On 2021/09/22 17:22, Ming Lei wrote:
On Sun, Sep 19, 2021 at 06:34:28PM +0800, yukuai (C) wrote:
On 2021/09/16 17:33, Yu Kuai wrote:
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 614c6ab2b8fe..c724a5bd7fa4 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -746,6 +746,10 @@ 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));
Hi, Ming
Any suggestions about this patch?
I think this one relies on nbd protocol between server and client, and
does the protocol require both request and reply xmitted via same
socket?
I searched nbd-server source code, and found that socket_read() and
send_reply->socket_write() are always come in pares and using the same
socket.
BTW, if server reply a read request from a unexpected sock, then
nbd_read_stat() might stuck in receiving the read data. And for worse,
nbd_read_stat() can mistake the normal reply message for the read data
afterwards and corrupt client.
Thanks,
Kuai
