From 0b20406cda621c2495d10baab1e87127ceb43337 Mon Sep 17 00:00:00 2001
From: Sven Eckelmann <sven.eckelmann@gmx.de>
Date: Mon, 27 Sep 2010 15:54:44 -0700
Subject: [PATCH] net/9p: Mount only matching virtio channels

p9_virtio_create will only compare the the channel's tag characters
against the device name till the end of the channel's tag but not till
the end of the device name. This means that if a user defines channels
with the tags foo and foobar then he would mount foo when he requested
foonot and may mount foo when he requested foobar.

Thus it is necessary to check both string lengths against each other in
case of a successful partial string match.

Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/9p/trans_virtio.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index dcfbe99ff81c..b88515936e4b 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -329,7 +329,8 @@ p9_virtio_create(struct p9_client *client, const char *devname, char *args)
 
 	mutex_lock(&virtio_9p_lock);
 	list_for_each_entry(chan, &virtio_chan_list, chan_list) {
-		if (!strncmp(devname, chan->tag, chan->tag_len)) {
+		if (!strncmp(devname, chan->tag, chan->tag_len) &&
+		    strlen(devname) == chan->tag_len) {
 			if (!chan->inuse) {
 				chan->inuse = true;
 				found = 1;
-- 
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