| Age | Commit message (Collapse) | Author |
|---|
|
Send timely MPTCP-level ack is somewhat difficult when
the insertion into the msk receive level is performed
by the worker.
It needs TCP-level dup-ack to notify the MPTCP-level
ack_seq increase, as both the TCP-level ack seq and the
rcv window are unchanged.
We can actually avoid processing incoming data with the
worker, and let the subflow or recevmsg() send ack as needed.
When recvmsg() moves the skbs inside the msk receive queue,
the msk space is still unchanged, so tcp_cleanup_rbuf() could
end-up skipping TCP-level ack generation. Anyway, when
__mptcp_move_skbs() is invoked, a known amount of bytes is
going to be consumed soon: we update rcv wnd computation taking
them in account.
Additionally we need to explicitly trigger tcp_cleanup_rbuf()
when recvmsg() consumes a significant amount of the receive buffer.
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>
|
|
This will simplify all operation dealing with subflows
before accept time (e.g. data fin processing, add_addr).
The join list is already flushed by mptcp_stream_accept()
before returning the newly created msk to the user space.
This also fixes an potential bug present into the old code:
conn_list was manipulated without helding the msk lock
in mptcp_stream_accept().
Tested-by: Geliang Tang <geliangtang@gmail.com>
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>
|
|
Currently <crypto/sha.h> contains declarations for both SHA-1 and SHA-2,
and <crypto/sha3.h> contains declarations for SHA-3.
This organization is inconsistent, but more importantly SHA-1 is no
longer considered to be cryptographically secure. So to the extent
possible, SHA-1 shouldn't be grouped together with any of the other SHA
versions, and usage of it should be phased out.
Therefore, split <crypto/sha.h> into two headers <crypto/sha1.h> and
<crypto/sha2.h>, and make everyone explicitly specify whether they want
the declarations for SHA-1, SHA-2, or both.
This avoids making the SHA-1 declarations visible to files that don't
want anything to do with SHA-1. It also prepares for potentially moving
sha1.h into a new insecure/ or dangerous/ directory.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
|
|
MPTCP maintains a status bit, MPTCP_SEND_SPACE, that is set when at
least one subflow and the mptcp socket itself are writeable.
mptcp_poll returns EPOLLOUT if the bit is set.
mptcp_sendmsg makes sure MPTCP_SEND_SPACE gets cleared when last write
has used up all subflows or the mptcp socket wmem.
This reworks nospace handling as follows:
MPTCP_SEND_SPACE is replaced with MPTCP_NOSPACE, i.e. inverted meaning.
This bit is set when the mptcp socket is not writeable.
The mptcp-level ack path schedule will then schedule the mptcp worker
to allow it to free already-acked data (and reduce wmem usage).
This will then wake userspace processes that wait for a POLLOUT event.
sendmsg will set MPTCP_NOSPACE only when it has to wait for more
wmem (blocking I/O case).
poll path will set MPTCP_NOSPACE in case the mptcp socket is
not writeable.
Normal tcp-level notification (SOCK_NOSPACE) is only enabled
in case the subflow socket has no available wmem.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
We must not close the subflows before all the MPTCP level
data, comprising the DATA_FIN has been acked at the MPTCP
level, otherwise we could be unable to retransmit as needed.
__mptcp_wr_shutdown() shutdown is responsible to check for the
correct status and close all subflows. Is called by the output
path after spooling any data and at shutdown/close time.
In a similar way, __mptcp_destroy_sock() is responsible to clean-up
the MPTCP level status, and is called when the msk transition
to TCP_CLOSE.
The protocol level close() does not force anymore the TCP_CLOSE
status, but orphan the msk socket and all the subflows.
Orphaned msk sockets are forciby closed after a timeout or
when all MPTCP-level data is acked.
There is a caveat about keeping the orphaned subflows around:
the TCP stack can asynchronusly call tcp_cleanup_ulp() on them via
tcp_close(). To prevent accessing freed memory on later MPTCP
level operations, the msk acquires a reference to each subflow
socket and prevent subflow_ulp_release() from releasing the
subflow context before __mptcp_destroy_sock().
