n_tty: Only process packet mode data in raw mode

Packet mode can only be set for a pty master, and a pty master is
always in raw mode since its termios cannot be changed.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 7f134b9..6dcaa52 100644 (file)
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -2228,16 +2228,6 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
                }
                __set_current_state(TASK_RUNNING);
 
-               /* Deal with packet mode. */
-               if (packet && b == buf) {
-                       if (tty_put_user(tty, TIOCPKT_DATA, b++)) {
-                               retval = -EFAULT;
-                               b--;
-                               break;
-                       }
-                       nr--;
-               }
-
                if (ldata->icanon && !L_EXTPROC(tty)) {
                        retval = canon_copy_from_read_buf(tty, &b, &nr);
                        if (retval == -EAGAIN) {
@@ -2247,6 +2237,17 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
                                break;
                } else {
                        int uncopied;
+
+                       /* Deal with packet mode. */
+                       if (packet && b == buf) {
+                               if (tty_put_user(tty, TIOCPKT_DATA, b++)) {
+                                       retval = -EFAULT;
+                                       b--;
+                                       break;
+                               }
+                               nr--;
+                       }
+
                        /* The copy function takes the read lock and handles
                           locking internally for this case */
                        uncopied = copy_from_read_buf(tty, &b, &nr);