selinux: correctly label /proc inodes in use before the policy is loaded
[pandora-kernel.git] / security / selinux / hooks.c
index 1dd9484..d5d67c9 100644 (file)
@@ -1402,15 +1402,33 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
                isec->sid = sbsec->sid;
 
                if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
-                       if (opt_dentry) {
-                               isec->sclass = inode_mode_to_security_class(inode->i_mode);
-                               rc = selinux_proc_get_sid(opt_dentry,
-                                                         isec->sclass,
-                                                         &sid);
-                               if (rc)
-                                       goto out_unlock;
-                               isec->sid = sid;
-                       }
+                       /* We must have a dentry to determine the label on
+                        * procfs inodes */
+                       if (opt_dentry)
+                               /* Called from d_instantiate or
+                                * d_splice_alias. */
+                               dentry = dget(opt_dentry);
+                       else
+                               /* Called from selinux_complete_init, try to
+                                * find a dentry. */
+                               dentry = d_find_alias(inode);
+                       /*
+                        * This can be hit on boot when a file is accessed
+                        * before the policy is loaded.  When we load policy we
+                        * may find inodes that have no dentry on the
+                        * sbsec->isec_head list.  No reason to complain as
+                        * these will get fixed up the next time we go through
+                        * inode_doinit() with a dentry, before these inodes
+                        * could be used again by userspace.
+                        */
+                       if (!dentry)
+                               goto out_unlock;
+                       isec->sclass = inode_mode_to_security_class(inode->i_mode);
+                       rc = selinux_proc_get_sid(dentry, isec->sclass, &sid);
+                       dput(dentry);
+                       if (rc)
+                               goto out_unlock;
+                       isec->sid = sid;
                }
                break;
        }