The additional subflow references are released by __mptcp_done()
and the async ULP release is detected checking ULP ops. If such
field has been already cleared by the ULP release path, the
dangling context is freed directly by __mptcp_done().
Co-developed-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Minor conflicts in net/mptcp/protocol.h and
tools/testing/selftests/net/Makefile.
In both cases code was added on both sides in the same place
so just keep both.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
The msk can close MP_JOIN subflows if the initial handshake
fails. Currently such subflows are kept alive in the
conn_list until the msk itself is closed.
Beyond the wasted memory, we could end-up sending the
DATA_FIN and the DATA_FIN ack on such socket, even after a
reset.
Fixes: 43b54c6ee382 ("mptcp: Use full MPTCP-level disconnect state machine")
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>
|
|
Additional/MP_JOIN subflows that do not pass some initial handshake
tests currently causes fallback to TCP. That is an RFC violation:
we should instead reset the subflow and leave the the msk untouched.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/91
Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests")
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>
|
|
using packetdrill it's possible to observe the same MPTCP DSN being acked
by different subflows with DACK4 and DACK8. This is in contrast with what
specified in RFC8684 ยง3.3.2: if an MPTCP endpoint transmits a 64-bit wide
DSN, it MUST be acknowledged with a 64-bit wide DACK. Fix 'use_64bit_ack'
variable to make it a property of MPTCP sockets, not TCP subflows.
Fixes: a0c1d0eafd1e ("mptcp: Use 32-bit DATA_ACK when possible")
Acked-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: Jakub Kicinski <kuba@kernel.org>
|
|
Small conflict around locking in rxrpc_process_event() -
channel_lock moved to bundle in next, while state lock
needs _bh() from net.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Currently data fin on data packet are not handled properly:
the 'rcv_data_fin_seq' field is interpreted as the last
sequence number carrying a valid data, but for data fin
packet with valid maps we currently store map_seq + map_len,
that is, the next value.
The 'write_seq' fields carries instead the value subseguent
to the last valid byte, so in mptcp_write_data_fin() we
never detect correctly the last DSS map.
Fixes: 7279da6145bb ("mptcp: Use MPTCP-level flag for sending DATA_FIN")
Fixes: 1a49b2c2a501 ("mptcp: Handle incoming 32-bit DATA_FIN values")
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>
|
|
Rejecting non-native endian BTF overlapped with the addition
of support for it.
The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The peer may send a DATA_FIN mapping with either a 32-bit or 64-bit
sequence number. When a 32-bit sequence number is received for the
DATA_FIN, it must be expanded to 64 bits before comparing it to the
last acked sequence number. This expansion was missing.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/93
Fixes: 3721b9b64676 ("mptcp: Track received DATA_FIN sequence number and add related helpers")
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 helper named mptcp_destroy_common containing the
shared code between mptcp_destroy() and mptcp_sock_destruct().
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
This patch implements the remove announced addr and subflow logic in PM
netlink.
When the PM netlink removes an address, we traverse all the existing msk
sockets to find the relevant sockets.
We add a new list named anno_list in mptcp_pm_data, to record all the
announced addrs. In the traversing, we check if it has been recorded.
If it has been, we trigger the RM_ADDR signal.
We also check if this address is in conn_list. If it is, we remove the
subflow which using this local address.
Since we call mptcp_pm_free_anno_list in mptcp_destroy, we need to move
__mptcp_init_sock before the mptcp_is_enabled check in mptcp_init_sock.
Suggested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
When receiving a DATA_FIN MPTCP option on a TCP FIN packet, the DATA_FIN
information would be stored but the MPTCP worker did not get
scheduled. In turn, the MPTCP socket state would remain in
TCP_ESTABLISHED and no blocked operations would be awakened.
TCP FIN packets are seen by the MPTCP socket when moving skbs out of the
subflow receive queues, so schedule the MPTCP worker when a skb with
DATA_FIN but no data payload is moved from a subflow queue. Other cases
(DATA_FIN on a bare TCP ACK or on a packet with data payload) are
already handled.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/84
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: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Two minor conflicts:
1) net/ipv4/route.c, adding a new local variable while
moving another local variable and removing it's
initial assignment.
