drbd: use kzalloc and memset(,0,) to start with clean buffers in drbd_nl

Make sure we start with clean buffers to not accidentally send garbage
back to userspace. Note: has not been observed; but just in case.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index f969d8717e235d3ef8e918e3b4441e2c3494a8a0..80a389d24cdd4b1a0153f374f1d84411f3fad220 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -2211,7 +2211,7 @@ static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms
        reply_size += cm->reply_body_size;
 
        /* allocation not in the IO path, cqueue thread context */
-       cn_reply = kmalloc(reply_size, GFP_KERNEL);
+       cn_reply = kzalloc(reply_size, GFP_KERNEL);
        if (!cn_reply) {
                retcode = ERR_NOMEM;
                goto fail;
@@ -2382,7 +2382,7 @@ void drbd_bcast_ee(struct drbd_conf *mdev,
        /* receiver thread context, which is not in the writeout path (of this node),
         * but may be in the writeout path of the _other_ node.
         * GFP_NOIO to avoid potential "distributed deadlock". */
-       cn_reply = kmalloc(
+       cn_reply = kzalloc(
                sizeof(struct cn_msg)+
                sizeof(struct drbd_nl_cfg_reply)+
                sizeof(struct dump_ee_tag_len_struct)+
@@ -2517,6 +2517,7 @@ void drbd_nl_send_reply(struct cn_msg *req, int ret_code)
                (struct drbd_nl_cfg_reply *)cn_reply->data;
        int rr;
 
+       memset(buffer, 0, sizeof(buffer));
        cn_reply->id = req->id;
 
        cn_reply->seq = req->seq;