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

commit b85f7d92d7bd7e3298159e8b1eed8cb8cbbb0348 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/9p/client.c b/net/9p/client.c
index 9e3b0e640da179a122f6f846bd8cff31920db159..ffaf0df6e3044a916a8192e69e0eba7654fb9478 100644 (file)
--- 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;