2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes.
One pretty prints the port mode differently, whilst another
changes the driver to try and obtain the port mode from
the port node rather than the switch node.
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Christoph reported an infinite loop in the subflow receive path
under stress condition.
If there are multiple subflows, each of them using a large send
buffer, the delta between the sequence number used by
MPTCP-level retransmission can and the current msk->ack_seq
can be greater than MAX_INT.
In the above scenario, when calling mptcp_subflow_discard_data(),
such delta will be truncated to int, and could result in a negative
number: no bytes will be dropped, and subflow_check_data_avail()
will try again to process the same packet, looping forever.
This change addresses the issue by expanding the 'limit' size to 64
bits, so that overflows are not possible anymore.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/87
Fixes: 6719331c2f73 ("mptcp: trigger msk processing even for OoO data")
Reported-and-tested-by: Christoph Paasch <cpaasch@apple.com>
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>
|
|
That is needed to let the subflows announce promptly when new
space is available in the receive buffer.
tcp_cleanup_rbuf() is currently a static function, drop the
scope modifier and add a declaration in the TCP header.
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>
|
|
Currently the 'backup' attribute of local endpoint
is ignored. Let's use it for the MP_JOIN handshake
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>
|
|
So that can be accessed easily from the subflow creation
helper. No functional change intended.
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>
|
|
Add a bunch of MPTCP mibs related to MPTCP OoO data
processing.
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>
|
|
There is no need to use the tcp_read_sock(), we can
simply drop the skb. Additionally try to look at the
next buffer for in order data.
This both simplifies the code and avoid unneeded indirect
calls.
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>
|
|
Add an RB-tree to cope with OoO (at MPTCP level) data.
__mptcp_move_skb() insert into the RB tree "future"
data, eventually coalescing skb as allowed by the
MPTCP DSN.
To simplify sequence accounting, move the DSN inside
the cb.
After successfully enqueuing in sequence data, check
if we can use any data from the RB tree.
Additionally move the data_fin check after spooling
data from the OoO tree, otherwise we could miss shutdown
events.
The RB tree code is copied as verbatim as possible
from tcp_data_queue_ofo(), with a few simplifications
due to the fact that MPTCP doesn't need to cope with
sacks. All bugs here are added by me.
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>
|
|
This is a prerequisite to allow receiving data from multiple
subflows without re-injection.
Instead of dropping the OoO - "future" data in
subflow_check_data_avail(), call into __mptcp_move_skbs()
and let the msk drop that.
To avoid code duplication factor out the mptcp_subflow_discard_data()
helper.
Note that __mptcp_move_skbs() can now find multiple subflows
with data avail (comprising to-be-discarded data), so must
update the byte counter incrementally.
v1 -> v2:
- fix checkpatch issues (unsigned -> unsigned int)
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>
|
|
This simplify mptcp_subflow_data_available() and will
made follow-up patches simpler.
Additionally remove the unneeded checks on subflow copied_seq:
we always whole skbs out of subflows.
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>
|
|
Currently, when checking for the 'msk is writable' condition, we
look at the individual subflows write space.
That works well while we send data via a single subflow, but will
not as soon as we will enable concurrent xmit on multiple subflows.
With this change msk becomes writable when the following conditions
hold:
- the socket has some free write space
- there is at least a subflow with write free space
Additionally we need to set the NOSPACE bit on all subflows
before blocking.
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>
|
|
This patch set the init remote_id to zero, otherwise it will be a random
number.
Then it added the missing subflow's remote_id setting code both in
__mptcp_subflow_connect and in subflow_ulp_clone.
Fixes: 01cacb00b35cb ("mptcp: add netlink-based PM")
Fixes: ec3edaa7ca6ce ("mptcp: Add handling of outgoing MP_JOIN requests")
Fixes: f296234c98a8f ("mptcp: Add handling of incoming MP_JOIN requests")
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
With commit b93df08ccda3 ("mptcp: explicitly track the fully
established status"), the status of unaccepted mptcp closed in
mptcp_sock_destruct() changes from TCP_SYN_RECV to TCP_ESTABLISHED.
