Commit f63152958994 fixes a regression, however it fails to report an
error for malformed/short packets -- normally we should never see such
packets, but let's report an error for them just in case.
Fixes: f63152958994 ("hv_sock: Report EOF instead of -EIO for FIN")
Cc: [email protected]
Signed-off-by: Dexuan Cui <[email protected]>
---
Commit f63152958994 is currently only in net.git's master branch.
Changes since v1:
Integrated comments from Stefano Garzarella:
1) access 'vsk' directly:
s/hvs->vsk->peer_shutdown/vsk->peer_shutdown/
2) test the error condition first and return -EIO for that.
NO other changes.
net/vmw_vsock/hyperv_transport.c | 27 ++++++++++++++++++---------
1 file changed, 18 insertions(+), 9 deletions(-)
diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
index 76e78c83fdbc..f862988c1e86 100644
--- a/net/vmw_vsock/hyperv_transport.c
+++ b/net/vmw_vsock/hyperv_transport.c
@@ -704,17 +704,26 @@ static s64 hvs_stream_has_data(struct vsock_sock *vsk)
if (hvs->recv_desc) {
/* Here hvs->recv_data_len is 0, so hvs->recv_desc must
* be NULL unless it points to the 0-byte-payload FIN
- * packet: see hvs_update_recv_data().
+ * packet or a malformed/short packet: see
+ * hvs_update_recv_data().
*
- * Here all the payload has been dequeued, but
- * hvs_channel_readable_payload() still returns 1,
- * because the VMBus ringbuffer's read_index is not
- * updated for the FIN packet: hvs_stream_dequeue() ->
- * hv_pkt_iter_next() updates the cached priv_read_index
- * but has no opportunity to update the read_index in
- * hv_pkt_iter_close() as hvs_stream_has_data() returns
- * 0 for the FIN packet, so it won't get dequeued.
+ * If hvs->recv_desc points to the FIN packet, here all
+ * the payload has been dequeued and the peer_shutdown
+ * flag is set, but hvs_channel_readable_payload() still
+ * returns 1, because the VMBus ringbuffer's read_index
+ * is not updated for the FIN packet:
+ * hvs_stream_dequeue() -> hv_pkt_iter_next() updates
+ * the cached priv_read_index but has no opportunity to
+ * update the read_index in hv_pkt_iter_close() as
+ * hvs_stream_has_data() returns 0 for the FIN packet,
+ * so it won't get dequeued.
+ *
+ * In case hvs->recv_desc points to a malformed/short
+ * packet, return -EIO.
*/
+ if (!(vsk->peer_shutdown & SEND_SHUTDOWN))
+ return -EIO;
+
return 0;
}
--
2.49.0
