kernel/linux.git/net/rxrpc/input.c, branch v6.6.132

rxrpc: Fix call state set to not include the SERVER_SECURING state

2025-02-17T08:40:14+00:00

[ Upstream commit 41b996ce83bf944de5569d6263c8dbd5513e7ed0 ] The RXRPC_CALL_SERVER_SECURING state doesn't really belong with the other states in the call's state set as the other states govern the call's Rx/Tx phase transition and govern when packets can and can't be received or transmitted. The "Securing" state doesn't actually govern the reception of packets and would need to be split depending on whether or not we've received the last packet yet (to mirror RECV_REQUEST/ACK_REQUEST). The "Securing" state is more about whether or not we can start forwarding packets to the application as recvmsg will need to decode them and the decoding can't take place until the challenge/response exchange has completed. Fix this by removing the RXRPC_CALL_SERVER_SECURING state from the state set and, instead, using a flag, RXRPC_CALL_CONN_CHALLENGING, to track whether or not we can queue the call for reception by recvmsg() or notify the kernel app that data is ready. In the event that we've already received all the packets, the connection event handler will poke the app layer in the appropriate manner. Also there's a race whereby the app layer sees the last packet before rxrpc has managed to end the rx phase and change the state to one amenable to allowing a reply. Fix this by queuing the packet after calling rxrpc_end_rx_phase(). Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Signed-off-by: David Howells cc: Marc Dionne cc: Simon Horman cc: linux-afs@lists.infradead.org Link: https://patch.msgid.link/20250204230558.712536-2-dhowells@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rxrpc: Only transmit one ACK per jumbo packet received

2024-05-17T10:02:23+00:00

[ Upstream commit 012b7206918dcc5a4dcf1432b3e643114c95957e ] Only generate one ACK packet for all the subpackets in a jumbo packet. If we would like to generate more than one ACK, we prioritise them base on their reason code, in the order, highest first: OutOfSeq > NoSpace > ExceedsWin > Duplicate > Requested > Delay > Idle For the first four, we reference the lowest offending subpacket; for the last three, the highest. This reduces the number of ACKs we end up transmitting to one per UDP packet transmitted to reduce network loading and packet parsing. Fixes: 5d7edbc9231e ("rxrpc: Get rid of the Rx ring") Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org Reviewed-by: Jeffrey Altman > Link: https://lore.kernel.org/r/20240503150749.1001323-3-dhowells@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rxrpc: Fix congestion control algorithm

2024-05-17T10:02:23+00:00

[ Upstream commit ba4e103848d3a2a28a0445e39f4a9564187efe54 ] Make the following fixes to the congestion control algorithm: (1) Don't vary the cwnd starting value by the size of RXRPC_TX_SMSS since that's currently held constant - set to the size of a jumbo subpacket payload so that we can create jumbo packets on the fly. The current code invariably picks 3 as the starting value. Further, the starting cwnd needs to be an even number because we ack every other packet, so set it to 4. (2) Don't cut ssthresh when we see an ACK come from the peer with a receive window (rwind) less than ssthresh. ssthresh keeps track of characteristics of the connection whereas rwind may be reduced by the peer for any reason - and may be reduced to 0. Fixes: 1fc4fa2ac93d ("rxrpc: Fix congestion management") Fixes: 0851115090a3 ("rxrpc: Reduce ssthresh to peer's receive window") Signed-off-by: David Howells Suggested-by: Simon Wilkinson cc: Marc Dionne cc: linux-afs@lists.infradead.org Reviewed-by: Jeffrey Altman > Link: https://lore.kernel.org/r/20240503150749.1001323-2-dhowells@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rxrpc: Fix the names of the fields in the ACK trailer struct

2024-05-17T10:02:23+00:00

[ Upstream commit 17469ae0582aaacad36e8e858f58b86c369f21ef ] From AFS-3.3 a trailer containing extra info was added to the ACK packet format - but AF_RXRPC has the names of some of the fields mixed up compared to other AFS implementations. Rename the struct and the fields to make them match. Signed-off-by: David Howells cc: Marc Dionne cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org Stable-dep-of: ba4e103848d3 ("rxrpc: Fix congestion control algorithm") Signed-off-by: Sasha Levin

