net/9p: fix client code to fail more gracefully on protocol error

There was a BUG_ON to protect against a bad id which could be dealt with
more gracefully.

Reported-by: Natalie Orlin <norlin@us.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/9p/client.c b/net/9p/client.c
index 9e3b0e640da1..81e667b6bbbd 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -280,7 +280,8 @@ struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
          * buffer to read the data into */
         tag++;
 
-        BUG_ON(tag >= c->max_tag);
+        if(tag >= c->max_tag) 
+                return NULL;
 
         row = tag / P9_ROW_MAXTAG;
         col = tag % P9_ROW_MAXTAG;