[PATCH] nvme: catch errors from nvme_configure_metadata()

[Hannes Reinecke]

nvme_configure_metadata() is issuing I/O, so we might incur an I/O
error which will cause the connection to be reset.
But in that case any further probing will race with reset and
cause UAF errors.
So return a status from nvme_configure_metadata() and abort
probing if there was an I/O error.

Signed-off-by: Hannes Reinecke <hare at suse.de>
---
 drivers/nvme/host/core.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 88b54cdcbd68..fd28e6b6574c 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1814,16 +1814,18 @@ static int nvme_init_ms(struct nvme_ns *ns, struct nvme_id_ns *id)
 	return ret;
 }
 
-static void nvme_configure_metadata(struct nvme_ns *ns, struct nvme_id_ns *id)
+static int nvme_configure_metadata(struct nvme_ns *ns, struct nvme_id_ns *id)
 {
 	struct nvme_ctrl *ctrl = ns->ctrl;
+	int ret;
 
-	if (nvme_init_ms(ns, id))
-		return;
+	ret = nvme_init_ms(ns, id);
+	if (ret)
+		return ret;
 
 	ns->features &= ~(NVME_NS_METADATA_SUPPORTED | NVME_NS_EXT_LBAS);
 	if (!ns->ms || !(ctrl->ops->flags & NVME_F_METADATA_SUPPORTED))
-		return;
+		return 0;
 
 	if (ctrl->ops->flags & NVME_F_FABRICS) {
 		/*
@@ -1832,7 +1834,7 @@ static void nvme_configure_metadata(struct nvme_ns *ns, struct nvme_id_ns *id)
 		 * remap the separate metadata buffer from the block layer.
 		 */
 		if (WARN_ON_ONCE(!(id->flbas & NVME_NS_FLBAS_META_EXT)))
-			return;
+			return 0;
 
 		ns->features |= NVME_NS_EXT_LBAS;
 
@@ -1859,6 +1861,7 @@ static void nvme_configure_metadata(struct nvme_ns *ns, struct nvme_id_ns *id)
 		else
 			ns->features |= NVME_NS_METADATA_SUPPORTED;
 	}
+	return 0;
 }
 
 static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
@@ -2032,7 +2035,11 @@ static int nvme_update_ns_info_block(struct nvme_ns *ns,
 	ns->lba_shift = id->lbaf[lbaf].ds;
 	nvme_set_queue_limits(ns->ctrl, ns->queue);
 
-	nvme_configure_metadata(ns, id);
+	ret = nvme_configure_metadata(ns, id);
+	if (ret < 0) {
+		blk_mq_unfreeze_queue(ns->disk->queue);
+		goto out;
+	}
 	nvme_set_chunk_sectors(ns, id);
 	nvme_update_disk_info(ns->disk, ns, id);
 
-- 
2.35.3