[PATCH v4 5/6] nbd: check sock index in nbd_read_stat()

[Yu Kuai]

The sock that clent send request in nbd_send_cmd() and receive reply
in nbd_read_stat() should be the same.

Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
 drivers/block/nbd.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 6e22e80a5488..807c8cbccaae 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -747,6 +747,10 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index)
 		ret = -ENOENT;
 		goto out;
 	}
+	if (cmd->index != index) {
+		dev_err(disk_to_dev(nbd->disk), "Unexpected reply %d from different sock %d (expected %d)",
+			tag, index, cmd->index);
+	}
 	if (cmd->cmd_cookie != nbd_handle_to_cookie(handle)) {
 		dev_err(disk_to_dev(nbd->disk), "Double reply on req %p, cmd_cookie %u, handle cookie %u\n",
 			req, cmd->cmd_cookie, nbd_handle_to_cookie(handle));
-- 
2.31.1