP_JOIN subflows must not land into the accept queue. Currently tcp_check_req() calls an mptcp specific helper to detect such scenario. Such helper leverages the subflow context to check for MP_JOIN subflows. We need to deal also with MP JOIN failures, even when the subflow context is not available due allocation failure. A possible solution would be changing the syn_recv_sock() signature to allow returning a more descriptive action/ error code and deal with that in tcp_check_req(). Since the above need is MPTCP specific, this patch instead uses a TCP request socket hole to add a MPTCP specific flag. Such flag is used by the MPTCP syn_recv_sock() to tell tcp_check_req() how to deal with the request socket. This change is a no-op for !MPTCP build, and makes the MPTCP code simpler. It allows also the next patch to deal correctly with MP JOIN failure. v1 -> v2: - be more conservative on drop_req initialization (Mat) RFC -> v1: - move the drop_req bit inside tcp_request_sock (Eric) Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Reviewed-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>