As a result mptcp_sock_destruct() does not perform the proper
cleanup and inet_sock_destruct() will later emit a warn.
Address the issue updating the condition tested in mptcp_sock_destruct().
Also update the related comment.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/66
Reported-and-tested-by: Christoph Paasch <cpaasch@apple.com>
Fixes: b93df08ccda3 ("mptcp: explicitly track the fully established status")
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>
|
|
Nicolas reported the following oops:
[ 1521.392541] BUG: kernel NULL pointer dereference, address: 00000000000000c0
[ 1521.394189] #PF: supervisor read access in kernel mode
[ 1521.395376] #PF: error_code(0x0000) - not-present page
[ 1521.396607] PGD 0 P4D 0
[ 1521.397156] Oops: 0000 [#1] SMP PTI
[ 1521.398020] CPU: 0 PID: 22986 Comm: kworker/0:2 Not tainted 5.8.0-rc4+ #109
[ 1521.399618] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 1521.401728] Workqueue: events mptcp_worker
[ 1521.402651] RIP: 0010:mptcp_subflow_create_socket+0xf1/0x1c0
[ 1521.403954] Code: 24 08 89 44 24 04 48 8b 7a 18 e8 2a 48 d4 ff 8b 44 24 04 85 c0 75 7a 48 8b 8b 78 02 00 00 48 8b 54 24 08 48 8d bb 80 00 00 00 <48> 8b 89 c0 00 00 00 48 89 8a c0 00 00 00 48 8b 8b 78 02 00 00 8b
[ 1521.408201] RSP: 0000:ffffabc4002d3c60 EFLAGS: 00010246
[ 1521.409433] RAX: 0000000000000000 RBX: ffffa0b9ad8c9a00 RCX: 0000000000000000
[ 1521.411096] RDX: ffffa0b9ae78a300 RSI: 00000000fffffe01 RDI: ffffa0b9ad8c9a80
[ 1521.412734] RBP: ffffa0b9adff2e80 R08: ffffa0b9af02d640 R09: ffffa0b9ad923a00
[ 1521.414333] R10: ffffabc4007139f8 R11: fefefefefefefeff R12: ffffabc4002d3cb0
[ 1521.415918] R13: ffffa0b9ad91fa58 R14: ffffa0b9ad8c9f9c R15: 0000000000000000
[ 1521.417592] FS: 0000000000000000(0000) GS:ffffa0b9af000000(0000) knlGS:0000000000000000
[ 1521.419490] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1521.420839] CR2: 00000000000000c0 CR3: 000000002951e006 CR4: 0000000000160ef0
[ 1521.422511] Call Trace:
[ 1521.423103] __mptcp_subflow_connect+0x94/0x1f0
[ 1521.425376] mptcp_pm_create_subflow_or_signal_addr+0x200/0x2a0
[ 1521.426736] mptcp_worker+0x31b/0x390
[ 1521.431324] process_one_work+0x1fc/0x3f0
[ 1521.432268] worker_thread+0x2d/0x3b0
[ 1521.434197] kthread+0x117/0x130
[ 1521.435783] ret_from_fork+0x22/0x30
on some unconventional configuration.
The MPTCP protocol is trying to create a subflow for an
unaccepted server socket. That is allowed by the RFC, even
if subflow creation will likely fail.
Unaccepted sockets have still a NULL sk_socket field,
avoid the issue by failing earlier.
Reported-and-tested-by: Nicolas Rybowski <nicolas.rybowski@tessares.net>
Fixes: 7d14b0d2b9b3 ("mptcp: set correct vfs info for subflows")
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>
|
|
JOIN requests do not work in syncookie mode -- for HMAC validation, the
peers nonce and the mptcp token (to obtain the desired connection socket
the join is for) are required, but this information is only present in the
initial syn.
