[PATCH 4.7 55/69] libceph: fix return value check in alloc_msg_with_page_vector()

[Greg Kroah-Hartman]

4.7-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Wei Yongjun <weiyj.lk@xxxxxxxxx>

commit c22e853a2ed19321d00c1eae339ffdc4f5e7757e upstream.

In case of error, the function ceph_alloc_page_vector() returns
ERR_PTR() and never returns NULL. The NULL test in the return value
check should be replaced with IS_ERR().

Fixes: 1907920324f1 ('libceph: support for sending notifies')
Signed-off-by: Wei Yongjun <weiyj.lk@xxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/ceph/osd_client.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -4187,7 +4187,7 @@ static struct ceph_msg *alloc_msg_with_p
 
 		pages = ceph_alloc_page_vector(calc_pages_for(0, data_len),
 					       GFP_NOIO);
-		if (!pages) {
+		if (IS_ERR(pages)) {
 			ceph_msg_put(m);
 			return NULL;
 		}