From 81524b6312535897707f2942695da1d359a5e56b Mon Sep 17 00:00:00 2001 From: David Howells Date: Sat, 21 May 2022 09:03:24 +0100 Subject: [PATCH] rxrpc: Don't let ack.previousPacket regress The previousPacket field in the rx ACK packet should never go backwards - it's now the highest DATA sequence number received, not the last on received (it used to be used for out of sequence detection). Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller --- net/rxrpc/ar-internal.h | 4 ++-- net/rxrpc/input.c | 4 +++- net/rxrpc/output.c | 2 +- 3 files changed, 6 insertions(+), 4 deletions(-) diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index 9a9688c41d4d..8465985a4cb6 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -679,7 +679,7 @@ struct rxrpc_call { /* Receive-phase ACK management (ACKs we send). */ u8 ackr_reason; /* reason to ACK */ rxrpc_serial_t ackr_serial; /* serial of packet being ACK'd */ - rxrpc_seq_t ackr_prev_seq; /* previous sequence number received */ + rxrpc_seq_t ackr_highest_seq; /* Higest sequence number received */ rxrpc_seq_t ackr_consumed; /* Highest packet shown consumed */ rxrpc_seq_t ackr_seen; /* Highest packet shown seen */ @@ -694,7 +694,7 @@ struct rxrpc_call { /* Transmission-phase ACK management (ACKs we've received). */ ktime_t acks_latest_ts; /* Timestamp of latest ACK received */ rxrpc_seq_t acks_first_seq; /* first sequence number received */ - rxrpc_seq_t acks_prev_seq; /* previous sequence number received */ + rxrpc_seq_t acks_prev_seq; /* Highest previousPacket received */ rxrpc_seq_t acks_lowest_nak; /* Lowest NACK in the buffer (or ==tx_hard_ack) */ rxrpc_seq_t acks_lost_top; /* tx_top at the time lost-ack ping sent */ rxrpc_serial_t acks_lost_ping; /* Serial number of probe ACK */ diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c index f11673cda217..2e61545ad8ca 100644 --- a/net/rxrpc/input.c +++ b/net/rxrpc/input.c @@ -453,7 +453,6 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb) !rxrpc_receiving_reply(call)) goto unlock; - call->ackr_prev_seq = seq0; hard_ack = READ_ONCE(call->rx_hard_ack); nr_subpackets = sp->nr_subpackets; @@ -534,6 +533,9 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb) ack_serial = serial; } + if (after(seq0, call->ackr_highest_seq)) + call->ackr_highest_seq = seq0; + /* Queue the packet. We use a couple of memory barriers here as need * to make sure that rx_top is perceived to be set after the buffer * pointer and that the buffer pointer is set after the annotation and diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c index a45c83f22236..46aae9b7006f 100644 --- a/net/rxrpc/output.c +++ b/net/rxrpc/output.c @@ -89,7 +89,7 @@ static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn, pkt->ack.bufferSpace = htons(8); pkt->ack.maxSkew = htons(0); pkt->ack.firstPacket = htonl(hard_ack + 1); - pkt->ack.previousPacket = htonl(call->ackr_prev_seq); + pkt->ack.previousPacket = htonl(call->ackr_highest_seq); pkt->ack.serial = htonl(serial); pkt->ack.reason = reason; pkt->ack.nAcks = top - hard_ack; -- 2.11.0