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>
diff --git a/fs/coda/inode.c b/fs/coda/inode.c
index be2aa49..77bbaf4 100644
--- a/fs/coda/inode.c
+++ b/fs/coda/inode.c
@@ -20,6 +20,7 @@
#include <linux/file.h>
#include <linux/vfs.h>
#include <linux/slab.h>
+#include <linux/pid_namespace.h>
#include <asm/uaccess.h>
@@ -157,6 +158,9 @@
int error;
int idx;
+ if (task_active_pid_ns(current) != &init_pid_ns)
+ return -EINVAL;
+
idx = get_device_index((struct coda_mount_data *) data);
/* Ignore errors in data, for backward compatibility */
diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c
index 761d5b3..dd60f90 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 @@
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;
diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c
index 0c68fd3..5c6d2cd 100644
--- a/fs/coda/upcall.c
+++ b/fs/coda/upcall.c
@@ -50,8 +50,8 @@
return ERR_PTR(-ENOMEM);
inp->ih.opcode = opcode;
- inp->ih.pid = current->pid;
- inp->ih.pgid = task_pgrp_nr(current);
+ inp->ih.pid = task_pid_nr_ns(current, &init_pid_ns);
+ inp->ih.pgid = task_pgrp_nr_ns(current, &init_pid_ns);
inp->ih.uid = current_fsuid();
return (void*)inp;
