From: David Howells dhowells@redhat.com
[ Upstream commit 02c28dffb13abbaaedece1e4a6493b48ad3f913a ]
Commit 2ad6691d988c, which moved the modification of the status annotation for a packet in the Tx buffer prior to the retransmission moved the state clearance, but managed to lose the bit that set it to UNACK.
Consequently, if a retransmission occurs, the packet is accidentally changed to the ACK state (ie. 0) by masking it off, which means that the packet isn't counted towards the tally of newly-ACK'd packets if it gets hard-ACK'd. This then prevents the congestion control algorithm from recovering properly.
Fix by reinstating the change of state to UNACK.
Spotted by the generic/460 xfstest.
Fixes: 2ad6691d988c ("rxrpc: Fix race between incoming ACK parser and retransmitter") Signed-off-by: David Howells dhowells@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/rxrpc/call_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c index 985fb89202d0c..9ff85ee8337cd 100644 --- a/net/rxrpc/call_event.c +++ b/net/rxrpc/call_event.c @@ -253,7 +253,7 @@ static void rxrpc_resend(struct rxrpc_call *call, unsigned long now_j) * confuse things */ annotation &= ~RXRPC_TX_ANNO_MASK; - annotation |= RXRPC_TX_ANNO_RESENT; + annotation |= RXRPC_TX_ANNO_UNACK | RXRPC_TX_ANNO_RESENT; call->rxtx_annotations[ix] = annotation;
skb = call->rxtx_buffer[ix];