[PATCH] xen/9pfs: initialize len to 0 to detect xenbus_read errors

From: Stefano Stabellini
Date: Thu Apr 13 2017 - 13:58:12 EST


In order to use "len" to check for xenbus_read errors properly, we need
to initialize len to 0 before passing it to xenbus_read.

Signed-off-by: Stefano Stabellini <stefano@xxxxxxxxxxx>
CC: dan.carpenter@xxxxxxxxxx
CC: jgross@xxxxxxxx
CC: boris.ostrovsky@xxxxxxxxxx
CC: Eric Van Hensbergen <ericvh@xxxxxxxxx>
CC: Ron Minnich <rminnich@xxxxxxxxxx>
CC: Latchesar Ionkov <lucho@xxxxxxxxxx>
CC: v9fs-developer@xxxxxxxxxxxxxxxxxxxxx

---
Juergen, you could also merge this patch into commit
e9c53da56ff36458b1b8df95573f5dac80a1a956
---
---
net/9p/trans_xen.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c
index 4786424..71e8564 100644
--- a/net/9p/trans_xen.c
+++ b/net/9p/trans_xen.c
@@ -386,7 +386,7 @@ static int xen_9pfs_front_probe(struct xenbus_device *dev,
struct xenbus_transaction xbt;
struct xen_9pfs_front_priv *priv = NULL;
char *versions;
- unsigned int max_rings, max_ring_order, len;
+ unsigned int max_rings, max_ring_order, len = 0;

versions = xenbus_read(XBT_NIL, dev->otherend, "versions", &len);
if (!len)
--
1.9.1