From: Kees Cook <keescook@chromium.org>
Date: Thu, 8 Sep 2016 22:35:59 +0000 (-0700)
Subject: pty: make ptmx file ops read-only after init
X-Git-Tag: archive/raspbian/4.9.13-1+rpi1~10^2~1479^2~48
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=d2ec3f77de8e;p=linux-4.9.git

pty: make ptmx file ops read-only after init

The ptmx_fops structure is only changed during init, so mark it as such.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 51e0d32883ba..a23fa5ed1d67 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -800,7 +800,7 @@ out_free_file:
 	return retval;
 }
 
-static struct file_operations ptmx_fops;
+static struct file_operations ptmx_fops __ro_after_init;
 
 static void __init unix98_pty_init(void)
 {