From 9fd973e085f7759f710603422b2e11ad5f2e000d Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Wed, 30 Jan 2013 18:50:54 -0800
Subject: coda: Restrict coda messages to the initial pid namespace

Remove the slight chance that pids in coda messages will be
interpreted in the wrong pid namespace.

- Explicitly send all pids in coda messages in the initial pid
  namespace.
- Only allow mounts from processes in the initial pid namespace.
- Only allow processes in the initial pid namespace to open the coda
  character device to communicate with coda.

Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 fs/coda/psdev.c | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'fs/coda/psdev.c')

diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c
index 761d5b31b18d..dd60f905d4fe 100644
--- a/fs/coda/psdev.c
+++ b/fs/coda/psdev.c
@@ -37,6 +37,7 @@
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/device.h>
+#include <linux/pid_namespace.h>
 #include <asm/io.h>
 #include <asm/poll.h>
 #include <asm/uaccess.h>
@@ -266,6 +267,9 @@ static int coda_psdev_open(struct inode * inode, struct file * file)
 	struct venus_comm *vcp;
 	int idx, err;
 
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
 	idx = iminor(inode);
 	if (idx < 0 || idx >= MAX_CODADEVS)
 		return -ENODEV;
-- 
cgit