So either we need to drop all JOIN requests once a listening socket enters
syncookie mode, or we need to store enough state to reconstruct the request
socket later.
This adds a state table (1024 entries) to store the data present in the
MP_JOIN syn request and the random nonce used for the cookie syn/ack.
When a MP_JOIN ACK passed cookie validation, the table is consulted
to rebuild the request socket from it.
An alternate approach would be to "cancel" syn-cookie mode and force
MP_JOIN to always use a syn queue entry.
However, doing so brings the backlog over the configured queue limit.
v2: use req->syncookie, not (removed) want_cookie arg
Suggested-by: Paolo Abeni <pabeni@redhat.com>
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>
|
|
Will be used to initialize the mptcp request socket when a MP_CAPABLE
request was handled in syncookie mode, i.e. when a TCP ACK containing a
MP_CAPABLE option is a valid syncookie value.
Normally (non-cookie case), MPTCP will generate a unique 32 bit connection
ID and stores it in the MPTCP token storage to be able to retrieve the
mptcp socket for subflow joining.
In syncookie case, we do not want to store any state, so just generate the
unique ID and use it in the reply.
This means there is a small window where another connection could generate
the same token.
When Cookie ACK comes back, we check that the token has not been registered
in the mean time. If it was, the connection needs to fall back to TCP.
Changes in v2:
- use req->syncookie instead of passing 'want_cookie' arg to ->init_req()
(Eric Dumazet)
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>
|
|
syncookie code path needs to create an mptcp request sock.
Prepare for this and add mptcp prefix plus needed export of ops struct.
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>
|
|
When syncookie support is added, we will need to add a variant of
subflow_init_req() helper. It will do almost same thing except
that it will not compute/add a token to the mptcp token tree.
To avoid excess copy&paste, this commit splits away part of the
code into a new helper, __subflow_init_req, that can then be re-used
from the 'no insert' function added in a followup change.
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>
|
|
Once syncookie support is added, no state will be stored anymore when the
syn/ack is generated in syncookie mode.
When the ACK comes back, the generated key will be taken from the TCP ACK,
the token is re-generated and inserted into the token tree.
This means we can't retry with a new key when the token is already taken
in the syncookie case.
Therefore, move the retry logic to the caller to prepare for syncookie
support in mptcp.
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>
|
|
The MPTCP state machine handles disconnections on non-fallback connections,
but the mptcp_sock still needs to get notified when fallback subflows
disconnect.
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
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>
|
|
So that we can easily perform some basic PM-related
adimission checks before creating the child socket.
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>
|
|
tcp_send_active_reset() is more prone to transient errors
(memory allocation or xmit queue full): in stress conditions
the kernel may drop the egress packet, and the client will be
stuck.
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>
|
|
When syncookie are in use, the TCP stack may feed into
subflow_syn_recv_sock() plain TCP request sockets. We can't
access mptcp_subflow_request_sock-specific fields on such
sockets. Explicitly check the rsk ops to do safe accesses.
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>
|
|
The mentioned function has several unneeded branches,
handle each case - MP_CAPABLE, MP_JOIN, fallback -
under a single conditional and drop quite a bit of
duplicate code.
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>
|
|
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>
|
|
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>
|
|
since commit d47a72152097 ("mptcp: fix race in subflow_data_ready()"), it
is possible to observe a regression in MP_JOIN kselftests. For sockets in
TCP_CLOSE state, it's not sufficient to just wake up the main socket: we
also need to ensure that received data are made available to the reader.
Silence the WARN_ON_ONCE() in these cases: it preserves the syzkaller fix
and restores kselftests when they are ran as follows:
# while true; do
> make KBUILD_OUTPUT=/tmp/kselftest TARGETS=net/mptcp kselftest
> done
Reported-by: Florian Westphal <fw@strlen.de>
Fixes: d47a72152097 ("mptcp: fix race in subflow_data_ready()")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/47
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
syzkaller was able to make the kernel reach subflow_data_ready() for a
server subflow that was closed before subflow_finish_connect() completed.
