n_tty: Fix auditing support for cannonical mode

Commit 32f13521ca68bc624ff6effc77f308a52b038bf0
("n_tty: Line copy to user buffer in canonical mode")
changed cannonical mode copying to use copy_to_user
but missed adding the call to the audit framework.
Add in the appropriate functions to get audit support.

Fixes: 32f13521ca68 ("n_tty: Line copy to user buffer in canonical mode")
Reported-by: Miloslav Trmač <mitr@redhat.com>
Signed-off-by: Laura Abbott <labbott@fedoraproject.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 14 insertions, 3 deletions

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 759604e57b24..396344cb011f 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -162,6 +162,17 @@ static inline int tty_put_user(struct tty_struct *tty, unsigned char x,
         return put_user(x, ptr);
 }
 
+static inline int tty_copy_to_user(struct tty_struct *tty,
+                                        void __user *to,
+                                        const void *from,
+                                        unsigned long n)
+{
+        struct n_tty_data *ldata = tty->disc_data;
+
+        tty_audit_add_data(tty, to, n, ldata->icanon);
+        return copy_to_user(to, from, n);
+}
+
 /**
  *      n_tty_kick_worker - start input worker (if required)
  *      @tty: terminal
@@ -2084,12 +2095,12 @@ static int canon_copy_from_read_buf(struct tty_struct *tty,
                     __func__, eol, found, n, c, size, more);
 
         if (n > size) {
-                ret = copy_to_user(*b, read_buf_addr(ldata, tail), size);
+                ret = tty_copy_to_user(tty, *b, read_buf_addr(ldata, tail), size);
                 if (ret)
                         return -EFAULT;
-                ret = copy_to_user(*b + size, ldata->read_buf, n - size);
+                ret = tty_copy_to_user(tty, *b + size, ldata->read_buf, n - size);
         } else
-                ret = copy_to_user(*b, read_buf_addr(ldata, tail), n);
+                ret = tty_copy_to_user(tty, *b, read_buf_addr(ldata, tail), n);
 
         if (ret)
                 return -EFAULT;