From: Lars Ellenberg Date: Thu, 20 Dec 2018 16:23:32 +0000 (+0100) Subject: drbd: disconnect, if the wrong UUIDs are attached on a connected peer X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=b17b59602b6dcf8f97a7dc7bc489a48388d7063a;p=linux.git drbd: disconnect, if the wrong UUIDs are attached on a connected peer With "on-no-data-accessible suspend-io", DRBD requires the next attach or connect to be to the very same data generation uuid tag it lost last. If we first lost connection to the peer, then later lost connection to our own disk, we would usually refuse to re-connect to the peer, because it presents the wrong data set. However, if the peer first connects without a disk, and then attached its disk, we accepted that same wrong data set, which would be "unexpected" by any user of that DRBD and cause "undefined results" (read: very likely data corruption). The fix is to forcefully disconnect as soon as we notice that the peer attached to the "wrong" dataset. Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index fbf30fe458624..0a9f3c65f70ad 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -4170,7 +4170,7 @@ static int receive_uuids(struct drbd_connection *connection, struct packet_info kfree(device->p_uuid); device->p_uuid = p_uuid; - if (device->state.conn < C_CONNECTED && + if ((device->state.conn < C_CONNECTED || device->state.pdsk == D_DISKLESS) && device->state.disk < D_INCONSISTENT && device->state.role == R_PRIMARY && (device->ed_uuid & ~((u64)1)) != (p_uuid[UI_CURRENT] & ~((u64)1))) {