rxrpc: Fix counting of new acks and nacks

2024-02-16T18:10:50+00:00

[ Upstream commit 41b7fa157ea1c8c3a575ca7f5f32034de9bee3ae ] Fix the counting of new acks and nacks when parsing a packet - something that is used in congestion control. As the code stands, it merely notes if there are any nacks whereas what we really should do is compare the previous SACK table to the new one, assuming we get two successive ACK packets with nacks in them. However, we really don't want to do that if we can avoid it as the tables might not correspond directly as one may be shifted from the other - something that will only get harder to deal with once extended ACK tables come into full use (with a capacity of up to 8192). Instead, count the number of nacks shifted out of the old SACK, the number of nacks retained in the portion still active and the number of new acks and nacks in the new table then calculate what we need. Note this ends up a bit of an estimate as the Rx protocol allows acks to be withdrawn by the receiver and packets requested to be retransmitted. Fixes: d57a3a151660 ("rxrpc: Save last ACK's SACK table rather than marking txbufs") Signed-off-by: David Howells cc: Marc Dionne cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

rxrpc: Defer the response to a PING ACK until we've parsed it

2023-12-03T06:33:02+00:00

[ Upstream commit 1a01319feef7047aa2ba400ffa3e047776aa29ca ] Defer the generation of a PING RESPONSE ACK in response to a PING ACK until we've parsed the PING ACK so that we pick up any changes to the packet queue so that we can update ackinfo. This is also applied to an ACK generated in response to an ACK with the REQUEST_ACK flag set. Note that whilst the problem was added in commit 248f219cb8bc, it didn't really matter at that point because the ACK was proposed in softirq mode and generated asynchronously later in process context, taking the latest values at the time. But this fix is only needed since the move to parse incoming packets in an I/O thread rather than in softirq and generate the ACK at point of proposal (b0346843b1076b34a0278ff601f8f287535cb064). Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells cc: Marc Dionne cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

rxrpc: Fix RTT determination to use any ACK as a source

2023-12-03T06:33:02+00:00

[ Upstream commit 3798680f2fbbe0ca3ab6138b34e0d161c36497ee ] Fix RTT determination to be able to use any type of ACK as the response from which RTT can be calculated provided its ack.serial is non-zero and matches the serial number of an outgoing DATA or ACK packet. This shouldn't be limited to REQUESTED-type ACKs as these can have other types substituted for them for things like duplicate or out-of-order packets. Fixes: 4700c4d80b7b ("rxrpc: Fix loss of RTT samples due to interposed ACK") Signed-off-by: David Howells cc: Marc Dionne cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

rxrpc: Fix overproduction of wakeups to recvmsg()

2023-02-20T07:33:25+00:00

Fix three cases of overproduction of wakeups: (1) rxrpc_input_split_jumbo() conditionally notifies the app that there's data for recvmsg() to collect if it queues some data - and then its only caller, rxrpc_input_data(), goes and wakes up recvmsg() anyway. Fix the rxrpc_input_data() to only do the wakeup in failure cases. (2) If a DATA packet is received for a call by the I/O thread whilst recvmsg() is busy draining the call's rx queue in the app thread, the call will left on the recvmsg() queue for recvmsg() to pick up, even though there isn't any data on it. This can cause an unexpected recvmsg() with a 0 return and no MSG_EOR set after the reply has been posted to a service call. Fix this by discarding pending calls from the recvmsg() queue that don't need servicing yet. (3) Not-yet-completed calls get requeued after having data read from them, even if they have no data to read. Fix this by only requeuing them if they have data waiting on them; if they don't, the I/O thread will requeue them when data arrives or they fail. Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/3386149.1676497685@warthog.procyon.org.uk Signed-off-by: Paolo Abeni

rxrpc: Simplify ACK handling

2023-01-31T16:38:35+00:00

Now that general ACK transmission is done from the same thread as incoming DATA packet wrangling, there's no possibility that the SACK table will be being updated by the latter whilst the former is trying to copy it to an ACK. This means that we can safely rotate the SACK table whilst updating it without having to take a lock, rather than keeping all the bits inside it in fixed place and copying and then rotating it in the transmitter. Therefore, simplify SACK handing by keeping track of starting point in the ring and rotate slots down as we consume them. Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org

rxrpc: De-atomic call->ackr_window and call->ackr_nr_unacked

2023-01-31T16:38:26+00:00

call->ackr_window doesn't need to be atomic as ACK generation and ACK transmission are now done in the same thread, so drop the atomic64 handling and split it into two separate members. Similarly, call->ackr_nr_unacked doesn't need to be atomic now either. Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org