Commit ea8e356a authored by Maurizio Lombardi's avatar Maurizio Lombardi Committed by Keith Busch
Browse files

nvmet-tcp: propagate nvmet_tcp_build_pdu_iovec() errors to its callers 



Currently, when nvmet_tcp_build_pdu_iovec() detects an out-of-bounds
PDU length or offset, it triggers nvmet_tcp_fatal_error(cmd->queue)
and returns early. However, because the function returns void, the
callers are entirely unaware that a fatal error has occurred and
that the cmd->recv_msg.msg_iter was left uninitialized.

Callers such as nvmet_tcp_handle_h2c_data_pdu() proceed to blindly
overwrite the queue state with queue->rcv_state = NVMET_TCP_RECV_DATA
Consequently, the socket receiving loop may attempt to read incoming
network data into the uninitialized iterator.

Fix this by shifting the error handling responsibility to the callers.

Fixes: 52a0a985 ("nvmet-tcp: add bounds checks in nvmet_tcp_build_pdu_iovec")
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Reviewed-by: default avatarYunje Shin <ioerts@kookmin.ac.kr>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: default avatarMaurizio Lombardi <mlombard@redhat.com>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
parent 23528aa3

drivers/nvme/target/tcp.c

+29 −22
Original line number Diff line number Diff line
@@ -351,7 +351,7 @@ static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd) 


static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue);



static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd)

static int nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd)

{

	struct bio_vec *iov = cmd->iov;

	struct scatterlist *sg;
@@ -364,22 +364,19 @@ static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd) 
	offset = cmd->rbytes_done;

	cmd->sg_idx = offset / PAGE_SIZE;

	sg_offset = offset % PAGE_SIZE;

	if (!cmd->req.sg_cnt || cmd->sg_idx >= cmd->req.sg_cnt) {

		nvmet_tcp_fatal_error(cmd->queue);

		return;

	}

	if (!cmd->req.sg_cnt || cmd->sg_idx >= cmd->req.sg_cnt)

		return -EPROTO;



	sg = &cmd->req.sg[cmd->sg_idx];

	sg_remaining = cmd->req.sg_cnt - cmd->sg_idx;



	while (length) {

		if (!sg_remaining) {

			nvmet_tcp_fatal_error(cmd->queue);

			return;

		}

		if (!sg->length || sg->length <= sg_offset) {

			nvmet_tcp_fatal_error(cmd->queue);

			return;

		}

		if (!sg_remaining)

			return -EPROTO;



		if (!sg->length || sg->length <= sg_offset)

			return -EPROTO;



		u32 iov_len = min_t(u32, length, sg->length - sg_offset);



		bvec_set_page(iov, sg_page(sg), iov_len,
@@ -394,6 +391,7 @@ static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd) 


	iov_iter_bvec(&cmd->recv_msg.msg_iter, ITER_DEST, cmd->iov,

		      nr_pages, cmd->pdu_len);

	return 0;

}



static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue)
@@ -931,7 +929,7 @@ static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue) 
	return 0;

}



static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue,

static int nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue,

		struct nvmet_tcp_cmd *cmd, struct nvmet_req *req)

{

	size_t data_len = le32_to_cpu(req->cmd->common.dptr.sgl.length);
@@ -947,19 +945,23 @@ static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue, 
	if (!nvme_is_write(cmd->req.cmd) || !data_len ||

	    data_len > cmd->req.port->inline_data_size) {

		nvmet_prepare_receive_pdu(queue);

		return;

		return 0;

	}



	ret = nvmet_tcp_map_data(cmd);

	if (unlikely(ret)) {

		pr_err("queue %d: failed to map data\n", queue->idx);

		nvmet_tcp_fatal_error(queue);

		return;

		return -EPROTO;

	}



	queue->rcv_state = NVMET_TCP_RECV_DATA;

	nvmet_tcp_build_pdu_iovec(cmd);

	cmd->flags |= NVMET_TCP_F_INIT_FAILED;

	ret = nvmet_tcp_build_pdu_iovec(cmd);

	if (unlikely(ret))

		pr_err("queue %d: failed to build PDU iovec\n", queue->idx);



	return ret;

}



static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue)
@@ -1011,7 +1013,10 @@ static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue) 
		goto err_proto;

	}

	cmd->pdu_recv = 0;

	nvmet_tcp_build_pdu_iovec(cmd);

	if (unlikely(nvmet_tcp_build_pdu_iovec(cmd))) {

		pr_err("queue %d: failed to build PDU iovec\n", queue->idx);

		goto err_proto;

	}

	queue->cmd = cmd;

	queue->rcv_state = NVMET_TCP_RECV_DATA;
@@ -1074,8 +1079,7 @@ static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue) 
			le32_to_cpu(req->cmd->common.dptr.sgl.length),

			le16_to_cpu(req->cqe->status));



		nvmet_tcp_handle_req_failure(queue, queue->cmd, req);

		return 0;

		return nvmet_tcp_handle_req_failure(queue, queue->cmd, req);

	}



	ret = nvmet_tcp_map_data(queue->cmd);
@@ -1092,8 +1096,11 @@ static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue) 
	if (nvmet_tcp_need_data_in(queue->cmd)) {

		if (nvmet_tcp_has_inline_data(queue->cmd)) {

			queue->rcv_state = NVMET_TCP_RECV_DATA;

			nvmet_tcp_build_pdu_iovec(queue->cmd);

			return 0;

			ret = nvmet_tcp_build_pdu_iovec(queue->cmd);

			if (unlikely(ret))

				pr_err("queue %d: failed to build PDU iovec\n",

					queue->idx);

			return ret;

		}

		/* send back R2T */

		nvmet_tcp_queue_response(&queue->cmd->req);