[PATCH] nvmet-tcp: fix a segmentation fault during io parsing error

[elad.grupi at dell.com]

From: Elad Grupi <elad.grupi at dell.com>

In case there is an io that contains inline data and it goes to
parsing error flow, command response will free command and iov
before clearing the data on the socket buffer.
This will delay the command response until receive flow is completed.

Signed-off-by: Elad Grupi <elad.grupi at dell.com>
---
 drivers/nvme/target/tcp.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index d658c6e8263a..2b5d0c9c4e38 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -702,6 +702,17 @@ static int nvmet_tcp_try_send_one(struct nvmet_tcp_queue *queue,
 			return 0;
 	}
 
+	if (unlikely((cmd->flags & NVMET_TCP_F_INIT_FAILED) &&
+			nvmet_tcp_has_data_in(cmd) &&
+			nvmet_tcp_has_inline_data(cmd))) {
+		/*
+		 * wait for inline data before processing the response
+		 * so the iov will not be freed
+		 */
+		queue->snd_cmd = NULL;
+		goto done_send;
+	}
+
 	if (cmd->state == NVMET_TCP_SEND_DATA_PDU) {
 		ret = nvmet_try_send_data_pdu(cmd);
 		if (ret <= 0)
@@ -1107,7 +1118,9 @@ static int nvmet_tcp_try_recv_data(struct nvmet_tcp_queue *queue)
 	if (!(cmd->flags & NVMET_TCP_F_INIT_FAILED) &&
 	    cmd->rbytes_done == cmd->req.transfer_len) {
 		cmd->req.execute(&cmd->req);
-	}
+	} else if ((cmd->flags & NVMET_TCP_F_INIT_FAILED) &&
+			cmd->rbytes_done == cmd->req.transfer_len)
+		nvmet_tcp_queue_response(&cmd->req);
 
 	nvmet_prepare_receive_pdu(queue);
 	return 0;
@@ -1147,6 +1160,8 @@ static int nvmet_tcp_try_recv_ddgst(struct nvmet_tcp_queue *queue)
 	if (!(cmd->flags & NVMET_TCP_F_INIT_FAILED) &&
 	    cmd->rbytes_done == cmd->req.transfer_len)
 		cmd->req.execute(&cmd->req);
+	else if ((cmd->flags & NVMET_TCP_F_INIT_FAILED))
+		nvmet_tcp_queue_response(&cmd->req);
 	ret = 0;
 out:
 	nvmet_prepare_receive_pdu(queue);
-- 
2.18.2