LSM/SELinux: show LSM mount options in /proc/mounts

This patch causes SELinux mount options to show up in /proc/mounts.  As
with other code in the area seq_put errors are ignored.  Other LSM's
will not have their mount options displayed until they fill in their own
security_sb_show_options() function.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/security/dummy.c b/security/dummy.c
index 1db712d99dc7..c155f08e9dd8 100644
--- a/security/dummy.c
+++ b/security/dummy.c
@@ -194,6 +194,11 @@ static int dummy_sb_kern_mount (struct super_block *sb, void *data)
         return 0;
 }
 
+static int dummy_sb_show_options(struct seq_file *m, struct super_block *sb)
+{
+        return 0;
+}
+
 static int dummy_sb_statfs (struct dentry *dentry)
 {
         return 0;
@@ -1088,6 +1093,7 @@ void security_fixup_ops (struct security_operations *ops)
         set_to_dummy_if_null(ops, sb_free_security);
         set_to_dummy_if_null(ops, sb_copy_data);
         set_to_dummy_if_null(ops, sb_kern_mount);
+        set_to_dummy_if_null(ops, sb_show_options);
         set_to_dummy_if_null(ops, sb_statfs);
         set_to_dummy_if_null(ops, sb_mount);
         set_to_dummy_if_null(ops, sb_check_sb);