n_gsm: Fix length handling

If the mux is configured with a large mru/mtu the existing code gets the
byte ordering wrong for the header.

Signed-off-by: Ken Mills <ken.k.mills@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 7f79044ae99..81b46585edf 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -716,8 +716,8 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg)
                 if (msg->len < 128)
                         *--dp = (msg->len << 1) | EA;
                 else {
-                        *--dp = (msg->len >> 6) | EA;
-                        *--dp = (msg->len & 127) << 1;
+                        *--dp = ((msg->len & 127) << 1) | EA;
+                        *--dp = (msg->len >> 6) & 0xfe;
                 }
         }