In these cases we can avoid using the path for regular/fallback MPTCP
data, and just wake the main socket, to avoid the following warning:
WARNING: CPU: 0 PID: 9370 at net/mptcp/subflow.c:885
subflow_data_ready+0x1e6/0x290 net/mptcp/subflow.c:885
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 9370 Comm: syz-executor.0 Not tainted 5.7.0 #106
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xb7/0xfe lib/dump_stack.c:118
panic+0x29e/0x692 kernel/panic.c:221
__warn.cold+0x2f/0x3d kernel/panic.c:582
report_bug+0x28b/0x2f0 lib/bug.c:195
fixup_bug arch/x86/kernel/traps.c:105 [inline]
fixup_bug arch/x86/kernel/traps.c:100 [inline]
do_error_trap+0x10f/0x180 arch/x86/kernel/traps.c:197
do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:216
invalid_op+0x1e/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:subflow_data_ready+0x1e6/0x290 net/mptcp/subflow.c:885
Code: 04 02 84 c0 74 06 0f 8e 91 00 00 00 41 0f b6 5e 48 31 ff 83 e3 18
89 de e8 37 ec 3d fe 84 db 0f 85 65 ff ff ff e8 fa ea 3d fe <0f> 0b e9
59 ff ff ff e8 ee ea 3d fe 48 89 ee 4c 89 ef e8 f3 77 ff
RSP: 0018:ffff88811b2099b0 EFLAGS: 00010206
RAX: ffff888111197000 RBX: 0000000000000000 RCX: ffffffff82fbc609
RDX: 0000000000000100 RSI: ffffffff82fbc616 RDI: 0000000000000001
RBP: ffff8881111bc800 R08: ffff888111197000 R09: ffffed10222a82af
R10: ffff888111541577 R11: ffffed10222a82ae R12: 1ffff11023641336
R13: ffff888111541000 R14: ffff88810fd4ca00 R15: ffff888111541570
tcp_child_process+0x754/0x920 net/ipv4/tcp_minisocks.c:841
tcp_v4_do_rcv+0x749/0x8b0 net/ipv4/tcp_ipv4.c:1642
tcp_v4_rcv+0x2666/0x2e60 net/ipv4/tcp_ipv4.c:1999
ip_protocol_deliver_rcu+0x29/0x1f0 net/ipv4/ip_input.c:204
ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
NF_HOOK include/linux/netfilter.h:421 [inline]
ip_local_deliver+0x2da/0x390 net/ipv4/ip_input.c:252
dst_input include/net/dst.h:441 [inline]
ip_rcv_finish net/ipv4/ip_input.c:428 [inline]
ip_rcv_finish net/ipv4/ip_input.c:414 [inline]
NF_HOOK include/linux/netfilter.h:421 [inline]
ip_rcv+0xef/0x140 net/ipv4/ip_input.c:539
__netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:5268
__netif_receive_skb+0x27/0x1c0 net/core/dev.c:5382
process_backlog+0x1e5/0x6d0 net/core/dev.c:6226
napi_poll net/core/dev.c:6671 [inline]
net_rx_action+0x3e3/0xd70 net/core/dev.c:6739
__do_softirq+0x18c/0x634 kernel/softirq.c:292
do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
</IRQ>
do_softirq.part.0+0x26/0x30 kernel/softirq.c:337
do_softirq arch/x86/include/asm/preempt.h:26 [inline]
__local_bh_enable_ip+0x46/0x50 kernel/softirq.c:189
local_bh_enable include/linux/bottom_half.h:32 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline]
ip_finish_output2+0x78a/0x19c0 net/ipv4/ip_output.c:229
__ip_finish_output+0x471/0x720 net/ipv4/ip_output.c:306
dst_output include/net/dst.h:435 [inline]
ip_local_out+0x181/0x1e0 net/ipv4/ip_output.c:125
__ip_queue_xmit+0x7a1/0x14e0 net/ipv4/ip_output.c:530
__tcp_transmit_skb+0x19dc/0x35e0 net/ipv4/tcp_output.c:1238
__tcp_send_ack.part.0+0x3c2/0x5b0 net/ipv4/tcp_output.c:3785
__tcp_send_ack net/ipv4/tcp_output.c:3791 [inline]
tcp_send_ack+0x7d/0xa0 net/ipv4/tcp_output.c:3791
tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:6040 [inline]
tcp_rcv_state_process+0x36a4/0x49c2 net/ipv4/tcp_input.c:6209
tcp_v4_do_rcv+0x343/0x8b0 net/ipv4/tcp_ipv4.c:1651
sk_backlog_rcv include/net/sock.h:996 [inline]
__release_sock+0x1ad/0x310 net/core/sock.c:2548
release_sock+0x54/0x1a0 net/core/sock.c:3064
inet_wait_for_connect net/ipv4/af_inet.c:594 [inline]
__inet_stream_connect+0x57e/0xd50 net/ipv4/af_inet.c:686
inet_stream_connect+0x53/0xa0 net/ipv4/af_inet.c:725
