From 14e3995e63759b80eb22a3c06958d105db4d3f79 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Tue, 16 May 2017 14:22:47 +0000 Subject: [PATCH] xen/9pfs: fix return value check in xen_9pfs_front_probe() In case of error, the function xenbus_read() returns ERR_PTR() and never returns NULL. The NULL test in the return value check should be replaced with IS_ERR(). Fixes: 71ebd71921e4 ("xen/9pfs: connect to the backend") Signed-off-by: Wei Yongjun Reviewed-by: Stefano Stabellini --- net/9p/trans_xen.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index 71e85643b3f9..83fe487f460e 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -454,8 +454,8 @@ static int xen_9pfs_front_probe(struct xenbus_device *dev, goto error_xenbus; } priv->tag = xenbus_read(xbt, dev->nodename, "tag", NULL); - if (!priv->tag) { - ret = -EINVAL; + if (IS_ERR(priv->tag)) { + ret = PTR_ERR(priv->tag); goto error_xenbus; } ret = xenbus_transaction_end(xbt, 0);