Re: [PATCH net-next 07/15] rxrpc: Fix accidental cancellation of scheduled resend by ACK parser

From: Sergei Shtylyov
Date: Fri Sep 23 2016 - 14:02:53 EST


Hello.

On 09/23/2016 06:16 PM, David Howells wrote:

When rxrpc_input_soft_acks() is parsing the soft-ACKs from an ACK packet,
it updates the Tx packet annotations in the annotation buffer. If a
soft-ACK is an ACK, then we overwrite unack'd, nak'd or to-be-retransmitted
states and that is fine; but if the soft-ACK is an NACK, we overwrite the
to-be-retransmitted with a nak - which isn't.

Instead, we need to let any scheduled retransmission stand if the packet
was NAK'd.

Note that we don't reissue a resend if the annotation is in the
to-be-retransmitted state because someone else must've scheduled the
resend already.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

net/rxrpc/input.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 06027b6d9c19..d3d69ab1f0a1 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -479,6 +479,8 @@ static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks,
case RXRPC_ACK_TYPE_NACK:
if (anno_type == RXRPC_TX_ANNO_NAK)
continue;
+ if (anno_type == RXRPC_TX_ANNO_RETRANS)
+ continue;

Why not fold the above 2 *if*s together? Or use *else if* at least?

MBR, Sergei