drbd: bail out if a config requrest is over-determined, and not matching

We have resources resp. connections, volumes, and minor numbers.
A config request may specifies all three of them.
If it turns out that the minor belongs to a different connection, or a
different volume number in the same connection, that configuration
request is invalid.

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 0d3753be371c556218d19ccf9d99b5528cbee009..f965dfe4b5ff48d008fd2a88fa13c660e4c67e18 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -204,20 +204,20 @@ static int drbd_adm_prepare(struct sk_buff *skb, struct genl_info *info,
        }
 
        /* some more paranoia, if the request was over-determined */
+       if (adm_ctx.mdev && adm_ctx.tconn &&
+           adm_ctx.mdev->tconn != adm_ctx.tconn) {
+               pr_warning("request: minor=%u, conn=%s; but that minor belongs to connection %s\n",
+                               adm_ctx.minor, adm_ctx.conn_name, adm_ctx.mdev->tconn->name);
+               drbd_msg_put_info("minor exists in different connection");
+               return ERR_INVALID_REQUEST;
+       }
        if (adm_ctx.mdev &&
            adm_ctx.volume != VOLUME_UNSPECIFIED &&
            adm_ctx.volume != adm_ctx.mdev->vnr) {
                pr_warning("request: minor=%u, volume=%u; but that minor is volume %u in %s\n",
                                adm_ctx.minor, adm_ctx.volume,
                                adm_ctx.mdev->vnr, adm_ctx.mdev->tconn->name);
-               drbd_msg_put_info("over-determined configuration context mismatch");
-               return ERR_INVALID_REQUEST;
-       }
-       if (adm_ctx.mdev && adm_ctx.tconn &&
-           adm_ctx.mdev->tconn != adm_ctx.tconn) {
-               pr_warning("request: minor=%u, conn=%s; but that minor belongs to connection %s\n",
-                               adm_ctx.minor, adm_ctx.conn_name, adm_ctx.mdev->tconn->name);
-               drbd_msg_put_info("over-determined configuration context mismatch");
+               drbd_msg_put_info("minor exists as different volume");
                return ERR_INVALID_REQUEST;
        }
        if (adm_ctx.mdev && !adm_ctx.tconn)