[PATCH 4.16 096/272] rxrpc: Dont treat call aborts as conn aborts

Greg Kroah-Hartman
2018-05-28T11:56:39Z

From: David Howells <dhowells@redhat.com>

[ Upstream commit 57b0c9d49b94bbeb53649b7fbd264603c1ebd585 ]

If a call-level abort is received for the previous call to complete on a
connection channel, then that abort is queued for the connection processor
to handle. Unfortunately, the connection processor then assumes without
checking that the abort is connection-level (ie. callNumber is 0) and
distributes it over all active calls on that connection, thereby
incorrectly aborting them.

Fix this by discarding aborts aimed at a completed call.

Further, discard all packets aimed at a call that's complete if there's
currently an active call on a channel, since the DATA packets associated
with the new call automatically terminate the old call.

Fixes: 18bfeba50dfd ("rxrpc: Perform terminal call ACK/ABORT retransmission from conn processor")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/rxrpc/input.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)

--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -1240,16 +1240,19 @@ void rxrpc_data_ready(struct sock *udp_s
goto discard_unlock;

if (sp->hdr.callNumber == chan->last_call) {
- /* For the previous service call, if completed successfully, we
- * discard all further packets.
+ if (chan->call ||
+ sp->hdr.type == RXRPC_PACKET_TYPE_ABORT)
+ goto discard_unlock;
+
+ /* For the previous service call, if completed
+ * successfully, we discard all further packets.
*/
if (rxrpc_conn_is_service(conn) &&
- (chan->last_type == RXRPC_PACKET_TYPE_ACK ||
- sp->hdr.type == RXRPC_PACKET_TYPE_ABORT))
+ chan->last_type == RXRPC_PACKET_TYPE_ACK)
goto discard_unlock;

- /* But otherwise we need to retransmit the final packet from
- * data cached in the connection record.
+ /* But otherwise we need to retransmit the final packet
+ * from data cached in the connection record.
*/
rxrpc_post_packet_to_conn(conn, skb);
goto out_unlock;