nvme: don't blindly overwrite identifiers on disk revalidate

Instead validate that these identifiers do not change, as that is
prohibited by the specification.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index b87cf3a..b0dd58d 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1236,6 +1236,8 @@ static int nvme_revalidate_disk(struct gendisk *disk)
        struct nvme_ns *ns = disk->private_data;
        struct nvme_ctrl *ctrl = ns->ctrl;
        struct nvme_id_ns *id;
+       u8 eui64[8] = { 0 }, nguid[16] = { 0 };
+       uuid_t uuid = uuid_null;
        int ret = 0;
 
        if (test_bit(NVME_NS_DEAD, &ns->flags)) {
@@ -1252,7 +1254,15 @@ static int nvme_revalidate_disk(struct gendisk *disk)
                goto out;
        }
 
-       nvme_report_ns_ids(ctrl, ns->ns_id, id, ns->eui, ns->nguid, &ns->uuid);
+       nvme_report_ns_ids(ctrl, ns->ns_id, id, eui64, nguid, &uuid);
+       if (!uuid_equal(&ns->uuid, &uuid) ||
+           memcmp(&ns->nguid, &nguid, sizeof(ns->nguid)) ||
+           memcmp(&ns->eui, &eui64, sizeof(ns->eui))) {
+               dev_err(ctrl->device,
+                       "identifiers changed for nsid %d\n", ns->ns_id);
+               ret = -ENODEV;
+       }
+
 out:
        kfree(id);
        return ret;