Merge tag 'rxrpc-fixes-20160809' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Miscellaneous fixes

Here are a bunch of miscellaneous fixes to AF_RXRPC:

 (*) Fix an uninitialised pointer.

 (*) Fix error handling when we fail to connect a call.

 (*) Fix a NULL pointer dereference.

 (*) Fix two occasions where a packet is accessed again after being queued
     for someone else to deal with.

 (*) Fix a missing skb free.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 23 insertions, 11 deletions

diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index f5e9916..e60cf65 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -837,6 +837,9 @@ void rxrpc_process_call(struct work_struct *work)
 		return;
 	}
 
+	if (!call->conn)
+		goto skip_msg_init;
+
 	/* there's a good chance we're going to have to send a message, so set
 	 * one up in advance */
 	msg.msg_name	= &call->conn->params.peer->srx.transport;
@@ -859,6 +862,7 @@ void rxrpc_process_call(struct work_struct *work)
 	memset(iov, 0, sizeof(iov));
 	iov[0].iov_base	= &whdr;
 	iov[0].iov_len	= sizeof(whdr);
+skip_msg_init:
 
 	/* deal with events of a final nature */
 	if (test_bit(RXRPC_CALL_EV_RCVD_ERROR, &call->events)) {
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index c47f14f..ae057e0 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -275,6 +275,7 @@ error:
 	list_del_init(&call->link);
 	write_unlock_bh(&rxrpc_call_lock);
 
+	set_bit(RXRPC_CALL_RELEASED, &call->flags);
 	call->state = RXRPC_CALL_DEAD;
 	rxrpc_put_call(call);
 	_leave(" = %d", ret);
@@ -287,6 +288,7 @@ error:
 	 */
 found_user_ID_now_present:
 	write_unlock(&rx->call_lock);
+	set_bit(RXRPC_CALL_RELEASED, &call->flags);
 	call->state = RXRPC_CALL_DEAD;
 	rxrpc_put_call(call);
 	_leave(" = -EEXIST [%p]", call);
@@ -493,6 +495,7 @@ void rxrpc_release_call(struct rxrpc_call *call)
 		       (skb = skb_dequeue(&call->rx_oos_queue))) {
 			spin_unlock_bh(&call->lock);
 
+			sp = rxrpc_skb(skb);
 			_debug("- zap %s %%%u #%u",
 			       rxrpc_pkts[sp->hdr.type],
 			       sp->hdr.serial, sp->hdr.seq);
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 9e0f58e..70bb778 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -124,11 +124,15 @@ static int rxrpc_fast_process_data(struct rxrpc_call *call,
 	struct rxrpc_skb_priv *sp;
 	bool terminal;
 	int ret, ackbit, ack;
+	u32 serial;
+	u8 flags;
 
 	_enter("{%u,%u},,{%u}", call->rx_data_post, call->rx_first_oos, seq);
 
 	sp = rxrpc_skb(skb);
 	ASSERTCMP(sp->call, ==, NULL);
+	flags = sp->hdr.flags;
+	serial = sp->hdr.serial;
 
 	spin_lock(&call->lock);
 
@@ -192,8 +196,8 @@ static int rxrpc_fast_process_data(struct rxrpc_call *call,
 	sp->call = call;
 	rxrpc_get_call(call);
 	atomic_inc(&call->skb_count);
-	terminal = ((sp->hdr.flags & RXRPC_LAST_PACKET) &&
-		    !(sp->hdr.flags & RXRPC_CLIENT_INITIATED));
+	terminal = ((flags & RXRPC_LAST_PACKET) &&
+		    !(flags & RXRPC_CLIENT_INITIATED));
 	ret = rxrpc_queue_rcv_skb(call, skb, false, terminal);
 	if (ret < 0) {
 		if (ret == -ENOMEM || ret == -ENOBUFS) {
@@ -205,12 +209,13 @@ static int rxrpc_fast_process_data(struct rxrpc_call *call,
 	}
 
 	skb = NULL;
+	sp = NULL;
 
 	_debug("post #%u", seq);
 	ASSERTCMP(call->rx_data_post, ==, seq);
 	call->rx_data_post++;
 
-	if (sp->hdr.flags & RXRPC_LAST_PACKET)
+	if (flags & RXRPC_LAST_PACKET)
 		set_bit(RXRPC_CALL_RCVD_LAST, &call->flags);
 
 	/* if we've reached an out of sequence packet then we need to drain
@@ -226,7 +231,7 @@ static int rxrpc_fast_process_data(struct rxrpc_call *call,
 
 	spin_unlock(&call->lock);
 	atomic_inc(&call->ackr_not_idle);
-	rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, sp->hdr.serial, false);
+	rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial, false);
 	_leave(" = 0 [posted]");
 	return 0;
 
@@ -239,7 +244,7 @@ out:
 
 discard_and_ack:
 	_debug("discard and ACK packet %p", skb);
-	__rxrpc_propose_ACK(call, ack, sp->hdr.serial, true);
+	__rxrpc_propose_ACK(call, ack, serial, true);
 discard:
 	spin_unlock(&call->lock);
 	rxrpc_free_skb(skb);
@@ -247,7 +252,7 @@ discard:
 	return 0;
 
 enqueue_and_ack:
-	__rxrpc_propose_ACK(call, ack, sp->hdr.serial, true);
+	__rxrpc_propose_ACK(call, ack, serial, true);
 enqueue_packet:
 	_net("defer skb %p", skb);
 	spin_unlock(&call->lock);
@@ -567,13 +572,13 @@ done:
  * post connection-level events to the connection
  * - this includes challenges, responses and some aborts
  */
-static bool rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
+static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
 				      struct sk_buff *skb)
 {
 	_enter("%p,%p", conn, skb);
 
 	skb_queue_tail(&conn->rx_queue, skb);
-	return rxrpc_queue_conn(conn);
+	rxrpc_queue_conn(conn);
 }
 
 /*
@@ -694,7 +699,6 @@ void rxrpc_data_ready(struct sock *sk)
 
 	rcu_read_lock();
 
-retry_find_conn:
 	conn = rxrpc_find_connection_rcu(local, skb);
 	if (!conn)
 		goto cant_route_call;
@@ -702,8 +706,7 @@ retry_find_conn:
 	if (sp->hdr.callNumber == 0) {
 		/* Connection-level packet */
 		_debug("CONN %p {%d}", conn, conn->debug_id);
-		if (!rxrpc_post_packet_to_conn(conn, skb))
-			goto retry_find_conn;
+		rxrpc_post_packet_to_conn(conn, skb);
 	} else {
 		/* Call-bound packets are routed by connection channel. */
 		unsigned int channel = sp->hdr.cid & RXRPC_CHANNELMASK;
@@ -741,6 +744,8 @@ cant_route_call:
 	if (sp->hdr.type != RXRPC_PACKET_TYPE_ABORT) {
 		_debug("reject type %d",sp->hdr.type);
 		rxrpc_reject_packet(local, skb);
+	} else {
+		rxrpc_free_skb(skb);
 	}
 	_leave(" [no call]");
 	return;