diff options
| author | Greg Kurz <groug@kaod.org> | 2018-01-22 22:02:05 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-22 15:43:50 +0100 |
| commit | 39e0a6bd07182815062c74fc73ce0ea94578ce00 (patch) | |
| tree | 307227b52cd225f46dd992ccb2b4d10f169fd1c1 | |
| parent | efb1cbc229f122bc1d1b5e85bdd2da971c953f2e (diff) | |
9p/trans_virtio: discard zero-length reply
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>
| -rw-r--r-- | net/9p/trans_virtio.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index f3a4efcf1456..3aa5a93ad107 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -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); } } |