mptcp_stream_connect+0x171/0x5f0 net/mptcp/protocol.c:1920
__sys_connect_file net/socket.c:1854 [inline]
__sys_connect+0x267/0x2f0 net/socket.c:1871
__do_sys_connect net/socket.c:1882 [inline]
__se_sys_connect net/socket.c:1879 [inline]
__x64_sys_connect+0x6f/0xb0 net/socket.c:1879
do_syscall_64+0xb7/0x3d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fb577d06469
Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89
f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01
f0 ff ff 73 01 c3 48 8b 0d ff 49 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007fb5783d5dd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 000000000068bfa0 RCX: 00007fb577d06469
RDX: 000000000000004d RSI: 0000000020000040 RDI: 0000000000000003
RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000041427c R14: 00007fb5783d65c0 R15: 0000000000000003
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/39
Reported-by: Christoph Paasch <cpaasch@apple.com>
Fixes: e1ff9e82e2ea ("net: mptcp: improve fallback to TCP")
Suggested-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>
|
|
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>
|
|
This clean-up the code a bit, reduces the number of
used hooks and indirect call requested, and allow
better error reporting from __mptcp_subflow_connect()
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>
|
|
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:
1) a WARN_ON() in subflow_data_ready() is hit
WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
[...]
CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
[...]
RIP: 0010:subflow_data_ready+0x18b/0x230
[...]
Call Trace:
tcp_data_queue+0xd2f/0x4250
tcp_rcv_state_process+0xb1c/0x49d3
tcp_v4_do_rcv+0x2bc/0x790
__release_sock+0x153/0x2d0
release_sock+0x4f/0x170
mptcp_shutdown+0x167/0x4e0
__sys_shutdown+0xe6/0x180
__x64_sys_shutdown+0x50/0x70
do_syscall_64+0x9a/0x370
entry_SYSCALL_64_after_hwframe+0x44/0xa9
2) client is stuck forever in mptcp_sendmsg() because the socket is not
TCP_ESTABLISHED
crash> bt 4847
PID: 4847 TASK: ffff88814b2fb100 CPU: 1 COMMAND: "gh35"
#0 [ffff8881376ff680] __schedule at ffffffff97248da4
#1 [ffff8881376ff778] schedule at ffffffff9724a34f
#2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
#3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
#4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
#5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
#6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
#7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
#8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
#9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
#10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
#11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
#12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
RIP: 00007f126f6956ed RSP: 00007ffc2a320278 RFLAGS: 00000217
RAX: ffffffffffffffda RBX: 0000000020000044 RCX: 00007f126f6956ed
RDX: 0000000000000004 RSI: 00000000004007b8 RDI: 0000000000000003
RBP: 00007ffc2a3202a0 R8: 0000000000400720 R9: 0000000000400720
R10: 0000000000400720 R11: 0000000000000217 R12: 00000000004004b0
R13: 00007ffc2a320380 R14: 0000000000000000 R15: 0000000000000000
ORIG_RAX: 0000000000000001 CS: 0033 SS: 002b
3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
didn't complete.
$ tcpdump -tnnr bad.pcap
IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0
force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-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>
|
|
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>
|
|
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>
|
