From 6b355b33a64fd6d8ead2b838ec16fb9b551f71e8 Mon Sep 17 00:00:00 2001
From: David Fries <David@Fries.net>
Date: Wed, 15 Jan 2014 22:29:12 -0600
Subject: w1: fix w1_send_slave dropping a slave id

Previous logic,
if (avail > 8) {
	store slave;
	return;
}
send data; clear;

The logic error is, if there isn't space send the buffer and clear,
but the slave wasn't added to the now empty buffer loosing that slave
id.  It also should have been "if (avail >= 8)" because when it is 8,
there is space.

Instead, if there isn't space send and clear the buffer, then there is
always space for the slave id.

Signed-off-by: David Fries <David@Fries.net>
Cc: stable@vger.kernel.org
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/w1/w1_netlink.c b/drivers/w1/w1_netlink.c
index 40788c9..73705af 100644
--- a/drivers/w1/w1_netlink.c
+++ b/drivers/w1/w1_netlink.c
@@ -54,28 +54,29 @@ static void w1_send_slave(struct w1_master *dev, u64 rn)
 	struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
 	struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
 	int avail;
+	u64 *data;
 
 	/* update kernel slave list */
 	w1_slave_found(dev, rn);
 
 	avail = dev->priv_size - cmd->len;
 
-	if (avail > 8) {
-		u64 *data = (void *)(cmd + 1) + cmd->len;
+	if (avail < 8) {
+		msg->ack++;
+		cn_netlink_send(msg, 0, GFP_KERNEL);
 
-		*data = rn;
-		cmd->len += 8;
-		hdr->len += 8;
-		msg->len += 8;
-		return;
+		msg->len = sizeof(struct w1_netlink_msg) +
+			sizeof(struct w1_netlink_cmd);
+		hdr->len = sizeof(struct w1_netlink_cmd);
+		cmd->len = 0;
 	}
 
-	msg->ack++;
-	cn_netlink_send(msg, 0, GFP_KERNEL);
+	data = (void *)(cmd + 1) + cmd->len;
 
-	msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
-	hdr->len = sizeof(struct w1_netlink_cmd);
-	cmd->len = 0;
+	*data = rn;
+	cmd->len += 8;
+	hdr->len += 8;
+	msg->len += 8;
 }
 
 static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg,
-- 
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