iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

9p/trans_virtio: discard zero-length reply

Browse Source 
commit 26d99834f89e76514076d9cd06f61e56e6a509b8 upstream.

When a 9p request is successfully flushed, the server is expected to just
mark it as used without sending a 9p reply (ie, without writing data into
the buffer). In this case, virtqueue_get_buf() will return len == 0 and
we must not report a REQ_STATUS_RCVD status to the client, otherwise the
client will erroneously assume the request has not been flushed.

Cc: stable@vger.kernel.org
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Greg Kurz 2018-01-22 22:02:05 +01:00 committed by Greg Kroah-Hartman
parent 61c07810bf
commit 8a8c9588c2
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
net/9p/trans_virtio.c
View File

@ -160,7 +160,8 @@ static void req_done(struct virtqueue *vq)
spin_unlock_irqrestore(&chan->lock, flags);
/* Wakeup if anyone waiting for VirtIO ring space. */
wake_up(chan->vc_wq);
p9_client_cb(chan->client, req, REQ_STATUS_RCVD);
if (len)
p9_client_cb(chan->client, req, REQ_STATUS_RCVD);
}
}