Commit 7c2fd760 authored by Puranjay Mohan's avatar Puranjay Mohan Committed by Keith Busch
Browse files

nvme: fix metadata handling in nvme-passthrough 

On an NVMe namespace that does not support metadata, it is possible to
send an IO command with metadata through io-passthru. This allows issues
like [1] to trigger in the completion code path.
nvme_map_user_request() doesn't check if the namespace supports metadata
before sending it forward. It also allows admin commands with metadata to
be processed as it ignores metadata when bdev == NULL and may report
success.

Reject an IO command with metadata when the NVMe namespace doesn't
support it and reject an admin command if it has metadata.

[1] https://lore.kernel.org/all/mb61pcylvnym8.fsf@amazon.com/



Suggested-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarPuranjay Mohan <pjy@amazon.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarSagi Grimberg <sagi@grimberg.me>
Reviewed-by: default avatarAnuj Gupta <anuj20.g@samsung.com>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
parent cead0b89

drivers/nvme/host/ioctl.c

+14 −8
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
 * Copyright (c) 2017-2021 Christoph Hellwig.

 */

#include <linux/bio-integrity.h>

#include <linux/blk-integrity.h>

#include <linux/ptrace.h>	/* for force_successful_syscall_return */

#include <linux/nvme_ioctl.h>

#include <linux/io_uring/cmd.h>
@@ -119,9 +120,14 @@ static int nvme_map_user_request(struct request *req, u64 ubuffer, 
	struct request_queue *q = req->q;

	struct nvme_ns *ns = q->queuedata;

	struct block_device *bdev = ns ? ns->disk->part0 : NULL;

	bool supports_metadata = bdev && blk_get_integrity(bdev->bd_disk);

	bool has_metadata = meta_buffer && meta_len;

	struct bio *bio = NULL;

	int ret;



	if (has_metadata && !supports_metadata)

		return -EINVAL;



	if (ioucmd && (ioucmd->flags & IORING_URING_CMD_FIXED)) {

		struct iov_iter iter;
@@ -143,16 +149,16 @@ static int nvme_map_user_request(struct request *req, u64 ubuffer, 
		goto out;



	bio = req->bio;

	if (bdev) {

	if (bdev)

		bio_set_dev(bio, bdev);

		if (meta_buffer && meta_len) {



	if (has_metadata) {

		ret = bio_integrity_map_user(bio, meta_buffer, meta_len,

					     meta_seed);

		if (ret)

			goto out_unmap;

		req->cmd_flags |= REQ_INTEGRITY;

	}

	}



	return ret;