3 files changed, 76 insertions, 0 deletions

diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index bfe562c36469..b94378afea25 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -123,5 +123,7 @@ static inline int security_netlbl_sid_to_secattr(u32 sid,
 }
 #endif /* CONFIG_NETLABEL */
 
+const char *security_get_initial_sid_context(u32 sid);
+
 #endif /* _SELINUX_SECURITY_H_ */
 
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index 93b3177c7585..e24235c59ddf 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -102,6 +102,9 @@ enum sel_inos {
         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
 };
 
+#define SEL_INITCON_INO_OFFSET  0x01000000
+#define SEL_INO_MASK            0x00ffffff
+
 #define TMPBUFLEN       12
 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
                                 size_t count, loff_t *ppos)
@@ -1240,6 +1243,55 @@ out:
         return ret;
 }
 
+static ssize_t sel_read_initcon(struct file * file, char __user *buf,
+                                size_t count, loff_t *ppos)
+{
+        struct inode *inode;
+        char *con;
+        u32 sid, len;
+        ssize_t ret;
+
+        inode = file->f_path.dentry->d_inode;
+        sid = inode->i_ino&SEL_INO_MASK;
+        ret = security_sid_to_context(sid, &con, &len);
+        if (ret < 0)
+                return ret;
+
+        ret = simple_read_from_buffer(buf, count, ppos, con, len);
+        kfree(con);
+        return ret;
+}
+
+static const struct file_operations sel_initcon_ops = {
+        .read           = sel_read_initcon,
+};
+
+static int sel_make_initcon_files(struct dentry *dir)
+{
+        int i, ret = 0;
+
+        for (i = 1; i <= SECINITSID_NUM; i++) {
+                struct inode *inode;
+                struct dentry *dentry;
+                dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
+                if (!dentry) {
+                        ret = -ENOMEM;
+                        goto out;
+                }
+
+                inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
+                if (!inode) {
+                        ret = -ENOMEM;
+                        goto out;
+                }
+                inode->i_fop = &sel_initcon_ops;
+                inode->i_ino = i|SEL_INITCON_INO_OFFSET;
+                d_add(dentry, inode);
+        }
+out:
+        return ret;
+}
+
 static int sel_make_dir(struct inode *dir, struct dentry *dentry)
 {
         int ret = 0;
@@ -1336,6 +1388,21 @@ static int sel_fill_super(struct super_block * sb, void * data, int silent)
         ret = sel_make_avc_files(dentry);
         if (ret)
                 goto err;
+
+        dentry = d_alloc_name(sb->s_root, "initial_contexts");
+        if (!dentry) {
+                ret = -ENOMEM;
+                goto err;
+        }
+
+        ret = sel_make_dir(root_inode, dentry);
+        if (ret)
+                goto err;
+
+        ret = sel_make_initcon_files(dentry);
+        if (ret)
+                goto err;
+
 out:
         return ret;
 err:
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index d3698568a213..21b8318979e3 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -593,6 +593,13 @@ static int context_struct_to_string(struct context *context, char **scontext, u3
 
 #include "initial_sid_to_string.h"
 
+const char *security_get_initial_sid_context(u32 sid)
+{
+        if (unlikely(sid > SECINITSID_NUM))
+                return NULL;
+        return initial_sid_to_string[sid];
+}
+
 /**
  * security_sid_to_context - Obtain a context for a given SID.
  * @sid: security identifier, SID