From: G. Liakhovetski <gl@dsa-ac.de>
Date: Sat, 9 Jun 2007 02:15:17 +0000 (-0700)
Subject: [IrDA]: Fix Rx/Tx path race.
X-Git-Tag: v2.6.22-rc5~39^2~9
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c0cfe7faa12f189ef1024fce5a710791d0062355;p=linux-2.6

[IrDA]: Fix Rx/Tx path race.

From: G. Liakhovetski <gl@dsa-ac.de>

We need to switch to NRM _before_ sending the final packet otherwise
we might hit a race condition where we get the first packet from the
peer while we're still in LAP_XMIT_P.

Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/include/net/irda/irlap.h b/include/net/irda/irlap.h
index f0248fb8e1..a3d370efb9 100644
--- a/include/net/irda/irlap.h
+++ b/include/net/irda/irlap.h
@@ -289,4 +289,21 @@ static inline void irlap_clear_disconnect(struct irlap_cb *self)
 	self->disconnect_pending = FALSE;
 }
 
+/*
+ * Function irlap_next_state (self, state)
+ *
+ *    Switches state and provides debug information
+ *
+ */
+static inline void irlap_next_state(struct irlap_cb *self, IRLAP_STATE state)
+{
+	/*
+	if (!self || self->magic != LAP_MAGIC)
+		return;
+
+	IRDA_DEBUG(4, "next LAP state = %s\n", irlap_state[state]);
+	*/
+	self->state = state;
+}
+
 #endif
diff --git a/net/irda/irlap_event.c b/net/irda/irlap_event.c
index 0b02073ffd..71c8055069 100644
--- a/net/irda/irlap_event.c
+++ b/net/irda/irlap_event.c
@@ -316,23 +316,6 @@ void irlap_do_event(struct irlap_cb *self, IRLAP_EVENT event,
 	}
 }
 
-/*
- * Function irlap_next_state (self, state)
- *
- *    Switches state and provides debug information
- *
- */
-static inline void irlap_next_state(struct irlap_cb *self, IRLAP_STATE state)
-{
-	/*
-	if (!self || self->magic != LAP_MAGIC)
-		return;
-
-	IRDA_DEBUG(4, "next LAP state = %s\n", irlap_state[state]);
-	*/
-	self->state = state;
-}
-
 /*
  * Function irlap_state_ndm (event, skb, frame)
  *
@@ -1086,7 +1069,6 @@ static int irlap_state_xmit_p(struct irlap_cb *self, IRLAP_EVENT event,
 			} else {
 				/* Final packet of window */
 				irlap_send_data_primary_poll(self, skb);
-				irlap_next_state(self, LAP_NRM_P);
 
 				/*
 				 * Make sure state machine does not try to send
diff --git a/net/irda/irlap_frame.c b/net/irda/irlap_frame.c
index 3c5a68e364..3013c49ab9 100644
--- a/net/irda/irlap_frame.c
+++ b/net/irda/irlap_frame.c
@@ -798,16 +798,19 @@ void irlap_send_data_primary_poll(struct irlap_cb *self, struct sk_buff *skb)
 		self->vs = (self->vs + 1) % 8;
 		self->ack_required = FALSE;
 
+		irlap_next_state(self, LAP_NRM_P);
 		irlap_send_i_frame(self, tx_skb, CMD_FRAME);
 	} else {
 		IRDA_DEBUG(4, "%s(), sending unreliable frame\n", __FUNCTION__);
 
 		if (self->ack_required) {
 			irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
+			irlap_next_state(self, LAP_NRM_P);
 			irlap_send_rr_frame(self, CMD_FRAME);
 			self->ack_required = FALSE;
 		} else {
 			skb->data[1] |= PF_BIT;
+			irlap_next_state(self, LAP_NRM_P);
 			irlap_send_ui_frame(self, skb_get(skb), self->caddr, CMD_FRAME);
 		}
 	}