4.9-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 298bc15b2079c324e82d0a6fda39c3d762af7282 ]
Move the out-of-order and duplicate ACK packet check to before the call to rxrpc_input_ackinfo() so that the receive window size and MTU size are only checked in the latest ACK packet and don't regress.
Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells dhowells@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/rxrpc/input.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-)
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c index 7bfde4737cb3..a4380e182e6c 100644 --- a/net/rxrpc/input.c +++ b/net/rxrpc/input.c @@ -808,6 +808,16 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb, rxrpc_propose_ack_respond_to_ack); }
+ /* Discard any out-of-order or duplicate ACKs. */ + if (before_eq(sp->hdr.serial, call->acks_latest)) { + _debug("discard ACK %d <= %d", + sp->hdr.serial, call->acks_latest); + return; + } + call->acks_latest_ts = skb->tstamp; + call->acks_latest = sp->hdr.serial; + + /* Parse rwind and mtu sizes if provided. */ ioffset = offset + nr_acks + 3; if (skb->len >= ioffset + sizeof(buf.info)) { if (skb_copy_bits(skb, ioffset, &buf.info, sizeof(buf.info)) < 0) @@ -829,15 +839,6 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb, return; }
- /* Discard any out-of-order or duplicate ACKs. */ - if (before_eq(sp->hdr.serial, call->acks_latest)) { - _debug("discard ACK %d <= %d", - sp->hdr.serial, call->acks_latest); - return; - } - call->acks_latest_ts = skb->tstamp; - call->acks_latest = sp->hdr.serial; - if (before(hard_ack, call->tx_hard_ack) || after(hard_ack, call->tx_top)) return rxrpc_proto_abort("AKW", call, 0);