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author | David Howells <dhowells@redhat.com> | 2016-10-06 08:11:49 +0100 |
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committer | David Howells <dhowells@redhat.com> | 2016-10-06 08:11:49 +0100 |
commit | b3156274ca01297b861e912175820e78c9ac4d7c (patch) | |
tree | afa5a44c0f57db3ce8f442b50fd9460501d9a431 /net | |
parent | a5af7e1fc69a46f29b977fd4b570e0ac414c2338 (diff) | |
download | linux-stable-b3156274ca01297b861e912175820e78c9ac4d7c.tar.gz linux-stable-b3156274ca01297b861e912175820e78c9ac4d7c.tar.bz2 linux-stable-b3156274ca01297b861e912175820e78c9ac4d7c.zip |
rxrpc: Partially handle OpenAFS's improper termination of calls
OpenAFS doesn't always correctly terminate client calls that it makes -
this includes calls the OpenAFS servers make to the cache manager service.
It should end the client call with either:
(1) An ACK that has firstPacket set to one greater than the seq number of
the reply DATA packet with the LAST_PACKET flag set (thereby
hard-ACK'ing all packets). nAcks should be 0 and acks[] should be
empty (ie. no soft-ACKs).
(2) An ACKALL packet.
OpenAFS, though, may send an ACK packet with firstPacket set to the last
seq number or less and soft-ACKs listed for all packets up to and including
the last DATA packet.
The transmitter, however, is obliged to keep the call live and the
soft-ACK'd DATA packets around until they're hard-ACK'd as the receiver is
permitted to drop any merely soft-ACK'd packet and request retransmission
by sending an ACK packet with a NACK in it.
Further, OpenAFS will also terminate a client call by beginning the next
client call on the same connection channel. This implicitly completes the
previous call.
This patch handles implicit ACK of a call on a channel by the reception of
the first packet of the next call on that channel.
If another call doesn't come along to implicitly ACK a call, then we have
to time the call out. There are some bugs there that will be addressed in
subsequent patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'net')
-rw-r--r-- | net/rxrpc/input.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c index a6da83f036d6..44fb8d893c7d 100644 --- a/net/rxrpc/input.c +++ b/net/rxrpc/input.c @@ -939,6 +939,33 @@ static void rxrpc_input_call_packet(struct rxrpc_call *call, } /* + * Handle a new call on a channel implicitly completing the preceding call on + * that channel. + * + * TODO: If callNumber > call_id + 1, renegotiate security. + */ +static void rxrpc_input_implicit_end_call(struct rxrpc_connection *conn, + struct rxrpc_call *call) +{ + switch (call->state) { + case RXRPC_CALL_SERVER_AWAIT_ACK: + rxrpc_call_completed(call); + break; + case RXRPC_CALL_COMPLETE: + break; + default: + if (rxrpc_abort_call("IMP", call, 0, RX_CALL_DEAD, ESHUTDOWN)) { + set_bit(RXRPC_CALL_EV_ABORT, &call->events); + rxrpc_queue_call(call); + } + break; + } + + __rxrpc_disconnect_call(conn, call); + rxrpc_notify_socket(call); +} + +/* * post connection-level events to the connection * - this includes challenges, responses, some aborts and call terminal packet * retransmission. @@ -1146,6 +1173,16 @@ void rxrpc_data_ready(struct sock *udp_sk) } call = rcu_dereference(chan->call); + + if (sp->hdr.callNumber > chan->call_id) { + if (!(sp->hdr.flags & RXRPC_CLIENT_INITIATED)) { + rcu_read_unlock(); + goto reject_packet; + } + if (call) + rxrpc_input_implicit_end_call(conn, call); + call = NULL; + } } else { skew = 0; call = NULL; |